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LIBRARY
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University

 

 

This is to certify that the

thesis entitled

Correlation Between the Solubilitwaarameter as a Measure
of SorbatelPolymer Compatibility and Sorbate Equilibrium~
Solubility in a Two-Phase Aqueous/Polymer System

presented by

Palarp Sailabada

has been accepted towards fulfillment
of the requirements for

V Master__ degree in _P_at':kagin.g_

QM [yttaé‘

Major professor

Date—MELIL—Zflfll.

07639 MS U is an Affirmative Action/Equal Opportunity Institution

PLACE IN REI‘URN Box to remove this checkout from your record.
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' iii-1’ {l

0‘
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6/01 cJClRC/Duteouopes-nts

 

 

 

 

CORRELATION BETWEEN THE SOLUBILITY PARAMETER AS A MEASURE
OF SORBATE/POLYMER COMPATIBILITY AND SORBATE EQUILIBRIUM
SOLUBILITY IN A TWO-PHASE AQUEOUS/POLYMER SYSTEM

BY

Palarp Sailabada

A THESIS

Submitted to
Michigan State University
in partial fulfillment of the requirements
for the degree of

MASTER OF SCIENCE

School of Packaging

2001

ABSTRACT

CORRELATION BETWEEN THE SOLUBILITY PARAMETER AS A MEASURE
OF SORBATE/POLYMER COMPATIBILITY AND SORBATE EQUILIBRIUM
SOLUBILITY IN A TWO-PHASE AQUEOUS/POLYMER SYSTEM

By

Palarp Sailabada

Partition coefficient (K) values of the aqueous/polymer systems were
obtained using two experimental methods, TSfTD-GC and SPME-GC. The K
values of limonene, ethyl acetate, methyl ethyl ketone and toluene in LDPE and
in the water system were 200.85, 2.79, 0.54 and 95.46 respectively using TS/TD-
GC. The K values of limonene, ethyl acetate, methyl ethyl ketone and toluene in
LDPE and in the water system were 59.64, 1.09, 0.58 and 112.23 respectively
using SPME-GC. The solubility parameter value was calculated using the
solubility parameter program. The solubility parameter values determined for
limonene, ethyl acetate, methyl ethyl ketone and toluene were 4.70, 13.37, 13.35
and 6.36 (J/cm3)"2 respectively. When the solubility parameter values were less
than or equal to 5, good solubility occurred. Therefore, a high degree of
compatibility can be expected between sorbate and polymer. This was reflected
in the high partition coefficient values. Finally, the correlation between the
solubility parameter as a measure of sorbate/polymer compatibility and sorbate
equilibrium solubility in a two-phase aqueous/polymer system was established

using an exponential regression equation.

To my mom and dad and especially to Dr.Jack R. Giacin

ACKNOWLEDGMENTS

First of all, I would like to say thank you to Dr.Jack R. Giacin, my major
professor, who always so generous to help, teach, and suggest me with all of any
difficulties throughout my research. Dr.Ruben J. Hernandez and Dr.Randolph M.
Beaudry for their good advises and suggestions as members of my graduate
committees. And special thank to Dr.Bruce R. Harte who helps me finish this
thesis paper after Dr. Giacin had pass away.

Next, I would like to thank my mom (Dr.Chitra Sailabada) and dad
(Maj.Gen. Preecha Sailabada) for their love, support and encourage me to do my
best for everything I did.

Mr.Thaneth Watanakosin for encouraging me to fight with all troubles. He
also teaches me how to think and plan for my work. Thank you for your love.

Special thanks to all friend and people in the School of Packaging whom

always been so kind to help me with the instruments and cheer me up for good.

TABLE OF CONTENTS

Page
List of Tables ................................................................................................. vii
List of Figures ................................................................................................. ix
Introduction ...................................................................................................... 1
Chapter 1. Literature Review ........................................................................... 3
1.1 Solubility Parameter ........................................................................ 3
1.2 Partition Coefficient ......................................................................... 7
1.3 Solid Phase Microextraction ............................................................ 9
1.4 Dynamic Thermal Stripper/Thermal Desorption ............................ 14
Chapter 2. Materials and Methods ................................................................. 16
2.1 Polymer ......................................................................................... 16
2.2 Determination of partition coefficient of sorbates in LDPE film
and water ........................................................................ 16
2.2.1 Solvents ................................................................................ 16
2.2.2 Solutes .................................................................................. 17
2.2.3 Instruments ........................................................................... 17
Sample Preparation .................................................................. 18
2.3 Determination of sorbates in polymer phase ................................. 20
2.3.1 Instruments ........................................................................... 20
2.4 Determination of sorbates in liquid (aqueous) phase .................... 23
2.4.1 Instruments ........................................................................... 23
Chapter 3. Results and Discussion ................................................................ 26
3.1 Determination of the partition coefficient of several
aqueous/polymer systems using TS/TD-GC method ..................... 26
3.2 Determination of the partition coefficient of several
aqueous/polymer systems using SPME-GC method ................... 29
3.3 Determination of the solubility parameter values of
aqueous/polymer systems the solubility parameter program ..... 32

3.4 Correlation between the solubility parameters using Hoy method
and partition coefficient (K) of the sorbates in a two-phase,
aqueous/polymer system ............................................................... 37

3.5 Correlation between the solubility parameters using Hoftyzer
and Van Krevelen method and partition coefficient (K) of the

sorbates in a two-phase, aqueous/polymer system ................ 38
Chapter 4. Summary and Conclusion ............................................................ 41
Appendices .................................................................................................... 43
Appendix A. The solubility parameter program ................................... 44
Appendix B. Standard calibration curve for thermal desorption .......... 65
Appendix C. Standard calibration curve for solid phase

Microextraction .............................................................. 69

Appendix D. Calculation method for the partition coefficient by
TS/TD-GC method ............................................... 73

Appendix E. Calculation method for the partition coefficient by

SPME-GC method ......................................................... 74
Appendix F. Structures and details of sorbates and polymer .............. 75
Bibliography ................................................................................................... 76

vi

LIST OF TABLES

Page
Table 2.3.1. Thermal and flow rate conditions used for the thermal stripper..21
Table 2.3.2. Thermal and flow rate conditions used for the thermal
desorption .................................................................................. 22
Table 2.3.3. Gas chromatographic thermal conditions, injection and
retention times necessary to separate sorbates using the

gas chromatograph procedure ................................................... 22
Table 2.4.1. Gas chromatograph conditions used to separate sorbates ........ 24
Table 3.1.1. Partition coefficient values for limonene in a LDPE film and

water system .............................................................................. 27
Table 3.1.2. Partition coefficient values for ethyl acetate in a LDPE film and

water system .............................................................................. 27
Table 3.1.3. Partition coefficient values for methyl ethyl ketone in a LDPE

film and water system ................................................................ 27
Table 3.1.4. Partition coefficient values for toluene in a LDPE film and

water system .............................................................................. 28

Table 3.1.5. Partition coefficient values of the aqueous/polymer systems ..... 28
Table 3.2.1. Partition coefficient values for limonene in a LDPE film and

water system .............................................................................. 29
Table 3.2.2. Partition coefficient values for ethyl acetate in a LDPE film and

water system .............................................................................. 29
Table 3.2.3. Partition coefficient values for methyl ethyl ketone in a LDPE

film and water system ................................................................ 30
Table 3.2.4. Partition coefficient values for toluene in a LDPE film and

water system .............................................................................. 30

Table 3.2.5. Partition coefficient values of the aqueous/polymer systems ..... 30
Table 3.2.6. Partition coefficient values of the aqueous/polymer systems
using the TS/T D and SPME method .......................................... 31
Table 3.3.1. Three-dimensional (3-D) solubility parameters of LDPE and
sorbates as calculating using the solubility parameter program.36
Table 3.3.2. Solubility parameter values of the sorbates/LDPE systems ....... 36
Table 3.4. Partition coefficients and solubility parameters using Hoy
method of the aqueous/polymer systems ..................................... 37
Table 3.5. Partition coefficients and solubility parameters using Hoftyzer
and Van Krevelen method of the aqueous/polymer systems ........ 39
Table A1. Solubility Parameter component group contributions (Method of

Hoftyzer-Van krevelen) ................................................................. 46
Table A2. The equations to be used in Hoy’s system for estimation of the
solubility parameter and its components ...................................... 47
Table A3. Values of increments in Hoy’s system for the molar attraction
function ......................................................................................... 48
Table A4. Database of the solubility parameter values of sorbates from the
solubility parameter program ........................................................ 49

vii

Table 3.1.

Calibration data for ethyl acetate in acetonitrile with 1 pl injection

volume by TD-GC ......................................................................... 65
Table 3.2. Calibration data for limonene in acetonitrile with 1 pl injection

volume by TD-GC ......................................................................... 66
Table 8.3. Calibration data for methyl ethyl ketone in xylene with 1 pl

injection volume by TD-GC ........................................................... 67
Table 3.4. Calibration data for toluene in acetonitrile with 1 pl injection

volume by TD-GC ......................................................................... 68
Table C.1. Calibration data for ethyl acetate in water by SPME-GC .............. 69
Table 0.2. Calibration data for limonene in water by SPME-GC .................... 70
Table 0.3. Calibration data for methyl ethyl ketone in water by SPME-GC ...71
Table C.4. Calibration data for toluene in water by SPME-GC ...................... 72
Table F. Structure and details of sorbates and polymer ................................. 75

viii

LIST OF FIGURES

Page
Figure 1.1. Solubility of polystyrene in various solvents ................................... 6
Figure 1.3.1. Solid Phase Microextraction device .......................................... 10
Figure 1.3.2. Sequence of events showing extraction steps and
desorption steps using SPME .................................................. 11
Figure 2.2.1. Sorption Cell ............................................................................. 19

Figure 3.4. Correlation between average partition coefficients using the
TSfTD-GC and SPME-(3C method and solubility parameters
using Hoy method ....................................................................... 38

Figure 3.5. Correlation between average partition coefficients using the
TS/TD-GC and SPME-GC method and solubility parameters

using Hoftyzer and Van Krevelen method ................................... 40
Figure A.1. Example of solubility parameter program of Hoy method ............ 44
Figure A.2. Example of solubility parameter program of Hoftyzer and
Van Krevelen method .................................................................. 45

Figure B.1. Standard calibration curve of ethyl acetate in acetonitrile

by TD-GC ................................................................................. 65
Figure 8.2. Standard calibration curve of limonene in acetonitrile

by TD-GC ................................................................................. 66
Figure B.3. Standard calibration curve of methyl ethyl ketone in xylene

by TD-GC ................................................................................. 67
Figure 8.4. Standard calibration curve of toluene in acetonitrile

by TD-GC ................................................................................. 68
Figure 0.1. Standard calibration curve of ethyl acetate in water

by SPME-GC ............................................................................ 69
Figure C.2. Standard calibration curve of limonene in water

by SPME-GC ............................................................................ 70
Figure C.3. Standard calibration curve of methyl ethyl ketone in water

by SPME-GC ............................................................................ 71
Figure 0.4. Standard calibration curve of for toluene in water

by SPME-GC ............................................................................ 72

INTRODUCTION

The solubility parameter (8) was proposed in 1949 by Hilderbrand as a
help explain the behavior of specific solvents (Van Krevelen, 1990). The
solubility parameter (8) is widely used to illustrate the mutual affinity of
sorbate/polymer systems. Thus, it is an important characteristic which can be
used to estimate the interaction or compatibility between product constituents
and polymeric packaging systems. Normally, the solubility of a given sorbate in
different polymers can be approximated by its chemical structure. Therefore,
measurement of the solubility parameter is a method which can be used to
indicate the probability of sorbate/polymer compatibility. Similar solubility
parameters for two substances (i.e. sorbate/polymer system) indicate the
compatibility of those substances. The solubility parameter can be used as a
useful indicator of sorbate/polymer interaction to select a suitable package for a
product, where quality is related to the retention of organic volatiles.

In considering the solubility parameter as a measure of sorbate/polymer
compatibility, it is important to understand that this concept is not proposed as a
substitute for actual storage stability or compatibility studies. It is a useful tool,
which can result in the sound selection of polymeric package systems and may
reduce the number of samples which need to be evaluated in long term stability
studies.

In terms of practical utility, the results of this research have the following

applications;

. Predict the compatibility of a product for a given packaging
material.
. Aid in selecting the most suitable packaging material for a given
package-product-environment system.
. Provide an alternative to accelerated storage studies for evaluating
candidate-packaging systems.
. Reduce development time.
This study will focus on estimating the affinity of organic sorbates in a selected
polymer, using three-dimensional (3-D) solubility parameters and to establish a
correlation between the solubility parameters and equilibrium partition coefficient

(K) for the sorbates in a two-phase, aqueous/polymer system.

Chapter 1

LITERATURE REVIEW

1.1 Solubilig parameter

The solubility parameter provides a simple method of correlating and
predicting the cohesive and adhesive properties of materials from knowledge of
the properties of the components. For polymers, applications include finding
compatible solvents for coating resins, predicting the swelling of cured
elastomers by solvents, estimating solvent pressure in devolatilization and
reactor equipment and predicting polymer-polymer; polymer-binary-solvent;
random copolymer, and multicomponent solvent equilibria. Cohesive energy was
the basis of the original definition by Hilderbrand and Scott for what is now called
the solubility parameter (Du, et al 1996).

According to Hilderbrand (Van Krevelen, 1990), the enthalpy of mixing can

be calculated by the following equation:

[mm = prism-63f (1.1.1)

where A Hm enthalpy of mixing per unit volume
4),, and (is = volume fractions of components
(i.e., polymer and sorbate, respectively)
8,, and 53 = solubility parameters of components
(i.e., polymer and sorbate, respectively).

From equation (1.1.1), the two components should be mutually soluble if

A HI.1 is equal or near to zero. This means that the solubility parameters of the

two components (i.e. 5p and 85) should be equal or close. Therefore, components
with similar chemical structures and similar solubility parameters should easily
dissolve in each other and exhibit a high propensity for sorbate/polymer
interaction or compatibility. As large differences between solubility parameters of
substances (i.e. sorbate/polymer) occur, lower solubility values are expected.
However, in equation (1.1.1), it was assumed that there are no specific forces
between the structural units of the substances involved, but only dispersive
forces. If one of the substances involved contains strongly polar groups or
hydrogen bonds, A Hm may become higher than that calculated from equation
(1.1.1) and solubility may not occur, even when the values of the solubility
parameter are close or equal. On the other hand, if both substances involved
contain intermolecular forces such as van der Waals forces, hydrogen bonding,
or dipole interactions, solubility may be promoted, even if the solubility parameter
values differ significantly (Van Krevelen, 1995).

A more specific treatment of the solubility concept was desired for
situations where there is interaction between polymer and sorbate. The
component group contribution methods of Hoy (Hoy, 1970) and of Hoftyzer and
Van Krevelen (Hoftyzer, 1990) afford such a treatment and can be applied in
cases to estimate the solubility parameters of sorbate/polymer systems. The

component group contribution method provides the total solubility parameter (8)
as well as the dispersion (5d), polar (5p), and hydrogen bonding (8..) contributions

to the solubility parameter. The total, or 3-dimensional (3-D) solubility parameter

8‘, is described as the sum of these respective solubility parameter components.

/2
5. = (63 +53 +5§I (1.1.2)
An estimation of the solubility or compatibility of a sorbate molecule in a

polymer, when dispersion, polar and hydrogen bonding contributions are

considered, is shown in equation (1 .1.3);

A6 = [(a‘dm —5d,s)2 +(5p,p —5p,,)2 +(5h,p —5h,s)2I/2 (1.1.3)

where 6”, 8M, and 5m) are the dispersion, polar and hydrogen bonding
solubility parameter values for the polymer and 8,1,3, 8p.s, and 8M are the

dispersion, polar and hydrogen bonding solubility parameter values for the
sorbate, respectively.
Thermodynamic considerations Ier Bagley et al. (1971) to the conclusion

that the effects of 8.. and 5p show close similarity, whil the effect of 8,. is of a quit

different nature. Accordingly, they introduced the parameter 8,, = (Iii): + 8% I.

This leads to a diagram in which 8, and 8.. are plotted on the axes. Such a
diagram is shown in figure 1.1 for the interaction between polystyrene and a
number of solvents. A majority of the points for good solvents indeed fall in a
single region of figure 1.1. The solubility region can approximately be delimited

by a circle with a radious of about 5 8-units. For extensive chemical activity or

solubility of a sorbate molecule in a polymer matrix, the value Z6 should be less

than or equal to 5 (s 5) (Van Krevelen, 1990).

 

* polystyrene
5h - soluble
almost soluble

20 - , Strongly swollen
swollen

slightly swollen
' no effect

D

O

)I

 

 

 

 

25
—__> 8v

Figure 1.1. Solubility of polystyrene in various solvents (Van Krevelen, 1990)

To facilitate determination of solubility parameter values and solution of
equation (1.1.3) for 36 values, a computer program was developed which has a
data base of solubility parameter values and the associated 8,1,9, 8”, and 6.”,
values for a series of commodity polymer structures, as well as group

contribution tables (Hoy 1970) and (Hoftyzer and Van Krevelen 1990), which will

allow ready determination of the solubilityparameter values for organic sorbates,

given their molecular structure. The program also determines both associated

8”, 8pm, and 8.”, values and 8,1,3, 8”, and 8“ values, as well as providing a value

for Z6 as a prediction of sorbate/polymer affinity (Stephane, 1995).

1.2 Partition coefficient

Food/package interactions can be defined as chemical and/or physical

reactions between a food, its package and the environment, which may change

the composition, quality, or physical properties of the food and/or package. In

general, food/package interactions can be divided into four types, which are

(Hotchkiss, 1995):

Migration can be defined as the transfer of package components to the
product. This can result in safety concerns and flavor degradation.

Scalping can be defined as the transfer of product components to the
package. The transfer of desirable aromas from food to packaging can result
in flavor alteration and/or loss of package performance.

Egress permeation which is the transfer of product components through the
package to the environment. Loss of aroma-flavor volatiles, 002, or H20 can
result in changes in food quality.

Ingress permeation which is the transfer of environmental components
through the package to the product. Ingress of 02, H20, light or undesirable

odors or toxicants can be detrimental.

The loss of volatile low molecular mass organic compounds from a food into
polymeric packaging materials, based on a sorption mechanism is of major
concern and continues to be a subject of study. Sorption, or the uptake of
volatile components by the polymeric packaging material from food, may also
result in increased permeability to other permeants, lower chemical and
mechanical resistance of the packaging material, and/or affect the kinetics of the
migration process (Giacin, 1995). The overall effect may result in the loss of
aroma and flavor volatiles associated with product quality, as well as other
volatile organic food components during package storage. In food
product/package systems, the characterization of sorption behavior is necessary
for quality control and prediction of change in product quality, as related to the
loss of components associated with product shelfiife. Sorption is measured as a
function of sorbate concentration by a sorption equilibrium isotherm that can be
described by Henry’s Law or other mathematical models. For a specific value of
concentration, the partition coefficient (K) is a practical way to describe the
change in organic sorbate concentration, either in the food or packaging, from
the moment that food product and packaging material are contacted, up to the
moment they reach equilibrium (Giacin, 1995). Here, the partition coefficient is
defined as the equilibrium concentration of sorbate in the polymer phase [Cp]
divided by the equilibrium concentration of sorbate in the aqueous phase [Ca].
For high solubility in the polymer phase, A8 should be less than 5 and therefore a

significant high partition should be expected.

Gavara et al., 1995 applied three experimental techniques to determine
the partition coefficient of toluene, d-limonene, and ethyl acetate between water
and polystyrene. The authors found that gas chromatography (GC) was an
excellent technique for determination of sorbate concentrations in the liquid
phase, especially for sorbates with high K values. The dynamic thermal
stripper/thermal desorption (DTS/T D) method was very useful for determination
of sorbate concentrations in the polymer phase. The applicability of this
technique was limited, however, by the retention capacity of the trap column and

its selectivity (Gavara et al., 1995).

1.3 Solid Phase Microextgction

Solid Phase Microextraction (SPME) is a solvent-free sample preparation
technique. The basic principle of this approach is to use a small amount of the
extraction phase, usually less than 1 pL. The SPME device consists of a 1 cm
length of fused silica fiber, coated on the outer surface with a stationary phase
and bonded to a stainless steel plunger, and a holder that looks like a modified

microliter syringe (Figure 1.3.1) (Supelco, 1997).

<——

   

Plunger
Barrel
Plunger retaining screw
z-slot x" ‘~\
I \
I, \\ . .
Hub-viewing window I/ <—‘-—, Septum-prercrng

‘, Needle

_ Adjustable needle
guide/depth gauge

 

Tensioning spring

‘-----
” Q-
‘ '
‘ G
~..---‘-.-

  

, Phase-coated Fused
/ Silica Fiber Exposed

 

 

'CI-§‘
‘u--—’

Figure 1.3.1. Solid Phase Microextraction device

The fused silica fiber can be drawn into a hollow needle using the plunger
on the fiber holder. Organic analytes are adsorbed onto the stationary phase
coated fiber, and adsorption equilibrium is attained in 2 to 30 minutes. After
sample adsorption, the fused silica fiber is drawn up into the needle, the needle
withdrawn from the sample vial and injected directly into the gas chromatograph,
where the sorbed analytes are thermally desorbed and delivered to a capillary

column for analysis. This is shown in sequence in Figure 1.3.2.

10

Extraction Procedure Desorption Procedure

Retract Fiber/ Retract Fiber/
Pierce Sample Expose Fiber/ Remove Pierce GC inlet Expose Fiber/ Remove
Septum Extract Septum Desorb

 

 

Figure 1.3.2. Sequence of events showing extraction steps and desorption
steps using SPME

The figure shows extraction and desorption (injection) steps necessary to
perform an analysis using SPME. The fiber is inserted directly into a liquid
sample with the subsequent absorption of most of the analyte molecules (small
circles) from the solution (Alan et al., 1997).

For different structural characteristics of an analyte, the phase type or
thickness of the fiber can be changed to enhance the stationary phase captive
capacity of the analyte. SPME is a fast, inexpensive and solvent free technique
that can be used to concentrate volatile, semi-volatile or non—volatile compounds
from liquid samples or headspace. In the first process, the coated fiber is
exposed to the sample, and the target analyte are extracted from the sample

matrix into the coating. The fiber with concentrated analytes is then transferred

11

to an instrument where the analytes are thermally desorbed, separated and
quantified by the detector. SPME can be used directly with any gas
chromatograph or gas chromatograph-mass spectrometer system.

The principle behind SPME is the partitioning of analytes between the
sample matrix and the extraction medium (Zhang 1994). If a liquid polymeric
coating is used, the amount of analyte absorbed by the coating at equilibrium is

directly related to its concentration in the sample, as shown in equation 1.3.1.

K vc v
n = f5 f 0 5 (1.3.1)
Kfsz+VS

 

where n is the mass of an analyte absorbed by the coating; Vf and V, are the
volumes of the coating and the sample, respectively; K,‘ is the partition

coefficient of the analyte between the coating and the sample matrix; and Co is

the initial concentration of the analyte in the sample. As equation 1.3.1 indicates,

if V9, is very large (Vs>>Kfs Vf), the amount of analyte extracted by the fiber

coating will not be related to the sample volume, as shown in equation 1.3.2.
n = Kfs VfCO (1.3.2)

In SPME, equilibria are established among the concentrations of an
analyte in the liquid or solid sample, in the headspace above the sample, and in
the fused silica fiber phase. The amount of analyte absorbed by the fiber
depends on the thickness of the stationary phase coating and the distribution
constant for the analyte. Extraction time is determined by the time required to
obtain precise extraction for the analyte with the highest distribution constant.

Full equilibration is not necessary for high accuracy and precision with SPME,

12

but consistent sampling time and other sampling parameters are essential. Vial
size, sample volume, and (for liquid samples) the depth the fiber is immersed into
the sample are all important to keep consistent.

Two important steps in SPME are extraction of the analytes from the
sample material, and desorbtion of them into an analytical instrument. A variety
of sorbents have been used for SPME, since different groups of analytes can be
extracted using different types of sorbents. The basic principle of “like dissolves
like” applies for organic compounds. The coating can be selected based on the
polarity and volatility characteristics of the analyte. One of the most useful
coatings is polydimethylsiloxane (PDMS), which is very rugged and able to
withstand injector temperatures up to 300 °C (Jnausz, 1999). PDMS is a non-
polar liquid phase, so it extracts non-polar analytes very well. However, it can be
applied to more polar compounds, particularly after optimizing extraction
conditions. SPME can be used to analyze a wide range of compounds in various
matrices through proper optimization or modification of SPME procedures.

Czenlvinski et al. (1996) used a polydimethylsiloxane coated fiber system
to determine the presence of myrcene, beta-pinene, limonene and menthol in
four herbal remedies utilizing a headspace procedure, with GC-MS analysis. The
detection limits were at the ppb level and 13 other compounds were identified.
Shirey (1997) compared the extraction limits of different coated fiber phases for
polar analytes in water samples. The results showed that
carboxen/polydimethylsiloxane fiber had superior extraction capability as

compared to the other coating phases, particularly, the more polar phases such

13

as Carbowaxm/divinylbenzene and polyacrylate coating fibers. The author
proposed that the small pores of carboxen/polydimethylsiloxane enables
extraction of analytes at higher orders of magnitude than other coated fiber
phases. Mersili (R&D magazine, 1999) evaluated the capabilities of SPME with
respect to off-flavor in milk and concluded that SPME is not only significantly
easier and faster to perform, but it has consistently demonstrated superior

accuracy and precision without sacrifice in sensitivity.

1.4 Qmapic Thermal Stripper/Thermal Desorption (DTS/T D)

The dynamic thermal stripper unit is a sample preparation instrument
designed to collect onto an adsorbent packed trap, a broad range of low to high
molecular weight compounds that are present at the parts per billion to parts per
million level. The thermal stripper system and the instrument parameters (i.e.
carrier gas flow rate, temperature program and collection time), as well as the
composition of the absorbent trap, are major factors contributing to the overall
performance of sample collection (Dynatherm, TS manual, 1989).

The thermal desorption unit is an instrument used for direct thermal
desorption of compounds from the sorbent tubes of the thermal stripper or a
dynamic purge and trap system. The system is easily installed on virtually any
gas chromatograph (60), with a heated transfer line inserted into the column
oven through an access hole or through one of the injectors. AlI zones of sample
transport may be heated to a maximum of 250 °C to prevent condensation of

higher molecular weight compounds. These features make the instrument ideal

14

for the analysis of sensitive environmental, food, flavor, and biological
compounds. The sorbent tubes are generally packed with layers of different
materials, so that a wide range of compounds having different molecular weight
and polarities may be trapped onto an appropriate sorbent. Each sorbent layer
protects the next increasingly active layer, and prevents a compound from being
held so tenaciously that it cannot be desorbed quickly and completely during the
trap and heat cycle, which is important to prevent degradation. Therefore, during
sample collection, the gas flow enters the sorbent tube at the least active layer of
sorbent material, and exits through the most tenacious layer (Dynatherm, TD
manual, 1989).

The TS/T D system, interfaced with 60 analysis has been used to
determine the sorbate concentration in a polymer sample by trapping the total
amount of sorbate from the polymer sample and quantitatively measuring the
desorbing analytes with G0 analysis. This method is acceptable in cases where

the amount of sorbate in the polymer is relatively low (Gavara et al, 1996)

15

Chapter 2

MATERIALS AND METHODS

Materials
2.1 Polymer
Low density polyethylene (LDPE) (thickness 1.19 mil, density 0.923

glcm3) was used as the test material for all research herein.

Methods
2.2 Deterrfltion of partition coefficient offisorbates in LDPE film and water

2.2.1 Solvents

The following solutions were used in this procedure;

Acetonitrile, CH3CN (HPLC Grade) from EM Industries, Inc. (Gibbstown,
NJ), molecular weight 41.05, density 0.78 glmL at 25°C, boiling range 82.0 i 0.1
°C, purity 99.8 %

1,2-Dichlorobenxene, 05H4Cl2 (HPLC Grade) from Aldrich Chemical
Company, Inc., molecular weight 147, density 1.306 g/mL at 25°C, boiling range
179-180 °C, purity 99.6 %

Dichloromethane, CH2CI2 (Analytical Reagent Grade) from Mallinckrodt,
Inc. (Paris, KY), molecular weight 84.93, density 1.316 g/mL at 25°C, boiling
range 40 °C, purity 99.9 %

Water, H20 (HPLC Grade) from J.T.Baker (Phillipsburg, NJ), molecular

weight 18.0, density 1.000, boiling range 100 °C, purity 100%

16

Xylenes, CsH4(CH3)2 (HPLC Grade) from EM Industries, Inc. (Gibbstown,
NJ), molecular weight 41.05, density 0.78 glmL at 25°C, boiling range 82.0 i 0.1
°C, purity 99.8 %

Methanol, CH3OH (HPLC Grade) from J.T. Baker (Phillipsburg, NJ),
Molecular weight 32.04, Density 0.791 glmL at 25°C, Boiling range 64.7 °C,
Purity 100.0 %

2.2.2 Solutes

 

Ethyl acetate, CH3COOC2H5 (GLC Grade) from Aldrich Chemical
Company, Inc., molecular weight 88.11, density 0.902 g/mL at 25°C, boiling
range 76.5-77.5 °C, purity 99.8 %

Limonene, C10H16 (GLC Grade) from Aldrich Chemical Company, Inc.,
molecular weight 136.24, density 0.840 glmL at 25°C, boiling range 175.5-176
°F, purity 97 %

Methyl ethyl ketone, CH300CH2CH3 (Analytical Reagent Grade) from
Mallinckrodt Specialty Chemical Co., molecular weight 72.11, density 0.803 glmL
at 25°C, boiling range 79.5-80.0 °C, purity 99.6 %

Toluene, 06H50H3 (Analytical Reagent Grade) from J.T. Baker Chemical
Co., molecular weight 92.14, density 0.865 glmL at 25°C, boiling range 110.6 °C,
purity 99.9 %

2.2.3 Instruments
Gas Chromatograph:

Hewlett Packard model 5890 A interfaced with HP 3395 integrator

(Avondale, PA)

17

Gas Chromatography Column (Fused Silica Capillary Column):
SPBTMS (non-polar bounded stationary phase) 30 m long, 0.32 mm ID,
1.0 pm film thickness (Supelco lnc., Bellefonte, PA)
Syringes:
500 mL Gas-tight syringe (Hamilton Co., Reno, NV)
5 pl syringe (Hamilton Co., Reno, NV)
Separatory funnel
Vial and cap:
40 mL amber vial (Supelco Inc., Bellefonte, PA)

open screw cap-teflonlsilicon septa (Supelco Inc., Bellefonte, PA)

Sample Preparation
Four sorbate solutions in water were obtained by separately mixing
ethyl acetate, limonene, methyl ethyl ketone and toluene with water in a
separatory funnel at room temperature (22:1:1°C) and allowing the solution to
stand for 24 hours. Each of the aqueous, transparent phases was then
separated as a primary aqueous sorbate solution. The concentrations of each

sorbate solution were then determined by solvent extraction following the method

of Gavara et al, 1995.

18

open-top screw cap-teflon/silicon septa closure

round disk shape (OD 21.69 mm)

glass bead

 

Figure 2.2.1. Sorption cell

Sorption cells for the determination of partition coefficient values consisted
of 40 mL amber glass vials with an open-top screw cap-teflon/silicon septa
closure. The LDPE film was cut into a round disk shape (0D 21.69 mm) with a
cork borer. Approximately 30 film disks were weighed and then mounted onto a
stainless steel wire, which was formed as a support stand threaded with glass
beads to separate the film disks, so as to allow two-sided contact. The mounted
film disks were then placed into the vial and it was filled with 40 mL of sorbate
solution, as shown in figure 2.2.1. Three sorption cells were prepared with one
blank cell (no film disks) per each sorption solution and the cells were stored at
room temperature (22i1°C) for 30 days. It was assumed that this storage time
would allow the system to attain equilibrium (Harita and Tanaka 1989). During
storage, the sorption cells were shaken by hand every 6-7 days (Baner, 1992).
At the end of the storage time, the quantity of the sorbates in the aqueous phase

was determined by a SPME method and the quantity of the sorbates sorbed by

19

the LDPE film determined using a TS/T D system interfaced with a gas
chromatograph (GC). The equilibrium partition coefficient (K) was then
determined by substitution into equation 2.2.1. The equilibrium partition
coefficient K is defined as the equilibrium concentration of sorbate in the polymer
phase [Cp] divided by the equilibrium concentration of sorbate in the aqueous

phase [Ca].

K = [cpl

m (2.2.1)
2.3 Determination of sorbat_es in polvmer phg_s_e_
2.3.1 Instruments
The following instruments were used in the above procedure;
Dynamic Thermal Stripper:
Dynathenn model 1000 thermal stripper unit (Dynatherm, Kelton PA)
20 mL sparging tube
Thermal Desorption:
Dynatherm 890/891 thermal desorption unit (Dynatherm, Kelton PA)
CarbotrapTM 300 multi-bed thermal desorption tubes; 6 mm OD. x 4 mm,
ID. x 11.5 cm length (Supelco lnc., Bellefonte, PA)
Gas Chromatograph:
Hewlett Packard model 5890 A interfaced with HP 3395 integrator
(Avondale, PA)

Gas Chromatography Column (Fused Silica Capillary Column):

20

SPBTM5 (non-polar bounded stationary phase) 30 m long, 0.32 mm ID,
1.0 pm film thickness (Supelco lnc., Bellefonte, PA)
Syringes:

500 mL Gas-tight syringe (Hamilton Co., Reno, NV)

5 pl syringe (Hamilton Co., Reno, NV)

The dynamic thermal stripper model 1000 (Dynatherm, Kelton, PA) and
thermal desorption model 890/891 (Dynathenn, Kelton, PA) interfaced with GC
analysis were used to analyze the concentration of the sorbate in the polymer
(LDPE) phase. After equilibrium, the polymer disks were immediately transferred
into 20 mL sparging tubes, placed in the oven of a thermal stripper instrument
and connected to sorption tubes containing CarbotrapTM 300 (Supelco Inc.,
Bellefonte, PA) mounted outside the oven. The conditions used for the thermal
stripper unit and thermal desorption are summarized in Table 2.3.1.

Table 2.3.1. Thermal and flow rate conditions used for the thermal stripper.

 

 

 

 

 

 

 

Preheat Purge Dry
He Flow rate, mL/min 50 100 50
Time, min 5 15 2
Block Oven Tube
Temperature, °C 150 110 75

 

 

After stripping, the carbotrap sorption tube containing the trapped sorbate
was transferred to the tube chamber of the thermal desorption unit. A transfer
line connected the thermal desorption unit to the GC. The sorbate was thermally
desorbed from the carbotrap matrix into the 60 using the conditions shown in

Tables 2.3.2 and 2.3.3 respectively.

21

 

Table 2.3.2. Thermal and flow rate conditions used for thermal desorption.

 

Tube desorption chamber temperature, °C
Valve compartment temperature, 00
Transfer line temperature, 00

Tube preparation chamber temperature, °C
Desorption time, min

Preparation time, min

 

Desorption carrier gas flow rate at flow check port, mUmin
Preparation carrier gas flow at side port, mUmin

 

370
250
250
350
8
30
9
1 5

 

 

Table 2.3.3. Gas chromatographic thermal conditions, injection and retention

times necessary to separate sorbates using the gas chromatograph procedure

 

 

Compound Ethyl Acetate Limonene mags?” Toluene
Injection Temperature, °C 200 200 200 200
Initial Temperature, °C 100 60 50 40
Initial Time, min 9 1 2 5
Rate, °C/min 10 10 10 10
Final Temperature, °C 220 200 200 200
Final Time, min 10 5 10 10
Detector Temperature, °C 250 250 250 250
Range 2 2 2 2
Retention Time, min 2.1 7.6 1.9 4.3

 

 

 

 

 

The concentration of sorbate in the polymer was calculated, and

substituted into the following equation.

ICpI =

where m is the mass of sorbate and mp is the mass of polymer

22

(2.3.1)

 

Standard calibration curves for the TD and GC procedures were
constructed for the analysis of sorbed levels of the respective sorbate from a
series of standard solutions of known concentration. A 1 pl volume of standard
solution of sorbate of known concentration was directly injected into the
carbotrapTM 300 tube. The sorption tube was then inserted into the heating
chamber of the thermal desorption unit, which was directly interfaced to the
column of the gas chromatograph, where the sorbates were separated. The
optimized conditions for the TD and GC procedures are shown in Table 2.3.2 and
2.3.3 respectively. The standard calibration curves of sorbates by thermal
desorption are shown in Appendix B.

2.4 Determination of sorbates in liquid (agueous) phase
2.4.1 Instruments
The following instruments were used in the above analysis;
Gas Chromatograph:
Hewlett Packard model 5890 A interfaced with HP 3395 integrator
(Avondale, PA) ’
Gas Chromatography Column (Fused Silica Capillary Column):
SPBTMS (non-polar bounded stationary phase) 30 m long, 0.32 mm ID,
1.0 pm film thickness (Supelco lnc., Bellefonte, PA)
Solid Phase Microextraction device
100 pm Polydimethylsiloxane (PDMS) fiber (Supelco lnc., Bellefonte, PA)

SPME manual injection syringe (Supelco Inc., Bellefonte, PA)

23

Determination of sorbate concentration levels in the aqueous phase was

carried out by solvent extraction and SPME with GC analysis. Sorbate

concentrations in the blank cell were evaluated and used as the initial sorbate

concentration. Concentrations of ethyl acetate, methyl ethyl ketone, and toluene

in the primary aqueous standard solution were determined by a one-step

extraction of the sorbate from the aqueous solution with dichlorobenzene,

followed by analysis using GC. A similar procedure was employed, for limonene,

in the primary aqueous standard solutions using dichloromethane as the

extracting solvent. The conditions for the analysis of sorbates by GC are shown

in table 2.4.1.

Table 2.4.1. Gas chromatograph conditions used to separate sorbates

 

Methyl Ethyl

 

 

 

 

 

 

Compound Ethyl Acetate Limonene Ket on e Toluene
Injection Temperature, °C 200 200 200 200
Initial oven Temperature, °C 100 60 50 40
Initial Time, min 9 1 2 5
Rate, °C/min 5 7 5 10
Final Temperature, °C 220 200 200 200
Final Time, min 10 5 10 10
Detector Temperature, °C 250 250 250 250
Range 2 2 2 2
Retention Time 1.7 7.6 2.0 4.3
ghent acetonitrile acetonitrile xylene acetonitrile

 

The SPME—GC procedure was used to determine the sorbate

concentration in the liquid (aqueous) phase of the polymer-aqueous phase

distribution system. After storing the filled sorption cell for 30 days, the sorbate

24

 

solution was extracted using SPME and then directly injected into the GC. The
extraction time for each sorbate was obtained from the time required to achieve
precise extraction of the sorbate with the highest distribution constant. The
extraction time for ethyl acetate, limonene, and methyl ethyl ketone was found to
be 4 minutes and for toluene were 10 minutes. The standard calibration curves
of known series dilutions of the sorbates concentration were constructed, as

shown in Appendix C.

25

Chapter 3

RESULTS AND DISCUSSION

Partition coefficient values of aqueous/polymer systems were obtained by
using two experimental methods, TS/TD-GC and SPME-GC. The solubility
parameter values were determined using a solubility parameter program. A
correlation between partition coefficient values and solubility parameter values

was established.

3.1 Determination of the pafrtition coefficient offleraj aqueous/polymer systems
15in the TSlTD-GC method

The partition coefficient of sorbates between LDPE film and water were
determined by measuring the sorbate concentration in polymer and the
remaining sorbate concentration in the aqueous phase. The partition coefficient
values (K) are reported as a ratio of the concentration of sorbate in the polymer
phase [Cp] divided by the concentration of sorbate in the aqueous phase [Ca].
Results for three sample systems and one blank control (no film disks-sorption
cell) were determined (Appendix D) and the results are summarized in Table
3.1.1, 3.1.2, 3.1.3, and 3.1.4 for limonene, ethyl acetate, methyl ethyl ketone and

toluene respectively.

26

Table 3.1.1. Partition coefficient values for limonene in a LDPE film and water

 

 

 

 

 

system'
Sample Cp(wtlwt) Ca(wt/wt) K
Blank - 4.58 x 1043 -
1 5.12x10'4 3.32x105 154.18
2 6.68 x 104 3.22 x 1013 207.42
3 7.81 x 104 3.24 x 1043 240.96
Average - - 200.85
Standard deviation - - 43.76
* TSfTD-GC method

Table 3.1.2. Partition coefficient values for ethyl acetate in a LDPE film and water

 

 

 

 

system.
Sample Cp(wtlwt) Ca(wt/wt) K
Blank . - 6.16 x 10-5 -
1 2.22x10“ 6.11 x 105 3.64
2 1.42x104 6.14x 105 2.31
3 1.48 x 10*4 6.11 x 10-5 2.42
Average - - 2.79
Standard deviation - - 0.74

 

* TSfTD-GC method

Table 3.1.3. Partition coefficient values for methyl ethyl ketone in a LDPE film

and water system'

 

 

 

 

 

Sample Cp (wt/wt) Ca (wt/wt) K
Blank - 3.64 x 10-5 -
1 1.95 x 105 3.61 x 10-5 0.54
2 2.65 x 10-5 3.61 x 10-5 0.73
3 1.30 x 10-5 3.62 x 105 0.36
Average - - 0.54
Standard deviation - - 0.19
* TS/TD-GC method

27

Table 3.1.4. Partition coefficient values for toluene in a LDPE film and water

 

 

 

 

 

system'
Sample Cp (wt/wt) Ca (wt/wt) K
Blank - 7.17 x 10’5 -
1 3.65 x 10*1 4.08 x 1043 89.40
2 4.33 x 10*1 4.08 x 105 106.10
3 4.48 x 10*4 4.08 x 10’5 90.88
Average - - 95.46
Standard deviation - - 9.24
* TSfTD-GC method

 

The partition coefficient (K), average partition coefficient (Kavg) and

standard deviation (0') for the above sorbates were calculated and are

summarized in Table 3.1.5.

Table 3.1.5. Partition coefficient values of the aqueous/polymer systems.

 

 

 

 

Sample Limonene Ethyl acetate Methyl ethyl ketone Toluene
1 154.18 3.64 0.54 89.40
2 207.42 2.30 0.73 106.10
3 240.96 2.42 0.36 90.88
Kavg 200.85 2.79 0.54 95.46
0‘ 43.76 0.74 0.19 9.24
* TS/TD-GC method

 

Kavg values of limonene and toluene were 200.85 and 95.46 respectively.

These values indicate a high preference for limonene and toluene to dissolve in

the LDPE rather than in the water. The Kavg values of ethyl acetate and methyl

ethyl ketone were 2.79 and 0.54, which implies that ethyl acetate and methyl

ethyl ketone were more likely to dissolve in water than in LDPE.

28

3.2 Determination of the Partition coefficient oLsaveral aqueoualpolvmer systems
Mame SPME-GC method

Sorbate concentration levels in the aqueous and in the polymer phase
were determined using the SPME-GC method. The partition coefficient values of
sorbate in a LDPE and water system were calculated (Appendix E) and
summarized in Table 3.2.1, 3.2.2, 3.2.3 and 3.2.4 for limonene, ethyl acetate,

methyl ethyl ketone and toluene respectively.

Table 3.2.1. Partition coefficient values for limonene in a LDPE film and water

 

 

 

 

system.
Sample Cp(wtlwt) Ca (wt/wt) K
Blank - 4.58 x 106 -
1 1.90x10‘4 3.32x105 57.14
2 1.99 x 10‘l 3.22 x 1045 61.93
3 1.94 x 104 3.24 x 10*5 59.85
Average - - 59.64
Standard deviation - - 2.40

 

* SPME-GO method

Table 3.2.2. Partition coefficient values for ethyl acetate in a LDPE film and water

 

 

 

 

system'
Sample Cp (wt/wt) Ca (wt/wt) K
Blank - 6.16 x 10-5 -
1 8.76 x 10-5 6.11 x 10-5 1.43
2 3.41 x 105 6.14 x 10-5 0.55
3 7.75 x 105 6.11 x 10:5 1.27
Average - - 1.09
Standard deviation - - 0.47

 

* SPME-GO method

 

~II~ (\

Table 3.2.3. Partition coefficient values for methyl ethyl ketone in a LDPE film

and water system'

 

 

 

 

Sample Cp(wt/wt) Ca(wt/wt) K
Blank - 3.64 x 10-5 -
1 2.33 x 1015 3.61 x 10-5 0.38
2 4.15 x 105 3.61 x 10-5 0.68
3 4.05 x 10-5 3.62 x 10-5 0.66
Average - - 0.58
Standard deviation - - 0.17

 

* SPME-GC method

Table 3.2.4. Partition coefficient values for toluene in a LDPE film and water

 

 

 

 

system'
Sample 0,, (wt/wt) Ca (wt/wt) K
Blank - 7.17 x 10‘5 -
1 4.58x 10*1 4.08x1OJ5 112.17
2 4.58 x 104 4.08 x 1045 112.28
3 4.58 x 104 4.08 x 1043 112.23
Average - - 1 12.23
Standard deviation - - 0.05

 

* SPME-GC method

The K, KM and standard deviation (0') for the above sorbates were

calculated and are summarized in Table 3.2.5

Table 3.2.5. Partition coefficient values of the aqueous/polymer systems'

 

 

 

 

 

 

Sample Limonene Ethyl acetate Methyl ethyl ketone Toluene
1 57.14 1.43 0.38 112.17
2 61.93 0.55 0.68 112.28
R 3 59.85 1.27 0.66 112.23
_Kavg 59.64 1.09 0.58 112.23
0' 2.70 0.47 0.17 0.05
"' SPME-GC method

30

Kavg values of limonene and toluene were 59.64 and 112.23 respectively.
These values indicate a high preference for limonene and toluene to dissolve in
the LDPE rather than in water. The K2,,g of ethyl acetate and methyl ethyl ketone
are 1.09 and 0.58, which implies that these two sorbates are more likely to
dissolve in water rather than in LDPE.

The results from the two experimental methods are summarized in Table
3.2.6.

Table 3.2.6. Partition coefficient values of aqueous/polymer systems using the

 

 

 

 

 

 

TSIT D and SPME method

- Limonene Ethyl acetate Methyl ethyl ketone Toluene
K (TS/TD) 200.85 2.79 0.54 95.46
K (SPME) 59.64 1.09 0.58 112.23
Kavg 130.25 1.94 0.56 103.85
0' 99.85 1.20 0.03 11.86

 

 

 

 

 

The partition coefficient values of the aqueous/polymer systems showed a
similar trend for both TSITD-GC and SPME-GC. Experimental error may have
cause the difference in the K values of limonene between the two methods. The
Kavg of limonene and toluene were 130.25 and 103.85 respectively. The high
partition coefficients observed with limonene and toluene indicate that these two
sorbates are more likely to be absorbed by LDPE rather than water. Conversely,
ethyl acetate and methyl ethyl ketone were highly absorbed by water rather than
LDPE due to the low partition coefficients. The Kavg of ethyl acetate and methyl
ethyl ketone were 1.94 and 0.56 respectively. These results can be expected
from the similarity of chemical structures and characteristics of the sorbates,

polymer and water. Ethyl acetate and methyl ethyl ketone are more polar than

31

 

limonene and toluene, and water is more polar than LDPE. SPME is a fast, easy
and solvent free method. Because it is a single-step method, the error from loss
of sorbate during analysis is minimized. To obtain accurate results with this
method there should be a large difference between initial concentration and final
concentration of the sorbate. The extraction time is also an important variable
affecting precision. The constancy of results is obtained by optimizing the
extraction time. The TS/T D method is a good technique for determining sorbate
concentration in the polymer. In this technique the total amount of sorbate
stripped from the polymer must be quantitatively sorbed by the trap. If a very
large quantity of sorbate is present, an overloading of the trap can occur,
resulting in sorbateloss and underestimation of the sorbate concentration in the
polymer (Gavara, 1 996).
3.3 Determination of the solubilig parameter values of aqueous/polvmer fist—ems,
using the solubilig parameter values

The solubility parameter is an important characteristic which can be used
to estimate the interaction or compatibility between product constituents and
polymeric packaging systems. To determine the three-dimensional solubility
parameter values, including the total solubility parameter (8,), as well as
dispersion (8d), polar (8p), and hydrogen bonding (8,) parameters, a software
program was written in excel (Example shown in appendix A). The equations
used for the calculation are based on Van Krevelen and Hoftyzer’s method (Van
Krevelen, 1990) and Hoy’s method (Van Krevelen, 1990). The program can be

used to calculate solubility parameter values and therefore predict the

32

compatibility between sorbates and polymers, without spending a considerable
amount of time on preliminary laboratory tests. Moreover, a database, containing
solubility parameter values for a series of sorbates and polymers, has been
created for easy reference (Appendix A).

According to Hilderbrand (Van Krevelen 1990), the cohesive energy may
be divided into three parts, corresponding to the three types of interacting forces

Econ = E. + Ep + E. (3.3.1)

where Ed, E,,, and E. are contributors of dispersion forces, and polar forces and
hydrogen bonds, respectively. For many liquids and amorphous polymers, the
solubility parameter, as defined, corresponds to the total cohesive energy, which
is dependent on the interaction between polar groups and hydrogen bonding.
Thus, the corresponding equation for the Solubility parameter is shown in the

following equation 3.3.2

2 _ 2 2 2
6: — 6d +6p +611 (3.3.2)

where 8d, 8,,, and 8h contribute dispersion forces, polar forces and hydrogen
bonds to the solubility parameter, respectively.

The method of Van Kreven and Hoftyzer predicted the solubility parameter
components from group contributions, using the following equations: (Van

Krevelen 1990)

33

ZFdi
5 = —— 3.3.3
(I V ( )

ZF2

 

00
'0

II
:I

v (3.3.4)
5,, = VZE'“ (3.3.5)

 

V
The group contributions Fdi, Fpi, and Em for a number of structural groups are
given in Table A1 (Appendix A)

The polar component is still further reduced, if two identical polar groups
are present in a symmetrical position. To take this effect into account, the value
of 8p, calculated using equation (3.3.4) must be multiplied by a symmetry factor of
0.5 for one plane of symmetry, 0.25 for two planes of symmetry, and 0 for more
planes of symmetry (Van Krevelen, 1990).

The F-method is not applicable to the calculation of 8,. It has already
been stated by Hansen (Van Krevelen, 1990) that the hydrogen bonding energy
(Em) per structural group is approximately constant. This leads to the form of
equation 3.3.5. For molecules with several planes of symmetry, 8.. = 0 (Van
Krevelen, 1990).

3.3.2 The method of Hoy (Van Krevelen, 1990) differs from the method of
Hoftyzer and Van Krevelen in many ways. Table A2. and Table A.3.(Appendix
A) shows equations incremental and values used in the method of Hoy. It
contains four additive molar functions, a number of auxiliary equations, and the

final expressions for 8.202.) and the components of 8.

34

F7 is the molar attraction function, Fp its polar component; V is the molar
volume of the solvent molecule or the structure unit of the polymer. AT is the
Lynderson correction factor for non-ideality, used in the auxiliary equations.

0f the quantities shown in the auxiliary equations, the significance is the
following: on is the molecular aggregation number, which describes the
association of the molecules; and h" is the number of repeating units per effective
chain segment of the polymer (Van Krevelen, 1990).

The results of the two algorithmic methods for estimation of the solubility
parameter and its components (Hoftyzer-Van Krevelen and Hoy) are of the same
order in accuracy (i10%). Thus, the safest way to estimate is to apply both
methods, taking the average of the results. The full equation which is used to

determine the solubility of a polymer in an organic liquid is:

A5 = [(6d,p - 6,1,5 )2 + (613,1) - 6P15 )2 + (6h,p — 511’s )zr/ 2 (3.36)

For good solubility '56 must be smaller than 5 (s 5) (Van Krevelen, 1990).

The solubility parameter program was used to calculate the three-
dimensional (3-D) solubility parameter values of sorbates in LDPE as shown in
Table 3.3.1. In Table 3.3.2 the solubility parameters of the sorbates/LDPE
system are presented. The structural details of the sorbates and polymer
material are shown in Appendix F.

The solubility of a given polymer in'various solvents is largely determined
by its chemical structure. Besides the chemical structure, also the physical state

of a polymer is important for its solubility properties. Crystalline polymers are

35

relatively insoluble and often dissolve only at temperatures slightly below their

melting points (Van krevelen, 1990).

Table 3.3.1. Three-dimensional (3-D) solubility parameters of LDPE and sorbates

calculated using the solubility parameter program

 

 

 

 

 

 

 

Sorbates/Polymer delta total (81) delta dispersive (8d) delta polar (8p) delta hydrogen (8n)
(J/cm3)"2 (J/cm3)"2 (J/cm3)”2 (J/cm3)"2

LDPE (1) 18.01 18.01 0.00 0.00
LDPE (2) 17.74 17.74 0.00 0.00
limonene (I) 18.31 15.84 5.77 7.13
limonene (2) > 16.40 16.40 0.00 0.00
ethyl acetate (1) 21.77 14.22 9.19 13.68
ethyl acetate (2) 18.22 15.34 5.01 8.46
methyl ethyl ketone 11) 22.26 14.11 9.47 14.39
methyl ethyl ketone (2) 18.45 15.63 8.60 4.73
toluene (1) 20.68 16.85 8.16 8.78
toluene (2) 17.44 17.41 1.04 0.00
water 48.00 13.30 31.30 34.20

* (1) Hoy method

(2) Van Krevelen and Hoftyzer method

Table 3.3.2. Solubility parameter values of the sorbate/LDPE systems

 

 

 

 

 

 

Sorbates A8 between LDPE (chm3)1’2 A8 between water (J/cm3)1’2

Limonene (1) 9.43 37.30
Limonene (2) 1.34 46.46
Ethyl acetate (1) 16.91 30.18
Ethyl acetate (2) 10.12 36.85
Methyl ethyl ketone 11) 17.66 29.49
Methyl ethyl ketone (2) 10.03 37.28
Toluene (I) 12.05 34.58
Toluene (2) 1.09 45.85
* (1) Hoy method

(2) Van Krevelen and Hoftyzer method

36

3.4 Correlation between the solubility parameters using Hoy method and partition
coefficient (K) of the sorbates in a two-phase, agueous/polymer system

The partition coefficients (K) and solubility parameter values (A8) of

 

aqueous/polymer systems are summarized in Table 3.4.
Table 3.4. Partition coefficients and solubility parameters using Hoy method of

the aqueous/polymer systems

 

 

 

Limonene Ethyl acetate Methyl ethyl ketone Toluene
K (1) 200.85 2.79 0.54 95.46
K12) 59.64 1.09 0.58 112.23
K13) 130.25 1.94 0.56 103.85
A8 (J/cm3)"2 9.43 16.91 17.66 12.05

 

* ( 1) K average using TSITD-GC method
(2) K average using SPME-GO method
(3) K average from TSfT D and SPME method

The solubility parameter value of limonene was 9.43 (chm3)"2. This
indicates that there is a chemical similarity between limonene and LDPE.
Therefore, a high partition coefficient should be expected and the Kavg of
limonene/LDPE was 130.25. For toluene a similar trend was observed. Toluene
had a solubility parameter value of 12.05 (J/cm3)"2. Therefore, a substantial
amount of toluene was expected to be sorbed by LDPE, which was reflected in a
Kavg of 103.85. Conversely, the solubility parameter values of ethyl acetate and
methyl ethyl ketone were 16.91 (chmt‘)"2 and 17.66 (J/cm3)"2 respectively, which
implies chemical difference between both ethyl acetate and methyl ketone, and
LDPE. The low partition coefficient is expected. The Kavg of ethyl acetate/LDPE
and methyl ethyl ketone/LDPE were 1.94 and 0.96 respectively.

From the results generated, a correlation between the partition coefficients

of an aqueous/polymer system from the TS/TD-GC and the SPME-GC methods,

37

and solubility parameter values can be established. The correlation was

determined using exponential regression as shown in Figure 3.4.

300

2504

. y = 149826e0'6793 *
200 _. R2 = 0.9328

150_

1003

Partition coefficient (K)

504

 

 

0 . r . r: .
0 5 10 15 20

Solubility parameter (JIcm3)1I2

it

Figure 3.4. Correlation between partition coefficients using the TSITD-GC and

SPME-GC method and solubility parameters using Hoy method

3.5 Correlation between the solubility parameters using Hoftyzer and Van
Krevelen method and partition coefficient (K) of the imates in a two-phase,

agueous/polvmer system

The partition coefficients (K) and solubility parameter values (A8) of

aqueous/polymer systems are summarized in Table 3.5.

38

Table 3.5. Partition coefficients and solubility parameters using Hoftyzer and Van

Krevelen method of the aqueous/polymer systems

 

 

 

Limonene Ethyl acetate Methyl ethyl ketone Toluene
K (1) 200.85 2.79 0.54 95.46
K (2) 59.64 1.09 0.58 112.23
Kl3) 130.25 1.94 0.56 103.85
A8 (J/cm3)"2 1.34 10.12 10.03 1.09

 

* (1) K average using TS/TD-GC method
(2) K average using SPME-GC method
(3) K average from TS/T D and SPME method

The solubility parameter values between limonene and toluene and LDPE
are 1.34 and 1.09 respectively. This indicates high compatibility between both
limonene and toluene and LDPE. Therefore, the partition coefficient values of
limonene and toluene are 13.025 and 103.85 respectively. On the other hand,
solubility parameter values of ethyl acetate and methyl ethyl ketone are 10.12
and 10.13 respectively. This effect low partition coefficient values of 1.94 and
0.96 for ethyl acetate and methyl ethyl ketone respectively.

From the data, a correlation between partition coefficient values and
solubility parameter values using Hoftyzer and Van Krevelen method can be

established as shown in figure 3.5.

39

Partition coefficient (K)

 

 

o 2 4 6 3 1o 12
Solubility parameter (JIcm3)1I2
Figure 3.5. Correlation between average .of partition coefficients using the

TSITD-G0 and SPME-GC method and solubility parameters using Hoftyzer and

Van Krevelen method

40

Chapter 4

SUMMARY AND CONCLUSION

The partition coefficient (K) is defined as the equilibrium concentration of
sorbate in the polymer phase [Cp] divided by the equilibrium concentration of
sorbate in the aqueous phase [C2]. The partition coefficient results of
aqueous/polymer systems were generated using two experimental methods,
TSITD-GC and SPME-GC. The TS/T D methodology, which includes GC
analysis, was used to directly determine the sorbate concentration in the
polymer. In this technique the total amount of sorbate stripped from the polymer
sample must be quantitatively sorbed by the trap (Gavara, et al., 1995). The K
values of limonene, ethyl acetate, methyl ethyl ketone and toluene using TSITD-
GC system were 200.85, 2.79, 0.54 and 95.46 respectively. The SPME method
is a newer technique and can be used to determine sorbate concentration in the
aqueous phase. It is a relatively easy and fast way compared to the solvent
extraction analysis. The K values of limonene, ethyl acetate, methyl ethyl ketone
and toluene using SPME-GO system were 59.64, 1.09, 0.58 and 112.23
respectively. The partition coefficient values from the two experimental methods
had a high degree of correlation. The solubility parameter value can be used to
estimate the solubility of a sorbate in a polymer, and is a good indicator of the
chemical compatibility between a sorbate and a polymer. The solubility
parameter values using Hoy method for limonene, ethyl acetate, methyl ethyl

ketone and toluene were 9.43, 16.91, 17.66 and 12.05 (JIcm3)1’2 respectively.

41

The solubility parameter values using Hoftyzer and Van Krevelen method are
1.34, 10.12, 10.03 and 1.09 (.l/cm3)“2 for limonene, ethyl acetate, methyl ethyl
ketone and toluene respectively.

Values of A8 determined using the solubility parameter program and K
values from two experimental methods for each sorbate were compared.
Chemical similarity between sorbate and polymer was found, when the solubility
parameter value was equal or less than 5 and thus, a high partition was achieved
as indicated by a high value for the partition coefficient. 0n the other hand, low
solubility was found with a low partition coefficient value. In this research a
correlation between partition coefficient values and solubility parameter values
for the compatibility of sorbates/polymer system was established. An exponential
regression was used to determine the correlation between solubility parameter
values and partition coefficient values. The solubility parameter value is a useful
indicator of a sorbate/polymer system. It can be used to help select the most
suitable packaging material for a given package-product-environment system.
Also it provides an alternative to accelerated storage studies for evaluating

candidate-packaging systems.

42

APPENDICES

43

APPENDIX A

 

3:3 Microsoft Excel - Solubility Parameterxls

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

J'Eietdtuewtnsertrwmatlodsoatamowueb Aflx
IoenaletttvlselnvemtlImmllzv ’.
A2 . s Solubility parameter calculation by method of Hoy
A I a (1985,1989)

1

2 Solubility parameter calculation by method of Hoy (1985,1989)
3 Fill in the blue color zone -

4 EnterIforpolymer,llforsorbates I 1 I Calculatill
5 Structural Number Of Valent groups insaturated ring Ftifi I Fpi___I
5 Groups Group bi- I tri- I tetra- (Imam/mull (Jem’jmimol

7 -Cl13 I U 0 0 303.5 0

8‘ -CH2- 1 [I 0 0 269 0

9 >CH- 1 I] 0 0 175 0
..fl >C< 0 0 U 0 0 0

11 =Cl-l2 0 U I] 0 I] 0

I2 =CH- 0 0 0 U 0 0

l3_ =C< 0 0 0 0 0 0

14 CH aromatic 0 0 I] 0 0 El

15 Caromatic 0 0 0 0 El 0

1_B_ -HC=0 0 0 U 0 0 0

17 >C=0 [J 0 0 0 U [I

18 -000H 0 U 0 I] 0 0

i -000- I 0 0 0 640 528
A-CO—O—CO 0 [I 0 0 0 0

21 -CN @Bonds) 0 0 0 0 0 0
_2;-N=0=0 U 0 0 0 0 0

23 HCON< 0 0 0 I] 0 0

24 -CON|-l2 0 0 0 0 0 0 .

I 1 SheeOJ Mfiteetslflnetflml 1] I LII-J

Ready II I l I mu l l— 2,

 

Figure A.1 Example of solubility parameter program of Hoy method

 

B Hicrosoll Excel - Solubility Parameter.xls
Iltietdttnwtmtromatloolsoatamueb

 

 

_._|l_9_|x
loeualemlee|mgztglmpp 111,. .'

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

A82 ' - Solubility parameter calculation by method of
A I B - Hoftyzer and Van Krevelen (1976)

82 Solubility parameter calculation by method of Hoftyzer and Van Krevelen
B3

84 I Calculation values Group contributionsx
85 Structural Number of F; Fri Ea F; F“

$ Group Group .cmfimim .cmfimlm Jimol (J.cm§"2!mol (Jcmajmlmol

87 -CH3 0 0 0 0 420 0

ea -CH2- ' 2 540 0 270

89 >Cl-l 0 0 0 0 80 0

90 >C< 0 0 0 0 -70 0

9_I =CH2 o o u u loo 0

g =cn o o o o zoo o
£=C< 0 0 0 0 70 0

94 O o u o o 1520 o

95 :8 0 0 0 0 1430 110

% 0 0 0 0 1270 110

974$ 0 0 0 0 220

in o u o o 450 550

99 -Br 0 0 0 0 550

10] -CN 0 0 0 0 430 110] -
101 -0H 0 0 0 0 210 500

102 -0- 0 0 0 0 1m 40]

fl -COII 0 0 0 0 470 3]]

104 -CO- 0 0 0 0 290 770

105 -000H 0 0 0 0 530 420 ,
. u Sliced Since MXMKMTSbeeItI l LII-l
Read) I l_l l_l_l\l_Ml_l_l_ /,,

 

Figure A.2 Example of solubility parameter program of Hoftyzer and Van

Krevelen method

45

 

Table A1. Solubility parameter component group contributions (Method Hoftyzer-

Van Krevelen) (Van Krevelen 1990)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Structural Fa, Fp, Em
Group (J.cm°)"2/mol (J.cm3)"2/mol J/mol
-CH;, 420 o 0
-CH2- 270 o o
>CH- 80 0 0
>C< -70 0 0
=CH2 400 0 0
=CH- 200 0 0
=C< 70 0 0
Q 1620 0 o
:9 1430 110 0
©- 1270 110 o
-F 220 - -
-Cl 450 550 400
-8r 550 - -
-CN 430 1100 2500
-OH 210 500 20000
-O- 100 400 3000
-COH- 470 800 4500
-C0- 290 770 2000
-COOH 530 420 10000
-C00- 390 490 7000
HCOO- 530 - -
-NH2 280 - 8400
-NH— 160 210 3100
-N< 20 800 5000
-N02 500 1070 1500
-5. 440 - -
-P04- 740 1890 13000
Ring 190 - -

 

46

 

Table A2. The equations to be used in Hoy’s system for estimation of the

solubility parameter and its components (Van Krevelen, 1990).

 

 

 

 

 

 

 

 

 

Formulae Low-molecular Liquids (Solvents) Amorphous Polymers
Additive F1 = ZNiFli Fl = XNiFli
Molar H. = ZNini H, = ZNini
functions V = ENiVi V = ENiVi
AT = ZNiAri AIP)1,1= ENiAIPITi
(P)
Auxiliary Log 3 = 3.39 [Ti] 0.1585 - logV up, = 777Ar
cr
equations Tb = boiling point; Tcr = critical temp.
_ 0.5
[l] = 0.567 +Ar- (Ar)2 " = W
Tc, A7.
(Lynderson equation)
Ex ressions for 8 and ‘—
p = Ft+B 3:277 & Ft+B/n
8-cornponents V
1 2 1 2
- 1 FD / _ 1 Fp /
5p — — 5p ' 5i — _
or Ft + B or Ft -l- B/I'I
1/2 1/2
(NotethatFimustbe 5 _ 5 a_1 8 8 a(P) -1
combinedwithaBase h I a I h - ' 610’)
value; 8 for liquids and /2 /2
- 2 2 2 .. 2 2 2
d Ist 50 SJ 5" ' (5t ‘59‘5h)|

B/fi for polymers

 

47

Table A.3. Values of increments in Hoy’s system for the molar attraction function

 

 

 

 

 

 

 

Grows Fu Fpi Vi 4811' Am“ Grolps FU ij Vi Ari' A‘P’m
(J.cm3)mlmol ans/moi - - (J.cm3)"2/mol cm3/mol - -
.0113 303.5 0 21.55 0.023 0.022 -0H(H-bond) 485 485 10.55 0.082 0.034
cu:- 259 0 15.55 0.02 0.02 -0H(Prim.) 575 575 12.45 0.082 0.049
>CH- 175 0 9.55 0.012 0.013 -0H(Sec.) 591 591 12.45 0.082 0.049
>c< 55.5 0 3.55 0 0.04 —0H (Tort) 500 500 12.45 0.082 0.049
=CH2 259 57 19.17 0.018 0.019 -0H (Phenolic) 350 350 12.45 0.031 0.005
=CH- 249 59.5 13.18 0.018 0.0185 -0- (Ether) 235 215 5.45 0.021 0.018
=c< 173 53 7.18 0 0.013 -0-(Acetal) 235 102 5.45 0.018 0.018
CHarornatic 241 52.5 13.42 0.011 0.018 -0-(Epoxide) 351 155 5.45 0.027 0.027
Canornatic 201 55 7.42 0.011 0.015 -NH2 454 454 17 0.031 0.035
-HC=0 500 532 23.3 0.048 0.045 -NH- 368 368 11 0.031 0.0275
>c=o 538 525 17.3 0.04 0.04 >N- 125 125 12.5 0.014 0.009
-COOl-I 555 415 25.1 0.039 0.039 -s- 428 428 18 0.015 0.032
-000- 540 528 23.7 0.047 0.05 -F 845 73.5 11.2 0.018 0.005
-co-o-co- 1150 1150 41.0 0.085 0.086 -Cl(Prim.) 419.5 307 19.5 0.017 0.031
can 725 725 23.1 0.05 0.054 -Cl(Sec.) 425 315 19.5 0.017 0.032
-N=C=O 735 8.2 25.9 0.054 0.054 -Cl (Aromatic) 330 81.5 19.5 0.017 0.025
HCON< 1020 725 35.8 0.052 0.055 <01: (Twinned) 705 572 39 0.034 0.052
-CONH2 1200 900 34.3 0.071 0.084 -Br(Aliphatic) 528 123 25.3 0.01 0.039
-CONH- 1131 895 28.3 0.054 0.073 -Br(Aromatic) 422 100 25.3 0.01 0.031
~000NH- 1255 890 34.8 0.078 0.094
Configurations F..- 5,, vi Ar; A“... Configualions n. F...- vi Ar: A‘P’TL,
Conjugation
Basevalue(B) 277 - - - - _ , 47.5 -19.8 - 0 0.0035
Isomensm
Ring size cis -14.6 -14.6 - -0.001
(non-aromatic) trans -27.6 -27.6 - -0.002
Aromatic
4-membered 159 203 - 0 0.012 ..
stbstltutlon
5-rnembered 43 85 - 0 0.003 otho 20.2 -13.3 - 0 0.0015
6-membered -48 51 - 0 ' meta 13.5 -24.3 - 0 0.001
0.0035
7-membered 92 0 - 0 0.007 para 83 -34 - 0 0.005

 

* For bi-, tri- and tetra-valent groups in saturated rings the AT-values must be multiplied by a

factor 2I3.

48

Table A4. Database of the solubility parameter values of sorbates from the

solubility parameter program

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

|s°rbat°s (052%)"? (J/ég: )“2 (015%)"? nigh“?
Hydrocarbons

hexane (1) 148-149 14.80 0.00 0.00
hexane (2) 18.61 15.75 0.00 9.92
hexane (3) 14.71 14.71 0.00 0.00
hexane (4) 16.66 15.23 0.00 4.96
heptane (1) 15.20 15.20 0.00 0.00
heptane (2) 18.44 15.80 0.00 9.52
heptane (3) 14.95 14.95 0.00 0.00
heptane (4) 16.70 15.37 0.00 4.76
octane (1) 15.60 15.60 0.00 0.00
octane (2) 18.31 15.79 0.00 9.27
octane (3) 15.14 15.14 0.00 0.00
octane (4) 16.73 15.47 0.00 4.64
yclohexane (1) 15.70 15.70 0.00 0.00
cyclohexane (2) 19.75 15.75 2.91 1 1 .56
cyclohexane (3) 16.75 16.75 0.00 0.00
cyclohexane (4) 18.25 15.25 1.45 5.78
benzene (1) 18.5-18.8 176-185 1.00 2.00
benzene (2) 21 .40 16.92 8.93 9.58
benzene (3) 18.27 18.23 1 .24 0.00
benzene (4) 19.84 17.58 5.08 4.79
methylbenzene (toluene) (1) 18.30 17.70 1 .40 2.00
methylbenzene (toluene) (2) 20.68 15.85 8.16 8.78
methylbenzene (toluene) (3) 17.44 17.41 1 .04 0.00
methylbenzene (toluene) (4) 19.05 17.13 4.50 4.39
1,2-dimeth lbenzene

04mm) {1) 18.40 168-176 1.00 1.00
1,2-dimeth lbenzene

(”fie”) {2) 20.34 15.92 7.42 8.51
1,2-dimeth lbenzene

(o-xxlene) {3) 19.09 19.07 0.91 0.00
1,2-dimeth lbenzene

(041509?” 19.71 17.99 4.17 4.25
1,3-dimeth lbenzene

(mmeneym 18.00 157-174 1.00 1.00

 

49

 

Table A4. (Cont’d)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1.3-dinethylbenzene
(tn-xylene) (2) 20.28 16.91 7.30 8.48
1 ,3-dirnethylbenzene
m—xylene) (3) 18.74 18.72 0.90 0.00
1.3-dimethylbenzene
m-xylene) (4) 19.51 17.81 4.10 4.24
1’4'd'mmy'bemm 17.9—18.0 15.5-17.3 1.00 1,00
xylene) (1)
1 ,4-dimethylbenzene
xyleng (2) 20.90 17.52 7.31 8.74
1 ,4-dimethylbenzene
-mene) (3) 18.68 18.65 0.89 0.00
1,4-dirnethylbenzene
xylene) (4) 19.79 18.09 4,10 4,37
ethylbenzene (1) 17.9-18.0 167-178 0.60 1,40
lethvlbenzene (2) 20.21 15.90 7,58 8.08
[ethylbenzene (3) 18.89 18.87 0.90 0,00
@wbenzene (4) 19.55 17.88 4.24 4.04
thenylbenzene
Emilie) (1) 180/190 168-186 1.00 4,10
thenylbenzene
thenylbenzene
rstyrene) (3) 19.36 19.33 0.96 0.00
thenylbenzene
Estyrene) (4) 19.93 17.91 4.98 4,10
lHydrocarbons, haloginated
dichloromethane
(methylene chloride) (1) 19.90 174-182 6.40 6.10
dichloromethane
(methylene chloride) (2) 2293 12-95 1189 14.72
dichloromethane
methylene chloride) (3) 22.38 18.40 12.23 3.55
dichloromethane
methylene chloride) (4) 2255 1558 12-06 9.13
' hloromethane
chloroform) (1) 18.9-19.0 177-181 3.10 5.70
' hloromethane
chloroform) (2) 23.18 12.81 14.37 12.91
' hloromethane
chloroform) (3) 21.92 17.95 1 1 .96 3.88

 

 

 

 

 

50

 

Table A4. (Cont’d)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

' hloromethane
chloroform) (4) 22.55 15.38 13.16 8.40
achloromethane
trachloromethane
carbon tetrachloride) (2) 21.49 1 1.32 15.52 9.64
trachloromethane
carbon tetrachloride) (3) 21 '64 1794 1 1 ~40 4-07
tetrachloromethane
carbon tetrachloride) (4) 2155 14-53 13-46 6.85
chloroethane
chloroethane
(ethyl chloride) (2) 22.54 14.96 8.57 14.51
chloroethane
chloroethane
ethyl chloride) (4) 19-98 1526 8.04 8.42
1 ,2-dicloroethane
(ethylene chloride) (1) 20.0-20.1 174-188 5.30 4,10
1,2—dicl0roethane
(ethylene chloride) (2) 2359 15-21 1 1 .77 13.82
1 ,2-dicloroethane
ethylene chloride) (3) 2103 1829 9-33 3.19
1 ,2-dicloroethane
ethylene chloride) (4) 2236 16-75 10-83 8.50
1,1-dicloroethane _
ethylidene chloride) (1 ) 183° 153° -
1,1-dicloroethane
ethylidene chloride) (2) 2085 13-43 10-77 1 1 .75
1,1-dicloroethane
(ethylidene chloride) (3) 19°25 16'61 9-23 3.03
1,1-dicloroethane
1,1,2-trichloroethane (1) 19.7-20.8 18,30 - ,_
1,1,2-trichloroethane (2) 22.08 13.77 13.12 1 1,23
1 ,1,2-trichloroethane (3) 21 .38 18.39 10.30 3.60
1,1,2-trichloroethane (4) 21.73 16.08 1 1.71 7,42
1,1,1-trichl0r0ethane (1) 17.50 16.6-16.9 4.30 2,00
1,1,1-trichl0roethane (2) 22.78 14.52 14.05 10.52
1 .1,1-trichlor0ethane (3) 19.66 16.88 9.46 3,45

 

 

51

 

Table A4. (Cont’d)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1,1,1-lrichloroethane (4) 21.22 15.70 11.76 6.99
1,1,2,2-trichlor0ethane (1) 1 9.9-20.2 18.70 - -
1,1,2,2-trichloroethane (2) 20.99 12.54 14.18 9.08
1,1,2,2-tn'chloroethane (3) 21 .78 18.68 10.48 3.91
1,1 ,2,2-01'chl0r0ethane (4) 21.39 15.61 12.33 6.49
1-chloropropane _ _
n-propylchloride) (1 ) 17°40 159°
1-chl0r0propane
njlropylchloride) (2) 21 .32 15.41 7.69 12.57
1-chloropropane
n- ropylchlon'de) (3) 17.28 15.98 6.23 2.13
1-chloropropane
n— p re 9716111 0 rid e) (4) 19.30 15.69 6.96 7.35
1-chlorobutane
n-butyl chloride) (1) 17.30 16.1-16.3 5.50 2.10
1-chlor0butane
(n-b U171 chloride) (2) 20.60 15.68 7.09 1 1 .33
1-chlorobutane
n-butyl chloride) (3) 16.99 16.04 5.25 1.95
1-chl0robutane
n-butyl chloride) (4) 18.80 15.86 6.17 6.64
chlorobenzene (1) 19.5-19.6 188-190 4.30 2.10
chlorobenzene (2) 21.41 17.18 9.34 8.73
chlorobenzene (3) 19.40 18.49 5.52 1 .98
chlorobenzene (4) 20.40 17.83 7.43 5.36
bromobenzene (1) 21.70 20.50 5.50 4.10
bromobenzene (2) 21 .09 17.85 9.67 5.70
bromobenzene (3) 18.93 18.90 1 .05 0.00
bromobenzene (4) 20.01 18.38 5.36 2.85
1,1,2 trichloro-1,2,2-
' uoroethane 14.80 14.50 1 .60 0.00
freon113) (1)
1,1,2 momma-1,2,2-
' uoroethane 41.06 30.65 18.73 19.89
freon113) (2)
1,1,2 trichl0r0-1,2,2-
' uoroethane 17.80 15.61 7.95 3.16
freon113) (3)
1,1,2 trichlor0-1,2,2-
' uoroethane 29.43 23.13 13.34 1 1 .53

freon113) (4)

 

 

 

 

 

52

 

Table A4. (Cont’d)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Ethers

Egfieg‘flfi (1) 152-155 14.40 2.90 5.10
$33933 (2) 20.55 15.02 5.82 12.75
mgfg‘tfigf) (3) 15.72 14.25 3.85 5.38
fifig‘flflg (4) 18.13 14.54 4.83 9.07
1'P'°°°"Yp’°pa"e 14.10 - - -
dlpropyl ether) (1)

$331?ng 19.54 15.32 5.05 11.20
($333281???) 15.54 14.55 2.88 4.55
iriri'o‘iil‘i'i‘é‘iiifi 17.59 14.93 3.97 7.93
zagziggngfflm 14.40 13.70 - -
21.?°pmp°"yp'°pa"e 18.59 14.87 5.05 9.95
dllsopropyl ether) (2)

iiifiir'é‘ififhiiia 14.81 13.79 2.84 4.52
flaggmflgfifi 15.70 14.33 3.95 7.28
3:337:23:ny 145-159 15.20 - -
‘ég‘fig’l‘fififin 19.13 15.37 4.50 10.47
1&‘m‘fi‘gygl 15.87 15.12 2.35 4.21
‘Jfim‘gfim 17.50 15.24 3.43 7.34
“333??“ 17.40 15.10 1.80 8.50
gfhtzfa’ggmam 25.21 15.99 7.59 18.45
gtggggfl‘m 18.03 14.74 5.35 8.22
3:231”ng 22.12 15.86 5.98 13.34

 

 

 

 

 

53

 

Table A4. (Cont’d)

 

methoxybenzene

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(“mom (1) 19.5/20.3 17.80 4.10 5.80
methox benzene

anisole‘; (2) 22.90 17.31 9.39 11.58
methox benzene

a "i s 0' e1; (3) 22.75 21.81 3.82 5.25
methox benzene

mime); (4) 22.83 19.55 5.50 8.47
2,2'-dichlorodiethyl ether (1) 21.1-21.2 172-183 9.00 3.10
2,2'-dichlorodiethyl ether (2) 22.57 15.27 11.13 12.52
2,2‘-dichlorodiethyl ether (3) 20.10 17.77 7.47 5.70
2,2'—dichlorodiethyl ether (4) 21.38 15.52 9.30 9.11
1-chloro-2,3-e 0x r0 ane

@ichlomhydr‘i’n) (1"; 1’ 21.90 19.00 10.20 3.70
1-chl0ro-2,3—e 0x ane

e01 cm 0,th d r‘ih) {2‘3” 25.50 16.85 10.02 17.97
1-chlor0-2,3-e 0x 0 ane

epichlomhydr‘i’n) (’5' 9 18.47 14.92 8.67 5.58
1-chlor0-2,3-e 0x 0 ane
(epichmhydr‘i’n) a? 9 22.53 15.89 9.35 12.28
LEsters
[ethyl forrnate (1) 18.70 15.50 7.20 7.50
[ethyl formate (2) 22.38 14.13 9.1 1 14.78
Qty: formate (3) 19.59 15.22 5.24 1 1.17
'3ny formate (4) 20.99 14.57 7.17 12.97
propyl formate (1) 19.60 15.00 - -

ropylforrnate (2) 21.38 14.60 8.35 13.20

ropyl fonnate (3) 18.79 15.24 4.30 10.1 1

ropyl formate (4) 20.08 14.92 6.32 1 1 .66
methyl acetate (1) 18.70 15.50 7.20 7.50
methyl acetate (2) 22.81 13.75 10.01 15.21
methyl acetate (3) 19.15 15.51 6.18 9.39
methyl acetate (4) 20.98 14.53 8.09 12.30
ethyl acetate (1) 18.50 15.20 5.30 9.20
ethyl acetate (2) 21.77 14.22 9.19 13.58
[ethyl acetate (3) 18.22 15.34 5.01 8.45

thyl acetate (4) 20.00 14.78 7.10 11.07
propyl acetate (1) 179180 15.60 - -

ropyl acetate (2) 21.05 14.53 8.52 12.55

 

 

 

 

 

 

 

Table A4 (Cont’d)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

propyl acetate (3) 17.75 15.37 4.25 7.80
propyl acetate (4) 19.41 14.95 6.39 10.22
Eopropyl acetate (1 ) 172-176 144-149 4.50 8.20
{sopropyl acetate (2) 20.46 14.25 8.52 11.95
Eopropyl acetate (3) 17.21 14.79 4.19 7.74
isoprcpyl acetate (4) 18.83 14.52 6.36 9.85
butyl acetate (1) 173-174 15.70 3.70 5.40
butyl acetate (2) 20.55 14.71 7.95 11.93
butyl acetate (3) 17.52 15.49 3.72 7.29
butyl acetate (4) 19.03 15.10 5.84 9.51
isobutyl acetate (1) 170/172 15.10 3.70 7.50
(sobutyl acetate (2) 20.83 14.74 8.19 12.22
@5081 acetate (3) 15.08 13.87 3.57 7.24
(Ehutyl acetate (4) 18.45 14.31 5.93 9.73
[Ethyl acetate (1) 17.10 15.30 3.10 7.00
Eyl acetate (2) 20.16 14.82 7.48 11.43
hmyl acetate (3) 17.29 15.53 3.29 5.85
(amyl acetate (4) 18.72 15.17 5.39 9.15
isoamyl acetate (1) 17.00 15.30 3.10 7.00
soamyl acetate (2) 19.70 14.63 7.49 10.85
isoamyl acetate (3) 15.91 15.12 3.25 5.83
isoamyl acetate (4) 18.30 14.87 5.38 8.84

thyl lactate (1) 20.51216 15.00 7.50 12.50
Ehyl lactate (2) 24.53 12.56 11.07 17.93
(ethyl lactate (3) 22.74 15.62 6.11 15.35
Ethyl lactate (4) 23.53 14.09 8.59 15.64
butyl lacetate (1) 192/198 15.70 6.60 10.20
butyl lacetate (2) 22.87 13.05 9.81 16.02
butyl lacetate (3) 20.94 15.43 4.64 13.37
butyl lacetate (4) 21.90 14.24 7.22 14.59
2-eth0x eth | acetate

ceuosofve game) (1) 19.70 15.90 4.70 10.60
2—ethox eth l acetate

ceuoso‘I've aycetate) (2) 22.45 15.13 8.83 14.05
2-ethox eth l acetate

ceuosone gcetate) (3) 18.53 15.76 4.56 8.58
“WWW" “em 20.49 15.44 5.74 1 1.31

 

cellosolve acetate) (4)

 

 

 

 

 

55

 

Table A4. (Cont’d)

 

diethylene glycol,
hionothyl ether, acetate
(carbitol acetate) (1)

17.41193 16.20

 

diethylene glycol,

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

methyl propyl ketone) (4)

 

 

 

 

monothyl ether. acetate 21.21 14.11 8.97 13.04
(carbitol acetate) (2)

diethylene glycol,

”100011171 ether, acetate 18.61 15.92 4.29 8.63
(carbitol acetate) (3)

diethylene glycol,

monothyl ether, acetate 19.91 15.02 6.63 10.84
carbitol acetate) (4)

etones and aldehydes

Q-propanone (acetone) (1) 200205 15.50 10.40 700
2-Propanone (acetone) (2) 23.54 13.55 10.37 1522
2-propanone (acetone) (3) 19.36 1 5.41 10.50 5,22
2-propanone (acetone) (4) 21.45 14.48 1043 10,72
2-butanone

(methyl ethyl ketone) (1) 19.00 15.90 9.00 5.10
2-butanone

2—butanone

(methyl ethyl ketone) (3) 18°45 15-53 8-60 4.73
2-butan0ne

(methyl ethyl ketone)(4) 2°35 “-87 9-03 9.56
3-pentanone

diethyl ketone) (1) 180/181 15.70 - -
3-pentan0ne

diethyl ketone) (2) ”'42 14°46 8-75 13.17
B-pentanone

(diethyl ketone) (3) 17.96 15.82 7.30 4,35
3-pentanone

diethyl ketone) (4) 1959 1 5-14 3-02 8. 76
2-pentanone

2-pentanone
lQnethyl propyl ketone) (2) 21 '42 14-46 8-75 13.17
Q—pentanone

(methyl propyl ketone) (3) ”'87 15°74 7-25 4-34
2-pentan0ne 1 9.65 15.10 8.00 8.75

 

56

 

Table A4. (Cont’d)

 

2-hexanone

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

mew, my, ketone) (1) 17.47177 15.90 - -
Exafiunfy, ketone) (2) 20.82 14.68 8,15 12.32
22133.23; ketone) (3) 17.31 15.65 6,21 4,02
fifi'fl; ketone) (4) 19.07 15.15 713 8,17
mmfimfifmfi) (1) 17.27175 15.30 6.10 4,10
nehhyiéifi’ffii'é‘igia (2) 2027 14-43 8-15 1 1.68
me,§‘,’,';§':f,;}ig°,gfig 13) 16.90 15.21 6.17 4,00
14$:le :sitftftglti‘etgh) (4) 18-58 14-82 7-16 7.84
263353303131?” 16.01167 15.90 3.70 4.10
zafg‘gfi‘mg’gw 18.99 14.61 5.84 10,02
zgigmttflzmgm 16.10 15.13 4.36 3.37
fafigflmgfigmfm 17.55 14.87 5.50 659
m'gfigyggggfimm 18.4/188 15.30 720 5,10
mtgg‘yygfidzqumm 20.99 14.59 9,59 1155
mtgg‘ylgjdgj"(§tme 17.70 15.84 6,70 4,17
”'m‘gzg‘yygfimflm 19.34 15.21 8,14 7,91
1:233:30??? 19.80 175-185 8.60 3.70
"3,123,123,21ng 22.27 15.54 11.59 10.96
figggfigflngj‘fge 19.88 18.28 6,64 413
ggmmfime 21.07 16.91 9.12 7,55
lethanal (acetaldehyde) (1) 20.20 14.70 8,011 1130
kmanal (acetaldehyde) (2) 26.32 12.80 11.59 19.86

 

 

 

 

 

57

 

Table A4. (Cont’d)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

[ethanal (acetaldehyde) (3) 23.08 15.82 14.22 8.94
lethanal (acetaldehyde) (4) 24.70 14.31 12.91 14.40
butanal (butyraldehyde) (1) 17.10 14.70 5.30 7.00
butanal (butyraldehyde) (2) 22.53 14.13 9.45 14.93
butanal (butyraldehyde) (3) 19.89 16.20 9.07 7.14
butanal (butyraldehyde) (4) 21.26 15.17 9.26 11.03
benxenecarbonal

benzaldehyde) (1) 19.2-21.3 182-187 8.60 5.30
benxeneca‘bond

(benzaldehyde) (2) 23.34 15.30 12.45 12.47
benxenecarbonal

benzaldehxde) (3) 21.49 18.80 7.99 5.67
benxenecabonal

(benzaldehyde) (4) 22.41 17.05 10.22 9.57
Alcohols

methanol (1) 29.2-29.7 15.20 12.30 22.30
methanol (2) 33.09 12.17 1 1.13 28.69
methanol (3) 29.83 15.57 12.36 22.23
methanol (4) 31.46 13.87 11.74 25.46
(ethanol (1) 26.0-26.5 15.80 8.80 19.50
Ethanol (2) 27.95 12.74 9.63 22.93
gland (3) 25.55 15.41 8.56 18.51
Finanol (4) 26.75 14.08 9.10 20.72
1-propanol (1) 24.4-24.5 15.90 6.80 17.40
1-propanol (2) 25.33 13.15 8.66 19.84
1-propanol (3) 23.07 15.19 6.49 16.1 1
1-propanol (3) 23.61 15.65 6.69 16.36
1-propanol (4) 24.00 14.55 7.28 17.44
2-propan0l

isopmpy' am 0|) (1) 23.60 15.80 6.10 16.40
2-propanol

Usogropyl who” (2) 24.40 12.74 8.62 18.94
2-propan0l

'someYI who" (3) 22.84 14.76 6.53 16.15
2-propanol

(lsoprowl who" (4) 23.52 13.75 7.58 17.55
1-butanol (1) 23.1/23.3 15.00 5.70 15.80
1-butanol (2) 23.75 13.44 7.94 17.90
1-butanol (3) 22.27 15.74 5.45 14.78

 

 

 

 

 

 

58

 

Table A4. (Cont’d)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

benzfialcohol) (2)

 

 

 

1-butanol (4) 23.01 14.59 6.70 16.34
2-methyl-1-propanol
(i sob UM alcohol) (1) 22.90 15.20 5.70 16.00
2—methyl-1-propanol
flsobutyl alcohol) (2) 23.00 13.12 7.92 17.16
2-methyI-1-pr0panol
(isobutyl alcohol) (3) 21.78 15.13 5.40 14.70
2—methyl-1-propanol
0 sob UM alcohol) (4) 22.39 14.12 6.66 15.93
2-butanol
(sec-Duty) alcohol) (1) 22.20 15.80 - -
2-butanol
(sec.-butyl alcohol) (2) 23.00 13.12 7.92 17.16
2-butanol

sec.-butyl alcohol) (3) 21.92 15.26 5.45 14.77
2—butanol

sec.-butyl alcohol) (4) 22.46 14.19 6.69 15.96
1-pentan0l (amyl alcohol) (1) 21.70 16.00 4.50 13.90
1-pentanol (amyl alcohol) (2) 22.69 13.64 7.38 16.56
1-pentanol (amyl alcohol) (3) 21 .34 15.79 4.62 13.59
1-pentanol (amyl alcohol) (4) 22.01 14.72 6.00 1 5.07
cyclohexanol (1) 224-233 17.40 4.10 1 3.50
cyclohexanol (2) 22.82 1 3.52 7.68 16.70
cyclohexanol (3) 22.89 17.58 4.80 1 3.86
cyclohexanol (4) 22.85 15.55 6.24 1 5.28

henol (1) 24.10 18.00 5.90 14.90
phenol (2) 25.45 14.12 11.48 17.79
phenol (3) 24.71 18.68 5.83 15.09
phenol (4) 25.08 16.40 8.66 16.44
amethy'phem' 22.70 181-194 5.10 12.90
(m-cresol) (1)
methy'phem' 24.28 14.38 10.41 16.55
(m-cresol) (2)
3-methylphenol
(m-cresol) (31 23.35 18.17 4.90 13.83
3-methylphenol

m—cresol) (4) 23.81 16.28 7.65 15.19
phenyl methanol
(be nzyl alcohol) (1) 23.80 18.40 6.30 13.70
pm" metham' 24.20 14.34 10.51 16.35

 

59

 

Table A4. (Cont’d)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(figggmflm 23.73 18.55 497 13.94
(mgfim'm 23.96 16.44 7.79 15.14
1983222332111) (1) 29.1 -33.4 16.90 1 1,10 25.00
233232;.) (2) 34.05 11.21 12.22 29.75
(2332:2313, (3) 34.18 17.15 12.63 26.73
232328531”) (3) 34.33 17.26 12.71 26.82
(gijfgfiggflggo (4) 34.19 15.21 12.52 27.77
1’2'p'°pa"edi°' 30.30 15.90 9.40 23.30

29.36 11.28 10.97 24.79

30.08 16.26 9.65 23,39

29.72 13.77 10.32 24.09
25mm?” (1) 29.00 16.60 10.00 21.50
kgfigflo (2) 27.12 11.68 10.11 22.29
($3,333,800 (3) 27.81 16.28 799 2112
(gmfiggffign (4) 27.45 13.98 900 2170
8.292333%?“ 33.8-43.2 17.30 12.10 29.30
Zififipgefim 33.59 10.24 12.40 29.50
ggfyfefgjgpgm 35.41 17.10 11.85 28.65
1é12y’2;':§,’)pg;efi°' 34.55 13.67 12.13 29.13
2812:5310 5:135:23) (1 ) 247° 1520 9.20 16.40
23533311252314?) (2) 26-37 13-53 9.26 20.66

 

60

 

Table A4. (Cont’d)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

2-methoxyethanol
mew cellosowe) (3) 24.86 16.12 8.13 17.09
2-methoxyethanol
methyl cellosolve) (4) 25.62 14.82 8.69 18.87
2—ethoxyehtan0l
eth 1| cell osolve) (1) 24.30 16.10 9.20 14.30
2-ethoxyehtanol
(ethyl cellosolve) (2) 24.71 13.09 9.24 18.81
2—ethoxyehtanol
(ethyl cellosolve) (3) 23.10 15.89 5.61 15.41
2—ethoxyehtanol
ethyl ceuosolve) (4) 23.90 14.49 7.92 17.11
2-but0xyethanol
(bum celloso've) (1) 21.00 15.90 5.40 12.10
2-butoxyethanol
(bum cellosolve) (2) 23.81 14.24 7.81 17.41
2-butoxyethanol
bum cellosolve)(3) 21.27 15.89 4.89 13.25
2-butoxyethanol
but” celloso've) (4) 22.54 15.07 6.35 15.33
hydroxy-4-methyl-2-
ntanone 18.8-20.8 15.7 8.20 10.90
diacetone alcohol) (1)
hydroxy-4—methyl-2—
entanone 22.78 12.38 10.04 16.28
diacetone alcohol) (2)
hydroxy-4-methyl-2-
entanone 21.98 15.83 7.41 13.33
diacetone alcohol) (3)
I4—hydroxy-4-rnethyl-2-
pentanone 22.38 14.10 8.73 14.80
(diacetone alcohgl) (4)
Acids
rmic acid (1) 24.9-25.0 143-153 11.90 16.50
(ohmic acid (2) 40.12 9.59 16.46 35.30
)onnic acid (3) 39.99 18.02 25.00 25.48
formic acid (4) 40.06 13.81 20.73 30.39
(acetic acid (1) 18.8-21 .4 145-166 8.00 13.50
[acetic acid (2) 24.04 13.39 10.09 17.23
Ecetic acid (3) 22.45 16.60 7.34 13.22
[acetic acid (4) 23.24 14.99 8.71 15.22

 

 

 

 

 

61

 

Table A4. (Cont’d)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

utyric acid (1) 188-231 149-163 4.10 10.60
butyric acid (2) 21 .38 14.60 8.35 13.20
butyric acid (3) 19.82 16.22 4.57 10.43
butyric acid 20.60 15.41 6.46 1 1.82
(acetic acid, anhydride (1) 21 .3-22.2 15.4-16.0 1 1.10 9.60
Ecetic acid, anhydride (2) 24.30 1 1 .88 13.61 16.26
@500 acid, anhydride (3) 22.02 16.11 12.30 8.61
[acetic acid, anhydride (4) 23.16 13.99 12.95 12.44
[Nitrogen compounds
“WWW“ 19.70 17.00 4.90 8.60

ropylamlne) (1)
1'am'"°p'.°pa"e 22.72 14.49 9.33 14.80

ropylamme) (2)
1-aminopropane

ropylamine)(3) 18.16 15.08 0.00 10.11
1-aminopropane

r 0 pyl ami n e) (4) 20.44 14.79 4.67 12.46
diethylamine (1) 16.30 14.90 2.30 6.10
diethylamine (2) 21.01 14.64 7.45 13.10
diethylamine (3) 15.99 14.89 2.03 5.47
diethylamine (4) 18.50 14.76 4.74 9.29
[aminobenzene (aniline) (1) 226-242 1 9.50 5.1 0 1 0.20
[amincbenzene (aniline) (2) 23.46 15.76 12.65 11.91
[ahiinobenzene (aniline) (3) 21.12 18.77 1.21 9.60

'nobenzene (aniline) (4) 22.29 17.26 6.93 10.76
2—aminoethanol

ethanolamine) (1) 31.70 17.10 15.60 21.30
2-aminoethanol
(ethanolamine) (2) 30.03 11.96 12.90 24.33
2-aminoethanol
ethanolamine) (3) 28.94 17.17 8.33 21.76
2-aminoethanol
ethanolamine) (4) 29.48 14.56 10.62 23.04
nitromethane (1) 25.1-26.0 158-164 18.80 5.10
nihomethane (2) 24.98 1 1.86 1 1.26 18.89
nitromethane (3) 26.65 17.03 19.81 5.27
nitromethane (4) 25.82 14.45 15.53 12.08
nitroethane (1) 22.70 16.0-166 15.60 4.50
nitroethane (2) 23.08 12.81 10.14 16.30

 

 

62

 

Table A4 (Cont’d)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

nitroethane (3) 22.89 16.68 14.99 4.58
nitroethane (4) 22.98 14.74 12.57 10.44
nitrobenzene (1) 205-219 176-199 12.30 4.10
nitrobenzene (2) 22.78 14.60 12.17 12.55
nitrobenzene (3) 21 .95 18.88 10.52 3.83
nitrobenzene (4) 22.36 16.74 1 1.35 8.19
(ethanenitn'le (acetonitrile) (1) 24.1-24.5 15.4-152 18.00 6.10
@anenitrile (acetonitrile) (2) 29.24 12.27 13.71 22.72
[gmanenitrile (acetonitrile) (3) 27.40 16.21 20.98 5.91
fitanenitrile (acetonitrile) (4) 28.32 14.24 17.35 14.81
methanamide

formamide) (1) 36.70 17.20 25.20 19.00
methanamide

formamide) (2) 33.28 10.22 17.37 26.48
methanamide

formamide) (3) 32.97 18.88 20.14 18.02
methanamide

fommide) (:1) 33.12 14.55 18.75 22.25
dimethylformamide (1) 24.90 17.40 13.70 1 1 .30

imethylfonnamide (2) 24.13 14.68 1 1.51 15.31
dimethylfonnamide (3) 21.33 14.30 12.17 10.1 1
dimethylformamide (4) 22.73 14.49 1 1.84 12.71
dimethylacetamide (1) 22.11228 16.80 1 1.50 10.20
dimethylacetamide (2) 21.24 16.78 1 .10 12.98
dimethylacetamide (3) 22.62 16.77 1 1.42 10.01
dimethylacetamide (4) 21.93 15.77 6.26 1 1.49
1,1,3,3-tetramethylurea (1) 21.70 16.80 8.20 11.10
1,1,3,3—tetramethylurea (2) 18.86 15.34 3.76 10.30
1,1,3,3-tetramethylurea (3) 25.80 19.10 1 1.42 13.05
1,1,3,3—tetramethylurea (4) 22.33 17.22 7.59 1 1.67
'Sulpher compounds
dimethyl sulphide (1) 18.40 17.50 - -
dimethyl sulphide (2) 21.47 13.95 9.72 13.10
dimethyl sulphide (3) 17.43 17.43 0.00 0.00
dimethyl sulphide (4) 19.45 15.70 4.86 6.55
diethyl sulphide (1) 17.30 150169 3.10 2.10
diethyl sulphide (2) 20.07 15.02 8.24 10.44
diethyl sulphide (3) 16.89 16.89 0.00 0.00

 

 

 

 

 

 

63

 

Table A4. (Cont’d)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

iethyl sulphide (4) 18.48 15.96 4.12 5.22

ater (1) 47.9-48.1 123-14.3 31.30 34.20
(Polymer
Polyethylene (2) 18.01 18.01 0.00 0.00
Polyethylene (3) 17.74 17.74 0.00 0.00
Pclyehtylene (4) 17.88 17.88 0.00 0.00
Polypropylene (2) 16.69 16.69 0.00 0.00
Polypropylene (3) 1 5. 55 1 5.55 0.00 0.00
Polypropylene (4) 16.12 16.12 0.00 0.00
Polystyrene (2) 20. 83 1 7.82 7.58 7.70
Polystyrene (3) 17.99 17.95 1.11 0.00
Polystyrene (4) 19.41 17.88 4. 34 3. 85
Polyvinyl Chloride (2) 20.33 15.44 11.26 5.95
Polyvinyl Chloride (3) 21.72 17.73 12.19 2.98
Polyvinyl Chloride (4) 21.03 15.58 1 1.72 4.96
Polyvinylidene Dichloride (2) 18.96 10.74 11.16 10.93
Polyvinylidene Dichloride (3) 23.35 18.82 13.31 3.70
Polyvinylidene Dichlon'de (4) 21.15 14.78 12.24 7.31
Polyvinyl Alcohol (2) 28.79 14.89 16.34 18.45
Polyvinyl Alcohol (3) 32.12 16.00 14.29 23.90
Polyvinyl Alcohol (4) 30.45 15.44 15.31 21 .18
Ej'yefl'y'em Temphfl‘a‘ate 24.50 15.62 13.87 12.81
gj'yethy'ene Temphtha‘ate 21.34 17.99 6.95 9.13
afiemy'm Temphfl‘a'a‘e 22.92 16.80 10.42 10.97
Nylon 6(2) 22.10 15.70 12.31 9.51
Nylon 5(3) 20.11 17.24 7.64 6.99
Nylon 6(4) 21.10 16.47 9.98 8.25

 

(1) Van Krevelen, 1990
(2) Hoy method

(3) Hoftyzer and Van Krevelen method

(4) Average values

64

 

APPENDIX 8

STANDARD CALIBRATION CURVE FOR THERMAL DESORPTION

Table 8.1. Calibration data for ethyl acetate in acetonitrile with 1 pt) injection
volume by TD-GC

 

 

 

 

 

 

 

 

 

 

   
 

 

 

Solution concentration Total Quantity Area Response
(cm) (9) (AU)
0 0 0

10 9.02E-09 114351
20 1.80E-08 257164
40 3.61E-08 558258
60 5.41E-08 ’ 762270
9.E+05 _
5 8.E+05 7
s. 7.E+05 -
3 6.E+05 7
E 5.E+05 1
g 4.E+05 -
I: 3.E+05 y=1E+13x-3618 .6
§ 1:3: R2=0.9995
' Calibration Factor = 1.00E-13
O-Em 1 l 1
0.E+00 2.E-08 4.E-08 6.E-08
Quantity (9)

Figure 8.1. Standard calibration curve of ethyl acetate in acetonitrile by TD-GC

65

 

Table 8.2. Calibration data for limonene in acetonitrile with 1 pl injection volume

 

 

 

 

 

 

 

 

 

 

 
   

 

 

by TD-GC
Solution concentration Total Quantity Area Response
(ppm) (9) (AU)
0 0 0
6 5.04E-09 194602
10 8.40E-09 296995
20 1.68E-08 514685
40 3.36E-08 971624
1.E+06 _
S .
S.- 1.E+06
E 8.E+05 —
§. 6.E+05 .
05° 4.E+05 - Y = 3E+13x + 35541
N
g 1305 , R2=0.9958
Calibration Factor = 3.33 E-14
O-Em ‘x l I l I
0.E+00 1.E-08 2.E-08 3.E-08 4.E-08

Quantity (9)

Figure 8.2. Standard calibration curve of limonene in acetonitrile by TD-GC

 

Table B.3. Calibration data for methyl ethyl ketone in xylene with 1 ul injection

volume by TD-GC

 

 

 

 

 

 

 

 

 

 

 

  
   

 

Solution concentration Total Quantity Area Response
(ppm) (9) (AU)
0 0 0

10 8.03E-09 211129
20 1.616-08 309065
40 3.21E-08 477840
100 8.03E-08 1180606
1.E+06 -

‘7 .E+ —

g 1 06

a 1.E+06 ‘

5 8.E+05 -

a

3 6.E+05 7 E

I; 4.E+05 q y- 1 2+13x+51532

R =0.9921
.E+ ~

2 2 05 Calibration Factor= 1.00E-13

O-E+m * l I I )

0.E+00 2.E-08 4.E-08 6.E-08 8.E-08 1.E-07

Quantity (9)

Figure B.3. Standard calibration curve of methyl ethyl ketone in xylene by TD-GC

67

 

Table 8.4. Calibration data for toluene in acetonitrile with 1 pl injection volume by

 

 

 

 

 

 

 

 

 

 

    
 
  

 

 

TD-GC
Solution concentration Total Quantity Area Response
(ppm) (9) (AU)
0 0 0
10 8.70E-09 280378
20 1.74E-08 548962
40 3.48E-08 910359
60 5.22E-08 1353807
2.E+06 7
S 1.E+06 -
<
i; 1.E+06 7
2 1.E+06 7
g. 8.E+05 —
g 6.E+05 7 =BE+13x+47209
g 4.E+05 7 R2=0.9941
3 NEWS Calibration Factor=3.33E-14
0.E+00 r 1 a
0.E+00 2.E-08 4.E-08 6.E-08
Quantity (9)

Figure 8.4. Standard calibration curve of toluene in acetonitrile by TD-GC

68

 

APPENDIX C

STANDARD CALIBRATION CURVE FOR SOLID PHASE MICROEXTRACTION

Table C. 1. Calibration data for ethyl acetate in water by SPME-GC

 

 

 

 

 

 

Total Quantity Area Response
(9) (AU)
0 0
9.02E-09 253222
1 .80E-08 384728
3.61E-08 580711
5.41E-08 774359

 

 

 

 

9-E'1'05 1
8.E+05 .
7.E+05
6.E+05
5.E+05
4.E+05 7
3.E+05 '

  
   

y = 1E+13X + 83710
2.E+05 i R2 = 0.9598
1.E+05 . Calibration Factor = 1E-13
0.E+00 X ' -
O.E+00 1.E-08 2.E-08 3.E-08 4.E-08 5.E-08 6.E-08
Quantity (9)

Area Response (AU)

Figure C. 1. Standard calibration curve of ethyl acetate in water by SPME-GC

69

Table C.2. Calibration data for limonene in water by SPME-GC

 

 

 

 

 

 

 

Total Quantity Area Response
(9) (AU)

0 0
3.11E-09 172709
6.22E-09 286079
1.24E-08 638591
1.40E-08 715777

 

 

 

   
 

 

 

8.E+05 -

:2; 7.E+05 .

: 6.E+05 ~

2 5.E+05 ~

§ 4.E+05 -

g 3.E+05 y=5E+13x-2566.6

8 15*“5 R2=0.9969

a 1.E+05 Calibration Factor=2E-14
0.E+00 . . .

0.E+00 5.509 1.E-08 2.E-08
Quantity (9)

Figure C.2. Standard calibration curve of limonene in water by SPME-GC

70

Table 0.3. Calibration data for methyl ethyl ketone in water by SPME-GC

 

 

 

 

 

 

 

Total Quantity Area Response
(9) (AU)

0 0
8.03E-06 35024
1.61E-05 138107
3.21E-05 264783
8.03E-05 670907

 

 

 

J

8.905
7.905
v 6.E+05
5.905
4.805 7
3.E+05 7
2.E+05 1

AU)

1

Area Response

 

1.E+05 1
0.E+00

    
   

Y = 8E+12x - 10141

R2 = 0.9974
Calibration factor = 1.25 E-13

 

 

I I T I

0.E+00 2.E-08 4.E-08 6.E-08 8.E-08 1.E-07

Quantity (9)

Figure 8.3. Standard calibration curve of methyl ethyl ketone in water by

SPME-GC

71

Table 0.4. Calibration data for toluene in water by SPME-G0

 

 

 

 

 

 

Total Quantity Area Response
(9) (AU)

0 0
1.91E-06 909858
3.83E-06 1829625
7.66E-06 3441474
9.57E-06 4478939

 

 

 

 

5.5106 7
5.E+06 7
4.E+06 7
4.5106 7
3.5106 7
3.5106 7
2.E+06 7
2.E+06 7
1.E+06 7

  
 

y = SE+14X 1' 18591

R2 = 0.9988
5.51705 7 Calibration Factor = 2E-15
051-00 1 l '

0.E+00 5.E-09 1.E-08 2.E-08
Quantity (9)

Area Response (AU)

 

 

Table 04. Standard calibration curve of toluene in water by SPME-GC

72

APPENDIX D

CALCULATION FOR THE PARTITION COEFFICIENT BY TSITD—GC METHOD

Concentration of sorbate in polymer [ij was calculated by the following
equaflon;

ma

[CD] = mp

Where m. is mass of sorbate in polymer and mp is the mass of polymer disks

respectively.

73

APPENDIX E

CALCULATION FOR THE PARTITION COEFFICIENT BY TSITD-GC METHOD

Concentration of sorbate in polymer [ij was calculated by the following

 

equafion;
(Ca,i 7 Ca,f)ma
[Cc] =
"'0
Where C.) is initial concentration of sorbate in the aqueous phase

0.1 is final concentration of sorbate in the aqueous phase
m. is mass of water contained in the vial

mp is mass of the polymer disks

74

APPENDIX F

STRUCTURE AND DETAILS OF SORBATES AND POLYMER

Table F. Structure and details of sorbates and polymer

 

 

 

 

 

 

 

Structure Molecular weight Density (glcm3)
LDPE R-CH2-CH2-R 28.1 0.923
leonene CH3 136.24 0.840
I \
CH3-C=CH2 H
Ethyl acetate CH3000H20H3 88.10 0.901
(I
0
Methyl ethyl ketone CH3CCH20H3 72.10 0.805
ll
0
Toluene 92.13 0.867

 

©—CH3

 

 

 

75

 

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76

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78

   

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