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LIBRARY
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University

 

 

 

 

This is to certify that the

thesis entitled

Evaluation of Seven Different Lamination Structures Based
on the Mechanical and Physical Properties

presented by

Andres A. Soto-Jimenez

has been accepted towards fulfillment
of the requirements for

_Ma.ster__degree in Jackaging;

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0-7639 MS U is an Affirmative Action/Equal Opportunity Institution

 

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TO AVOID FINES return on or before date due.
MAY BE RECALLED with earlier due date if requested.

 

DATE DUE

DATE DUE

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EVALUATION OF SEVEN DIFFERENT LAMINATION STRUCTURES BASED
ON THE MECHANICAL AND PHYSICAL PROPERTIES

By:

Andres A Soto-Jimenez

A THESIS

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

MASTER OF SCIENCE

School of Packaging

1998

ABSTRACT

EVALUATION OF SEVEN DIFFERENT LAMINATION STRUCTURES BASED
ON THE MECHANICAL AND PHYSICAL PROPERTIES

By

Andres A. Soto-Jimenez

This research will provide information and guidance on how to evaluate
flexible packaging lamination structures. The laminations studied were: three
different kinds of Dryflex material, three different kinds of Nylon material and one
kind of Tyvek® material. A detailed explanation of the manufacturing process for
each of them is included. This discussion is focused towards performance
testing.

The tests performed were classified in eight different categories. Each test
quantitatively compares the lamination structures on a variety of factors directly
related to performance in the following applications: Capping, Cost, Dart Drop,
Foil Delamination, Heat Seal, Performance on Pallets, WVTR and Sliding,
Folding and Label Adhesion. Each test provides general information, the test
description and test results. The testing was done according to ASTM standards
or to in-house testing methods. A detailed ranking system was used for each
test, to categorize the performance, with the intention of identifying the best

structure or the best performance.

The results show better performance from the Dryflex-B and Dryflex-C
structures, compared to the nylons and Tyvek®. Nylon laminations are suitable
for corrugated packages, but do not have the strength needed for other
applications. The lamination with the overall best performance was the Dryflex-
C. The main reasons for this result were: its manageability (Sliding, Folding and
Label Adhesion), the Foil Delamination test, and the WVTR test. In all these
tests the lamination reached the top score.

This study also demonstrate how the mechanical properties of a
lamination structure can be improved by adding a LLDPE layer. It is appropriate
to mention that a layer of LLDPE adds to the structure desirable properties
against puncture, in this study represented by the dart drop test. All the samples
that contained the LLDPE layer performed six and above in the ranking scale,
while those which did not have it performed lower, with the exception of Nylon-A,
which has a thicker nylon layer.

This study provide guide lines to objectively evaluate and select different
numbers of alternatives based on the lamination performance. The same
concepts can be adapted to other applications, in which it will be necessary to

select one alternative among others.

FOR:

To my friends, Carla, Sunetra, Henrique and T atsutya, who supported me during
two beautiful years in East Lansing and to Jefl who constantly reminded me to finish.

T 0 my family, Naydita, Mami and Papi, because you always motivate me to reach
my dreams.

To my wife Madelene and our future child, because you have believed on me and
you are the shining star of my life.

ACKNOWLEDGEMENTS

I would like to thank the following
organizations, who sponsor and enable me to realize
my career at Michigan State.

a EOP / urban affairs organization
a Puerto Rico Economic Development

May God please bless Dr. James E. Jay and his
office of Diversity and Pluralism, for supporting me and
providing me the opportunity to work as a research
assistant in the Packaging School, although, I could
not speak fluent English upon my arrival to NA.

Special Thanks to my Major Professor Dr.
Susan E. M. Selke Ph.D., for her guidance, support,
leadership and example.

iv

TABLE OF CONTENTS

LIST OF TABLES .............................................................................. vi
LIST OF FIGURES ............................................................................ vii
1.0 INTRODUCTION .................................................................................. 1
1.1 Package Description .................................................................. 3
2.0 THE FILM LAMINATION PROCESS ................................................. 7
2.1 Adhesion Lamination ................................................................. 7
2.2 Extrusion Lamination .................................................................. 11
2.3 Adhesive and Cohesive Failure ................................................. 12
2.4 Description of the Laminations ................................................... 16
2.5 Composition of the Laminations .................................................. 17
3.0 PERFORMANCE TESTING AND RESULTS .................................... 23
3.1 Capping Test ............................................................................... 24
3.2 Cost Analysis ............................................................................... 27
3.3 Dart Drop (Puncture Resistance) Test ......................................... 29
3.4 Foil Delamination Test ................................................................. 31
3.5 Heat Seal Test ............................................................................. 39
3.3 Performance on Pallets Test ....................................................... 44
3.7 Sliding, Folding 8. Label Adhesion Test ....................................... 50
3.8 Water Vapor Transmission Rate Test ......................................... 53
3.9 Summary of Results ..................................................................... 56
4.0 CONCLUSIONS ................................................................................ 58
APPENDIX ........................................................................................ 62
REFERENCES .................................................................................. 98

LIST OF TABLES

Table 1: The Dryflex-A Structure ................................................................ 18
Table 2: The Dryflex-B Structure ...................................................... 19
Table 3: The Dryflex-C Stmcture ...................................................... 20
Table 4: The Nylon-A Structure ........................................................ 20
Table 5: The Nylon-B Structure ........................................................ 21
Table 6: The Nylon-C Structure ........................................................ 22
Table 7: The Tyvek® Structure ......................................................... 22
Table 8: Results of the Capping Operation Test ............................... 26
Table 9: Lamination Cost per Roll ..................................................... 28
Table 10: Results of the Dart Drop Test ........................................... 30
Table 11: Results of the Foil Delamination Test ............................... 38
Table 12: Results of the Heat Seal Test ........................................... 43
Table 13: Packaging Elements for Wood and Plastic Pallets ........... 46
Table 14: Results of the Performance on Pallets Test ...................... 49

Table 15: Results of the Sliding, Folding and Label Adhesion Tests 52

Table 16: Results of the WVTR Test ................................................ 55
Table 17: Summary of the Test Results ............................................ 57
Table 18: Summary of the Rating Results ........................................ 57

vi

LIST OF FIGURES

Figure 1: Package Description ................................................................... 4

Figure 2: Wet Bonding Adhesion ...................................................... 9

Figure 3: Dry Bonding Adhesion ....................................................... 10
Figure 4: Adhesive Extrusion Process .............................................. 12
Figure 5: An Adhesive Failure .......................................................... 14
Figure 6: A Cohesive Failure ............................................................ 15
Figure 7:The Capping Operation ...................................................... 25
Figure 8: Lamination Sample of Ten Square Inches ......................... 34
Figure 9: Stretched Lamination Sample ............................................ 34
Figure 10: Cut to the Lamination ....................................................... 35
Figure 11: Foil Delamination ............................................................. 37
Figure 12: Test Panel ........................................................................ 41
Figure 13: Test Specimen ................................................................. 42
Figure 14: Extended Core ................................................................. 45
Figure 15: Loaded Forklift ................................................................. 47

vii

1.0 INTRODUCTION

Survival, in today's world marketplace, is strongly influenced by a
company's ability to maintain a competitive edge. Companies that are able to
maximize product performance and quality, while minimizing cost, will remain
profitable and will remain in business. These are the companies using the right
tools for improvements. One of the most valuable tools a company can employ
to maintain and to improve its competitive edge is packaging. This is
accomplished by optimizing and standardizing the type of package used as well
as preserving the value of the product at the lowest cost.

This study has been made on the primary package of the polyvinyl butyral
roll. Tough, resilient polyvinyl butyral (PVB) is used as a plastic interlayer in
manufacturing laminated glass for use in both commercial and residential
applications. The performance benefits of laminated glass include improved
safety, security, sound control, solar control, UV screening, structural strength,
hurricane resistance, earthquake performance, and wide color range.

Laminated glass is the same type of glass used in car Windshields, in the
Louvre Pyramid in Paris France, and in aircraft windows. it consists of two
pieces of glass bonded together permanently through heat and pressure. Once
bonded together, this 'sandwich' behaves as a single piece. The interlayer is
invisible when viewed through the glass, and with glass on either side, the

finished product is indistinguishable from plain glass when installed. Most often,

laminated glass is produced using annealed glass, but heat strengthened or
tempered glass can be used when special performance needs are present. if
the glass is broken, the glass fragments adhere to the plastic interlayer rather
than falling free and potentially causing injury. Laminated annealed glass can
be cut or drilled (Monsanto, 1997).

The three main raw materials used to make polyvinyl butyral are: resin,
plasticizer and stabilizer. The ingredients are mixed together and then fed into
the extrusion process where the mix is melted and is flawed to a die roll to form
the polyvinyl butyral sheet. The sheet is conveyed down the line over hot rolls to
eliminate any stresses in the sheet, then into a hot tub to reach the desired
moisture content. Next, the sheet goes into a cold bath to stiffen it. Following
the cold bath, the sheet runs through air knives for drying. The sheet is checked
online for thickness profiles. The edges of the sheet are trimmed for the desired
winding width. Later, the sheet runs though an “on line” laser that detects any
defects. The sheet is finally wound into rolls on the winder. The rolls off the
winder are identified and packed in laminated bags. This constitutes the
primary package of the polyvinyl butyral roll.

The bags are made of a lamination, or combination of different substrates
added together. ln-house, the lamination is heat sealed, cut to size and
converted into a bag. The bag will protect the roll, not only from the migration of
moisture, but also from damage during handling and transportation.

in the lamination, each layer has a specific function. For example, the

outer layer is for the strength, puncture resistance, and most of the mechanical

properties of the lamination. Two tie layers will work as adhesives to add the foil
to the lamination. The aluminum foil layer will provide the barrier properties, the
protection against the migration of moisture and oxygen into the roll. The
sealant layer will manage the heat seal performance. Using an adhesion or an
extrusion manufacturing process, all these layers are pieced together to form the
lamination structure. Different arrangements of the layers, as well as different
kind of layers, will result in different physical and mechanical properties.

One of the objectives of this study is to develop an effective replacement
alternative for the current lamination outer layer (T yvek®). The criteria for a
successful replacement were based on the performance of the mechanical
properties, physical properties and cost of the lamination. During a period of
eight months, several alternatives were considered. The following information

contains the criteria for the selection of the replacement lamination structure for

the polyvinyl butyral bag.

1.1 Package Description

The polyvinyl butyral roll is wound on a plastic core or tube. Each roll
can weight more than 1000 pounds and overall measurements vary from ~ 30"
wide up to 60" high. in the winder, it is covered with a polyethylene (PE) wrap to
prevent contamination from flying or loose particles. At the same level of
packaging, a bag (made of the lamination) is placed around the roll. One of the
bag’s end has been heat sealed; the other one is open for transportation and roll

handling. Once the roll reaches the transportation pallet, it is conveyed to the

capping station. Here the surplus bag length is inserted into the core and the
bag is sealed with a core plug or cap. Figure 1 contains a description of the

packaging elements.

Figure 1: Package Description

Platte top tray
intimted bag

 

- Poiyvinyl tutyrd rdl
-+ coveredwithPqu>

 

 

    

 

 

 

 

 

 

In summary, the primary elements of the package are:
- Plastic core or hollow tube, to wind on
- PE wrap, to prevent dust contamination

- Bag, principal element for protection

-Ckxerflug,u:sealflnabag

There are two different kinds of secondary packages for the polyvinyl
butyral roll: it can be packaged in a plastic returnable package or in a corrugated
non-renunabhipackage.Thnlnonqehnnabkrpackageislumnposedrmialuood
pallet, a corrugated bottom tray, a corrugated pad, a conugated side wall, and a
corrugated top tray. it is banded with a polyethylene terephthalate (PET) band
and then identified with a label. The returnable package is composed of a
bottom plastic pallet and a plastic top tray. It is banded together with a PET
band and then identified with a label. The corrugated non-retumable package
contains more components. All these packaging items can be reusable and
recyclable, but the corrugated package is environmentally ineffective compared
with the returnable package. The returnable package requires a bigger initial
cost investment, but with a reasonable number of turns, it not only reaches the
break even point, but also gives an excellent return on the initial investment.

The industry trend is to implement the use of returnable packages to
contribute not only to the environment, but also to the company source reduction
policies. At this time, the primary package of the polyvinyl butyral roll becomes
critically important. All the protection against transportation damage is provided
by the laminated bag. This study will evaluate the performance of seven
different lamination structures, with the aim of obtaining one, with reliable
mechanical and physical properties to provide the desired protection. For
identification purposes, all the bag laminations will be named by their outer

layer

The alternatives for consideration are:

* Dryflex-A, lamination with an outer layer of 3.0 mil ValeronO

* Dryflex-B, lamination with an outer layer of 2.5 mil Valeron®

* Dryflex-C, lamination with an outer layer of 2.5 mil Valeron® and
low density polyethylene (LDPE) as the sealant layer

" Nylon-A, lamination with an outer layer of 67 gauge Nylon and a
Saran® coating

" Nylon-B, lamination with an outer layer of 60 gauge Nylon and
ethylene-vinyl acetate (EVA) as the sealant layer

* Nylon-C, lamination with an outer layer of 60 gauge Nylon and
linear low density polyethylene (LLDPE) as the sealant layer

* Tyvek®, lamination with an outer layer of 2.0 mil Tyvek®

(widely used in North America)

The layer by layer composition, as well as the manufacturing methods
used to manufacture each of the above lamination structures, will be covered in

Section 2.

2.0 The Film Lamination Process

Lamination of two or more films to each other can often achieve a more
desirable balance of properties than could ever have been obtained by
modifying one of the structures. One layer may provide mechanical properties
while another provides controlled permeability, heat sealability, printability,
fogging resistance, chemical resistance or other important qualities.
Occasionally laminates may involve three or more layers of different materials.
Thus, a manufacturer, by the installation of one piece of equipment for
accomplishing such combinations, is immediately able to make a very broad
range of possible packaging structures. The key step in laminating is the
creation of a strong adhesive bond between the films (Osborn, 1992). Adhesive
and extrusion lamination manufacturing processes were used to obtain the

desired testing samples for the study.

2.1 Adhesive Lamination Process

Adhesive lamination is adaptable to short as well as long runs and it is
well-suited to the one-step production of laminates when more than two
components are present. The adhesive lamination manufacturing process was
used during the manufacture of the lamination Nylon-C, when the aluminum foil
was added to the Nylon outer layer. Another example of the adhesive lamination

manufacturing process was when the Saran®, or polyvinylidene chloride

(PVDC), was added to the Nylon-A structure. Adhesive laminating processes
can be divided into two major categories, namely, wet bonding and dry bonding.
The major difference between wet and dry adhesive bonding in the
manufacturing process is the location of the drying oven. in wet bonding, the
drying oven is placed after both substrates are joined, while in dry adhesive
bonding the drying oven is placed after the adhesive application, before the
addition of the second substrate. In terms of performance, dry bonding is more

suitable for film laminations than wet bonding.

2.1.1 Wet Bonding

Wet bonding (Figure 2) uses solvent or aqueous-based adhesives, and it
can only be used when one or more of the webs is permeable to the water or
other solvent used in the adhesive formulation. Adhesives can be either
thermoplastic or therrnoset. Thermoplastic adhesives, such as piasticized vinyl
acetate/vinyl chloride copolymers, lack heat resistance so their bonding
capability is restricted in their heat sealing range. Therrnoset adhesives
undergo crosslinking after the lamination has been made, leading to greater heat
resistance. Emulsions of acrylics are also used, as is PVDC when gas barrier is

needed, but they provide only moderate levels of adhesion.

Figure 2: Wet Bonding Adhesion

Rubber roll Nip Roll

   

 

 

Substrate # 1

 

 

 

 

Grsvure roll

 

 

MIMI” ‘59 Substrate”

Wet bonding is not usually successful with plastic films even when
laminating them to paper (Briston, 1989). However, wet bonding using organic
solvent-based adhesives has been carried out in some instances, and even
aqueous-based adhesive lamination can be carried out for films such as
cellulose acetate when bonded to paper. The cellulose acetate is fairly
permeable to water vapor and so aids drying out of the water after laminating. In
any case, the finished laminate must be run through a drying oven to speed up
the drying process. The gravure roll is the roll in contact with the adhesive and it
is also the roll which applies the adhesive to the substrate. The rubber roll
receives all the pressure made by the gravure roll and it secures the amount of
adhesive placed on the substrate. The metal and the nip roll are the ones which

bond the second substrate to the first substrate by surface contact pressure.

2.1.2 Dry Bonding

The dry bonding process incorporates either the use of an aqueous or
solvent-based adhesive film that is dried prior to laminating, or a hot melt
adhesive, based on wax or on one of a range of polymers. In the first case, the
aqueous or solvent-based laminating adhesive is applied in precise amounts to
one web by means of direct gravure or reverse kiss coaters. The coated web is
then passed through an oven, to remove all water or solvent, and later it is
combined with the other ply in a pressure nip, which sometimes may be heated.

The setup is shown schematically in Figure 3.
Figure 3: Dry Bonding Adhesion

Rubber rol

NIpRoI
\w

 

 

 

 

 

 

Subdmto‘Z

1O

Factors affecting the success of this type of laminating process when
used for plastic films include tension control, accurate adhesive application and
accurate control of drying. Film tension should normally be kept to a minimum
and will depend on the distance the film has to be pulled through the laminating
equipment and on the sharpness of any change in direction as it passes over the
various rolls. Smooth and accurate application of the adhesive is extremely

important, and failure in this respect will probably lead to delamination.

2.2 Extrusion Lamination Process

In the extmsion lamination manufacturing process, an extruded adhesive
is used, such as polyethylene or ethylene copolymer. High adhesive application
temperatures are often employed to oxidize the melt and improve adhesion.
Waxes are used to modify melt properties. A lamination process using extruded
adhesive is shown in Figure 4. A complication in laminating is that two different
films or a plastic film and a non-plastic substrate must be simultaneously brought
together to be combined. Good mechanical and electrical precision is
necessary to keep film speed coordinated. Control of tension is critical to avoid
wrinkles.

When plastic films are combined with non-plastic substrates, the
appropriate techniques for handling the substrates must be employed. For
instance, thin aluminum foil, such as the one used for this study which has a
thickness of 0.00035 inches, has lack of ductility and low tear strength. it

requires extreme care of tension control and avoidance of nicked foil edges.

11

This adhesion manufacturing process was used to make all the Dryflex and the

Tyvek® laminations used in the study.

Figure 4: Adhesive Extrusion Process

Film die
Substrate # 2

 

To wind up
‘—-—-—

   

 

 

Melt stream
+——
' ) Q g
/ /NIP I'OII
Quench roll

N‘ '9‘1
- AA '_

2.3 Adhesive and Cohesive Failure

A wide variety of polymers are applied as a thin layer between two solid
substrates, and employed primarily to bond and hold these two substrates close
to each other. To be a good adhesive, a polymer must first have sufficient
fluidity, polarity, and reactivity to flow and wet the surface of both substrates; and
when the bond has been completely formed, the polymer must have in addition
sufficient cohesive strength to hold itself as well as the substrates together

(Deanin, 1972).

12

There are many factors to consider when evaluating the performance of
seal strength in multi-layer laminated structures. One very important factor is
the tenacity with which layers are held together by the tie layer adhesive.
Structures having insufficient bond strength, for a given application, run the risk
of field failure due to delamination. Once delamination occurs, the aesthetics
and functionality of the package is destroyed. As a consequence, measurement
of bond strength is one of the standard qualification tests of a multi-layer
structure. The peel-type failure is probably the most common mode of field
failure. For this reason, peel strength tests have been adopted as the
predominant test for indication of bond strength. Within the numerous
variations of peel test available, the T-peel test (ASTM 01876-95), is the most
widely used and it was selected to perform the heat seal peel test in this study.
There are two types of failures when performing a T-peel test: adhesive failure
(Figure 5) and cohesive failure (Figure 6).

An adhesive failure occurs between two phases. This failure occurs when
there is delamination at the adhesive and the adherend is exposed. Suppose
we are situated between an atom of the adherend and an atom of the adhesive,
in other words we will assume failure started “in adhesion”. To continue 'in
adhesion”, the crack must grow between the next pair of adherend and adhesive
atoms. The alternatives are: to advance between two atoms of adherend or
between two atoms of adhesive. if each atom occupies an approximately
cubical space, it is easy to see that there are three paths between adherend and

adherend and three paths between adhesive and adhesive for each path

13

between adherend and adhesive. If the failure propagates into the adherend,
the failure will be considered an adhesive failure. if the failure propagates only
through the adhesive, it will be a cohesive failure (Bikerrnan, 1962).

This type of failure (adhesive) will expose to the peel surface the other
components of the multi-layer structure. An example of this failure is when the
seam was tested in section 3.5, and alter the test, aluminum foil particles flew

out of the lamination.

Figure 5: An Adhesive Failure

Adherend

 

Adhesive

 

 

 

 

 

Adherend

14

A cohesive failure occurs within a phase or within the adhesive. This type
of failure is desirable when the laminations studied are opened during the peel
test. At this point, the failure is desirable (for the studied laminations or
package) in the heat seal layer, i.e. LDPE, LLDPE or EVA This failure will
assure the other components of the lamination remain in place, without being
exposed to the surface. In general, for this experiment, is desirable to obtain

cohesive failure within the adhesive layer.

Figure 6: A Cohesive Failure

Adherend 5

4 11“ Adhesive

 

 

 

 

 

 

 

Adherend

15

2.4 Description of The Film Laminations

Seven alternative lamination structures were studied. Each of them
differs from the others in either thickness, layer composition or material used.
Even though they differ in composition, all of them follow a generally similar

arrangement, i.e.:

- An outer layer, which provides most of the mechanical properties; this
layer is always placed in the outside of the structure.

- A tie layer, which is used to adhere the barrier layer (aluminum foil) to
the lamination; the tie layer always follows the outer layer in the structure.

- A barrier layer, which will provide the oxygen and moisture protection; it
is always located in the middle of the structure.

- A tie layer, to add a cover to the barrier layer and prepare the structure
for the addition of the sealant layer.

- A sealant layer, which provides all the heat seal properties of the

structure.

In addition to the general arrangement of the layers in the structure, the
laminations also have in common the barrier layer composition and thickness.
All of them have aluminum foil film with a thickness of 0.00035 inches. The
outer layer, as well as the sealant layer and the tie layer, vary from lamination to
lamination. In fact, this variation gives the specific mechanical and physical

properties of each of them.

16

One of the most critical properties of the film is the protection against
moisture migration. Polyvinyl butyral is a hygroscopic product. Migration of
moisture through the film will result in shelf life reduction and eventually product
damage. This requires utilization of aluminum foil in the lamination. Keeping
the generation of pin holes in the aluminum to a minimum is important as well.
The generation of pin holes in the structure will be covered in more detail in the

water vapor transmission rate (WVTR) testing (Section 3.8).

2.5 Composition of the Laminations

This section will describe the layer by layer composition and the thickness
of each of the lamination structures studied. As described in section 1.1, the
lamination structures for evaluation are:

- three different arrangements using Valeron® as the outer layer,
structures Dryflex-A, Dryflex-B and Dryflex-C.

- three different arrangements using a polyamide as the outer layer,
structures Nylon-A, Nylon-B and Nylon-C.

- one arrangement using Tyvek® as the outer layer, Tyvek® structure.

Valeron® is manufactured by Valeron Plastics, Inc. in Houston, Texas,
part of the Van Leer international organization. They produce a unique HDPE
film lamination for commercial use. One of the applications of Valeron® is to
make heavy duty shipping sacks (Bruins, 1974). Valeron® is cross laminated by

adding two film layers of HDPE in a 45° degree orientation. The result is one

17

new film layer with superior tear strength in the machine (MD) and cross
machine direction (XMD).

Nylon films are a commodity item, and they can be obtained easily from a
variety of suppliers. Tyvek®, spunbonded olefin, is a trade mark of DuPont. It is
stronger than paper and more versatile than fabric. Made from HOPE fibers, this
spunbonded olefin is an extremely versatile material that combines some of the
properties of paper, film and cloth, (Dupont, 1997). its unique combination of
properties makes Tyvek® ideal for a broad range of applications. In the

following sections, the details of each lamination will be covered.

2.5.1 The Dryflex-A Structure

The Dryflex-A structure (Table 1), is composed of five layers. This
structure was developed, manufactured and experimentally tested with excellent
results. In fact, it was the strongest structure, but at the same time, it was

difficult to work with. The layer by layer composition is:

Table 1: The Dryflex-A Structure

 

 

Material Layer in the lamination Thickness
Valeron® outer 3.00 mil
LDPE tie 1.20 mil
Aluminum Foil barrier 0.35 mil
LDPE tie 0.80 mil
LLDPE sealant 1.25 mil
total thickness = 6.60 mil

 

18

 

 

2.5.2 The Dryflex-B Structure

The Dryflex-B structure (T able 2), is composed of five layers, the same as
Dryflex-A The major difference between them is the decrease in thickness of
the outer layer. This structure was developed, manufactured and experimentally

tested with excellent results. The layer by layer composition is:

Table 2: The Dryflex-B Structure

 

 

Material Layer in the lamination Thickness
Valeron® outer 2.50 mil
LDPE tie 1.20 mil
Aluminum Foil barrier 0.35 mil
LDPE tie 0.80 mil
LLDPE sealant 1.25 mil
total thickness = 6.10 mil

 

 

2.5.3 The Dryflex-C Structure

The Dryflex-C structure (Table 3), is composed of four layers. Differently
than the previous two structures, Dryflex-C uses the second tie layer of LDPE
simultaneously as a sealant layer. In order to make the seal reliable, additional
thickness was added to the layer. The outer layer is the same as Dryflex-B. This
structure was developed, manufactured and experimentally tested with excellent

results. The layer by layer composition is:

19

 

Table 3: The Dryflex-C Structure

 

 

Material Layer in the lamination Thickness
Valeron® outer 2.50 mil
LDPE tie 1.20 mil
Aluminum Foil barrier 0.35 mil
LDPE sealant 1.20 mil
total thickness = 5.25 mil

2.5.4 The Nylon-A Structure

 

 

The Nylon-A structure (Table 4), is composed of six layers. This

lamination contains the highest amount of Nylon of all structures tested and it is

the only one that contains a Saran® coating. The second tie layer is a co-

extrusion of ethylene—methacrylic acid copolymer (EMAA) and LDPE, to enhance

the lamination properties of the structure. The layer by layer composition is:

Table 4: The Nylon-A Structure

 

 

Material Layer in the lamination Thickness

Nylon outer 0.67 mil

Saran® coating 0.05 mil

LDPE tie 1.20 mil

Aluminum Foil barrier 0.35 mil
EMAAI LDPE tie 0.066 I 0.60 mil

EVA sealant 1.50 mil

total thickness = 4.43 mil

 

20

 

 

 

2.5.5 The Nylon-B Structure

The Nylon-B structure (T able 5), is composed of five layers, different from
Nylon-A It does not contain the Saran® layer, nor the EMAA co-extrusion for

the second tie layer. The layer by layer composition is:

Table 5: The Nylon-B Structure

 

 

Material Layer in the lamination Thickness
Nylon outer 0.60 mil
LDPE tie 1.20 mil

Aluminum Foil barrier 0.35 mil
LDPE tie 0.80 mil
EVA sealant 1.50 mil

total thickness = 4.45 mil

 

 

2.5.5 The Nylon-C Structure

The Nylon-C structure (T able 6), is composed of five layers, the same as
Nylon-B, but it was the thinnest structure. This structure does not contain
extruded LDPE, and for adhering the nylon to the foil, the dry bonding process
was used. The sealant layer is a blend of 90% LLDPE and 10% LDPE; this

layer provides excellent puncture properties. The layer by layer composition is:

21

 

Table 6: The Nylon-C Structure

 

 

Material Layer in the lamination Thickness
Nylon outer 0.60 mil
Adhesive tie 0.30 mil
Aluminum Foil barrier 0.35 mil
Adhesive tie 0.10 mil
LDPE:LLDPE sealant 2.90 mil
total thickness = 4.25 mil

2.5.7 The Tyvek® Structure

 

 

The Tyvek® structure (T able 7), is composed of five layers. This

structure is similar to the Dryflex structures in configuration, but it possesses

excellent tear and puncture properties.

The overall performance of this

lamination was excellent; the major disadvantage is the cost compared to the

other laminations. The Tyvek® lamination can be three times as expensive as

the Nylons and twice as expensive as the Dryflex.

composition is:

Table 7: The Tyvek® Structure

The layer by layer

 

 

Material Layer in the lamination Thickness
Tyvek® outer 2.00 mil
LDPE tie 1.20 mil
Aluminum Foil barrier 0.35 mil
LDPE tie 0.80 mil
EVA sealant 1.50 mil

 

22

 

 

 

3.0 Performance Testing and Results

This study is focused on the evaluation of the performance of the
mechanical and physical properties of the lamination structures described. in
order to adequately identify which lamination performs best and which performs
worst, they must be tested. The results of this testing will be objective criteria to
categorize the laminations.

This section contains the description of the testing performed on the
laminations, as well as the results of each test. A total of nine different tests and
a cost comparison were considered in this study. They were grouped in nine
sections:

3.1 Capping test

3.2 Cost analysis

3.3 Dart drop (puncture resistance) test

3.4 Foil delamination test

3.5 Heat seal test

3.6 Performance on pallets test

3.7 Sliding, folding and label adhesion test

3.8 Water vapor transmission rate test

3.9 Summary of the results

The testing covers all the operations to which the lamination or bag will be

subjected from the moment it is manufactured. Test are listed in alphabetical

23

order with descriptions and the results obtained. Some of the tests were
designed for in-house operation and they lack an ASTM standard. in such
cases, this study will provide all the details necessary for reproducibility. All test
samples were conditioned according to ASTM D 4332-89 (Standard Practice for
Conditioning Containers, Packages, or Packaging Components for testing).

in order to fairly compare the alternatives a ranking system was
developed. This ranking will be found in the results section, in the tables with
the summary for each test. The ranking was developed using the following
method:

- Use the highest result of each specific test as the top score.

- Divide the top score by eleven.

- The result is the increment unit for eleven intervals, from zero to ten

(0-10), to be used in each section.

A detailed description of the increment of the scale will be given in each section.

A summary of all the tests in a tabulated form is in Section 3.9.

3.1 Capping Test

The capping test is an in-house test that provides information about the
lamination's resistance to cuts during the capping operation. Earlier, in Section
1.1, the packaging elements were described, as well as the way the bag is
tucked or inserted into the core. Since the polyvinyl butyral roll is hygroscopic
and the bag is its moisture barrier, the seal must be as good a barrier as the bag

itself. Otherwise, moisture will migrate through the seal. The seal is provided

24

by a cap inserted into the core with an interference fit, providing the seal by the
pressure placed on the tucked bag against the core walls The right side of
Figure 7 shows an inserted cap. The capping operation (Figure 7) is performed
by inserting the core plug cap into the core using a hammer. The caps are made
of HDPE and they are inserted by pressure into the core, sealing the bag in
place. Sometimes while performing the capping operation, if the lamination is
weak, it can be cut by the pressure generated during the penetration. If the bag
is cut, the barrier properties will be lost, and with them the quality of the product.
For this reason, this test is important. It becomes even more important when the

roll is partially used and the capping operation is performed repetitively.

Figure 7: The Capping Operation

M - Cap providing the
seal by pressu
laminated bag
~Core PIE Cap

 

 

 

 

 

25

3.1.1 Capping Test Description

The method used to perform this test was based on the repetition of the
capping operation. The number of times in which a core plug cap was inserted
into the core without making a cut in the bag was taken as the result. This test
was performed on three samples for each lamination and the average

determined.

3.1.2 Capping Test Results

The data for the capping operation tests are listed in Appendix A in
Tables A1 to A7. The average number of times the capping operation can be
repetitively performed before a cut or a failure occurred in the lamination

structure is reported in Table 8.

Table 8: Results of the Capping Operation Test

 

Laminations Capping Results Ranking Results
Dryflex-A = 38.7 10
Dryflex-B = 29.3 8
Tyvek® = 17.7 4
Dryflex-C = 16.7 4
Nylon-C = 14.7 4
Nylon-A = 1 1.3 3
Nylon-B = 9.3 2

 

 

 

 

26

 

From the results, it can be concluded that the strongest lamination in terms of
cut resistance during the capping operation is Dryflex-A The structure most
susceptible to cutting was the Nylon-B structure. An interesting result from
evaluation of the nylon structures, was that better results were obtained by
having the sealant layer of LLDPE (Nylon-C) rather than by increased thickness
in the Nylon layer (Nylon-A). All the Dryflex structures performed better than the
nylons in this test. Also the Tyvek® stmcture performed acceptably.

In order to categorize the results, as described in Section 3.0, a ranking
or a scale was developed (Table 8: Ranking Results column). In this scale, a
grade of ten was given to the best performance and a grade of zero to an
unacceptable performance. The scale was developed by using equal
increments of 3.52 units, is. from 0 to 3.52 was rated as a '0', from 3.53 to 7.05
was rated as a '1' and so on. A ranking of 10 was given to Dryflex-A with an
average number of times that capping operation was performed before a cut of
38.67, while a ranking of 2 was given to Nylon-B with an average of 9.33 times

before a out.

3.2 Cost Analysis

Since the cost information on these lamination structures is classified as
confidential information, this study will present a comparison of the price on a
per roll basis (Table 9). In order to maintain confidentiality, the roll size and the
roll width will not be described. in general, the roll sizes are equal in terms of

length and width, making the same numbers of bag out of each roll.

27

Making a lamination structure is labor intensive, and it requires
technology and expertise to put all the layers together, making the final product

an expensive one.

Table 9: Lamination Cost per Roll

 

Laminations Cost per Roll (5) Ranking Results
Nylon-A = 307.38 6
Dryflex-C = 347.78 6
Dryflex-B = 368.54 5
Dryflex-A = 473.43 4
Nylon-C = 491.34 4
Nylon-B = 583.64 2
Tyvek® is = 779.07 0

 

 

 

 

In order to categorize the results, as described on Section 3.0, a ranking or a
scale was developed, (Table 9: Ranking Results column). in this scale, a grade
of ten was given to the best performance and a grade of zero to an unacceptable
performance. The scale was developed by using equal increments of 70.8
dollars, i.e. from 0 to 70.8 was rated as a '10", from 70.9 to 141.7 was rated as a
'9' and so on. Since no roll cost under seventy-one dollars, no ranking of 10
was given. A ranking of six was given to Nylon-A and Dryflex-C, while a ranking

of 0 was given to Tyvek® as the most expensive material.

28

 

One roll of Nylon-A, Dryflex-C or Dryflex-B, can be obtained for less than
half the price of the Tyvek® material. These prices are associated with minimum
order quantities and periodic orders.

3.3 Dart Drop (Puncture Resistance) Test

This test was performed according to ASTM standard D1709-85, Impact
Resistance of Polyethylene Film by the Free Falling Dart Method. One measure
of impact strength or puncture resistance is the force required to rupture a
plastic film. This test method covers the determination of the energy that causes
the different films to fall under specified conditions of impact of a free falling dart.
This energy is expressed in terms of the weight (mass) of the missile falling from

a specified height which would result in 50% failure of the specimens tested.

3.3.1 Dart Drop Description

The dart drop method used in this study was Method B, the standard
staircase technique. Using this technique, a uniform weight increment is
employed during the test and the missile weight is increased or decreased by
the uniform increment after test of each specimen, depending upon the result
(fail or not fail) observed for the specimen. The testing procedure used as well

as the apparatus is described in the ASTM standard.

29

The following summarizes some conditions of the experiment:

drop height = 60 inches
dart weight = 48.35 grams
rings = 15.25 grams

3.3.2 Dart Drop Test Results

The entire data for each drop test in this study on laminated film are listed
in Appendix B in Tables 81 to 87. These tables list the impact failure weight
(IFW), along with failures and non failures at each tested weight. A summary of

the data is presented in Table 10.

Table 10: Results of the Dart Drop Test

 

Laminations Dart Drop Result Ranking Results
IFW for Dryflex-A = 601.44 grams 10
iFW for Dryflex-B = 521.76 grams 8
IFW for Nylon-A = 413.93 grams 6
IFW for Nylon-C = 395.63 grams 6
IFW for Nylon-B = 299.53 grams 4
iFW for Tyvek® = 290.40 grams 4
IFW for Dryflex-C = 252.28 grams 4

 

 

 

 

 

From the above results, it can be concluded that the strongest lamination in
terms of puncture is the Dryflex-A The most susceptible to puncture is the
Dryflex-C. There are two major differences between these two laminations.
Dryflex-A has an additional 1.25 mil thickness layer of LLDPE, and an increase
in the outer layer (Valeron®) of 0.5 mil thickness in the lamination structure.

Nylons performed similarly in terms of puncture resistance. Nylon-A is a
thicker sample than the other two and performed the best among the nylons.
Nylon-C is the thinnest structure overall, but it contains the thickest layer of
LLDPE, contributing to the structure’s resistance to puncture.

in order to categorize the results, as described on Section 3.0, a ranking
or a scale was developed, (T able 10: Ranking Results Column). in this scale a
grade of ten was given to the best performance and a grade of zero to an
unacceptable performance. The scale was developed by using equal
increments of sixty grams, i.e. from 0 to 60 was rated as a '0', from 61 to 120
was rated as a '1' and so on. A ranking of 10 was given to Dryflex-A with an
energy absorbency of 601.44 grams while a ranking of 4 was given to Dryflex-C

with an energy absorbency of 252.28 grams.

3.4 Foil Delamination Test

The key step in laminating is the creation of a strong adhesive bond
between the films. Nevertheless, when foil is present, there is always the
possibility of having it fly out of the lamination when it is ripped. The bag can be

opened in two ways: by opening the seam or peeling, or by ripping the bag off.

31

A good lamination must be able to be opened by either method without creating
foil flakes.

The seam has been heat sealed (section 3.5), and it is expected to peel
easily all the way through the roll height, facilitating the use of the roll. When
performing this operation, if an adhesion problem is present in the lamination
structure, the foil might break and fly out of the lamination. If this happens, the
most probable event is that the foil will fly directly onto the roll’s surface, due to
the static effect generated. Foil particles are very small and cannot be easily
removed, causing serious contamination problems. One foil particle can
contaminate a whole section of the roll, and it will only be discovered after it has
been laminated inside the glass. This will create waste and loss for the
customer, as well as undesired complaints. For this reason, a test was
developed to evaluate this critical problem. The foil delamination test is an in-
house test that will provide information about the security of the foil adhesion in
the lamination. This test is designed to prevent the problem of having foil

particles flying out of the lamination when the bag is opened to use the polyvinyl
butyral roll.

3.4.1 Foil Delamination Test Description

Two methods have been developed to evaluate the foil adhesion in the
lamination structure. The first one will simulate what happens when the
lamination structure is opened along the heat-sealed seam. The second method

will simulate what will happen if the bag is ripped off the roll. These will be

32

named Method A and Method B. Method A is the regular 'T' test according to
ASTM D-1876-95, which will be covered in detail in Section 3.5 on testing the
heat seal properties. This method was used to evaluate how easily the foil flies
out of the lamination when opening. The second method, Method 8, also
evaluates the adhesion of the foil to the other layers. This one was an in-house

test, in which the following steps were used:

Step-1, Obtain a sample
Step-2, Stretch the sample
Step-3, Cut the sample
Step-4, Foil delamination

Step-5, Count the particles

Step-1: Obtain a sample of the lamination of about ten square inches as shown

in Figure 8.

Make sure this test is performed on a clean surface, with a solid color, i.e. black

or brown. Light colors like yellow or white would not allow contrast and would

make impossible to quantify the foil particles.

33

Figure 8: Lamination sample of ten square inches

 

 

 

Step-2: Grasp the lamination sample by the top two edges and manually apply
opposite forces to the edges until the lamination structure is noticeably
stretched. A desirable stretch for this test is between V. and V4 inch, as shown
in Figure 9. By stretching the area, the bonds in the lamination have been
weakened and broken, potentially allowing foil particles to fly out of the

lamination.

Figure 9: Stretched lamination sample

 

Step-3: Make a out about ‘A inch deep at the center of the stretched area with
scissors, (the cut is a simple out not a ‘V' shape cut) as shown in Figure 10.

This will facilitate the next step.

Figure 10: Cut to the lamination

 

Step-4: Propagate the cut made in Step 3. Grasp the stretched ends and apply
forces in opposite directions as shown in Figure 11. This will liberate all the foil

particles with a weak or a broken bond to the other substrates.
Step-5: Count the foil particles. Look carefully to the working surface described
in Step-1 and count the number of foil particles found. Categorize them into

none, low, medium of high as described below.

This part of the test is critical, due to the fact that polyethylene stretches.

That means all lamination structures having LDPE as a tie layer are susceptible

35

to foil flaking. Another contributor for failure during this test is the kind of cut
propagation when performing the last step. Laminations like Dryflex, with a
Valeron® layer as the outer layer, do not tears easily. Valeron is a cross
lamination of two layers, each one oriented at 90 degrees apart from each other
in the machine direction. This will allow for more broken bonds on the foil
adhered when tear than in the Nylons. Laminations like the Nylons propagate
easily, allowing for a minimum of bonds to be broken while propagating the cut.
This test was performed three times for each lamination. Each time a grade of:
none, low, medium or high was given to each lamination based on the results.
"None', meaning no foil particles were found after performing the test, was rated
as 0.1. 'Low', meaning one or two particles were found after performing the test,
was rated 1. “Medium”, meaning three to four particles were found after
performing the test, was rated 2; and a 'high" presence of foil particles was rated
as 3. High was defined as more than four foil particles were found after
performing the test. The scores for the three test pieces were summed for
Method A and Method B, and these two sums, added together to give the overall

SCOTS.

Figure 11: Foil Delamination

Foil Particles

 

3.4.2 Foil Delamination Test Results

The data for the foil delamination tests in this study on laminated film are
listed in Appendix C in Tables C1 to C7. A summary of the data is presented in
Table 11. The scores of the three samples by each method were added

together, and then the totals were added for the final result.

37

Table 11: Results of the Foil Delamination Test

 

Laminations Foil Delamination Results Ranking Results
Nylon-C = 0.60 10
Nylon-B = 2.4 9
Nylon-A = 3.3 8

Dryflex-C = 4.2 7
Tyvek® is = 5.1 6
Dryflex-B = 11 2
Dryflex-A = 14 0

 

 

 

 

From the above results, it can be concluded that the lamination least susceptible
to foil delamination is Nylon-C. This is due to two important factors. First, the
foil adheres to the nylon by a strong bond made by the thin layer of adhesive.
The second factor is the ease of tear propagation. Both the nylon and foil tear
easily. Once the cut is started, propagation continues without resistance. Since
the foil is very well bonded to the nylon, they behave as a single substrate. The
other nylon structures and the Dryflex-C perform excellently as well. Dryflex-A
performed the worst due to its strength properties and resistance in propagating
the cut.

in order to categorize the results, as described in Section 3.0, a ranking
or a scale was developed, (Table 11: Ranking Results Column). In this scale, a

grade often was given to the best performance (least foil delamination) and a

38

 

grade of zero to an unacceptable performance. The scale was developed by
using equal increments of 1.27 units, i.e. from 0 to 1.27 was rated as a “10", from
1.28 to 2.54 was rated as a ‘9' and so on. A ranking of 10 was given to Nylon-

C, which had minimal foil delamination.

3.5 Heat Seal Test

Packages that open by peeling the heat seal seem, rather than tearing,
are desired for many applications such as pouches and bags. Peel seals are
achieved by weakening the normal strength of a heat seal by reducing the
cohesive strength of the layer, the adhesion of the coating layers to the
substrate, or the degree of fusion during heat sealing (Osborn, 1992).

Hot tack is a term that denotes the degree of strength, or resistance to
peeling apart, that a sealant layer can develop while it is still hot after just being
released by the sealing bars. Widely used packaging films such as LDPE have
relatively poor hot tack. Low cost ethylene copolymer films such as EVA have
better hot tack than LDPE, and ionomer films have the highest hot tack of any
plastic film used in packaging. Outstanding heat sealing characteristics are the
primary advantage of the thicker coatings attainable by extrusion coating. The
specific characteristics are determined by the kind of sealant layer and the
thickness. LDPE is the most common and lowest cost choice. The minimum
sealing temperature for LDPE is about 120°C, while HDPE is higher at about

140°C. Where lower temperature sealing is required for higher packaging

39

machine speeds, ionomers with a minimum seal temperature of 104°C or EVA
coatings that seal at 65°C are used.

As the seal cools and hardens, it slowly develops its ultimate strength. A
strong seal is vital, since the bag must frequently withstand severe mechanical
stresses during distribution and handling. For this reason, this test was included
in the evaluation criteria of this study. The testing was performed according to
ASTM D1876-95, Standard Test Method for Peel Resistance of Adhesive (T -

Peel Test).

3.5.1 Heat Seal Test Description

This test method is primarily intended for determining the relative peel
resistance of adhesive bonds between flexible adherends by means of a T-type
specimen. The machine used for this test s the lnstron Universal Testing
Machine $0.005 lb. (load), :t0.0005 inch (extension). The first step is the
preparation of the laminated test panels (Figure 12). They consist of two flexible
adherends properly prepared and bonded together in accordance with the

adhesive manufacturer’s recommendation.

4O

Figure 12: Test Panel

76 mm
unbonded

 

The test panels were 152 mm (6 in.) wide by 305 mm (12 in.) long, but
were bonded only over approximately 241 mm (9 in.) of their length. Test panels
of the same dimension may be cut from larger, fully laminated panels. Next the
bonded panels were cut into 25 mm (1 in.) wide test specimens as shown in
Figure 13. The 76 mm (3 in.) long unbonded ends were bent apart,
perpendicular to the glue line, for clamping in the grips of the lnstron machine.

A total often specimens were tested for each lamination sample.

41

Figure 13: Test Specimen

E

 

76mm

 

 

Test
Specimen

 

 

Once the test specimen was prepared, the unbonded ends were clamped
in the grips of the lnstron machine. A rate of deformation of 254 mm (10 in.)lmin
was applied. The peak load per unit width of bond line required to produce
progressive separation of two bonded, flexible adherends was measured for

each lamination structure.

42

3.5.2 I-leat Seal Test Results

The data for the heat seal tests in this study on laminated film are listed in
Appendix D in Tables D1 to D7. These tables list the results of the average
peak peeling load in pounds per inch for each lamination structure. A summary

of the data is presented in Table 12.

Table 12: Results of the Heat Seal Test

 

Laminations Heat Seal Results Ranking Results
Dryflex-A = 14.29 lbfrn. 10
Dryflex-B = 13.86 Ibfin. 10
Nylon-C = 13.54 lbfln. 10
Tyvek® is = 1 1.81 lbfln. 9
Nylon-A = 10.98 Ibfrn. 8
Nylon-B = 9.73 lbfrn. 7
Dryflex-C = 8.17 lbfrn. 6

 

 

 

 

Laminations using LLDPE as the sealant layer provide the highest strength in
terms of peeling. However, they also exhibit the highest level of adhesive
failure. Adhesive failure was identified in Section 3.4 (Foil Delamination Test) as
a critical problem for this lamination. On the other hand, nylon structures
performed as well as the Dryflex A & B, but did not show adhesive failure. The

Tyvek® lamination failed most of the time in cohesion, but exposed the foil in

43

 

one occasion. Dryflex-C, with the sealant layer made of extruded LDPE, showed
the lowest strength when peeled. This is good and bad at the same time, good
because it requires the least amount of force to open the package and bad,
because the seal is more susceptible to being opened prematurely. Dryflex-C
was the only lamination that consistently failed in cohesion.

in order to categorize the results, as described in Section 3.0, a scale was
developed, (Table 12: Ranking Results Column), with a grade often given to the
best performance (highest strength when peeled) and a grade of zero to an
unacceptable performance. The scale was developed by using equal
increments of 1.29 units, i.e. from 0 to 1.29 was rated as a '1', from 1.30 to 2.59
was rated as a '2' and so on. A ranking of 10 was given to Dryflex-A, Dryflex-B

and Nylon-C.

3.6 Performance on Pallets Test

One of the most critical tests for the laminations is the performance of the
bag during distribution on the plastic pallet. It is critical because the laminated
bag can be broken during transportation and handling. If this happens, the
usability of the roll is in danger, as moisture gain can cause the rolls to become
a piece of plastic as solid as concrete. The two major factors influencing the
results of this test are: the extended cores and the shift of the load.

Most of the time during the manufacturing process, in the winder, the roll
is wounded on extended cores (Figure 14). This facilitates the unwinding

process for the customer. The extension can be anything between V4 and 318 of

44

an inch, on the bottom side, and here will be the critical problem. The whole
weight of the roll will rest on the core, creating strong friction against the plastic
pallet If the lamination is weak or susceptible to friction, this results in the
creation of holes and cuts, which allow moisture to penetrate into the polyvinyl
butyral roll.

Figure 14: Extended Core

 

 

 

/

- Extended Core

The second major cause of poor performance on the plastic pellets is the
load shifting from its original position. If the lamination is too brittle or too stiff, it

will tend to break under these conditions due to stress exceeding tear strength.

45

3.6.1 Performance on Pallets Test Description

The performance on plastic pallet test is a dynamic test. It involves a
simulation of the distribution environment in which two rolls are placed on top of
the plastic pallet and submitted to shocks and vibrations when handled by a fork
truck The ideal test would use the standard ASTM D 4169-93 (Standard
Practice for Performance Testing of Shipping Containers and Systems), but it
was impossible to perform this test due to its cost and lack of resources.

Using this concept as a model, a dynamic test was developed. The test
was performed on wood and on plastic pallets. it consisted of loading two rolls
on a pellet (the heaviest rolls weigh approximately 1200 lb. each), and then

packaging them with all the additional package elements as explained in Table

13.

Table 13: Packaging Elements for Wood and Plastic Pallets

 

sidewall (cardboard)
cushion pad (cardboard)
bottom tray (cardboard)

wood pallet

 

 

Wood Package Plastic Pallets
strapping strapping
top tray (cardboard) top pallet (HDPE)
pad (cardboard) bottom pallet (HDPE)

 

The load is then picked up with a forklift (Figure 15), and submitted to about five

minutes of dynamic shock and vibration.

Figure 15: Loaded Forklift

 

 
   

l

W

 

 

  

There were two kinds of test, the moderate test and the severe test. Both
tests used the same route, which included driving the forklift with the package
over a rough road with holes, bumps and crossing over railroad lines. The
moderate test lasted for three minutes at a speed of approximately 2 to 3 miles

per hour. The severe test consisted of the same elements as the moderate test,

47

but at a smed of approximately 5 to 6 miles per hour. Also, the severe test
crossed twice over railroad lines and lasted six minutes. At the end of the test
the rolls were removed from their bags and they were inspected for damage.
Each test always used a new bag.

in order to have enough information relevant to the different environments
to which the packaged bag may be exposed, the test was concluded using wood
and plastic pallets. Each pellet was exposed to the moderate and the severe
test. The criterion used to rate this test was based on the amount of bag
damage (creation of holes or cuts to the bag at the bottom of the roll). After the
test, each hole or cut was counted, multiplied by the test rating factor (severe=5,
moderate=10) and the tests added. in the severe test, the probabilities of

failure are higher than in the moderate test.

3.6.2 Performance on Pallets Test Results

The data for the performance on pallet tests in this study on laminated
film are listed in Appendix E in Tables E1 to E7. These tables list the number of
failures found in each test. A summary of the data is presented in Table 14.

The severe test is an overkill test; the moderate test is similar to the
distribution environment. For this reason, the number of failures (holes or cuts)
in the moderate test was multiplied by ten (10), while the number of failures in
the severe test was multiplied by five (5). Each test was performed twice, for
each type of pallet, for a total of eight different test results per kind of bag. The

totals for the two pallet types were added together to give the score for the test.

48

Table 14: Results of the Performance on Pallets Test

 

Laminations Damage Score Ranking Results
Dryflex-A = 0 10
Tyvek® is = 5 1o
Dryflex-B = 5 10
Dryflex-C = 10 9
Nylon-A = 45 4
Nylon-C = 55 2
Nylon-B = 75 o

 

 

 

 

From the data for the performance on the wood pellets, it can be
concluded that this test is not critical. None of the seven laminations were
damaged in either test. All the laminations performed very well on the wood
pellets. On the other hand, on plastic pallets the result varies. The least
susceptible lamination structure to punctures, holes or cuts is the Dryflex-A, with
excellent results on both pallets. Dryflex-B and Tyvek® perform similarly; they
both are also rated as excellent Dryflex-C performed acceptably. Nylons
performed poorly on plastic pallets, but excellently on wood pellets.

In order to categorize the results, as described in Section 3.0, a scale was
developed (Table 14: Ranking Results Column), with a rank often given to the
best performance (least failures) and a rank of zero to the worst performance.
The scale was developed by using equal increments of 6.81, i.e. from 0 to 6.81

was rated as a '10”, from 6.82 to 13.63 was rated as a '9' and so on. A ranking

49

 

of 10 was given to Dryflex-A, Dryflex-B and Tyvek®. On the other hand, Nylon-

B was rated zero, as it had the highest failure score.

3.7 Sliding. Folding and Label Adhesion Test

Another important criterion for the comparison of the alternative materials
is their fitness for use. The bag must be used effectively for whatever it was
designed to do, and it must perform acceptably. Therefore, it was necessary to
perform a test which considered the day to day operations involving the bag.
Sliding, Folding and Label Adhesion are in—house tests that will provide
information regarding routine handling. These are the things the operators will
do to the bags repeatedly. They are performed sequentially in the same order
they are written.

During the sliding operation, the operator opens the bag and then covers
the roll with it, protecting the roll from any possible damage. At this point the
coefficient of friction (COF) between the LDPE film covering the roll and the
material inside the bag is critical. If the material has a high COF, the bag will be
hard to insert on the roll. On the other hand a low COF will facilitate the
operation. Once the bag covers the roll, it is folded, adjusting it to the roll size.

The folding operation is performed manually and all the folds are secured
with adhesive tape. At this point the manageability of the bag is important. A
rigid or stiff bag can be hard to work with. On the other hand if the bag folds
easily it will make the manufacturing operation easier. The last, but not least

important, is the product identification or labeling Operation. After folding the

50

bags, a label is placed on the side of the lamination for the proper identification
of the roll. This label will travel with the product, retaining the identity of the

formulation until it reaches the customer.

3.7.1 Sliding, Folding and Label Adhesion Test Description

The method used to perform this test was based on the repetition of the
sliding, folding and label adhesion operation. Each operation was performed
three times for each lamination by the same operator. Similarly to section 3.3
(foil delamination), each time a grade of: none, low, medium or high was given to
each lamination. 'None' means no problems in performing the operation, (easy
to slide the bag over the roll, easy to fold, and the label adheres well), and was
rated as 0.1. 'Lovr was rated as 1, and means the operator found a minor
problem while performing the operation. ‘Medium’ was rated as 2, meaning the
operator had more trouble in performing the operations than in ‘Low'. 'High”
means high difficulty in performing the operation and was rated as 3.

Each test was performed three times for each lamination. The results of
each separate test were individually added and then added together. The
arithmetical addition was taken as the result of the sliding, folding and label

adhesion test for each lamination.

3.7.2 Sliding, Folding and Label Adhesion Test Results
The data for each sliding, folding and label adhesion test in this study are

listed in Appendix F in Tables F1 to F7. These tables list the results of the

51

subjective evaluation by an experienced operator, in terms of how difficult it was

to perform the operation. A summary of the data is presented in Table 15.

Table 15: Results of the Sliding, Folding and Label Adhesion Tests

 

Laminations Test Results Ranking Results
Dryflex-C = 1.8 9
Nylon-C = 5.5 7
Nylon-B = 8.3 5
Tyvek® is = 9.3 5
Nylon-A = 9.3 5
Dryflex-B = 12.3 3
Dryflex-A = 18.3 0

 

 

 

 

From the above results it can be concluded that the easiest lamination to work
with is the Dryflex-C. This lamination folds better than any other lamination
evaluated; in addition it slides very easily. On the other hand, Dryflex-A is the
most difficult lamination to work with. The outer layer of this lamination is very
stiff and hard to shape to the roll size. Nylon structures perform acceptably once
again. The thickest nylon (Nylon-A), was the most difficult to work with.
Regarding the label adhesion test, the results showed no difference in adhering

the label from lamination to lamination. The Tyvek® structure has the most

52

 

roughness on its surface, but this was not significant enough to interfere with the
operation.

In order to categorize the results, as described in Section 3.0, a scale was
developed (Table 15: Ranking Results column), with a grade often given to the
best performance and a grade of zero to an unacceptable performance. The
scale was developed by using equal increments of 1.66 units, i.e. from 0 to 1.66
was rated as a ‘10”, from 1.67 to 3.33 was rated as a '9' and so on. Neither
lamination obtain a “10' on this test. A ranking of 9 was given to Dryflex-C which
was the most manageable lamination, while a ranking of 0 was given to Dryflex-

A which was the most difficult lamination to handle.

3.8 Water Vapor Transmission Rate (WVTR) Test

This test was performed according to ASTM standard F 1249-90 (Water
Vapor Transmission Rate Through Plastic Film and Sheeting Using a Modulated
Infrared Sensor). This test method covers a procedure for determining the rate
of water vapor transmission through flexible barrier materials. The method is
applicable to sheets and films up to 3mm (0.1 in.) in thickness, consisting of
single or multilayer synthetic or natural polymers and foils, including coated
materials. WVTR is the rate of water vapor flow normal to the surfaces, under
steady-state conditions, per unit of area. The units of the test are grams divided
by meters squared per day (9 I M2 day).

The purpose of the test is to obtain reliable values for the WVTR of the

lamination structures. WVTR is an important property of packaging materials

53

and can be directly related to the shelf life and packaged product stability. In
fact the shelf life of the polyvinyl butyral is determined by the WVTR of the
lamination and the damage it may sustain. The equipment used for this

experiment was the Permatran-W machine.

3.8.1 WVTR Test Description

This test method was performed by an expert on the equipment, a
graduate student from the Michigan State University School of Packaging. The
test procedure to perform this test is described in detail in the ASTM standard.

The general equation to calculate WVTR is:

WVRT = ( C) x (ES - EO)

where:
C = Calibration factor expressing rate as a function of voltage or mV.
The
value of C is derived from test of a known reference film.
E0 = Permeation system zero level voltage
ES = Equilibrium voltage obtained with the test specimen

3.8.2 WVTR Test Results
The data for the WVTR tests for this study on laminated film are listed in

Appendix G in Tables G1 to G7. These tables list average WVTRs for two

samples per lamination. A summary of the data is presented in Table 16.

Table 16: Results of the VWTR Test

 

Laminations WVTR Results Ranking Results
Dryflex-C = 0.001 (g r M2 day) 10
Nylon-A = 0.194 (g r M’ day) 6
Nylon-B = 0.207 (g r M2 day) 5
Nylon-C = 0.221 (g r M2 day) 5
Dryflex-B = 0.263 (g r M1 day) 4
Tyvek® is = 0.435 (g r M2 day) 0
Dryflex-A = no data (9 l M2 day) 4

 

 

 

 

As the results reflect, the best lamination structure in terms of WVTR is
the Dryflex-C with an average level of 0.001 g I M2 per day. Tyvek® performed
the poorest. Since all the laminations contain the same amount of foil as the
barrier layer, this may happened due to higher diffusion of moisture particles
though the material itself or though the seal. Nylon laminations, overall,
performed as well as Dryflex laminations. Nylon-A, with Saran® coating,

performed the best of the nylons. The test was not performed on the Dryflex-A

55

 

structure. Since it is manufactured identically and has very similar composition
to Dryflex B, it was assigned the same ranking as Dryflex-B.

In order to categorize the results, as described in Section 3.0, a scale was
developed (T able 16: Ranking Results Column), with a grade often given to the
best performance (lowest VWTR level) and a grade of zero to the lowest
performance. The scale was developed by using equal increments of 0.0396
units, i.e. from 0 to 0.0396 was rated as a '10", from 0.0397 to 0.0792 was rated
as a '9' and so on. A ranking of 10 was given to Dryflex-C, while a ranking of 0
was given to Tyvek®. This does not mean that Tyvek® is unacceptable for this
application. This result means it performed the worst when compared to the

other laminations during this WVTR test.

3.9 Summary of the Results

This section contains the summary of the results of all the testing
performed on the lamination structures (discussed in detail in Section 3). Table
17 (Summary of the Test Results) contains the results of each independent test
for the laminations. An overall ratings summary is presented in Table 18
(Summary of the Rating Results). The independent rating from each test were
added to provide a tabulated representation of the overall performance among

the alternatives considered.

 

Table 17: Summary of the Test Results

 

 

 

 

 

 

 

 

 

 

 

 

 

57

 

 

 

 

Tested Laminations Structures
Test DryIss-A omen-s Drylss-c Nylon-A Nylon-D Nylon-C ryvurrs
cm (holes) 37.0 20.3 10.7 11.3 0.3 14.7 17.7
cum 3473.43 0300.54 0347.70 0307.30 0503.04 0401.34 s770.07
Dut Drop (Pm Resumes) 001.44 g 521.75 g 252.28 g 413.93 g 3.53 g “.53 g MAO g
Fol oasis-non m) 14 11 42 3.3 24 0.0 5.1
Hut su ram.) 1420 13.00 0.17 10.00 0.73 13.54 11.01
Performance! Pits (tolss) 0 5 10 45 75 55 5

sun, rm use Mission 10.3 123 1.0 0.3 0.3 5.5 0.3

wer r Pin l-iolss (glM ”rd-y) x 0.203 0.001 0.104 0207 0221 0.435

Table 18: Summary of the Rating Results
Tested Laminations Structures
Test ma Dryflex-B Dryflex-C Nonn-A Nylon-D Nyion-C rm

cm 10 0 4 3 2 4 4
cum 4 5 0 0 2 4 0
Dart Drop (Puma Resistance) 10 8 4 5 4 5 4
Fol Dehmhdion 0 2 7 0 0 10 0
Hour Sad 10 10 0 0 7 10 0
W 10 10 0 4 0 2 10
em, Fm Labor Am 0 3 0 5 0 7 5
WVTR I an Holes 4 4 10 0 , 5 5 0
Over! Perform-ice 48 50 55 48 :5 48 38

 

 

4.0 Conclusions

Considering the complete performance analysis covering all the
manufacturing operations, the results show better performance from the Dryflex-
B and Dryflex-C stmctures, compared to the nylons and Tyvek®. Nylon
laminations are suitable for corrugated packages, but do not have the strength
needed to be used on plastic pallets. The other laminations are also good, but
they possess weak points. The Tyvek® lamination is excellent from a
performance perspective, but inefficient from a cost point of view.

The lamination with the overall best performance was the Dryflex-C. The
main reasons for this result were: its manageability (Sliding, Folding and Label
Adhesion), the Foil Delamination test, and the WVTR test. In all these tests the
lamination reached the top score and at the same time it performed very well in
the performance on plastic pallets test. Dryflex-B was the second best
performer. Dryflex-A is the strongest structure, but it is the most difficult to work
with. its stiffness makes the structure not desirable for manageability. On the
other hand, Dryflex-C, is more balanced between the three Dryflex alternatives.
Dryflex-A is too rigid to be used and also has the delamination problem.

Nylon-C and Nylon-A performed the best of the nylons with scores of 48
and 46 points respectively. The good performance of Nylon-C structure is due
to the thicker LLDPE layer this structure possesses. This layer enhance the
structure allowing good results in the Dart Drop and Heat Seal test. Tyvek®,

had the second lowest score overall for two major reasons; the expensive cost

58

and the water vapor transmission rate results. Dryflex-C had the best overall
performance results on the mechanical and physical properties evaluated in this
study. The lamination with the poorest overall performance was Nylon-B.

The mechanical properties of a lamination structure can be improved by
adding a LLDPE layer. It is appropriate to mention that a layer of LLDPE adds to
the structure desirable properties against puncture, in this study represented by
the dart drop test. All the samples that contained the LLDPE layer performed six
and above in the ranking scale, while those which did not have it performed
lower, with the exception of Nylon-A, which has a thicker nylon layer.

This study provide guide lines to objectively evaluate and select different
numbers of alternatives based on the lamination performance. The same
concepts can be adapted to other applications, in which it will be necessary to
select one alternative among others. During this study there were some critical
test and some that have no impact on the overall performance for the
laminations. If this study is performed again, changes to the performance testing
section should be consider. Experiments like performance on wood pellets and
label adhesion were not relevant to the final score. On the other hand, test like:
stress and strain analysis, aro burst test and gas permeability should be added

and correlate their results to mechanical and physical properties.

59

APPENDICES

APPENDIX A

61

Table A1: Capping Operation Test Results of the Dryflex-A Structure

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Capping Test Capping Test Capping Test Average std.
data 1 data 2 data 3
35 37 44 38.67 4.73
Table A2: Capping Operation Test Results of the Dryflex-B Structure
Capping Test Capping Test Capping Test Average std.
data 1 data 2 data 3
31 ’ 27 30 29.33 2.00
Table A3: Capping Operation Test Results of the Dryflex-C Structure
Capping Test Capping Test Capping Test Average std.
data 1 data 2 data 3
15 19 16 16.67 2.08

 

 

 

 

 

62

 

 

 

Table A4: Capping Operation Test Results of the Nylon-A Structure

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Capping Test Capping Test Capping Test Average std.
data 1 data 2 data 3
1 1 10 13 1 1.33 1 .53
Table A5: Capping Operation Test Results of the Nylon-B Structure
Capping Test Capping Test Capping Test Average std.
data 1 data 2 data 3
8 9 11 9.33 1.25
Table A6: Capping Operation Test Results of the Nylon-C Structure
Capping Test Capping Test Capping Test Average std.
data 1 data 2 data 3
13 16 15 14.67 1.53

 

 

 

 

 

63

 

 

 

Table A7: Capping Operation Test Results of the Tyvek® Structure

 

 

 

Capping Test Capping Test Capping Test Average std.
data 1 data 2 data 3
17 22 14 17.67 4.04

 

 

 

 

 

 

APPENDIX B

Table B.1: Dart Drop Results of the Dryflex-A Structure

 

rams R 1234587891011121314151617181920Ni

.43 7 X
38.18
22.93
7.68
92.43
77.18
1.93
.68 O 11

Arousal?
(T
o
o
X
X
)<
X
X
“MANN—s

 

 

 

OANwhu'I
ONNOQU’I

15 23

 

Failure Weight

Wf=Wo+("W(AIN-112))

Where W0 is missile weight with an i value of 0 = 577.18 grams
Where A is the sum of the Ni values = 23

Where N is the sum of the Ni's = 11

Where 1‘W is the weight increment = 15.25 grams

Wf for Dryflex-A = 601.44 grams

 

Table 8.2: Dart Drop Results of the Dryflex-B Structure

 

rams R

9.20 9
3.95
31.70 7 x x
19.45 is 0 0 x
7.20 5
494.95 4
402.70 3
470.45 2
450.20 1
445.95 I0

 

 

 

1234587891011121314151817181920212223

 

Failure Weight

Wf=Wo+("W(AIN-1I2))

Where W0 is missile weight with an i value of 0
Where A is the sum of the iNi values

Where N is the sum of the Ni's

Where "W is the weight increment

Wf for Dryflex-B =

= 507.20 grams
= 16

= 11

= 15.25 grams

521.76 grams

67

 

Table 83: Dart Drop Results of the Dryflex-C Structure

 

 

 

[grams R1234587891011121314151817181920Ni i iNi
823.95 7
308.70 '8
293.45 5 X 1 4 4
278.20 4 0 X 1 3 3
262.95 3 X X X 0 X 4 2 8
247.70 2 0 X X X 0 0 0 3 1 3
232.45 1 X 0 0 0 1 0 0
217.20 0 0
10 10 18
N A

 

 

 

Failure Weight

Wf=Wo+("W(AlN-1I2))

Where W0 is missile weight with an i value of 0 = 232.45 grams
Where A is the sum of the iNi values = 18

Where N is the sum of the Ni's = 10

Where "W is the weight increment = 15.25 grams

Wf for Dryflex-C = 252.28 grams

Table B.4: Dart Drop Results of the Nylon-A Structure

 

[grams R1234567891011121314151617181920Ni i iNi

O—INOD
000mm

 

 

 

 

 

Failure Weight

VVf=Wo+("W(AIN-1/2))

Where W0 is missile weight with an i value of 0 = 400.20 grams
Where A is the sum of the iNi values = 14

Where N is the sum of the Ni's = 10

Where "W is the weight increment = 15.25 grams

Wf for Nylon-A 413.93 grams

69

Table 85: Dart Drop Results of the Nylon-B Structure

 

 

 

 

 

 

Iqrams R 123456 78910111213141516171819202122
339.20
323.95 7 X X
308.70 16 0 x X 0 x x x
293.45 5 X 0 0 0 X 0 0 X
278.20 4 0 0 0
262.95 3 0 Ni i iNi
247.70 2 0
232.45 1 2 2 4
217.20 '0 5 1 5
3 0 0
10 3 9
N A
Failure Weight

Wf=Wo+("W(AlN-1l2))

Where W0 is missile weight with an i value of 0 = 293.45 grams
Where A is the sum of the iNi values = 9

Where N is the sum ofthe Ni's =10

Where "W is the weight increment = 15.25 grams

Wf for Nylon-B 299.53 grams

70

Table B.6: Dart Drop Results of the Nylon-C Structure

 

 

 

Lrams R1234567891011121314151617181920Nii
461.20 7 Ni i
445.95 I6
430.70 5 X 1 3
415.45 4 X 0 X 2 2
400.20 3 X 0 X X 0 X X 5 1
384.95 2 X 0 X 0 0 0 0 2 0
369.70 1 0 0 10
354.45 '0

N

 

 

 

Failure Weight

Wf=Wo+("W(AIN-112))

Where W0 is missile weight with an i value of 0 = 384.95 grams
Where A is the sum of the iNi values = 12

Where N is the sum of the Ni's = 10

Where "W is the weight increment = 15.25 grams

Wf for Nylon-C 395.63grams

71

Table 87: Dart Drop Results of the Tyvek® Structure

 

 

Igrams R123458789101112131415181718192021Ni
323.95 7 X 1

308.70 )6 X X 0 X X 4

293.45 5 0 0 0 X 0 X 2

278.20 4 0 X X X 0 3

262.95 3 I0 0 0 0

247.70 2 10
232.45 1 N
217.20 I0

 

 

O-INW

<3wa

 

Failure Weight

Wf=Wo+("W(AlN-1I2))

Where W0 is missile weight with an i value of 0 = 278.2 grams
Where A is the sum of the iNi values = 13

Where N is the sum of the Ni's =10

Where "W is the weight increment = 15.25 grams

Wf for Tyvek® is = 290.40 grams

72

 

APPENDIX C

73

Table C.1: Foil Delamination Results of the Dryflex-A Structure

 

 

 

 

 

 

 

 

Classification Rate Method-A Method-B
None 0.1
Low 1
Medium 2 X
High 3 X
None 0.1
Low 1 X
Medium 2
High 3 X
None 0.1
Low 1
Medium 2 X
High 3 X
5 9
14

Table C.2: Foil Delamination Results of the Dryflex-B Structure

 

 

 

 

 

 

 

 

 

 

Classification Rate Method-A Method-B
None 0.1
Low 1 X
Medium 2 X
High 3
None 0.1
Low 1 X
Medium 2 X
High 3
None 0.1
Low 1
Medium 2 X
High 3 X
4 7
1 1

74

Table C.3: Foil Delamination Results of the Dryflex-C Structure

 

 

 

 

 

 

 

 

Classification Rate Method-A Method-B
None 0.1
Low 1 X X
Medium 2
High 3
None 0.1 X
Low 1 X
Medium 2
High 3
None 0.1 X
Low 1 X
Medium 2
, High 3
1 .2 3
4.2

Table 0.4: Foil Delamination Results of the Nylon-A Structure

 

 

 

 

 

 

 

 

75

Classification Rate Method-A Method-B
None 0.1 X
Low 1 X
Medium 2
High 3
None 0.1 X
Low 1 X
Medium 2
, High 3
None 0.1 X
Low 1 X
Medium 2
High 3
0.3 3
3.3

 

 

Table C.5: Foil Delamination Results of the Nylon-B Structure

 

 

 

 

 

 

 

 

 

Classification Rate Method-A Method-B
None 0.1 X X
Low 1
Medium 2
, High 3
None 0.1 X
Low 1 X
Medium 2
, High 3
None 0.1 X
Low 1 X
Medium 2
, High 3
0.3 2.1
2.4

Table C.6: Foil Delamination Results of the Nylon-C Stmcture

Classification Rate Method-A Method-B

 

None 0.1 X X
Low 1
Medium 2
, High 3

 

None 0.1 X X
Low 1
Medium 2

3

High

 

None 0.1 X X
Low
Medium

‘ High

 

 

 

 

(QM-e

 

 

0.3 0.3
0.6

76

Table C.7: Foil Delamination Results of the Tyvek® Structure

 

 

 

 

 

 

 

 

77

Classification Rate Method-A Method-B

None 0.1

Low 1 X X
Medium 2
High 3
None 0.1

Low 1 X X
Medium 2
High 3

None 0.1 X

Low 1 X
Medium 2
HiLh 3

2.1 3

5.1

 

APPENDIX D

78

Table D1: Heat Seal Results of the Dryflex-A Structure

 

 

 

Test # Load Peak average
peeling load (ft/1n)

1 10 in.lmln 12.6

2 10 in.lmin 13.5

3 10 in.lmln 14.3

4 10 in.lmin 16.7

5 10 in.lmin 13.4

6 10 in.lmin 15.6

7 10 in.lmin 13.7

8 10 in.lmin 16.2

9 10 in.lmin 12.2
10 10 in.lmin 14.7
Average 14.29
std. 1.50

 

 

 

Table 0.2: Heat Seal Results of the Dryflex-B Structure

 

 

 

Test # Load Peak average peeling
load (#lin)

1 10 in.lmin 14.3

2 10 in.lmin 13.5

3 10 in.lmin 15.3

4 10 in.lmin 12.6

5 10 in.lmin 13.7

6 10 in.lmin 14.2

7 10 in.lmin 14.6

8 10 in.lmin 12.3

9 10 in.lmin 13.4
10 10 in.lmin 14.7
Average 13.86
std. 0.94

 

 

79

 

Table 03: Heat Seal Results of the Dryflex-C Structure

 

 

 

 

Test it Load Peak average peeling
load (#lin)

1 10 in.lmin 11.2

2 10 in.lmln 7.2

3 10 in.lmin 5.9

4 10 in.lmin 6.3

5 1O ln./min 7.0

6 10 in.lmin 12.2

7 10 in.lmin 6.3

8 10 in.lmin 8.3

9 10 in.lmin 6.5
10 10 in.lmin 10.8
Average 8.17
std. 2.35

 

Table 0.4: Heat Seal Results of the Nylon-A Stmcture

 

 

 

 

Test # Load Peak average peeling
load (ft/1n)
1 10 in.lmin 10.3
2 10 in.lmin 12.4
3 10 in.lmin 11.7
4 10 in.lmin 10.8
5 10 in.lmin 12.1
6 10 in.lmin 9.6
7 10 in.lmin 10.3
8 10 in.lmin 9.7
9 10 in.lmin 11.1
10 10 in.lmin 11.8
Average 10.98
std. 1.00

 

 

 

Table D5: Heat Seal Results of the Nylon-B Structure

 

 

 

Test # Load Peak average peeling
load (#lin)

1 10 in.lmin 9.0

2 10 in.lmln 9.8

3 10 in.lmin 10.4

4 10 in.lmin 10.6

5 10 in.lmin 7.6

6 10 in.lmin 10.8

7 10 in.lmin 10.1

8 10 in.lmin 8.6

9 10 in.lmin 9.9
10 10 in.lmin 10.5
Average 9.73
std. 1.03

 

 

Table D6: Heat Seal Results of the Nylon-C Structure

 

 

 

Test it Load Peak average peeling
load Mn)

1 10 in.lmin 15.2

2 10 in.lmin 14.6

3 10 in.lmin 14.2

4 10 in.lmin 1 1.6

5 10 in.lmin 12.8

6 10 in.lmin 12.7

7 10 in.lmin 10.3

8 10 in.lmin 18.2

9 10 in.lmin 12.6
10 10 in.lmin 13.2
Average 13.54
std. 2.17

 

 

81

 

 

Table D7: Heat Seal Results of the Tyvek® Structure

 

 

 

Test # Load Peak average peeling
load (#lin)
1 10 in.lmin 11.6
2 10 in.lmin 10.8
3 10 in.lmin 13.5
4 10 in.lmin 9.8
5 10 in.lmin 11.7
6 10 in.lmin 13.1
7 10 in.lmin 12.6
8 10 in.lmin 10.9
9 10 in.lmin 12.4
10 10 in.lmin 11.7
Average 11.81
std. 1.13

 

 

82

 

APPENDIX E

83

Table E.1: Performance on Pallets Results of the Dryflex-A Structure

 

 

 

 

 

 

 

 

Test severity Rate Wood Pellet Plastic Pallet
it holes or cuts # holes or cuts
Moderate 10 0
Severe 5 0
Moderate 10 0 0
Severe 5 0 0
O 0
0

Table E.2: Performance on Pallets Results of the Dryflex-B Structure

 

 

 

 

 

 

 

Test severity Rate Wood Pellet Plastic Pallet

it holes or cuts # holes or cuts
Moderate 10 0 0
Severe 5 0 1
Moderate 10 0 0
Severe 5 0 0
0 5
5

Table E.3: Performance on Pallets Results of the Dryflex-C Structure

 

 

 

 

 

 

 

 

 

Test severity Rate Wood Pellet Plastic Pallet
if holes or cuts it holes or cuts

Moderate 10 0 0
Severe 5 0 1
Moderate 10 0 0

’ Severe 5 0 1
0 10
10

Table E.4: Performance on Pallets Results of the Nylon-A Structure

 

 

 

 

 

 

 

 

Test severity Rate Wood Pellet Plastic Pallet
# holes or cuts # holes or cuts

Moderate 10 0 1
Severe 5 0 2
Moderate 10 0 1
Severe 5 0 3

0 45

45

Table E.5 Performance on Pallets Results of the Nylon-B structure

 

 

 

 

 

 

 

 

Test severity Rate Wood Pellet Plastic Pallet
# holes or cuts it holes or cuts

Moderate 10 0 2
Severe 5 0 3
Moderate 10 0 2
Severe 5 0 4
0 75
75

Table E.6: Performance on Pallets Results of the Nylon-C Structure

 

 

 

 

 

 

 

 

Test severity Rate Wood Pellet Plastic Pallet
# holes or cuts # holes or cuts

Moderate 10 0 1
Severe 5 0 2
Moderate 10 0 2
Severe 5 0 3

0 55

55

85

Table E.5: Performance on Pallets Results of the Tyvek® Structure

 

 

 

 

 

 

 

Test severity Rate Wood Pallet Plastic Pallet
# holes or cuts fl holes or cuts
Moderate 10 0 0
Severe 5 0 1
Moderate 10 0 0
Severe 5 0 0
0 5

 

APPENDIX F

87

Table F .1:
Structure

 

 

 

 

 

 

 

 

 

 

Table F .2:
Structure

 

 

 

 

 

 

 

 

 

 

Sliding Folding and Label Adhesion Results of the Dryflex-A
Classification Rate Sliding Folding Label
Adhesion
None 0.1 X
Low 1
Medium 2
High 3 X X
None ~ 0.1 X
Low 1
Medium 2
High 3 X X
None 0.1 X
Low 1
Medium 2
High 3 X X
9 9 0.3
18.3
Sliding Folding and Label Adhesion Results of the Dryflex-B
Classification Rate Sliding Folding Label
Adhesion
None 0.1 X
Low 1
Medium 2 X X
High 3
None 0.1 X
Low 1
Medium 2 X X
High 3
None 0.1 X
Low 1
Medium 2 X X
High 3
6 6 0.3
12.3

Table F.3: Sliding Folding and Label Adhesion Results of the Dryflex-C

 

 

 

 

 

 

 

 

 

Structure
Classification Rate Sliding Folding Label
Adhesion
None 0.1 X X X
Low 1
Medium 2
High 3
None 0.1 X X X
Low 1
Medium 2
High 3
None 0.1 X X
Low 1 X
Medium 2
High 3
1 .2 0.3 0.3
1 .8

Table F .4: Sliding Folding and Label Adhesion Results of the Nylon-A Structure

 

 

 

 

 

 

 

 

 

Classification Rate Sliding Folding Label
Adhesion
None 0.1 X
Low 1 x
Medium 2 X
High 3
None 0.1 X
Low 1 X
Medium 2 X
High 3
None 0.1 X
Low 1 X
Medium 2 X
High 3
5 4 0.3
9.3

89

 

 

Table F.5: Sliding Folding and Label Adhesion Results of the Nylon-B Structure

 

 

 

 

 

 

 

 

 

Classification Rate Sliding Folding Label
Adhesion
None 0.1 X
Low 1 X X
Medium 2
High 3
None 0.1 X
Low 1
Medium 2 X X
High 3
None 0.1 X
Low 1 X X
Medium 2
High 3
4 4 0.3
8.3

Table F.6: Sliding Folding and Label Adhesion Results of the Nylon-C Structure

 

 

 

 

 

 

 

 

 

Classification Rate Sliding Folding Label
Adhesion
None 0.1 X
Low 1 X X
Medium 2
High 3
None 0.1 X X
Low 1 X
Medium 2
High 3
None 0.1 X X
Low 1
Medium 2 X
High 3
1.2 4 0.3
5.5

 

 

Table F .7: Sliding Folding and Label Adhesion Results of the Tyvek® Structure

 

 

 

 

 

 

 

 

 

Classification Rate Sliding Folding Label
. Adhesion
None 0.1 X
Low 1 X X
Medium 2
High 3
None 0.1 X
Low 1 X
Medium 2 X
High 3
None 0.1 X
Low 1
Medium 2 X X
High 3
5 4 0.3
9.3

91

 

APPENDIX C

92

Table G.1: WVTR Results of the Dryflex-A Structure

 

 

 

 

 

Lamination Source Result (g I M2 day)
Dryflex-A MSU-PKG No data
Dryflex-A MSU-PKG No data

(g r M2 day)

Table 6.2: WVTR Results of the Dryflex-B Structure

 

 

 

 

 

Lamination Source Result (9 l M2 day)
Dryflex-B MSU-PKG 0.270
Dryflex-B MSU-PKG 0.249

0.203 (g I M2 day)

Table 6.3: WVTR Results of the Dryflex-C Stmcture

 

 

 

Lamination Source Result (9 I M2 day)
Dryflex-C MSU-PKG 0.001
Dryflex-C MSU-PKG 0.001

 

 

0.001 (g r M2 day)

93

 

 

 

Table G.4: WVTR Results of the Nylon-A Structure

 

 

 

 

 

Lamination Source Result (g I M2 day)
Nylon-A MSU-PKG 0.235
Nylon-A MSU-PKG 0.152

0.194 (g r M2 day)

Table G.5: WVTR Results of the Nylon-B Structure

 

 

 

 

 

Lamination Source Result (g l M.2 day)
Nylon—B MSU—PKG 0.193
Nylon-B MSU-PKG 0.221

0.207 (g I M7 day)

Table G.6: WVTR Results of the Nylon-C Structure

 

 

 

 

Lamination Source Result (g I M2 day)
Nylon—C MSU-PKG 0.249
Nylon-C MSU-PKG 0.193

 

0.221 (g r M2 day)

 

 

 

Table 6.7: WVTR Results of the Tyvek® Structure

 

 

 

 

 

95

Lamination Source Result (9 l M2 day)
Tyvek® MSU—PKG 0.414
Tyvek® MSU-PKG 0.450

0.435 (g r M2 day)

 

REFERENCES

97

ASTM D 1709-85, “Impact Resistance of Polyethylene film by the Free-Falling
Dart Method", Selected ASTM Standards on Packaging, American Society of

testing and Materials, ASTM, Third Edition, 1989.

ASTM D 1876-95, 'Standard Test Method for Peel Resistance of Adhesives (T-
peel test)", Selected ASTM Standards on Packaging, American Society of testing
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ASTM D 4169-93, ‘Standard Practice for Performance Testing of Shipping
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Society of testing and Materials, ASTM, Third Edition, 1989.

ASTM D 4332-89, "Standard Practice for Conditioning Containers, Packages,
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American Society of testing and Materials, ASTM, Third Edition, 1989.

ASTM F 1249-90, ‘Water Vapor Transmission Rate Through Plastic Film and
Sheeting Using a Modulated Infrared Sensor", Selected ASTM Standards on
Packaging, American Society of testing and Materials, ASTM, Third Edition,

1989.

98

 

Bikerrnan, J.J., “Science of Adhesive Joints,” Adhesion and Cohesion. No.1.
New Yorlc American Elsevier Publishing Company, Inc; 1962. Pp. 36-45.

Briston, J. H., Plastic Films. No. 3. England: Longman Scientific & Technical

in Association with the Plastics and Rubber Institute; 1989.

Bruins, F. P., “Plastic Film Vs Paper in Packaging, " Packaging with Plastics. New
York: Gordon and Breach Science Publishers, Inc., 1974. Pp. 73-83.

Deanin, R. D., “Adhesives, " Polymer Structures, Properties and Applications.

Massachusetts: Cahners Publishing Company, Inc., 1972. Pp. 407-408.

DuPont, 1997; www.dupont.comltyvekl

Monsanto, 1997; www.monsanto.comlsaflexl

Osborn, Kenton R. and Wilmer A. Jenkins, Plastic Film Technology and

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1 992.

99

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