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"‘f'lf’vv ~-. m H .2 ,‘~,_‘ Wfiflugswm A. . _ 35:1. . ’ ”v.39 94:1:- ., ~ "v r 9: \ \llllllll \\\\\\\\\\\\\\\\\\\\\l\\\\\l\\ ll WWI L 3 1293 m I This is to certify that the thesis entitled THE PHOTO-OXIDATIVE DEGRADATION OF WOVEN POLYPROPYLENE: CORRELATING OUTDOOR WEATHERING, SUNSHINE CARBON ARC TESTING AND FLUORESCENT ULTRA-VIOLET CONDENSATION TESTING presented by Jessie Lorraine Layfield has been accepted towards fulfillment of the requirements for Master degree in Packaging IL“, ref/4 Major professor Date 55/ / 9/ 51 V 0-7639 MS U is an Affirmative Action/Equal Opportunity Institution LIBRARY Mlchigan State University PLACE ll RETURN BOXto movable mutton! your record. TO AVOID FINES Mum on or baton duo duo. DATE DUE DATE DUE DATE DUE / ~ ' 3. ft 8,3,} :9 ‘ 19% MSU loAn Nam-five ActlonlEmal Opportunly [m W1 THE PHOTO-OXIDATIVE DEGRADATION OF WOVEN POLYPROPYLENE: CORRELATING OUTDOOR WEATHERING, SUNSHINE CARBON ARC TESTING AND FLUORESCENT ULTRA-VIOLET CONDENSATION TESTING BY Jessie Lorraine Layfield A THESIS Submitted to Michigan State University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE School of Packaging ‘ 1994 ABSTRACT THE PHOTO-OXIDATIVE DEGRADATION OF WOVEN POLYPROPYLENE: CORRELATING OUTDOOR WEATHERING, SUNSHINE CARBON ARC TESTING, AND FLUORESCENT ULTRA-VIOLET CONDENSATION TESTING BY Jessie Lorraine Layfield Three woven polypropylene fabrics differing in proprietary additives were donated by various bag manufacturers. Replicates of each fabric were exposed to outdoor weathering in Florida, Sunshine Carbon Arc testing and fluorescent ultra-violet condensation testing. The results of the accelerated tests were compared to the results of the outdoor test and of each fabric was compared to one another. The exposed fabrics were initially examined for physical degradation and then tested for a decrease in tensile strength. The tensile strength for all three fabrics, after being exposed to the various test methods, decreased. Generally, as the exposure time increased so did the amount of degradation. The results from the three test methods concluded that fabric 8 had the largest average tensile strength decrease. Correlation between test methods was determined using linear regression. The results show that the best correlation was obtained between carbon arc and outdoor test methods. Dedicated to my loving parents Dudley and Shirley Layfleld. ACKNOWLEDGMENTS Dr. Susan Selke: thanks for your guidance, technical support, advice and patience. Most importantly, thanks for believing in me. Dr. Diana Twede: thanks for your guidance, support and friendship. Dr. Charles Petty: thanks for providing your technical expertise and guidance while serving on my committee. Damon Layfield and Michelle Snyder, thanks for all your help. A special thanks to Dr. John Howard Jr. and Dr. Aurles Wiggins. Thanks to United States Department of Agriculture, Textile Bag Manufacturers Association, and the Q-Panel Company for providing equipment and financial assistance. A special thanks to Michigan State University, Dr. Jay, Frito Lay and the Urban League for sponsoring minority programs and scholarships. iv TABLE OF CONTENTS List of Tables ............................................. vii List of Figures ............................................. viii Nomenclature and Units ..................................... xii Introduction ............................................... 1 The Objectives of this study ............................... 3 Literature Review ............................................ 4 Photo-Oxidative Degradation Mechanism ...................... 5 Activation Spectrum ..................................... 7 Additives ............................................ 11 Test Methods ........................................ 13 Correlation .......................................... 16 Materials & Methods ........................................ 18 Outdoor Testing ...................................... 18 QUV Testing ............................. ‘ ............ 19 Sunshine Carbon Arc Accelerated Testing .................... 23 Instron Testing ....................................... 23 Results&Discussion............... ......................... 26 Carbon Arc Exposed Samples ............................ 26 V Outdoor Exposed Samples ............................... 28 OUV Exposed Samples ................................. 30 Correlation .......................................... 46 Carbon Arc Exposed Samples ....................... 46 Outdoor Exposed Samples .......................... 48 OUV Exposed Samples ............................ 48 Discussion ...................................... 49 Summary & Conclusions ..................................... 74 Recommendations ..................................... 76 Appendix ................................................ 77 List of References ......................................... . 123 1O 11 12 13 14 LIST OF TABLES Carbon Arc Exposed Averages ............................ 27 Outdoor Exposed Averages .............................. 29 QUV Exposed Averages ................................. 45 Load as a Function of X (time) ............................ 47 Not Exposed Averages ................................. 78 Not Exposed ......................................... 79 Carbon Arc Exposed ................................... 80 Outdoor Exposed (1 month) .............................. 90 Outdoor Exposed (2 month) .............................. 92 Outdoor Exposed (3 month) .............................. 94 Outdoor Exposed (4 month) .............................. 96 Outdoor Exposed (5 month) .............................. 98 OUV Exposed ....................................... 105 96 Elongation as Function of x (time) ....................... 116 vii 1O 11 12 13 14 15 16 17 LIST OF FIGURES Norrish Type I & ll Reactions .............................. 8 Oxidative Photodegradation of Polypropylene ................... 9 OUV Weather-ometer ................................... 20 Inside OUV .......................................... 21 OUV Sample Holders ................................... 22 Sunshine Carbon Arc Apparatus ........................... 24 100 Hour Samples, OUV Exposed ......................... 31 200 Hour Samples, OUV Exposed ......................... 32 250 Hour Samples, OUV Exposed ......................... 33 300 Hour Samples, OUV Exposed ......................... 34 350 Hour Samples, OUV Exposed ......................... 35 400 Hour Samples, QUV Exposed ......................... 36 450 Hour Samples, OUV Exposed ......................... 37 500 Hour Samples, OUV Exposed ......................... 38 550 Hour Samples, OUV Exposed ......................... 39 600 Hour Samples, OUV Exposed ......................... 40 700 Hour Samples, OUV Exposed ......................... 41 viii 18 19 21 22 23 24 25 26 27 28 29 37 800 Hour Samples, QUV Exposed ......................... 42 900 Hour Samples, OUV Exposed ......................... 43 1000 Hour Samples, OUV Exposed ......................... 44 Carbon Arc Exposed, Load Vs. Time, Sample A (warp) .......... 50 Carbon Arc Exposed, Load Vs. Time, Sample 8 (warp) .......... 51 Carbon Arc Exposed, Load Vs. Time, Sample C (warp) .......... 52 Carbon Arc Exposed, Load Vs. Time, Sample A (fill) ............. 53 Carbon Arc Exposed, Load Vs. Time, Sample 8 (fill) ............ 54 Carbon Arc Exposed, Load Vs. Time, Sample C (fill) ............ 55 Outdoor Exposed, Load Vs. Time, Sample A (warp) ............. 56 Outdoor Exposed, Load Vs. Time, Sample 8 (warp) ............. 57 Outdoor Exposed, Load Vs. Time, Sample C (warp) ............. 58 Outdoor Exposed, Load Vs. Time, Sample A (fill) ............... 59 Outdoor Exposed, Load Vs. Time, Sample 8 (fill) ............... 60 Outdoor Exposed, Load Vs. Time, Sample C (fill) ............... 61 QUV Exposed, Load Vs. Time, Sample A (warp) ............... 62 OUV Exposed, Load Vs. Time, Sample 8 (warp) ............... 63 OUV Exposed, Load Vs. Time, Sample C (warp) ............... 64 QUV Exposed, Load Vs. Time Sample A (fill) .................. 65 OUV Exposed, Load Vs. Time Sample 8 (fill) .................. 66 ix 8 41 49 51 g 55 57 88% OUV Exposed, Load Vs. Time Sample C (fill) .................. 67 Carbon Arc & Outdoor (warp) ............................. 68 Carbon Arc & OUV (warp) ............................... 69 Outdoor & OUV (warp) ................................. 70 Carbon Arc & Outdoor (fill) ............................... 71 Carbon Arc & ouv (fill) ................................. 72 Outdoor & ouv (fill) .................................... 73 Carbon Arc Exposed, Extension Vs. Time, Sample A (warp) ....... 84 Carbon Arc Exposed, Extension Vs. Time, Sample 8 (warp) ....... 85 Carbon Arc Exposed, Extension Vs. Time, Sample C (warp) ....... 86 Carbon Arc Exposed, Extension Vs. Time, Sample A (fill) ......... 87 Carbon Arc Exposed, Extension Vs. Time, Sample 8 (fill) ......... 88 Carbon Arc Exposed, Extension Vs. Time, Sample C (fill) ......... 89 Outdoor Exposed, Extension Vs. Time, Sample A (warp) ......... 99 Outdoor Exposed, Extension Vs. Time, Sample 8 (warp) ........ 100 Outdoor Exposed, Extension Vs. Time, Sample C (warp) ........ 101 Outdoor Exposed, Extension Vs. Time, Sample A (fill) ........... 102 Outdoor Exposed, Extension Vs. Time, Sample 8 (fill) .......... 103 Outdoor Exposed, Extension Vs. Time, Sample C (fill) .......... 104 QUV Exposed, Extension Vs. Time, Sample A (fill) ............. 110 OUV Exposed, Extension Vs. ‘lime, Sample 8 (fill) ............. 111 OUV Exposed, Extension Vs. Time, Sample C (fill) ............. 112 61 62 83 65 67 OUV Exposed, Extension Vs. Time Sample A (warp) .. .......... 113 OUV Exposed, Extension Vs. Time Sample 8 (warp) ........... 114 OUV Exposed, Extension Vs. Time Sample C (warp) ........... 115 Carbon Arc & OUV (warp) - 96 Elongation ................... 117 Carbon Arc & Outdoor (warp) - 96 Elongation ................ 118 Outdoor & OUV (warp) - 96 Elongation ..................... 119 Carbon Arc & OUV (fill) - 96 Elongation ..................... 120 Outdoor & OUV (fill) - 96 Elongation ....................... 121 Outdoor & Carbon Arc (fill) - 96 Elongation ................... 122 Fill Carbon Arc Samples Degrees C Degrees F Extn Load Outdoor Samples 96 Elongation 96 Reduction UV OUV Samples RH Warp NOMENCLATURE and UNITS Yarn that is carried by the shuttle in weaving and "fills" in the fabric perpendicular to the warp yarns. Represented in hours Degrees Celsius Degrees Fahrenheit Extension finches) Represented in pounds Represented in months Change in length/gage length Percent reduction, ((initial load - final load)/initial load) x 100 Ultraviolet Represented in hours Relative Humidity Yam that is first threaded onto the loom. xii INTRODUCTION The United States Department of Agriculture (USDA) is the largest food buyer in the world. Commodities purchased range from vegetable oil to grain and infant formula. The USDA has the largest on-going food assistance program the world has ever known, with approximately 70 million recipients overseas. Food products are donated to countries around the world including Mozambique, Peru, Croatia and India. Here in the United States, approximately 1 in 7 Americans receive food assistance (Miteff, 1993). Multi-wall natural kraft bags, high density polyethylene bottles, tin plated steel cans and woven polypropylene bags are all containers used by the USDA to package products being Shipped overseas. The products are transported overseas by large steamships owned by various steamship companies. Once the products reach their destination port, the products are usually stored in a warehouse or storage facility, but sometimes they are stored on the docks or in open areas for long periods of time. Michigan State University (MSU) has been providing the USDA with packaging assistance for more than 15 years. MSU works for continual improvement in packages, develops performance standards, evaluates proposed packages and solves packaging related problems. This research was 1 2 requested by the USDA and the Textile Bag Manufacturers Association. This study focuses on the degradation involved when storing woven polypropylene bags outdoors for long periods of time in hot climates. The USDA currently buys between 40-60 million woven polypropylene bags per year, so this problem is of major significance (Miteff, 1993). Woven polypropylene bags stored outside are often exposed to ultraviolet radiation from the sun, atmospheric contaminants, and water from rain and the ocean. A combination of these variables and others often lead to the photo-oxidative degradation of woven polypropylene. Presently, the USDA uses the Sunshine Carbon Arc as its standard test method for bag manufacturers to use when testing woven polypropylene bags. The Sunshine Carbon Arc is an accelerated weathering test used to simulate outdoor conditions in hot and humid climates. The USDA standard when using the Sunshine Carbon Arc test is a minimum of 7096 load strength retention after 200 hours of exposure. However, the USDA is now considering allowing an alternative test method (fluorescent ultra-violet condensation type exposure test- QUV) for bag manufacturers to use. In this study woven polypropylene samples were exposed in the Sunshine Carbon Arc and OUV Weather-ometer and in actual outdoor tests conditions in Maimi, Florida. The exposed samples were visually examined for degradation and then tested for a decrease in tensile strength using an Instron tensile testing apparatus. The objectives of thls study are: 1 Compare the degree of degradation between fabrics. 2 Compare the degree of degradation between test methods. 3 Determine the correlation between test methods. The study first reviews the literature pertaining to photo-oxidation degradation, ultraviolet rays, activation spectrums, accelerated testing, outdoor testing and correlation of outdoor test methods. ‘lhe second chapter discusses the materials and methods used, followed by the results and discussion. The study concludes with a summary, followed by an appendix containing various data tables. LITERATURE REVIEW Photo, chemical, thermal, oxidation, bio and mechanical are some of the types of degradation that can affect polymers. For the purpose of this study we will be focusing on photo-oxidative degradation (weathering) of polypropylene. Photodegradation is the degradation of a polymer caused by exposure to ultraviolet radiation and/or other extreme sources of light (Encyclopedia, 1984). Oxidative degradation is the degradation caused by the reaction oxygen and ozone with a polymer structure (Encyclopedia, 1984). It is common to have one type of degradation initiate another type of degradation, or they may occur simultaneously. Degradation can be the loss of desired properties and/or the destruction of the molecular structure of the polymer. According to Hardy (1983b), polypropylene degrades through a radical chain process. In 1984, Hawkins concluded that the photo-oxidative degradation mechanism occurring in polyolefins can be Norrish Type I or Norrish Type II. Contaminants, additives, pollutants, photostabilizers, temperature, light source, and the season of year, can all influence degradation. To measure and analyze the effect of photo- oxidative degradation, several tests methods are available. Ultraviolet light (290-400nm), visible light (400-760nm) and infrared light (above 760nm), combine to form the electromagnetic energy from sunlight. The major factor responsible for photo-oxidative degradation is ultraviolet radiation. Wavelengths in the ultraviolet region vary in their effectiveness in causing degradation. Generally, the shorter ultraviolet wavelengths tend to cause more degradation. This is largely because of their higher energies and greater tendency for being absorbed by materials (Searle, 1984). Ultraviolet radiation is largely responsible for the generation of free radicals, while it has little to no effect on the propagation steps of the reaction (Grassie, 1985). "When polymers are exposed to sunlight, bond cleavage and destructive oxidation occur, leading to reduction in molecular weight and consequently a diminished service life for the polymer“ (Hardy, 1983a). Mchgue and Blumberg (1967) investigated the factors affecting light resistance of polypropylene, concluding that the photo-oxidative degradation of polypropylene proceeds from the exposed surface inward. This leads to the conclusion that thicker samples may not degrade as rapidly as thinner samples. Morphology of a polymer may also impact degradation. Oxygen permeates readily through the amorphous regions of polypropylene, however not as readily through the crystalline regions (Grassie, 1985). Thus one can expect that a more crystalline polymer will not degrade as readily as an amorphous polymer. This assumption does not hold true for all cases, because 6 a small amount of oxygen permeation can cause considerable degradation of crystalline structures. Oxygen can penetrate into the amorphous region and weaken the ’adhesives' that hold together the crystalline region, sometimes causing as much degradation as if the structure were not crystalline (Grassie, 1985). Ultraviolet radiation can be absorbed into polymers through groups in their normal structure, but quite often it is the presence of structural irregularities or associated impurities that are primary ultraviolet absorbers (Hawkins, 1984). "Polypropylene’s aliphatic structure suggests it should not absorb ultraviolet light, the presence of impurities can cause enough absorption to initiate degradation“ (Hardy, 1983a). Polyethylene, polyvinyl chloride, and polystyrene are all more resistant to photo-oxidative degradation than unstabilized polypropylene (Seppala et al, 1991). Degradation generally begins at the weakest available bond. Unsaturated bonds (double bonds) tend to enhance degradation of a polymer. Chromophores in polymers cause degradation by readily absorbing energy so that it can be available for cleaving bonds. Chromophores tend to absorb only at certain wavelengths. Hydroperoxide groups, aromatic compounds and ketones are examples of Chromophores. The energy content of absorbed ultraviolet light can be sufficient to rupture carbon-carbon, carbon-oxygen and carbon-hydrogen bonds near the surface of polymers“ (Tobin and Vigeant, 1931). 7 Some uncertainty surrounds the initial reaction in photo-oxidation. Guillet, suggests hydroperoxide or carbonyl groups are responsible for initiation of degradation, while Carlson and Vlfiles, emphasize the role of hydroperoxides (Hawkins, 1984). More research is needed to be conclusive. As stated earlier, Norrish Type I and Norrish Type II reactions are common mechanisms for photo-oxidation of polypropylene. The same mechanisms also can occur for the photo-oxidation of polyethylene (Hawkins, 1984). (See Figure 1.) The type I reaction involves the production of a free radical, which promotes chain scission and thus further reaction of free radicals. The Norrish Type II reaction does not directly produce free radicals; however, it does directly produce main-chain cleavage, and thus a decreased molecular weight. Cross-linking can take place in both types of reactions. In 1970, Cicchetti proposed a mechanism for the photo-oxidative degradation of polypropylene. (See Figure 2.) mm An activation spectrum identifies in a polymer the wavelengths that are most damaging to that material (Searle, 1986). The spectrographic and filter techniques are two techniques used to obtain an activation spectrum. With the spectrographic technique, individual regions of the spectrum are isolated and Norrish Type I: O — -— —CH,—CH,—C—CH,—CH,— — — o L — — —CH,—CH,C° + 'CHz—CHz— — —. 1 — — —CH,—CH3 + co N 'hT Il: orns ype O — — {Hz—CHz—{—CH2_CHz—CH2— _ — O I L — — —CH,—CH,—C—CH, — CH,=CH—CH,— — —- Fig. 1: Norrish Type I & ll Reactions (Hawkins, 1984) lst Phase (initiation) \ /-/ \ / \ c [cu—cu ur— \mfi‘ cln, cu, cu, type II cleavage at '(n. n’) singlet (III, 0 CH, \ / / \ C + CII-CII Cll- \ / l. I, CH, CH LII, LII, (ill, (acetone) (olefin) Ketone '(u, n‘) + '0, —l- kctone (5.) + '0, II II,C (ill, I'III,C C”, | l/ \ / \ )LF—C CII- C—I’.‘ CII— / I I —-> / I. (ll! (H CH, CII II LII, / \ / \ / (in. o o Cll, 0—0 20d Phase (degradation) Cll, ('TII, ('le. ('le. CH. CH, . . h l —('_A-Cll,-('.-Cll,-C'-CI!,- —> "0' + —C-CtI,—C-CII,—2fi-CII,~ l u o If I‘ve0 u L.) 1'1 j radical) 0 l I It (t-Iiydropcroxidc) (in' (EH' C”. -C-—CII; + C-Cler-CI l,— I I . I It 0 II (free radical) , (0 . RII Free radicals —:-——,> t-hydroperoxides Fig. 2: Oxidative Photodegradation of Polypropylene (Cicchetti, 1970) 10 are incident on adjacent areas of the same sample (Searle, 1984). A plot of the measured degradation versus wavelength of irradiation is used to obtain an activation spectrum (Searle, 1986). The filter technique uses a separate sample for the radiation transmitted by each filter (Searle, 1984). “In contrast to the spectrographic technique, the filter technique provides a larger size sample which allows physical property as well as optical measurements of degradation to be made“ (Searle, 1986). There are four main factors that are used in determining an activation spectra: 1) emission characteristics of the radiation source: energy and intensity; 2) absorption properties of material: characteristic absorption, effect of thickness, and effect of impurities; 3) criteria of degradation; and 4) stability of the polymer to absorbed radiation (Searle, 1986). It is important to note that each activation spectrum is based on measurement of a specific type of degradation. Therefore, activation spectrums may vary. Activation spectrums can be useful in selecting ultraviolet screeners and absorbers. “Since the effectiveness of an ultraviolet absorber depends on its ability to screen the actinic wavelengths from the polymer, the relative ‘ effectiveness of several absorbers can be estimated from the match of their spectral characteristics to the activation spectrum“ (Searle, 1986). Activation spectrums can also be useful when selecting which accelerated weathering test tO USO. 1 1 Am Some of the uses of degradable polymers include stretch tape, rope, food bags, seed bags, artificial turf, and beverage ring connectors. A major concern when using degradable plastics is their susceptibility to premature failure when exposed to sunlight. The effects of photoooxidative degradation include both physical and mechanical property loss. Physical property losses include yellowing, discoloration, chalking, brittleness, and flaking. Mechanical property losses include a decrease in impact strength, tensile strength and elongation at break. The combination of physical and mechanical property losses lead to a less desirable and a less reliable polymer. There has been considerable research in this area directed toward making polymers more stable when exposed to sunlight, stabilizing or reducing the rate of reaction of the polymer. Premature failure of polymers used in outdoor applications can be prevented by using a photostabilizer and/or an antioxidant. There are five general types of photostabilizers: (1) ultraviolet screeners, (2) ultraviolet absorbers, (3) excited state quenchers, (4) hydroperoxide decomposers, and (5) free radical scavengers (Hardy, 1983a). Ultraviolet screeners can be opaque additives or pigments which reflect or absorb ultraviolet radiation before it penetrates into the interior of the material (Kelen, 1983). However, screeners sometimes have adverse effects on other additives (Kelen, 1983). Carbon black, zinc oxide, titanium dioxide and iron 12 oxide are all commonly used as screeners (Hardy, 1983a). Ultraviolet absorbers absorb and dissipate the energy of ultraviolet radiation which has penetrated into the interior of the polymer (Kelen, 1983). Commonly used absorbers are 2-hydroxybenzophenones and hydroxyphenylbenzotriazoles (Hardy, 1983a). Ultraviolet absorbers perform well with thicker samples. 'Ouenchers relieve the excited polymer molecules of their excess energy, returning them to ground state; the excited quencher then releases its newly acquired energy as harmless heat“ (robin et al, 1981). Hydroperoxide decomposers destroy hydroperoxide groups before light absorption takes place (Hardy, 1983a). Nickel dibutyldithiocarbamate and nickel di-isopropyldithiophosphate are common hydroperoxide decomposers. Hindered amine light stabilizers (HALS) are free radical scavengers which terminate free radical photo-oxidation reactions (Tobin et al, 1981). “HALS are most effective in the stabilization of polymers which undergo a free-radical chain oxidation after photo-initiation“ (Carlsson et al, 1984). Quinones, aromatic amines and conjugated molecules are examples of scavengers. In addition to photostabilizers, antioxidants are sometimes needed to help impede degradation. 'The antioxidant may be a free-radical scavenger that interrupts the degradation or it may be a peroxide decomposer" (Tobin et al, 1981). BHT is an example of an antioxidant. When combining a photostabilizer and antioxidant, it is generally the goal to obtain a synergistic combination. 13 However, it is possible to obtain an antagonistic combination. For example, “carbon black can inhibit oxidation and also function as a light stabilizer; however, its combination with phenolic and amine compounds is disadvantageous because it catalyzes their oxidation" (Kelen, 1983). Photostabilizers and antioxidants last only until they are used up by chemical reactions. Using monomers of high purity and proper selection of processing to avoid initiator or catalyst residues are both additional ways to achieve polymer stabilization. MW Accelerated laboratory tests and outdoor exposure tests are both common methods used to measure and analyze photo-oxidative degradation. Accelerated tests were developed as an approach to better control exposure conditions and to permit continuous exposure to the radiation (Schweitzer, 1987). There are two main purposes of using accelerated indoor test methods: (1) the determination of relative photochemical stability and weather resistance of different materials, and (2) the prediction of the life expectancy of samples from relatively short-term exposure testing (Mchgue and Blumberg, 1967). There are four light sources commonly used to produce artificial sunshine: (1) carbon arc, (2) fluorescent lamps, (3) xenon arc, and (4) mercury arc (Hirt and Searle, 1967). The carbon arc weather-ometers have been used as the standard for laboratory weathering since 1933 (Q-Panel, 1988). Carbon 14 are light sources give a closer approximation to sunlight at the short wavelength and of the spectrum (Hirt and Searle, 1967). However, “carbon arc has very strong emission peaks in the ultraviolet region, which are not present in sunlight” (Hardy, 1983b). Fluorescent lamps are generally expected to have a harsher effect on clear plastics than either sunlight or the carbon arc (Hirt and Searle, 1967). “Xenon arc emissions bear the closest relationship to the solar spectrum in the ultraviolet region“ (Hirt and Searle , 1967). Preference is usually given to a xenon are light over carbon arc (Hardy, 1983b). 'There is probably as much short wavelength energy below 3200A in the mercury arcs as in the fluorescent sunlamp“ (Hirt and Searle, 1967). However,"in the longer wavelength region the background is weaker and the mercury emission lines are stronger than in the fluorescent sunlamp" (Hirt and Searle, 1967). The overall best light source to use depends largely on the test method and the purpose of the test. In general it is best to match the light source being used as closely as possible to actual sunlight (Fischer, 1984). Although this may lengthen the duration of test time, it will give more reliable results for most materials (Fischer, 1984). The are type of weather-ometers try to reproduce all of the sunlight spectrum, while fluorescent weather-ometers just reproduce the damaging effects (Brennan and Fedor, undated). UVA-340 fluorescent lamps may be best used to simulate the short wavelength portion of sunlight, while UV-B fluorescent lamps allow for faster testing (Brennan and Fedor, undated). As the 15 speed of a test is increased, the accuracy decreases, the reverse also holds true (Fischer, 1984). Xenon Arc lamps with quartz/borosilicate filters are often used in automotive tests. The Carbon Arc is best used when trying to determine the effect of the entire spectrum of sunlight on the polymer. Common instruments used in accelerated testing include weather- ometers, infrared spectrophotometers and Instron machines. The OUV, $3000 Xenon, UVCON and Sunshine Carbon Arc are all weather-ometers that provide an artificial light source for accelerated testing. Weather-ometers often have special features that range from condensation or spraying moisture on samples to simulate humidity, to having light and dark cycles to simulate day and night. Instron machines are used for performing tensile tests, thus measuring mechanical properties. The infrared spectrophotometers are used to measure carbonyl content. As photo-oxidation continues, the carbonyl group content increases (Hawkins, 1984). Degradation of polypropylene can easily be measured by its carbonyl content (Hardy, 1983a). Gel permeation chromatography can also be used in future tests to measure molecular weight distribution before and after exposure, thus analyzing and measuring degradation. Outdoor exposure involves photo-oxidation, thermal degradation and atmospheric contaminants. Thermal degradation is the effect of infrared radiation being absorbed into the polymer and ultraviolet radiation and is responsible for photo-oxidation (Hawkins, 1984). Atmospheric contaminants 16 (nitrogen oxides and sulfur dioxide) can actually increase the rate of reaction. Outdoor tests are usually conducted in either southern Florida, where material are exposed to sunlight and high humidity, or in Arizona, where materials are exposed to sunlight and low humidity. With an increase in temperature and humidity there is generally an increase in degradation. “Ideally, the exposure site selected should approximate the conditions to which the polymer will be subjected in the intended application“ (Schweitzer, 1987). Latitude, season, pollution and cloud cover are just some of the geographic influences that affect how much ultraviolet radiation reaches the earth. Variation in the level of ultraviolet radiation is also influenced by different ozone concentrations and the intensity of sky radiation (Hawkins, 1984). The summer months are the best time for outdoor testing, because of higher temperatures, increased ultraviolet intensity and longer days, thus more sunlight. The major problem with outdoor testing is the time required to obtain results. Nonetheless, outdoor testing is used extensively since it does reflect the actual conditions of use (Schweitzer, 1987). 9913131191! Correlation of accelerated weathering to outdoor testing is often complex and difficult. As stated earlier, there are many factors that influence photo- oxidative degradation outdoors; some are not reproduced in accelerated laboratory tests conditions, thus variation in results may occur. Sample 17 preparation and storage, test conditions and test equipment may all contribute to variation in results. In 1987, Simms investigated the variability between replicate samples and found that both accelerated and outdoor exposure results of duplicate samples were greatly variable (Fischer and Ketola, 1993). To adjust for variations, accelerated shift factors, statistical correlations, models and correlation coefficients have been developed. There are two types of statistics that are commonly used to measure correlation, Pearson’s r, which is a parametric measure, and Spearman’s Rho which is non-parametric“ (Crewdson, 1993). Pearson's linear correlation works under the assumption that the degradation can be measured on an interval scale (Grossman, 1977). However, Spearman’s rank correlation uses visual ranking like physical degradation or color loss (Grossman, 1977). To help reduce the need for the correlation coefficients, continuous monitoring and stringent controls of tests methods may be helpful. The best correlation method to use depends largely on the tests being conducted. According to Crewdson (1993), the best use for correlation results between outdoor and laboratory accelerated tests is as a guideline rather than a rule. MATERIALS Three woven polypropylene fabrics differing in proprietary additives were donated by bag manufacturers. These fabrics are typical of those used by the USDA. The resins are formulated by the manufacturers to have adequate UV stabilizers to meet the 200 hour carbon arc test. All three fabric are circular woven. Sample A had an average thickness of .01208 inches and had 10 (warp) by 11 (fill) yarns per inch. Sample 8 had an average thickness of .00924 inches and had 9 (warp) by 9 (fill) yarns per inch. Sample C had an average thickness of .00724 inches and had 11 (warp) by 7 (fill) yarns per inch. All three samples had a white color. Fabric weights: Sample A: 2.65 oz/yd2 Sample 8: 2.68 oz/yd2 Sample C: 2.38 oz/yd"E METHODS W The specimens were mounted on a plywood backing and exposed to direct weathering in south Florida at 45 degrees South, following ASTM-G7-89. The specimens were tested at 1, 2, 3, 4, and 5 months of exposure, beginning on 18 19 August 24, 1993. Outdoor weather conditions were recorded by South Florida Test Service in Miami, Florida. Sample size was 4" by 12". am The specimens were exposed in a OUV/SE Accelerated Weathering Tester, in accordance with ASTM 653. OUV/SE is manufactured by the Q-Panel Company, in Cleveland, Ohio. The specimens were tested for 100, 200, 250, 300, 350, 400, 450, 500, 550, 600, 700, 800, 900, and 1000 hours. The OUV machine was located in a temperature controlled (72 degrees F and 5096 RH) room. Samples were rotated every other day. (See Figures 3, 4 & 5.) Test conditions were as follows: Light Source: UVA-340, fluorescent bulbs Temperature: UV cycle 70 degrees C, Condensation cycle 40 degrees C lrradiance Level: 1.35 i .05 W/mz/nm @ 340nm Test Cycle: 8 hours UV/4 hours condensation Sample Size: 4.5" by 7.5' Water Type: Regular drinking water Fig.3 : QUV WEATHER-OMETER 21 Fig. 4: INSIDE QUV Fig. 5: OUV SAMPLE HOLDERS The specimens were exposed in a CXW #1 Sunshine Carbon Arc Weather- Ometer, in accordance with ASTM 5804. The specimens were tested at 100, 200, 300, and 400 hours intervals. (See Figure 6.) Test conditions were as follows: RH: 55 .t 5% Spray Nozzle: F-80 Black Panel Temperature: 63 i 2 degrees C Test cycle: 102 minutes light, 18 minutes dark and spray Filter Type: Corex D Sample Size: 2 5/8' by 8" Light Source: Sunshine Carbon Arc Water Type: Deionized Water W119 Nonexposed, conditioned (72 degrees F and 5096 RH) samples of all three fabrics, in both fill and warp direction, were tested using an Instron machine, in accordance with ASTM 05035 (ravel test). Once specimens were exposed to one of the three testing methods, they were tested for a decrease in tensile strength using the Instron machine. Exposed specimens too brittle to be 24 Fig. 6: SUNSHINE CARBON ARC APPARTUS 25 handled or having any visible hole through the sample were not tested in the Instron. Their tensile strength was considered to be zero. Testing conditions were as follows: Load Cell Weight: 5Kn Gage Length: 3" Speed: 12 in/sec Sample Size: 10 yarns Jaw Pressure: 90 psi RESULTS 8: DISCUSSION W Samples exposed in the Sunshine Carbon Arc Weather-ometer showed no signs of physical degradation, but they did show a decrease in load strength when tested using the Instron. (See Table 1.) Sample A showed an unexplained increase in load strength between 100 hour and 200 hour samples in both the warp and fill direction. In the fill direction there was some increase between 300 hour and 400 hour samples. Sample 8 in the warp direction showed some fluctuation (decrease then increase in strength) in the 200 hour and 300 hour samples. However, in the fill direction there was a steady decrease in load strength. Sample C showed a steady decrease in load strength in the warp direction. However, in the fill direction there was a little fluctuation between the 100 hour and 200 hour samples and between the 300 hour and 400 hour samples. Sample 8 showed the highest average percent reduction for load in the warp and fill direction, followed by Sample A and Sample C, respectively. 27 Table 1: Carbon Arc Exposed Averages -_ WAR-Pr ,1 FILU , 1% REDCT I 96_REDCT HOURS LOAD (EXTN jLOAD LOAD EEXTN : LOAD A l I 0; 106.24 0.7138i' 73.11 0.65157 100i 55.17 0.3141 48.07 44.51 3 0.3322 39.12 200 103.88 0.6412 2.22 65.55 L05443 10.35 300 96.35 0.6575 9.31 8.09 0.13981 - 88.93 400 64.04 . 0.3783 . 39.72 46.99 I 036891 35.73 IAvcz I 24.83 43.53 B l 0 96.55 0.7348 105.86 0.7756 100 79.59 0.6224 17.57 42.32 0.5326 60.02 200 60.70 0.4654 37.13 34.86 0.2270 67.07 300 76.16 0.5493 21.11 11.49 0.2136 89.15 400 67.03 0.4969 30.58 4.63 0.2050 95.63 AVG: 26.60 a 77.97 c 0 98.31 0.7384 80.46 0.6636 100 a 88.62 0.7267 9.86 71.08 0.6004 11.66 200 83.66 0.5352 14.90 78.55 0.5838 2.38 300 78.01 0.4986 20.65 59.20 0.4541 26.42 400 65.82 0.4440 33.05 63.26 0.4674 21 .37 AVG: 19.6131 AVG: 15.4587 28 W The only fabric to exhibit visible physical degradation after being exposed outdoors in Florida was Sample 8. In both the fill and warp direction, samples exposed for 5 months were extremely brittle. The samples actually broke apart when handled and therefore, were unable to be tested in the Instron. All three fabrics showed a decrease in load strength when tested in the Instron. (See Table 2.) Sample A showed a steady decrease in load strength in both the warp and fill direction. Sample 8 showed a very small initial increase in load strength, in both the warp and fill direction. This may be due to the brittleness that occurred. Some fluctuation between the 4 and 5 month . samples was shown in the warp direction for Sample 8. Sample C showed a consistent decrease in both the warp and fill direction. In the warp direction, Sample A had the highest average percent reduction for load, followed by Sample 8 and Sample C, respectively. However, in the fill direction Sample 8 had the highest average percent reduction for load followed by Sample A and Sample C, respectively. It is important to note however, that at 5 months Sample A was tested using the Instron, but Sample 8 was too brittle to be tested. Table 2: Outdoor Exposed Averages WARP 1 FILL I 1 . , L96 REDCT I93 REDCT MONTHS? LOAD I EXTN ILOAD LOADjEXTN LOAD A 1 L 106.24 0.7138 73.11 0.6515 81.06 0.5289 23.70 62.92 0.4619 13.94 73.58 0.4692T 30.74 51.52 0.3775 29.53 65.43 0.4191 38.41 45.00 0.3399 38.45 54.71 0.3589 48.51 37.71 0.3380 48.42 47.72 0.3225 55.08 32.68 0.2799 55.29 AVG: 39.29 37.12 0 96.55 0.7348 105.86 0.7756 1 97.26 0.6161 —0.74 107.30 0.6377 -1.36 2 79.36 0.4726 17.80 53.23 0.2440 49.72 3 57.17 0.4627 40.79 9.17 0.2824 91.34 4 62.75 0.4278 35.01 4.44 0.2529 95.80 5 0 0 100 0 0 100 AVG: 38.57 67.10 0 98.31 0.7384 80.46 0.6636 1 80.38 0.5101 18.24 64.29 0.5146 20.10 2 80.99 0.4801 17.62 62.20 0.4407 22.69 3 64.13 0.4147 34.76 56.21 0.4137 30.14 4 52.58 0.3581 46.51 45.13 0.3837 43.91 5 . 40.40 0.2699 58.90 37.45 0.3180 53.46 W All three samples showed some physical degradation at various time intervals. At 600 hours Sample A began to show the first signs of flaking and brittleness. (See Figures 7-16.) At 700 hours the brittleness increased and a visible hole was present. (See Figure 17.) At 800, 900 and 1000 hours the brittleness continued to increase and so did the size of the holes. (See Figures 18 - 20.) From 700 to 1000 hours Sample A was not tested an the Instron. Sample 8 began to show signs of flaking and brittleness at 300 hours. (See Figure 10.) At 350, 400 and 450 hours the flaking and brittleness increased to a point where the samples could not be tested using the Instron. (See Figures 11 - 13.) The first visible hole appeared at 500 hours. (See Figure 14.) The brittleness and hole size increased for the duration of the test times. (See Figures 15 - 20.) Sample C did not exhibit signs of flaking, but at 800 hours there was a noticeable amount of brittleness. (See Figure 18.) At 900 and 1000 hour test intervals the brittleness increased to a point where tensile testing was not possible. (See Figures 19 & 20.) No visible holes were ever present. All three samples showed a decrease in load strength when tested using the Instron. (See Table 3.) Sample A and 8 showed a steady decrease in load strength in both the warp and fill direction. Sample C had a slight increase between the 400 and 500 hour samples in the warp direction. There was a small fluctuation between the 550 and 600 hour samples in both the warp and 31 A(4 on left) B(4 in middle) C(4 on right) FILL Fig. 7: 100 HOUR SAMPLES, QUV EXPOSED A(4 on left) B(4 in middle) C(4 on right) FILL WARP ' Fig 8': 200 HOUR SAMPLES, QUV EXPOSED A(4 on left) B(4 in middle) C(4 on right) FILL WARP Fig. 9: 250 HOUR SAMPLES, OUV EXPOSED A(4 on left) B(4 in middle) C(4 on right) FILL WARP Fig. 10: 300 HOUR SAMPLES, OUV EXPOSED A(4 on left) B(4 in middle) C(4 on right) 5-... Wee—'1 1E7)?“ 7 ._ T . ‘ " h. 4 . amfi..:.~.¢:x' ‘ ‘1 FILL WARP Fig. 11: 350 HOUR SAMPLES, QUV EXPOSED A(4 on left) B(4 in middle) C(4 on right) Fig. 12: 400 HOUR SAMPLES, OUV EXPOSED 37 A(4 on left) B(4 in middle) C(4 on right) FILL WARP Fig. 13: 450 HOUR SAMPLES, QUV EXPOSED A(4 on left) B(4 in middle) C(4 on right) FILL WARP Fig. 14: 500 HOUR SAMPLES, QUV EXPOSED A(4 on left) B(4 in middle) C(4 on right) FILL ."I-I WARP ' , 9.“ HI Q --_ . n. V, Fig. 15: 550 HOUR SAMPLES, QUV EXPOSED A(4 on left) B(4 in middle) C(4 on right) FILL I: in WARP m'v III 111 II . _ - ~— .__, .- ve- - ,r Fig. 16: 600 HOUR SAMPLES, OUV EXPOSED 41 A(4 on left) B(4 in middle) C(4 on right) WARP Fig. 17: 700 HOUR SAMPLES, QUV EXPOSED FILL 42 A(4 on left) B(4 in middle) C(4 on right) Fig. 18: 800 HOUR SAMPLES, OUV EXPOSED A(4 on left) B(4 in middle) C(4 on right) FILL WARP Fig. 19: 900 HOUR SAMPLES, OUV EXPOSED A(4 on left) B(4 in middle) C(4 on right) Fig. 20: 1000 HOUR SAMPLES, OUV EXPOSED 45 Table 3: OW Exposed, Averages 4 WARP , ' FILL - : 9. 1892.1 - 850*: H414UPS 4 6660444412344 (.34 L0 “ 4 ‘“ LJHD an» L.1~__4 A g r , 0'; 106 24 0 7138; 3'1“"1 '8'651'4’54 ‘““_“' 100' 102 4'0 ;'“'0 61' 08 444 3.6 69 71 ' 0565:" ' 446434 442664 694. 6414: 0 6103 44 _1_6._2'2 3 44 67 64 4__644.,_4‘494__47_ 21 250.4 '98 0‘94“ “0 5185 15 20 61' 56:4 64252 _ _45414486 3007 64014 03330 39 75: 558 035107.219 444350 44646 63 40' 34340 444 44424 63 34-13___9519C1 ‘“ _ ‘436 82' ““4870 49 94' “.0 2982 44 _5299 44 564 46 2862444434995 450 44 14, o 2696 4444 _58 4454744424 149 _46 200544 _66 91 5004' 22 79? 0 1600 78 55 22 20 “'0 1945 “69 63‘I ”5‘50 12 94“; 01532 87.82? 8. 70 04.127 8810 600' 5.70:“ 0.2062 94.63 44 4.374“0.101'0“:““94 02 700; 0; oj 10013 07 0? 1004 8004 0: OT 1004 o? 0'14 100 900. 0 E“ o; 100“: of o: 100': 1000' 0} 0: 10041. 0 054 100 Ave: 63.58291“ . '- 6046893 B I i 3 o, 9655‘ 0.73448. 10566; 0.77564; 1004 96.30 0.6070, 0 264 102 90“ 0.66987 2.80 20074 8358 051151 13441 3291 0.2953: 68.91 2503 79.90 0.4290; 11.25, 12 45, 031934 88442444 300 45.64 0.2975; 52 731 12.67I 0.46534 88.04 350 0 03 1004 of 04 100 400 04 o. 1004 o, 0? 100 4505 0:4 oi; 1004? of 0! 1004 500 0; 0? 1004 o; 01' 100 550: 04 04 1004 0’: Of 100 600; 04“ OT 1004 014 0: 100 700 o? 045 1001; 0.? 0L 100 866 o ,i 0‘; 100; oi 0? 100 9004 0; o; 100“; 0: 0' 100: 1000;r 0 07 1004: 0 o: 100 I AW}: 4 77.40534; 5 89.1415 0 3 ‘ 49.22. 0 98.31 0.73844 8046 066364 100? 91 .664 0.6688 : 6.76 75.73 0.48207 5.88 200' 65.274 0.4203 33.61 63.34 , 0.4745 21 .28 250 68.703 0.4480 30.12 60.2444 0 4335' 25.13 300, 59.404T 0.3635 39.58 5377: 0.4713“: 33.17 3507““ 59.284 0 3293 39.70 51674 0 36904 36 53 400;? 41 .424 0 2845 57.87 45.93? 0 3658 _4444244 92 450': 51 _42: “ 0 3435 47.20 45 99 ' o 3053' 42 644 500‘; 32304 019334“ 67.14 38 03 031485 5273 550 :4 29 63‘ 0.20934 69 86 28 490' o 2455 54.084 6005 3311 0.1980: 66.325 33.81“ . 0.2700; 57.98 7004’: 1285-. 0.12401“ 8693,? 15.87? 0.1402. 80 28. 800: 2.84I 0.1213 97.114 2.83.? 0.1035: 9646‘ 900. 04 0, 1004 0'1 04 100 10004 04 0; 1004 01 o. 1004 i EAVGz 60.1939 IAVG= “ 54 2355 fill direction. Sample 8 had the highest average percent reduction for load in both the warp and fill direction, followed by Sample A and Sample C respectively. _QQBBELLTIQN. Correlation of the three test methods and three fabrics was obtained using linear regression. First, the load averages versus time (original graphs) were graphed using a best fit line. (Percent elongation was not used in determining correlation between test methods.) Secondly, from the original graphs the equation of a line (for each graph) was used and 50%, 60%, 70%, 80%, and 90% of the initial load strength was used as Y, and an X (time) was calculated. (See Table 4.) Thirdly, the X’s (time) calculated for each test method and each material were plotted against one another, again using a best fit line. Finally, from this last set of graphs X was set equal to 200 hours (USDA standard for carbon arc) and a Y (time) correlation was calculated for the QUV and outdoors. P AMP The load averages for the three carbon arc fabrics were plotted versus time (hours). In the warp direction: Sample C had a 97% correlation; Sample B had a 52% correlation; while Sample A had only a 8% correlation. 47 Table 4: Load as a Function of X (time) INrrIAL WARP LOAD A 105.24 B 95.55 C 98.31 FILL A 73.11 3 105.86 C 80.45 Y=LOAD OUTDOOR (MONTHS) B M A 98.585 -—10.851 8 108.98 47.385 C 97.309 -11.137 FILL B M A 70.797 4,1229 3 109.66 -25193 C 77.518 4,9577 QUV (HOURS) WARP A 104.97 —o.13051 3 79.076 —o.11045 C 93.094 —0.10566 FILL B M A 75.514 —o.09271 3 58.923 -0.08691 C 81.934 —o.08915 CARBON ARC (HOURS) 8 M A 93.78 —o.04322 B 88.5 —o.05247 C 98.002 —-o.o7559 FILL B M A 65.382 —0.08886 3 88.49 —0.23329 C 79.755 —o.04828 Y 0.5 53.12 48.275 49.155 36.555 52.93 40.23 WARP X 4.189936 3.491803 4.323786 X 4.21549 2.251369 4.685776 X 397.2876 278.8683 415.8527 X 420.238 68.95719 467.7434 WARP X 940.7682 643.9091 646.2098 X 325.141 143.8553 854.2567 Y 0.6 63.744 57.93 58.986 43.866 63.516 48.276 Y 0.7 74.368 67.585 68.817 51.177 74.102 56.322 Yr—MX‘FB X:(Y_B):7k1 X 3.210856 2.936439 3.441052 X 3.315442 1.831256 3.67468 X 315.8838 191.4531 322.809 X 341.3766 -52.8484 377.5011 X 694.956 489.3549 516.1529 X 242.6799 98.47829 680.4019 X 2.231776 2.381076 2.558319 X 2.415394 1.411144 2.663584 X 234.4801 104.038 229.7653 X 262.5152 ~174.654 287.2589 X 449.1439 334.8007 386.096 X 160.2188 53.10129 506.5471 0.8 84.992 77.24 78.648 58.488 84.688 64.368 X 1.252696 1.825712 1.675586 X 1.515346 0.991031 1.652488 X 153.0764 16.62291 136.7216 X 183.6539 —296.46 197.0166 X 203.3318 180.2465 256.0392 X 77.75773 7.724292 332.6923 0.9 95.616 86.895 88.479 65.799 95.274 72414 X 0.273615 1.270348 0.792853 X 0.615297 0.570918 0.641391 X 71.67267 -70.7922 43.67783 X 104.7925 -418.265 106.7743 X -42.4803 25.69233 125.9823 X —4.70336 ~37.6527 158.8375 43 (See figures 21 - 23.) In the fill direction: Sample B had a 84% correlation; Sample C had a 62% correlation; and Sample A had a 30% correlation. (See Figures 24-26.) W Graphs of load averages versus time (months) in the warp direction for the three outdoor samples showed: Sample C had a 96% correlation; Sample A had a 94% correlation; and Sample 8 had a 81% correlation. (See figures 27 - 29.) In the fill direction Sample A had a 98% correlation; Sample C had a 96% correlation; and Sample 8 had a correlation of 88%. (See Figures 30 - 32.) W Load averages for the three fabrics exposed in the QUV were plotted versus time (hours), using a best fit line. The graphs for the warp direction showed: Sample C had a correlation of 95%; Sample A had a correlation of 88%; and Sample B had a 61% correlation. (See Figures 33 - 35.) In the fill direction the graphs showed; Sample C had a 97% correlation; Sample A had a 87% correlation; and Sample B had a 48% correlation. (See figures 36 - 38.) 49 W In the warp direction correlation between carbon arc and outdoor test methods yielded 85% correlation; carbon arc and QUV yielded 80% correlation: and outdoor and QUV yielded 78% correlation. (See Figures 39-41.) In the fill direction correlation between carbon arc and outdoor yielded 31% correlation; carbon arc and QUV yielded 54% correlation; and outdoor and QUV yielded 59% correlation. (See FIgures 4244.) Since the warp direction gave the best correlation,it was used to calculate equivalent test times. Using the equation of the line from Figures 39 and 40 and the USDA standard: 200 hours (X) in the carbon arc was calculated to be equivalent to 1.65 months outdoors and 98.3 hours in the QUV. Using 98.3 hours in the QUV as X and the equation of the line from Figure 41, and equivalence of 1.54 months outdoors was calculated. LOAD (lb) CARBON ARc exposeo (warp) Load Vs. Time Sample A 120 , ' T‘" l‘. 100 ' II I -I 1.14-) so - ' 60 .I _ I 40 I 20 - y: 93.780 - 432209-21: RA2=0.082 0 v I ' I V r ' o 100 200 300 400 “NEW Fig.21: www.madwm SampIeA(warp) LOAD (lb) 51 CARBON ARC EXPOSED (warp) Load Vs. Time Sample 8 120 y = 88.500 - 824709-21: 8A2 = 0.520 100 d I 80 d A A ' A 60 - A 40 . 20 1 0 ‘ I ' I i I 1 0 100 200 300 400 TIME (hour) Fig.22: CarbonArc Exposed, Loast.Time, Sample 8 (warp) LOAD (lb) 52 CARBON ARC EXPOSED (warp) Load Vs. Time Sample C 120 100' y = 98.002 - 7.55906-2x RA2 = 0.974 I ' I ' I 100 200 300 1101: (hour) 400 Fig.23: CarbonArc Exposed. Loast.Time,SampleC(warp) LOAD (lb) CARBON ARC EXPOSED (fill) Load Vs. Time Sample A 120 1 y = 65.382 - 8.86600—2x RA2 = 0.309 100- a LOADA I ‘ I ' 200 300 400 TIME (hour) I 0 100 Fig.24: CarbonArcExposed,Loast.Time,SampleA(fill) LOAD (lb) CARBON ARC EXPOSED (fill) Load Vs. Time Sample 8 120 . y = 86.490 - 0.23329x RA2 = 0.846 ‘1 100 - A LOAD e I ‘ I ' I 100 200 300 400 TIME (hour) Fig.25: CarbonArc Exposed. Loast.Time,SampIeB(fill) t-Ih CARBON ARC EXPOSED (fill) Load Vs. Time Sample C 120 y = 79.785 - 4.6280e-2x #2 = 0.622 100 - . e LOADC E 80 - e v 7 C 2 4 o 60 ‘ ' _I . 40 -I I 20 u 0 1 I ' I ' I ' 0 100 200 300 400 TIME (hour) F1926: CarbonArcExposed.Loast.TIme.SampIeC(fill) LOAD (lb) OUTDOOR EXPOSED (warp) Load Vs. Time Sample A 1| y=98.585-10.851x m2=0.942 0 ' I ' I ' I 0 1 2 3 “ME (month) ss-I 0| fig. 27: Outdoor Exposed, Loast.Time, Stool-AMP) LOAD (lb) 57 OUTDOOR EXPOSED (warp) Load Vs. Time Sample B 120 ‘ y = 108.98 -17.385x m2 = 0.810 100 a) A 80 - 60 - 4o .1 20 .1 0 v I ' I ' I ' I 0 1 2 3 4 TIME (month) F1928: OutdoorExpoeed,Loast.Tlme,SempleB(werp) LOAD (lb) OUTDOOR EXPOSED (warp) Load Vs. Time Sample C 120 y: 97.309 - 11.137x RA2=0.968 100 ' . e LOADC 80 -I C ' m c- 40 -I 20 _. 0 I I ' I ' I ' ' ' O 1 2 3 4 5 TIME (month) Fig.29: OutdoorExposed,Loest.Tlme.SampleC(warp) LOAD (lb) OUTDOOR EXPOSED (fill) Load Vs. Time Sample A 120 y = 70.797 - 8.1229): HA2 = 0.960 100 5 I LOAD A 80 -I .I m .1 I 40 -I 20 4 q 0 I I ' l ' I r 0 1 2 3 4 5 TIME (moth) Fig.30: OutdoorExposed, Loast.Tine, SarrpleAdl) LOAD (lb) OUTDOOR EXPOSED (nu) Load Vs. Time Sample 8 120 j A y=109.66-25.198x RA2=0.883 100 - 1 A LOADB «l 80 -I w I 40 1 20 u q o 1 f TIME (month) F'Ig.31: OutdoorExpoeed,Loest.‘l'ime.SampieB(l) LOAD (lb) 61 OUTDOOR EXPOSED (nu) Load Vs. Time Sample C 120 * y = 77.518 - 7.95m RA2 = 0.962 100 . o LOADC 80 H o m -I o 40 u 20 q 0 r ' T r T ' ' ' 0 1 2 3 4 5 TIME (month) Fig.32: OutdoorExposed, Loest.Time.SampleC(lll) LOAD (lb) 62 OUV EXPOSED (warp) Load Vs. Time Sample A 120 y=104.97-0.13051x R42=0.882 100 - 1 LOADA 80 .. 60 u 40 .. 20a 0 . . . . . . . . . . 0 200 400 600 800 1000 TIME (hour) Fig. 33: OUV Exposed, Load Vs. Time, Sample A (warp) LOAD (lb) OUV EXPOSED (warp) Load Vs. Time SampleB 120 . y=79.076-0.11045x 842:0.618 1 d 00 .1 A A LOADB o 4.....¢;¢:¢4. 0 200 400 600 800 1000 TIME (hour) F1934: OUV Exposed, Loest. Time. Sample 6 (warp) LOAD (lb) OUV EXPOSED (warp) Load Vs. Time Sample C 120 . y = 93.094 - 0.10566x R42 = 0.954 OLOADC A f 0 ' ' r I ' T f fifi fi ' I f I t T T f 0 200 400 600 800 1000 TIME (hour) Fig.35: OUVExposed,Loast.TIme,SampleC(warp) LOAD (lb) 65 OUV EXPOSED (fill) Load Vs. Time Sample A 120 y -.- 75.514 - 927079-217 R42 = 0.877 100- E IJNHDA V U I U ‘ 600 800 1000 f U f 0 fl "W r ' V f V . 0 200 . 400 TIME (hour) F1936: OUVExposed,Loast.TimeSampleA(fll) LOAD (lb) OUV EXPOSED (fill) Loast.Time SampleB 120 ‘1 A y=58.923-8.69098-2x R42=0.483 100- . A LOADB 80.- 0 I 200 . .400. ' '600' '600r' V1000 TIME (hour) F1937: OUVExposed,Loast.TimeSampleB(fill) LOAD (lb) 67 OUV EXPOSED (fill) Load Vs. Time Sample C 120 . y = 81.934 - 8.9160e-2x R42 = 0.979 I Y ...,... ......,. 0 200 400 600 800 1000 TIME (hour) F19 38: OUV Exposed, Load Vs. TIme Sample C (ill) ‘5 OUTDOOR CARBON ABC 8: OUTDOOR (warp) TIME (load) y = 0.85496 + 4.0071 e-3x R"2 = 0.851 . . . . . fl . 4 r . . . . . 0 200 400 600 800 1000 CARBON ARC F1939: Carbon Arc & Outdoor (warp) OUV CARBON ARC & OUV (warp) TIME (load) 500 y = 2.7239 + 0.4781211 F142 = 0.808 a 400 - a 3 a 300 - a B 200 " 100 - ‘ 0 T I I T I ' ' T ' f T ' I 0 200 400 600 800 1000 CARBON ARC F1940: Carbon Arc & OW (warp) OUTDOOR 70 OUTDOOR a ouv (warp) TIME (load) y = 0.70581 + 8.48306—3X R"2 = 0.785 l ' I ' I 100 200 300 OUV Fig. 41: Outdoor 81 OUV (warp) , . 400 500 CARBON ARC 71 CARBON ARc & OUTDOOR (1111) TIME (load) 1000 y = 46.751 +118.91x R42 = 0.313 Flg. 42: Carbon Arc 81 Outdoor (fill) OUV. 72 CARBON ARc & ouv (fill) TIME (load) y = 138.16 + 0.38234): R42 = 0.544 100- 1 ' . . I . . I . , . 0 200 400 600 800 1000 CARBON ARC Hg. 43: Carbon Arc 81 OUV (fill) OUV OUTDOOR & OUV (fill) TIME (load) y = 53.669 + 89.847x R42 = 0.596 OUTDOOR Flg. 44: Outdoor 81 CW (fill) SUMMARY AND CONCLUSIONS There are numerous factors (internal and external) which can influence the rate Of photo-oxidative degradation many Of which were not taken into account during this study. Polypropylene degrades by a free-radical process, however the initial site for degradation is still ambiguous to researchers. To help retard or slow down the degradation ultraviolet absorbers, ultraviolet screeners, free radical scavengers and excited state quenchers are frequently added to materials. There are several techniques commonly used to measure degradation such as infrared spectrophotometer, Instron and weather-ometers. In this study the Instron was used to measure tensile strength, thus measuring degradation. Generally, the tensile strength should decrease as time increases (linear relationship). However, there was a small increase in tensile strength for some fabrics. This increase may be due to some initial brittleness that can occur in the fabric or due to crosslinking that can also occur. Chemistry and kinetics may also affect the rate Of degradation. Generally, the original correlations (load vs. time) showed good correlation between the test methods and fabrics. However, fabric A in the warp and fill directions had very poor correlation in the carbon arc test method. This poor correlation may have skewed overall results. Original correlations 74 75 were also calculated using extension vs. time. (See Appendix.) These correlations were generally good, however when graphed using percent elongation, correlation between test methods were very poor. (See Appendix.) Therefore, correlations using % elongation were not used. Overall, Sample B had the largest amount Of degradation an all three test methods) followed by A and C. Although the rate Of degradation varied between test methods, the order in which the fabrics degraded generally stayed the same. Data revels that sample B did not maintain 70% Of its initial load strength after 200 hours Of exposure in the Sunshine Carbon Arc. This study shows that there is a better correlation between the carbon arc and outdoor test methods than the OUV and outdoor test method. However, this does not imply that the OUV is not a viable test method, more research may be needed. The OUV is an appropriate quality control test, however stringent control of test conditions is needed. The OUV must be kept in a temperature controlled room and monitored closely. Samples must also be rotated consistently to assure even exposure. If adopted, the hours required for the test should fall in a range of approximately 98-200 hours in the OUV, until more research can be conducted. Data collected from samples exposed in the OUV show that all three fabrics maintained a minimum of 70% initial load strength after 200 hours Of exposure in the OUV. As stated earlier, 200 hours in the Sunshine Carbon Arc was calculated to be equivalent to 98.3 hours in the OUV. 76 W Further research may be needed to reinforce these findings. The following recommendations may be considered: 1. Modification of OUV test method may help to give a better correlation with outdoor testing (eg. lrradiance level or light source). Another fluorescent test apparatus (89 Atlas UVCON) should be compared. 2. Use gel permeation chromatography to determine composition Of fabrics. This may help tO better understand how the composition Of a material influences degradation. 3. Use Of infrared spectrophotometer to measure carbonyl content in fabrics. This could be used as a direct measure Of degradation. 4. Expand testing to include more time intervals and perhaps comparing different materials (eg. polyethylene & polypropylene). APPENDIX 78 Table 5: Not Exposed Averages WARP lFlLL LOAD EXTN ILOAD EXTN A 106.24 0.7138 73.11} 0.6515 B 96.55 0.7348 105.86) 0.7756 C 98.31 0.7384 80.46l 0.6636 Table 6: Not Exposed WAR—F5 (FILL F LOAD EXIN ,,,,,,, LLOAD _____ IEXTN _. A 117.30; 0.704 75.061 0.647 105.40 " 0.695 70.85? 0.7451 g 115.30 0.7621 77.18; 0.593; ' 114.10 0.737; 52.32? 0.579 109.20 0.704 7 79.46 0.640 85.64 0.657 85.42 0.660 101.30 0.759 65.21 0.550 104.20 0.755 80.11 0.703 100.20 0.698 77.29 0.637 109.80 0.667 68.24 0.766 AVG: 106.24 0.714 73.11 0.652 STD: 8.82 0.036 8.96 0.066 B 77.10 0.678 115.20 0.760 88.89 0.766 116.50 0.803 103.90 0.699 102.30 0.745 101.50 0.680 101.50 0.819 97.23 0.731 105.20 0.815 83.19 0.776 101.40 0.841 121.30 0.843 107.90 0.719 81.77 0.713 104.10 0.759; 108.20 0.761 88.40 0.777 102.40 0.701 116.10 0.718 AVG: 96.55 0.735 105.86 0.776 STD: 13.02 0.049 8.18 0.041 C 97.66 0.717 89.21 0.700 102.50 0.775 74.71 0.630 105.30 0.757 89.29 0.731 115.10 0.760 70.25 0.656 99.01 0.718 81.99 0.700 93.61 0.710 79.79 0.623 87.65 0.6171 86.31 0.648 104.70 0.7831 86.58 0.596 80.11 0.767 74.76 0.673 97.43 0.780 71.73 0.679 AVG: 98.31 0.738 80.46; 0.6644 3sz 9.26 0.048 6.89: 0.039 80 Table 7: Carbon Arc Exposed 2111741619 “___ FILL 2. ; _. 1099 9117 N 7 iii/77.93.211.77. .AMPLFHAH‘“ , __ ___2_22____ _2 1007176767 g 77 52 00 777770 30E 36.002 0.269 2 43 770 0 2249 2 $527,272 70747427 61. 02; _0_. 417 367.740; 0: 5: 7 7 .7. 7747. 76 0 254 7772772772972 2_ 121.2370 j 51.36} 0.266 46 34 0439 2 __2__87_.06: 0 2479 7_77_:_ 25727327 _7_7 0. 403 .: §§;9_9-_ 7:0 20_1-__..94.90 _ -9295. ,2 49 452; 0 283 50 34 0.336 --.- ‘ 97,-1.7 ‘ .0 979: - 99.92 .9997: .AV.3 =.....1 ...5.5.:_.1__7 ..0 3.14;-.- 7,519.51; __-_9-.3__933 STD: 14.87; 70 0_9_2 0.09; 0 077 _2_99_HRS 212 ___106 60 0.673;; 6757 727 9.99.7 105 70 0.655; 75 03 0. 530 2__ . 12027.40 929.71---.5139 ___ _0__ 483 I 199.20 _._9-994 9.219%. .79999 7. 17072230 __ __0897377 47. 60 , 0 474 111007717 0. 6581 92-231 9903 87. 84 0. 551 72.91 0 570 98 09 0. 563 70.44 L 0. 625 106. 80;.__ 026777 2321.575. 925.5. AVG: ; 10327. 88:77 0 7641 65255:i 9.539. STD = 71117 0.0821 8.73 I 0.062 300 HRS f 103.90 0.724; 11.89; 0.152 7" 98.42 0.705; 14.507; 0.197 2 91 95 1....-.9199. 49912 0.155 __97 29 0 6041 4.461 0.151 798 7673 7177777 707 58617.77 7777 757.725 7777 63:92: 98637! 06718 6.20; 0111 7777 85.7421 0. 58717 14.017: 0.161 967.54: 0 646:7 3.22 0.098 AVG = 1 96.73757 7 70765871 8.09 L 01407 STD: L 5.50, 0.0753 4.5917 0.036 8 1 Table 7 (cont’d) WARP 1 17FILL .__- LOAD é.Ex79.1.--1-.L089.-E_>QN_... 36111731715775: ? i " 400 HRS 7.1 68.321? 0457' 20.13; 0.2027 59951 9929...--.92193 -9399 53.53} 0.3575 56.837777 0.482 , 72.11: 035.191-91.194-.--4.s_1i4 61.401 0.331% 62.871 0.4973 70.74 6.7387677775737461 0737777 67361 0 373 39381 0.337 71.38 674402I 23.282'1 0.198 51.823 0.331" 60.08; 0483 AVG: 64.04 0.378 46.9917 0.3691 STD : 7.88 0.70749 ‘ 777715.77777777777071717Q SAMPLE B" 100 HRS 65.50 0.451 8.94 0.635 84.131 0.718; 4.51 0.276 88.132 0.6711 101.90 0.649 69.151 0.5371 79.922 1.355 80.56 7 0693‘ 93.291 0.521 102.60 0.752 4.97 0.068 67.03. 0.625; 2.74 0.224 AVG: 79.593: 0.622 42.32 0.5332 STD: 134717 0.104 46.67 0.424 200 HRS 49.56 0.3792 63.14 ' 0.329 36.97 0.3951 15.11 0.488 35.09 0.2791 31.52 0.158 47.87 0.472 12.51 0.092 73.77 0.5462: 37.74 0.160 44.19 1 0.56017 27.03 0.119 1 100.301 0.5861 19.89 0.0942 64.481 0.4261 71.92 0.376 76.131 0.4641 , 78.6? 0.547? 1 AVG: 1 60.70 0.465 34.86IL 0 22272 STD: 1 21.33 0.097 21.93 L 0.150 Table 7 (cont’d) 82 WARP EFILL _ -_-_...L.96_0_._.__-LEX_IN {— LOAD EXTN 93071267777 j -2- § 300 HRS 90.17;: 0.619: 12.59: 0.4g 67.64 j 0-._T63;4{ 1.93? 0.—085 97.61 0.697; 4.99? 0.203 77.61 T "65371 21.91T'T'fiéfij 109.403 0.625;r 32.007 048]. 76.52 0.586L 1.77j 0.141 60.30 0.5931 5.21' 0.327 47.03 0.326T 66.15 0546' 47.01 0.326 AVG: 76.16; 0.549 11.491 0.214 STD: 20.96} 0.125 11,53T: 0.136 400 HRS 75.66 0.5191 3.33 0.277 56.16 0.576T 5.40 0.347 63.76 0.450 3.36 0.313 66.65 0.607 5.21 0.275 67.11 0.535 6.91 0.096 99.92 0.535: 1.96 0.105 71.52 0.465’ 4.66 0.062 44.69 0.393 4.73 0.223 37.34 0.392 3.69 0.127 AVG: 67.03 0.497 4.63 0.205 STD: 19.621 0.076 1.94 0.103 SAMPLE G 100 HRS 91.44 0.737 41.77 0.259 72.59 0.7541 60.51 0.615 90.85 0.697 V 79.54 ~ 0.727 61.40 0.694 39.60 0.267 91.57 0.724 64.32 . 0.650 105.60 0.747 66.67 0.696 98.79 0.733 62.39J 0.591 76.44 0.759 81.15 g 0.670 86394” 0.695 4 63.577 0.707 AVG: 66.62 i 0.727; 71.06 0.600 STD: 10.16T 0.026} 16.60 0.195 Table 7 (cont'd) TWARP g 7F1LL >~ __.~ 14.- . _.- _ .. “-24 L940 66116116771111 TSN’PLE 5 __.- -. 200 HTRS 9 64. 64 T 0.597 61.50 T 0.655 ##TTTTTT T84 6'4 0 52 7'; 85.50 -' 0.574TT TTT—T—~_TTTTTT T 8327 7T—TTT0 51T T—T_90 5077 ‘TT—TTTTOTT6TT07T -i-;-7_T-::---Z”-j_82475:":2.540- - iii-1246 :jj-Qiis-z‘é 88.89: 0 569 __4_706; 0.5957 .‘— ___..- on .__.--- 64.99 0510 TT 76.75767 TTTTTO.563 60.66 2 0.520 61.34 g 0.534 ___—_._..___ _...___ 79.27; 0533 6244? "0.5667 1_--_---_.____,--__-§-3 92 7_ 0.7506 _____ _7_ __ 74:16: __7 63 66 6535: 76 55 76.564: STD: 2.73777 0030:1332 _7_7__0__.g_367 fl 4 T 4 P 300 HRS 7: 670. 32 0.4747 56.757: 0.427 80 81 0.5053 45. 40‘ 0.453 667.527 0.465} 65. 537 0 437 72.271 0.505? 65. 05 0 449 TTTTTTTTTTTT TTTT‘7T64T7T7T4T 05317 6666 6 4763 7.3 223 __ 3233-1- - ___--_-4..3 .73.---_---9_-§_34- 7511 0 455 61 53 770.420 84.77137 0487 60.621 0479 ..-._..~,_7.. _- _._.-. ___- -_24 " 61. 96 0 507 - 66.04 0.4467 47176: 1 76071 —T 04991 T77: 59.207 7770454 STD = 5. 56?— 70 6267‘ 6. 957T TTT0 626 ‘ l A ,7 . . ——v7- 0 f 1 I ‘ 1-_--_--_ 1 - 4.-- -+-- --__-- 400 HRS 71 77.96: 074776, 70.12. 0.490 ' 66. 23 -' 0 450? 64.24 7 0.523 .! 657.7557- _-__9-‘3TTT5-._--§2-44§ 0460 6177765 0 451 70.477 0.546 77 __7____ 62 07 0. 426 56.13 g 0.433 765 96 0462 66.527 0.451 ___F—m_ .....-c——.—. -... ‘_.__. 764 30 0 463 51.41 ; 0. 395 -----_-- .- _,----_ __- 62 763 0.365 64.76 04741 _ .fi ___..._._._.‘. T4943: 71; 65 62 1 0 444 63.26 0.467 STD: a 4 827 0031: 617' 0.046 EXTENSION (In) CARBON ARC EXPOSED (warp) Extension Vs. Time Sample A 0.8 7 l y = 0.60650 - 327009-41: R42 = 0.082 I EXTN A .1 a 0.6 - \ 0.4 - ' .1 a 0.2 - 0.0 . . . I . . . 0 1 00 200 300 400 TIIIE (hour) Hg.45:CarbonArcExposed,EnensionVs.Tm,Sm1pleA(warp) EXTENSION (In) 85 CARBON ARC EXPOSED (warp) Extension Vs. Time Sample B 08 1 y = 0.68354 - 5.489064): m2 = 0.647 AEXTNB 0.6 -' 1 A 0.4 - 0.2 - 0.0 V I ' r V l ' O 100 200 300 400 TIME (hour) Fig.46: CarbonArc Exposed, ExtehslonVs.Th1e, Sample 8 (warp) EXTENSION (In) Flo. 47: CARBON ARC EXPOSED (warp) Extension Vs. Time Sample C 0.8 ‘ y=0..75196-8.16900-4x RA2=0.910 o 5er c . 0.6 . 0.4 - 02 - . 0.0 . , . t . , 1 o 100 200 300 400 TIME (hour) Carbon Arc Exposed, Extension Vs. Time. Sample C (warp) axreuslou (In) 87 CARBON ARC EXPOSED (fill) Extension Vs. Time Sample A 0.8 y = 0.55886 - 7.5760e-4x m2 = 0.865 IEXTENSlONA 0.0 v I ' I ' I ' 0 100 200 300 400 “ME (hour) Fig.48: Carbon Arc Exposed, Extension Vs. TllTlO, Sample A (fill) CARBON ARC EXPOSED (fill) Extension Vs. Time Sample B 0.8 K * y = 0.68280 - 1.460268): R"2 = 0.817 A Samson B 0.6 - g t z 2 m 0.4 - 2 III .— X I“ 4 0.2 - J 0.0 . . . . . r . 0 100 200 800 400 TIME (hour) F5949: Carbon Arc Exposed, Extension Vs. Time, Sample B (fill) EXTENSION (In) CARBON ARC EXPOSED (flll) Extension Vs. Time Sample C 03 y = 0.66160 - 5.387004)! W2 2: 0.892 o EXTENSKN 0.6- C O 0.4 n d 0.2 - 000 V T V I f I V 0 100 200 300 400 “ME (hour) F1950: CarbonArcExposed,ExtensionVs.Thle,SampleC(llll) Table 8: Outdoor Exposed (1 month) WARP . F‘LL -. _‘_ LOAD _Exm L049 _ EXW ; '4: i:;__;-11z-55 _ 5 555 iii; 55 55 5 55. ‘ 7960 0464 6372 “£480; - L3 67.84LLQ.463:___~1816 _0_412J '4 55,- 52:;- 555 _5555- ,5 475 92 97M: 0 633 71 97 0. 557A _____--_-_-----_- i _ _64_._1_9_T_ __0 421 62 67 514-5-2- ___6940: 0 47 6 61 66 0.416 ____-_-._.--.--.- 55 53 _- 5 555 ' -1934 1W-5955 63 50:— 0. 340 ___32 76 _--_-_5_-5f‘§ L 69 99 ““0 626 67 06: 0.464 3 _-_- 61 95-_ 0 482:__ -- 67 33 _9-‘155 ‘: 69 T617“ 0 4171‘” 67 767"“ 0.426 77 37 1 0 549: 69.32 . 0.463 . 96 73 _.__-5:- 613'; 66 06: __0L433 T 66.30 1 9.5551. 66 9210407 . 159-491-2- 0559 ---55_33 2935.4. Aygz 61 C6 0 629'; 62 92 0 462 STD: 16.32 0 094 7 90 0.062 B ; .. ~—~i.:—— _ __L _ LJ 103.10 L0_._612L 126 2L 0 766 10960; 0 624 122 20:0 662 --_-_____.-.--__.-_-_1 5155:__-_5 5921-15150 . 5 557 1 103 00 0.611 113.00? 0.666 T 96. 751 0 640T 91.92 g 0.461 2; 555-57; - 0 5'82 --_1_15-50'. _ 9 7.46 1 96.319 0606: 8325: 0719 . 70.44T 066411111 60 5.5-5.5 1“ 72.06: 0 470 110 10 0.619 1 99615 0615 11020: 0.693 11619 _L_0 663 :L___96_81L __ __9. 660 11670L 0706 106 5’3... __9-5-7-4- 96 79:“ -_- 0 607L112 40’L 0 555 _-_--_-_._.-_ 6923: 0627i_ 11430 0666 109 00:” 0 662: “103.40. 6 606 -_. . 9697 ____ 0.669T 9600 __ 0629 9355: 1 9726: 0616 T107. 30 0633 970: 1293. 0.063 11 20 0.077 Table 6 (cont’d) 91 j WARP 1.05.5 :FILL 11:356- 4055 :96 6 5" 61:55::5551-::---5-1-23::5205‘ 66.09; 0.435 1_ 4735 ,1 0.453- 255-51; 5352......- 57.73; - 0.473 0.552; 1 64.00; 0642 T _.L 62.66; 0674 66-6; 4mm: 95.191 0.601 3 71.44; 67.927» 5587-? 0.555-1---55-55-429-5-29 74.31} 0.6391 67.303 0.630 1 5:57": 96.17: ___—_-__._.__. _ 0.640jw 67.44% 0.567 0.663; 67.277 0.4374 1 69.66% 0.623? 67.61§ 0.549 1 68.00: 0.409: 66.401 0.677 76.11; 0.467} 52.00; 0.496 69.16? 0.616? 70.983 0.647 76.70 ; 0.663; 58.25 0.360 93.61 T 06191 80.40 0.630” AVG :- 60.36} 0.620; 64.291 0.515 STD: 11.16? 0.0621 6.311 ~——-—-‘< 0.099 92 Table 9: Outdoor Exposed (2 month) .WAjR-F" F1 _1_ .- _ ELQAQ EXTN _LQAD EYTN A 1 7634 ' 0435 - 4555 “ 0357 _-_ T 7310: _ 0492 59 01 _ ‘6‘3‘65 F:. L ______57.49. 0 441 ‘7 _‘55. 47‘? -._ ‘6 421 1; 76.95% 6 4J0*414 36 6 334 55.25:___~ 0 556L 49. 95 6343 ‘ “ ‘ ‘7944_’:___ 6 46611.99 763:;9927 74.931“ 0539 5455 0414 55.45; 6 470L 56‘ 52 99.-399?. L 74.12; 0546 4123“ 0359 " 1 55.251 6 4251 54 69 6.376 7549 6 457 I 52 99 0.355 ‘ 80911 0435L 47191 0.329 L 71 .70L 6. 503L 53.53 a 0.355“ 55.15; 0.4551L______56L476_____g._39g 55.55 g 6 4352' 55.75: 6.355 75.571 6 450 . 52.59; 0.395 513: 73.55 0.459 g 51 .52} 0.375 STD: 4 7.371 0.047 L 5.50; 0.033 1 1 B 1 - 1 1 1 73.321: 0.459; 44.51 0.193 55.35} 0. 4137 55.79 0.249 . 101.20L 0. 5291 50.04; 0.2394 75.131 0 352 52.94L 0.235 * 51 .411 0. 3‘70L 43.33? 0.206 97.551 0. 550L 45.42 0.2st 5773‘} 0.572; 55.53 0.253 75.25 0 411 " 56.91 6.297 57.51:; 0. 355: 47.14; 0.241 97.55 L 0. 5271 5445‘; 0.253 92.05 0 5541 55.59 0.273 73.95; 0.419‘L 52.54; 0.243 57 54L 0 452‘ 54._93L____ 6255 L 56. 75‘? _.__. 0 423 54.93: 0.256: AVG: L 79 35 6. 473 ' 53.231 0.244“ 570: 1 14.24 1 6 653 5.35: 0.625 Table 9 (oont'd) 1WARP . “___ FiLL , ________ .-_.._ ___TLQAD _’_ TEXTN -. - LOAD EXTN __ 9w; as 91 _';_ _of :41 :i 8.? as :8 445. 82 58 8 411 - 88 27 8.472 88 48 _ 8 584; 88_. 78 _-_9-958 88 47 9 9.9.5: 88 87 8848 99.49 8 488 m _87_ .25; ..9.-_4_99 .i 83 87 8_._ 488 83 88 8.488 T 88 82T_______8_585 88. 97.1 _ _ ._924991 ‘ 55 82 8 488 87 18 8 447 75 4.9; “.9419 _._.__.49-89 _-__9;4.997 94 28 8 487 88 81 1 8 525 77 18: ; o 428T 58 _4_4 ___9439 88 88 ‘ 8 458T 74 58? 8 478 88 1.15....29449 “9144f;__9.-_999 87‘17T 8487T 85 88 8425 1 71 _253 9 4.29 .__ Z999. _.____9_-.5.99. AVG: ' 88 88 8 488; 82 201 8.441 STD: 18.25; 8 883 F 7.58 g 8.855 Table 10: Outdoor Exposed (3 month) LWAfi-fi 4 1. RH. _____ _______ " WW. _ ’LQAD _ LEE-'51.- 3' DAD E DWW - LA‘TT ’ T 78 82 -_ P 4181____ __45 21 L_:_O_§J7 _‘_“L ___ 5878 048 7 4_____812 _ 0.804 _T ”85.81 0 882“? 54 04: ___ 8 877 57.85 1 0 418 “777752 84 0 887 .__..W W 74 23; _. (1:133 4-- 3’5 43 __9350 1 77- 37 ' 0.457 4182. _._. 9:321. 58 88 0.401 ; 8718 0.888 W ._ A- -_94427L_.__-94493§W 41 2-3 _Ci; 3.321 1 71418; 0.4281 8888 0.828 , 5847? 0870; 8888 08241 __________ 1M” 81 881 0 448+ _ 49.19 0 817 f 58 15? 0 847T 58. 78 0:888 1 85.21 0.8781 52 727 0.8787 1 85.72 0.880 47.41 8887 1 8811 0401’ 45.10: 0808 Ave: 1 65.431 0.418 __ 45.00: 0.840 STD: g 8. 08 0 044T".- 8883 0.025 i4 1 t 1 i a 7" 1 57.853 0.885 8 871 0.718 1 85.22; 0.289L 10. 01 0.850 1 88.891 0 547 7 8.883 0.7887 1v____ 88.851 0 4711144524...- 8825 1 1 75.01 1 0 588 ! 7.08 1 049.73 T 88051 0.844 8.241; 0.508 42.28 0.487 8.28; 8.881 1 56.67; 0.551 885? 0.088 1 81.01 0 800 6.041 3094.. "78473 0. 250 10.74 0.070 38.28 0 285 9.881 04-19474 78.18 ; 0 488 8.87? 01414151 j 48.88 1‘ 0 4887111781 0185 - 8882 Q 845 8.54L 0.848 {1178: 1 57.171 0488' 8.17T 0.282 STD: * 22.871 0128 2.24? 0.240 Table 10 (cont’d) 95 WARP 1 jFlLL LOAD ___;EggfmwWLLOAD EXTN C 3 66.39] "0.71637" 61 .0547 0.459 64.38} 0.431 57.74 1 0.493 60.381 0.4753 49.56. 0.343 70.79; 0.464} 61.881 0.430 52.891 0.343} 56.13 0.358 46.95 0.302 ' 49.23.; 0.468 55.44 0.383% 54.36 0.357 65.48 0.419 62.74 0.368 71.33 0.491 60.43. 0.479 53.74 0.419 57.96 0.483 73.15 0.456 60.03 0.487 76.16 0.448 45.10 0.291 63.03 0.345 61.88 0.499 74.93 0.418 52.13 0.360 66.98 0.363 52.89 0.331 AVG: 64.13 0.415 56.21 0.414 STD: 8.76 0.056 5.45 0.071 Table 11: Outdoor Exposed (4 month) TWARP FILL 1 L040 TEXTN :LoAD EATN 2 4'“ T T 54 20 "T 6396 321.51:~ — 73.315 65 25 0 395? 38.12 0.2719 ___ _.__ __ 2.. 55.5.1. .22. .-- _0. 555; ___.5.0_~___25_5 229.2559. T_____ 6016 _.__.54553 3340 “10.3107 " 1 62317 6.3601 5’“ 34.93 ' 0333 ' 62.94? __0 3551 45 56 0.345 5 5251’ 0 4002 35 14 0.520: 4 56.891 0_ 391 29 37 0.291 T 48.671 6 321 {T— 37 69; 0.324 _ 59 46 ' 0.371 39.031 0 389 2.5555 -__..9-5225 392191 025523. 1 51921 0.3451 43391____0 421 . 37.85 . 0.2541 35.25 0.347 T 49._5_3_1 0.401T 41.231 0.302 E 57.69 0.336 35.601 0.335 45.915 0.320 41.101 0.327“1 54.93 0.407 49.321 0.344 5.5228 0.671 42.42 1 0222.9. 1 41.18' 0.246 . 36.97 0.303 70.17 0.401 33.721 0.377 five: 1 54 71 0.3591 37.711 0.338 STD: 7 60 0. 0491 5 051 0.057 B 60 637* *6. 426 1““"4481 0.307 44 5_4T 0 411 7.841 0.300 74.66 0.411 2.121 0.233 79.17 0.489 2.55 T 0.256 T 49.69 3 0.299 6.201 0.370 64.00 T 0443 3.171 0.278 74.34 0.4661 2.09: 0.297 26.70 0.510‘ 3.57 0194111 8.5341 0.457 2.17 0 190 59.281 0. 401 3.49 0.310 63.701 0_. 435‘ 9.241 0.162 60.081 0 431T 6.471 0.115 49.131 0.361T 2.121 0.237 65.661 0. 4451 6.421 0.145 55. _253 0.3441 1 1 61. 1010 456 1 TL 61. 53; 1 O 41L1 T 1 ‘ 73 21 0 5691 AVG: 62.751 0.428: 4.44 5 0.253 910: 14.471 0.0547 2.391 0.076 Table 11 (oont'd) 97 .WARP . F:1LL m L969"... 15fo 1 LOAD 7 7 EXTN ’C”"""'" " ‘" W 62. 82 0 3937 7 77747., 23 7777777673791 56 30 0 37 i; 53 53 0.36737 47 76 770 3591 7777777739 3377 7767371717 46 86 0 326 44 787' 0.396 1 437972.; 0 661 42 8777177777 07747097 52.891 0 320 46. 43 0. 366 717697.272; 0.3261 4737 52 7 77777643787 1 54 081 0.474 84 5010 249 7771 387 55 0.2527 41.69; 0.342 69.74 j 0.3962 37.531 0.445 45.45 7 0.396 5' 45.561 0.439 57.91 0.369 39.657 0.367 52.051 0.406 52.301 0.379 59.73 ; 0.414 54.66: 0.377 1 48.27 7: 0.35 36.4OT 0.349 44.56 0.280 .7 54.25? 0.412 54.66; 0.315 49.64 0428., 49.72 ? 0.332 56.461 0 449 AVG: 7 52.581 0 3581 45.1371 0 384 STD: 1 7.65? 0 053 6.85 0.052 Table 12: Outdoor Exposed (5 month) LWARP 1 LFILL 3 ..... _.__; LOAD EXTN.-- _J _.LQAD.__ _JEXIN :1. A i__-..§1:22;: 0.263 37.23 :5 0.293 53.37:? 0.303 24.692 0.245: f 54.423 0.325;: 33.69? 0.269: :3 51.33; 0.359[ 39.62; 0.269 :1 44.51; 0.321 :: 35.09: 0.266+ I 43.17; 0.264; 37.23? 0.272 j 52.00‘ 0.363T 39.033. 0.326 54.52 0.355 32.753 0.236 45.16 0.335 29.93? 0.263 37.29 0.293 26.36 0.320 55.301 0.369 26.36 . 0.241 36.46 ' 0.247 24.11 T 0.235 46.60 0.306 27.92 0.265 59.25 0.357 36.30 0.293 51.17 0.316 37.74 0.316 AVG-:- 47.72. 0.323 32.66 0.260 STD: 6.03 0.041 . 5.33.: 0.030 C 1 36.19‘T 0.260 42.95 0.326 45.02 0.293 26.94 0.263 46.39 0.266 31 .76 0.331 43.03 0.232 42.20 0.377 41.26 0.256 23.60 0.347 56.66 0.334 55.33 0.390 40.69 0.315 34.47 0.216 30.31 0.160 34.62 0.243 27.46 0.163 37.40 0.265 43.97 0.269 33.29 0.250 37.05 0.346 44.32 0.427 34.36 0.279 36.07 ‘ 0.350 42.44 0.254 39.65 ‘ 0307* AVG: 40.40 0.270 37.45 0.316 STD: 7.57 0.051 7.93: 0.061 EXTENSION (In) OUTDOOR EXPOSED (warp) Extension Vs. Time Sample A 08 I y = 0.64849 - 7.1soao-2x F142 .-. 0.903 0 0 I I r T r ' O 1 2 3 4 5 6 TIME (month) 100 OUTDOOR EXPOSED (warp) Extension Vs. Tlme Sample 8 0.8 ’ y = 0.75582 - 0.12139x W2 = 0.826 0.6 4 0.4 '1 EXTENSION (In) 0.2“ 0.0 r I ' I ' T ' I ' 0 1 2 3 4 5 TIME (month) Fig. 52: Outdoor Exposed, Extension Vs. Time, Sample 8 (warp) EXTENSION (In) 101 OUTDOOR EXPOSED (warp) Extension Vs. Time Sample c 0.6 '- 0.4 '3 0.2- y = 0.66645 - 8.18269-2x 642 = 0.909 0W6 0.0 _'— ' I V r ‘ 2 3 4 5 TIME (month) A Fig.53: Outdoor Exposed, Extension Vs. Time, Sample 0 (warp) EXTENSION (In) 102 OUTDOOR EXPOSED (fill) Extension Vs. Time Sample A 0.8 7 y = 0.57M? - 6.47809-2x W2 = 0,824 0.0 . , . f , I T TIME (month) Fig.54: Outdoor Exposed, ExtensionVs.Time,SempieA(iil) EXTENSION (In) 103 OUTDOOR EXPOSED (fill) Extension Vs. Time Sample 8 0.6 I . y = 0.72215 - 0.14269x F142 = 0.669 A 0.6 - A EXTN B 0.4 - A A 0.2 - d 0.0 , . , . , T 0 1 2 3 4 5955‘ www.mensionVs.Tm,Saaneam TIME (month) EXTENSION (In) 104 OUTDOOR EXPOSED (fill) Extension Vs. Time Sample 0 0.8 0.6 - 0.4 - 02.. y = 0.60912 - 6.13630-2x 9‘2 = 0.905 0.0 TIME (month) Fig. 56: Outdoor Exposed, Extension Vs. Time, Sample 0 GI!) 105 Table 13: OUV Exposed \‘IA 10057193“; WARP .3 572:1. 1;.-- L069 22:67.76- _-,._.;-_Z_9949-2957.13. -7 7"}7366 5.; 105-90;; __Q-§?,- R 2037* ”£249? -12..-- 2.2.294 20 2229921.. _§.1_58..,_.___,9699, 2.2 116 7c 0.625 7 73.46 051.0 7““ ' - 3775: 7:256 7*‘7§?:§:=LL:: “237, Ave: T 102. 40‘; "01641: ”“6971 ; _0606 6T0= ” “‘6'1'17'911“"0T027; i 5509: 07019 .2. _ J ,2 3 2, 76AMPL_EET: 67 097 0.510; _9.?;Z$;_ _ 07555 7 90 62 0 663‘ 97 72 0 561 96. 97; 0.5447 99_. 60 0.741 7_ 7 110 307 0.69177 11_4_.5g ___65591“ AVG: 96. 307 0.6077 102 90: 0_._ 670 STD: 7 #105397 0093: 7.79: 0.077 L . 1' SAMPLE C7 66.99; 0.6057 76.677 0.446 95.50; 0.6637 79.547 0.467 91.577 0.7467 70.74; 0.516 7 95.57 7 0.639 73. 77 0.479: AVG: 7 91.667 0.6697 75.737 0.462 STD: j 2.617 0.0627 4.219: 0.029 3 1 J = L200 HRS :; ______,__:____:_7_____ 7 SAMPLE AJ. 5478‘. 035.70: 912,222,295? 1 79 03‘ 0.642% 61 667 0.407 7 66 43 0.519i 75137M5‘L75 103 60 0 610:; 72.91; __0535 AVG: 7 69.01 . 0. 610 67 64 0.472 STD: 7 10.597 0 030 7.207 0.052 J J W m EAMPLE BJ 93.637 0.5047 39.14% 0.165 89.907 0 4707 32770? 0.146 66.667 0 466 30.507 0.169 7 95.36% 0 591 . 26.20; 0129 Ave: 7 91.443 0.506: 32.14? 0.151 STD: 3.937 0.0567 5.39:: 0.019 J L SAMPLE C2 63 411 0.396; 62.157 0:371 65 21’ 0.5027 67.337 0.521 61 723 0 320: 60 54 0.505 - ..,7.9:61...95§3 7292-.. 5759.3: AVG : 65727‘ 0 420'; 63 34: 0.4751 6T0 1 3.92 0 060: 2.90 0.070 Table 13 (oont’d) 106 250 HRS '7'WAP1P 1 761LL 1. [LOADA “163m 1 LOAD iEXTN “97166667177 “""‘9’4.—g‘517‘_55091“““ 65397—77" 91722. _ 93.617 0.566; 53.05; 0.433 7 66.70 0.5231 54.74 0.404 7 63.761 0.476: 71.61"; 0.404 AVG: 90.09 0.5197 61.501 0.425 6713”: 4.67 0.0377 9.08? 0.027 1 : SAMPLE B? 99927 0.5107 17.327 0.106 79.54? 0.5057 13.13 0.112 90.047 0.493’ 15.22 0.149 94.011 0.497 7.61 0.170 AVG: 90.66 0.501 13.37' 0.134 767 : 6.56 0.0081 4.06 0.030 SAMPLE C _._42 0.417 46.05 0.461 66.79 0.493 66.13 0.474 49.02 0.427 67.14 0.450 66.56 0.455 57.64 033.9. AVG: 68.70 0.446 60.24 0.434 STD: 15.47 0.034 9.40 0.071 300 HRS SAMPLE A1 66.68; 0.390.. 47.22 0.303 65.34 0.423 45.16 0.264 57.15 0.346 69.64 0.406 66.65 0.371 60.27 0.429 AVG: 64.01 0.363 55.56 0.35? STD: 4.62 0.032 11.51 0.080 SAMPLE B; 47.11 0.362. 10.851 0.366 65.18 0.353 15.307 0.565 61.64 0.377 10.07 0.457 65.07 0.363 14.71 0.416 AVG: 59.75 0.3747 12.731 0.457 STD: 6.59 0.0147 2.65 0.093 SAMPLE C 64.56 0.416; 54.42; 0.527 60.11 0.3677 61.297 0.523 7 41.65 0.2647 47.647 0.454 1 71.091 0.407: 51.521 032.1. AVG: ' 59.407 0.364 53.777 0.471 STD: 12. 54 0.070 5.69! 0.069 Table 13 (oom’d) 107 350 HRS 'WARP . :FILL E LOAD TEXIN __ jLOAD ___‘___~_§__E__>g_1~54}<.__,i SAMPLE A 54.471r 0.299} 47.54 § 0.33% 1 57-34 0:279 4.5.99.1-” .02-3323.8. T 63.41: 0.386 42.34 0.309 ' 6.5.951---.__.9§ 22.1-2..- 3.9...09;__._.__.9.299. AVG: 60.633} 0.334 44.731 0.319 STD: ; 5.31 T 0053,? 2.46% 0.018 I 1 1 5 ' SAMPLE 81 67.11 ' 0.336 1 61.26 0.281 . 65.69 0.343 63.65 0.360 AVG: 64.43 0.330 STD: 2.54 0.034 1% 1 SAMPLE c_ 61.02 0.363 53.07 0.377 ' 52.11 0.266 53.74 . 0.409 60.08 0.317 53.96’ 0.340 63.92 0.371 43.52 0.350 AVG: 59.28 . 0.329} 51.07 0.369 STD: 5.05 0.048‘ 5.05 0.031 400 HRS SAMPLE A 57.801 0.336 43.70 0.276 53.05 0.340 38.89 0.305 41.58 0.239 49.02 0.319 47.33 0.278 48.54 0.285 AVG: 49.94 0.298 44.54 0.296 STD: 7.03 0.049 5.64 0.019 SAMPLE c: 31 .52 0.240 . 57.26 , 0.316 45.26 0.365 T 4706} 0.345 46.90 0.297 40.891 0.405 41991. 0.236 38.52 0.397 AVG = 41.421 0.285 45.93 . 0.366} STD: 6.91T 0.060. 8.371 0.043 Table 13 (cont’d) 108 '450 HBLTfi—AR'P A.“ ;'1-’1LL_ } . }LOAD fliEXTN }, LOAD jEXTN “SAM‘L‘E‘ATTmgr'T“0fij;75j“T“‘é‘ofs‘zw—bi‘i’e‘g“ 1 41.13? 0.238} 27.87T 0.219 T 38.74; 0.311} 21.58? 0.188 1 46.71} 0.255} 26.68? 0.2261 AVG: 44.14 5 0.270} 24.19} 0.201} STD: 5.13? 0.031} 3.62} 0.027 1 i i _ T SAMPLE c 48.59;? 0.355; 54.15T 0.389 44.16 1 0.328} 40.56 0.290 57.26} 0.362} 43.65} 0.279 55.68? 0.329} 45.58} 0.263 AVG: 51.42 0.344% 45.99T 0.305 STD: 6.14 0.018} 5.82 0.057 500 HRS SAMPLE A 19.79 g 0.148} 25.64 0.196 25.69' 0.179" 19.41 0.180 22.63 0.155 24.40 0.188“ 23.03 0.158 19.33 0.214 AVG: 22.79 0.160 22.20 0.195 STD: 2.41 0.013 3.30 0.015 SAMPLE c 44.00 0.217 44.38 0.266 27.46 0.174 29.32 0.381 32.30 0.201 43.06 0.307 25.45 0.181 A 35.36 0.320 AVG: 32.30 0.1937 38.03 0.319 STD: 8.31 0.020 7.04 0.048 550 HRS SAMPLE A 19.46 0.139 3.79 0.095 10.60 0.172 12.62 0.171 10.85 0.177 4.86 0.105 10.85 0.125 13.50 0.137 AVG: 12.94 0.1531 8.69 0.127 STD: 4.35 0.025 5.08 0.034 SAMPLE C 23.57 0.222 38.01 0.296 27.84} 0.196} 27.60} 0.2397 30.74} 0.199} 2569‘ 0.269“ (36.st 0.220} 24.30 0.178 AVG: 29.63 0.209} 28.90 0.246 STD: 5.38 0.014} 6.22} 0.051 Table 13 (oont’d) 109 ‘ 600 HRS 1WARP } }F1LL , TLOADMMLEXTN TLOAD 115.24me SAMPLE A2 561‘} 0.091} 3332*..- 0:094 1.18} 0.121 } 3.3_8};___.0;0_7fi7 12.91} 0.343} 4.97} 0.111 3.11 } 0.270} 591T” 0122} AVG: 570’ 0.206} 4.37}; 0.101 STD: 5.13 0.120} 1.29} 0.020 1 s SAMPLE c. 29.48 0.186 40.693 0.353 1 42.36 0.231 31.92} 0.227 27.49 0.177 28.81 } 0.230 AVG: 33.11 0.198 33.81 T 0.270 STD: 8.07 0.029 6.16} 0.072 I 700 HRS } SAMPLEC 13.23’ 0.111 16.11' 0.116 1 19.84 0.141 13.48 0.171 11.60 0.175 22.01 0.157 6.74 0.069 11.87}. 0.117 AVG: 12.85 0.124 15.87} 0.140 STD: 5.41 0.045 4.45} 0.028 1 T 800 HRS } . } SAMPLE c} 3.14 0.095 4.13 } 0.0891 T 0.83 0.070 3.92 i 0.108 ' 5.99 0.235 1.07 0.089 1.40 0.085 2.20 0.128 AVG: 2.84 0.121 2.83 0.104 STD: 2.32 0.077 1.46 0.019 EXTENSION (In) 110 GUV EXPOSED (fill) Extension Vs. Time Sample A 0.8 - y : 0.57210 - 6.95429-4x m2 = 0.926 I EXTENSIONA 0.6 - 0.4 - 0.2 - 0.0 1 V r t I T I U j f t t 0 200 400 600 800 1000 TIME (hour) Fig. 57: qu Exposed, Extension Vs. Time, Sample A (1111) EXTENSION (In) 111 OUV EXPOSED (fill) Extension Vs. Time Sample 3 0.8 . y : 0.50945 - 7.206264)! 8A2 : 0.594 A 0.6 - AL EXHBEKJVB " fir f r j’ r I I o 200 400 600 800 TIME (hour) 0.0 v A ? A A A L ? i; 1000 F1958: OUV Exposed, Extension Vs. Time, Sample 8 (fill) 112 OUV EXPOSED (fill) Extension Vs. Time Sample C 0.8 1 y = 0.61236 - 6.3989e-4x R62 = 0.967 ‘D 0 90811610111 0 0.6 - 0.4 '1 EXTENSION (In) 0.2‘ 0.0 ' ' | V V I v v 1 v v I v 0 200 400 600 800 1000 TIME (hour) Fig. 59: OUV Exposed, Extension Vs. Time, Sample C (fill) EXTENSION (In) 113 OUV EXPOSED (warp) Extension Vs. Time Sample A 0 8 ; y = 0.66198 - 7.98869-4x Fi"2 a: 0.910 0.6 _ EXTENSION A 0.4 ' 0.2 -' 0.0 . . . . . . . . . . . . 0 200 400 600 800 1000 TIME (hour) Fig.60: OUVExposed,ExtensionVs.TimeSamplsA (warp) EXTENSION (In) 114 OUV EXPOSED (warp) Extension Vs. Time Sample B 0.8 J) y = 0.51780 - 7.30590-4x F162 = 0.630 0.6 - A A. EX"3E%JVB . . , . . . . 0 200 400 600 800 1000 Fig. 61: OW Exposed. Extension Vs. Time Sample 6 (warp) EXTENSION (In) 115 OUV EXPOSED (warp) Extension Vs. Time Sample C 0.8 1’ y = 0.63032 - 7.06010-4x F102 = 0.912 0.0 ' ‘ ' I ' ‘ V r V U T I V I f ' I V i o 200 400 600 800 1000 TIME (hour) Fig. 62: OUV Exposed, Extension Vs. Time Sample 0 (warp) 116 Table 14: 96 Elongation as Function ofx (time) INITIAL WARP 96ELONGATION A 0.237933 8 0.244933 C 0.2461 33 FILL A 0.21 7167 8 0.258533 C 0.2212 Y:%EL0NGAT10N(1nnn) \l 0.5 0.118967 0.122467 0.123067 0.108583 0.129267 0.1106 OUTDOOR (MONTHS) WARP 8 M X A 0.64849 -0.0719 7.364412 8 0.75582 -0.12139 5.21 7508 C 0.66645 -0.08183 6.640717 FILL B M X A 0.57007 -0.06478 7.123907 B 0.72215 -0.01 427 41.55045 C 0.60912 -0.061 36 8-124114 QUV (HOURS) WARP B M X A 0.66198 —0.0008 679.7353 8 0.5178 -0.00073 541.1152 C 0.63032 -0.00071 718.479 FILL 8 M X A 0.5721 -0.0007 666.5277 8 0.50945 -0.00072 527.5781 C 0.61236 -0.00064 784.1348 CARBON ARC (HOURS) WARP B M X A 0.6065 -0.00033 1488.197 B 0.68354 ~0.00055 1022.178 C 0.751 96 -0.00082 769.8535 FILL B M X A 0.55886 -0.00076 594.3462 8 0.6828 -0.001 46 379.0805 C 0.6616 -0.00054 1022.833 0.6 0.14276 0.14696 0.14768 0.1303 0.15512 0.13272 Y=MX+ 8 X: (Y-B)/M X 7.033503 5.01 5734 6.339916 X 6.788669 39.73859 7.763636 X 649.9512 507.5898 683.61 64 X 635.2995 491 .7016 749.5663 X 1 415.568 977.5551 739.7233 X 565.6811 361 .3752 981 .7709 Y 0.7 0.166553 0.171453 0.172293 0.152017 0.180973 0.15484 X 6.702595 4.81 3961 6.0391 16 X 6.453432 37.92674 7.4031 58 X 620.1 671 474.0643 648.7538 X 604.0714 455.8251 714.9979 X 1 342.939 932.9325 709.5932 X 537.01 6 343.6698 940.7091 Y 08 0.190347 0.195947 0.196907 0.173733 0.206827 0.17696 X 6.371686 4.612187 5.738315 X 6.118195 36.11489 7.04268 X 590.383 440.5389 61 3.8912 X 572.8433 41 9.9486 680.4294 X 1 270.309 888.31 679.463 X 508.3509 325.9645 899.6473 09 0.21414 0.22044 0.22152 0.19545 0.23268 0.19908 X 6.040777 4.410413 5.437514 X 5.782958 34.30303 6.682203 X 560.5989 407.01 35 579.0286 X 541 .61 51 384.072 645.861 X 1 1 97.68 843.6874 649.3328 X 479.6859 308.2591 858.5855 CARBON ARC 117 CARBON ABC 8: OUV (warp) TIME (% elongation) 1600 J y : 744.81 + 0.43069x R42 : 0.020 ‘ 1400 - " B 1200 3 a 1000 - J I ‘ 8m .1 - B I 600 . . . . . . . 400 500 600 700 800 OUV F1963: CarbonAro&OUV(warp)-%Elonoetion CARBON ARC 118 CARBON ARC & OUTDOOR (warp) 11ME (% elongation) 1600 y = 7.2496 +168.82x R42 = 0.296 F1964: CarbonAro&Outdoor(warp)-%Eiongetlon OUV 119 OUTDOOR a. OUV (warp) 11ME (% elongation) y: 47.62 + 91.145x R62 = 0.802 OUTDOOR F1965: Outdoor&OUV(werp)-%Elongm CARBON ARC 120 CARBON ARC & OUV (fill) TIME (% elongation) 1200 y= - 503334201221: R42=0.862 1000 ~ 800 1 . 600 .1 400 4 2m I ' T ' I i I 300 400 500 600 700 OUV Fig.66: CarbonArc&OUV(Iill)-%Elonoatlon 800 OUV 121 OUTDOOR & ouv (fill) TIME (% elongation) 600 I a y : 697.66 - 6.1429x R62 : 0.600 I 700 - I 600 - 500 - 400 - I 4 300 T f T ' I ' T ' 0 1o 20 30 40 50 OUTDOOR Hg.67: Omdoor&OUV(1ill)-%Elongation CARBON ARC 122 OUTDOOR 8: CARBON ARC (till) TIME (% elongation) 1200 ‘ y = 816.53 - 12.1311: R42 = 0.499 1000 a : . I I I I am .1 600 4 I I d I I I m -1 . I 1 ' . 200 ' I I I I I ' T I 0 10 20 30 40 50 Fig.68: Outdoor&CarbonAro(1iI)-%Eiongetion LIST OF REFERENCES Brennan, Patrick and Carol Fedor, ”Sunlight, UV and Accelerated Weathering“, O-Panel, poster, undated. Carlsson, D.J., K.H. Chan, J.P. Tovborg Jensen, D.M. Wiles and J. Durmis, “Hindered Amines as Antioxidants in UV Exposed Polymers“, Pgmmer Additives, New York: Plenum Press, 1984, 35-47. Cicchetti, 0., ”Mechanisms of Oxidative Photodegradation and of UV Stabilization of Polyolefins", W, 1970, 7(112):70-105. Crewdson, Lesley F.E., "Corrrelation of Outdoor and Laboratory Accelerated Weathering Tests at Currently Used and Higher lrrandiance Levels-Part II”, W, 4th Quarter 1993, 23(46). 1 f h mi l ”Plastics, Environmentally Degradable“, New York: John \Mley & Sons, Inc., 1984, no author, 626-648. Fischer, Richard, " W", SAE Technical Paper Series, New York: Copyright Clearance Center, 1984, August 6-9; 1-9b. Fischer, RM. and W.D. Ketola, "The Use of a Nonparametric Statistics in Accelerated Weathering Test Design and Development', fiEEEQfiexigw Issue, Fall-Winter 1993, 11(2):9-14. Grassla. Norman and Gerald Scott. “W1 New York: Cambridge University Press, 1985. Grossman, George W. "Correlation of Laboratory to Natural Weathering" , W99! Oct 1977 49(633) 45-54 Hardy, Vlfilliam 8., “Light Stabilization of Polymers, Part I of II“, 51W ' Summer 1983, 13(30) a. Hardy, William 8., ”Light Stabilization of Polymers, Part II of H", W, Autumn 1988, 13(31) b. Hawkins, W. Uncolm. ”WW1 Springer- Verlag, 1984. 123 124 let, Robert C and Norma D. Searle, “Energy Characteristics of Outdoor and Indoor Exposure Sources and Their Relation to the Weatherability of PIBSfiCS'AQQlIfiCLEQIVWB. 1967. 4:61~83. Kelen, TIbor, " ' Mchgue, F. H. and M. Blumberg, 'Factors Affecting Light Resistance of Polypropylene“.Annued_thLmaL§1anSJa. 1967. 4:175-188. Mltett, Steve, Personal CommuniCation, May 12, 1993. W. The OUV compared to Sunshine Carbon Arc“, 1988. Schweitzer. Philip A.. W New York: Marcel Dekker, Inc., 1987. Searle, Norma D., ”Activation Spectra the Activation Spectrum and its Significance to Weathering of Polymeric Materials", Wm, Fall 1984, 14(33):1-5. Searle, Norma D., “Wavelength Sensitivity of Polymers”, ANIEQ, 1986, 62-74 D. Seppala. J, Y-Y. Linko, and T. Su, - W". Helsinki: Finnish Academy of Technology, 1991, Tobin, Mlliam, and Fred VIgeant, “Ultraviolet Stabilization Systems“, Elastic: Commuting. 1981, Sept/Oct, 4:16-24. ICH IES 111111111111111