Weight Loss Of Films Research Articles

Efficient enzymatic degradation of poly (ɛ-caprolactone) by an engineered bifunctional lipase-cutinase

Lipases and cutinases belong to esterase family and can be used as biocatalysts for poly (ɛ-caprolactone) (PCL) degradation and recycling. A number of synthetic fusion enzymes with two or more catalytic domains were reported to be superior to the parental enzymes or their mixture for many biotechnological applications but rarely for the polyester biodegradation. To develop a more efficient biocatalyst for poly (ɛ-caprolactone) (PCL) degradation and recycling, a bifunctional lipase-cutinase (Lip-Cut) constructed by end-to-end fusion was successfully overexpressed in Pichia pastoris with 0.9% of methanol induction at pH 6.0 and temperature 27 °C. Lip-Cut displayed more efficient poly (ɛ-caprolactone) degradation capability, and the weight loss of PCL film by Lip-Cut at 6 h was 13.3, 11.8 and 5.7 times higher than that by Lip, Cut and Lip/Cut mixture, respectively. GC-MS analysis of the degraded products of PCL revealed that the mainly degraded product was 6-hydroxyhexanoic acid and small ratio of ɛ-caprolactone. Our results demonstrated that the proper construction of bifunctional lipase-cutinase could enhance the synergistic action of two moieties due to the complementary properties of both enzymes in substrate specificity and hydrolysis pattern. The method provided an effective approach to engineer more efficient biocatalyst for bio-application in degradation and recycling of PCL.

The Mechanical Properties of Poly(Methyl Methacrylate) (PMMA)/ZrO2 Nanocomposite Polymer Films

The composite films of Polymethylmethacrylate (PMMA) with ZrO2 at different weight percentage have been used for measurement of Mechanical properties such as stress, strain, and Young’s modulus at room temperature using the Universal Testing Machine. The value of stress is increased linearly with strain up to the stress at break and afterwards shown discontinuity. The properties of stress and strain increased as weight percentage of ZrO2 increased with PMMA and at 60 weight percent the stress in increased linearly up to 2.18 MPa with strain. The tensile strength, load at break and stress at break of the composite film of PMMA with ZrO2 is increased as weight percentage increased. Further, the weight loss and melting temperature of the composite films for pristine and for irradiation by electron beam at dose rate of 100 kGy were measured using Thermo Gravimetric Analysis and Differential Scanning Calorimeter. The weight loss of the composite film after electron irradiation is higher than that of its pristine. It is observed from DSC that melting peak is occurred at temperature 397.52 °C for pristine and at 395.94 °C after electron irradiation. Hence change in melting temperature is found to be 1.58 °C. The prepared composite films are characterized by using FTIR over the range of 3500– 500 wavenumbers (cm−1).

The Effect of Acetylation on the Hydrolytic Degradation of PLA/Clay Nanocomposites

In this study, the hydrolytic degradation of Poly(lactic acid) (PLA) and acetylated PLA (PLA-Ac)–clay nanocomposites were investigated. The organo clay was obtained by ion exchange reaction using cetyl tri methyl ammonium bromide (CTAB). Nanocomposites containing 2, 5 and 8% mass ratio of organo clay (CTAB-O) were prepared. PLA and its organo clay nanocomposites were characterized by scanning electron microscope (SEM), thermo gravimetric analysis (TGA) and X-ray diffraction (XRD) to determine the morphology before and after hydrolytic degradation. Fourier transform infrared (FTIR) analyses of PLA and PLA-Ac were also obtained. The hydrolytic degradation of polymers and their composites were investigated in the phosphate buffered saline solution (PBS). The results showed that controlled hydrolytic degradation was observed in the samples with end group modification of PLA. While weight loss of PLA films was 28%, that of PLA-Ac films was 18% after 60 days degradation time. The weight loss was obtained as 29.5 and 25.5% for PLA-5 wt% organo clay (PLA/5CTAB-O) and PLA-Ac-5 wt% organo clay (PLA-Ac/5CTAB-O) nanocomposites films, respectively. It was also observed that thermal degradation of PLA-Ac was much more than that of PLA. Hydrolytic degradation increased depending on organo clay content. The end group modificated PLA results in controlled hydrolytic degradation. While hydrolytic degradation in polymer films occurred as surface erosion, bulk erosion was observed in composite films.

Isolation and role of polylactic acid-degrading bacteria on degrading enzymes productions and PLA biodegradability at mesophilic conditions

Enumeration and isolation of polylactic acid (PLA)-degrading bacteria from soils and wastewater sludge were performed on emulsified PLA agar. Two isolates of potent PLA-degrading bacteria, designated as CH1 and WS3, were selected and identified as Stenotrophomonas pavanii and Pseudomonas geniculata, respectively. PLA was presented as a substrate to stimulate production of protease and PLA-degrading enzyme by S. pavanii CH1 and P. geniculata WS3. The optimal pH values for both protease and PLA-degrading enzyme production by S. pavanii CH1 and P. geniculata WS3 were 7.5 and 8.0, respectively. The optimal gelatin concentrations for stimulating protease production in S. pavanii CH1 and P. geniculata WS3 were 0.3% (w/v), while those for PLA-degrading enzyme production in S. pavanii CH1 and P. geniculata WS3 were 0.1 and 0.3% (w/v), respectively. In addition, P. geniculata WS3 had a higher percentage of PLA film-weight loss than that of S. pavanii CH1, corresponding with reduced molecular weight of PLA. A significant increase of lactic acid content in culture broth was directly correlated with the increasing percentage of PLA film-weight loss. Our results clearly demonstrated that P. geniculata WS3, a novel isolated bacterium, has played a substantial role in PLA biodegradation by producing PLA-degrading enzyme and adhering on PLA surface.

Preparation and characterization of biocomposite chitosan film containing Perilla frutescens (L.) Britt. essential oil

In the present study, biocomposite films with incorporated Perilla frutescens (L.) Britt. essential oil (PEO) were prepared using the solvent casting method. Perilla essential oil concentrations at 0.2%, 0.6%, and 1.0% (v/v) had a significant effect on the physical, chemical, and antibacterial activity of the films. Films with PEO exhibited a significant decrease (p < 0.05) in tensile strength (TS), elongation at break (%E), water vapor permeability (WVP), water solubility (WS), and swelling ratio (SR). The amounts of PEO had a significant effect on the WVP, WS, and SR but had no significant effect on the TS and%E (p < 0.05). Addition of PEO to the chitosan film significantly improved the ultraviolet–visible-light barrier of the film. The antimicrobial properties of the films were significantly enhanced by PEO. An increased roughness of the biocomposite films with added PEO was shown by scanning electron microscopy. Fourier transform infrared spectroscopy showed new interactions in the biocomposite films. X-ray diffraction measurements confirmed that the films with PEO have more dense crystalline domains in comparison with the pure chitosan film samples. Furthermore, the thermal stability of the film decreased upon PEO addition, and the weight loss of films with PEO increased with increasing amount of PEO, as suggested by thermogravimetric analyses. The biocomposite films with incorporated PEO demonstrated good activity against Escherichia coli, Staphylococcus aureus, and Bacillus subtilis, showing inhibition zone diameters (mm) of 24.563 ± 0.021 mm, 20.153 ± 0.006 mm, and 23.427 ± 0.015 mm, respectively. Overall, the biocomposite chitosan film with added PEO have potential application for food preservation as a biodegradable and ecofriendly packaging material.

Purification and characterization of cutinase from Bacillus sp. KY0701 isolated from plastic wastes

ABSTRACTA total of approximately 400 bacterial strains were isolated from 73 plastic wastes collected from 14 different regions. Nineteen isolates that form clear zones both on tributyrin and poly ε-caprolactone (PCL) agar, were identified based on 16S rRNA gene sequences. Among these, Bacillus sp. KY0701 that caused the highest weight loss of PCL films in minimal salt medium, was selected for cutinase production. The highest enzyme activity (15 U/mL) was obtained after 4 days of incubation at 50°C, pH 7.0 and 200 rpm in a liquid medium containing 1.5% (w/v) apple cutin and 0.1% (w/v) yeast extract. The purified enzyme was stable at high temperatures (50–70°C) and over a wide pH range (5.5–9.0). The relative activity of cutinase was at least 75% in the percent of various organic solvents. The apparent Km and Vmax values of the cutinase for p-nitrophenyl butyrate were 0.72 mM and 336.8 µmol p-nitrophenol/h/g, respectively. In addition, it showed high stability and compatibility with commercial detergents. These features of cutinase obtained from Bacillus sp. KY0701 make it a promising candidate for application in the detergent and chemical industries. In our best knowledge, this is the first report for cutinase production and characterization produced by a Bacillus strain.

Localized corrosion of pressure vessel steel in a boiling water reactor cladding flaw – modeling of electrochemical conditions and dedicated experiments

Stress corrosion cracking (SCC) tests performed in oxygenated high-temperature water with compact tension (CT) specimens have indicated that very small concentrations of chloride accelerate significantly the rate of crack growth in low-alloyed steels (LAS). In the present work, the electrochemical conditions in a CT specimen are simulated and compared to those in a cladding flaw. The Cl− and Fe2+ concentrations and the corrosion potential are predicted to be significantly higher in the crevice of a CT specimen than in the cladding flaw, whereas pH is significantly lower. Thus, a much more aggressive environment is established in the CT specimen. General corrosion rates of LAS in the presence of chloride, estimated by impedance spectroscopy, weight loss and thickness of oxide films, increase significantly at potentials more positive than the corrosion potential. In addition, slow strain rate tests showed susceptibility to SCC at E>−0.3V vs. SHE, the tendency increasing with potential. It can be concluded that due to the higher potential in the crevice of CT specimen, determined by a more aggressive chemistry, the conditions within it are not representative for a realistic cladding flaw.

In vivo degradation of poly (ε-caprolactone) films in Gastro Intestinal (GI) tract

The degradation of PCL implant in gastrointestinal tract (stomach and intestine) was investigated in vivo. The biodegradation of PCL films after implantation in stomach and intestinal part of rats were investigated. At 3, 7, 17 and 28days post implantation, the films were retrieved and evaluated for studying the degradation rate. The comparison of results revealed that PCL degraded more in intestinal region than in stomach. The extent of degradation was determined by measuring the change in weight loss, crystallinity, morphology and molecular weight distribution. In GI tract, the explanted PCL films from both intestine and stomach followed different degradation pathway, at different pH range and enzymes produced distinct morphology and crystallinity. Histological examination of the in vivo tissue samples revealed mild inflammation and negligible adverse effects. When results compared to polymer films degraded at stomach, the pancreatic lipase enhanced the weight loss of PCL films in intestine. Degraded PCL films in intestine showed enzymatic surface erosion by lipase as well as hydrolytic mechanism in slightly alkaline environment whereas in stomach the results are consistent with bulk erosion. In both intestine and stomach, the polymer films presented a significant decrease in molecular weight distribution.

Biodegradability of chemically synthesized syndiotactic poly(β-[R]- hydroxybutyrate) in soil of Northeast China

Degradation of syndiotactic poly([R]-b-hydroxybutyrate) (syn-PHB), a chemically synthesized PHB, was investigated in this study by incubation polymer films in a soil of northeastern China. During incubation, progressive weight loss of the syn-PHB films and a corresponding decrease of molecular weight were observed over the 90 days of incubation indicating the biodegradation of syn-PHB and the random cleavage of ester bonds. Microorganisms isolated and identified from the partially degraded films included Pseudomonas spp., Alcaligenese sp., and Comamonas sp. Our results suggest that chemically synthesized syn-PHB is biodegradable under aerobic conditions in soil.

Control of biodegradability of triple-mixed aliphatic polyester films with calcined calcium oxide fine powder

Biodegradable mulch films are important agricultural materials for environmental protection and labor savings. To investigate the effect of calcium oxide fine powder on the degradation behavior of triple-mixed aliphatic polyester, films were prepared by thermal kneading a triple-mixed plastic matrix with calcined calcium oxide fine powder derived from scallop shells, followed by an inflation method. Three kinds of commercial biodegradable aliphatic polyesters, poly(lactic acid), poly(butylene succinate-co-adipate), and poly(butylene succinate-co-lactate), were mixed to form the triple-mixed matrix. The resulting films and, for comparison, two types of commercial mulch films, poly(butylene succinate) and poly(butylene adipate-co-terephthalate), were investigated using hydrolysis and soil burial tests for 180 d. The biodegradability of these films was examined by observing the time evolution of film weight loss, total organic carbon content, pH of the medium, and surface morphology using scanning electron microscopy. Addition of calcium oxide fine powder as a modifier significantly accelerated the speed of film degradation, and as the amount of CaO added was increased, the film degradation rate as well as the ability to suppress the acidification produced by the organic acids increased. As a result, quick-acting composite films containing a large proportion of poly(butylene succinate-co-adipate) were successfully prepared in this study.

Degradation of PVC/rPLA Thick Films in Soil Burial Experiment

Some of the biodegradable polymers can be blended with a synthetic polymer to facilitate their biodegradation in the environment. The objective of the study was to investigate the biodegradation of thick films of poly(vinyl chloride)/recycled polylactide (PVC/rPLA). The experiments were carried out in the garden soil or in the mixture of garden soil and hydrocarbon-contaminated soil under laboratory conditions. Since it is widely accepted that the biosurfactants secreted by microorganisms enable biotransformation of various hydrophobic substances in the environment, it was assumed that the use of contaminated soil, rich in biosurfactant producing bacteria, may accelerate biodegradation of plastics. After the experimental period, the more noticeable weight loss of polymer films was observed after incubation in the garden soil. However, more pronounced changes in the film surface morphology and chemical structure as well as decrease of tensile strength were observed after incubation of films in the mixture of garden and contaminated soil. It turned out that as a result of competition between two distinct groups of microorganisms present in the mixture of garden and hydrocarbon-contaminated soils the number of microorganisms and their activity were lower than the activity of indigenous microflora of garden soil as well as the amount of secreted biosurfactants towards plastics.

Microbial degradation of low density polyethylene

Low‐density polyethylene (LDPE) is potential source of environmental pollution. In this study, biodegradation of LDPE was achieved by employing fungus and actinobacteria isolated from waste dumping site. Among all the isolates, two potential strains were obtained through enrichment technique. Based on 18S rRNA and 16S rRNA analyses the isolated strains were identified as Aspergillus nomius and Streptomyces sp., respectively. The biodegradation of LDPE was determined by evaluating weight loss and morphological changes of the LDPE samples. The isolated strains; Aspergillus nomius had the capacity to degrade 4.9% and Streptomyces sp. showed 5.2% of weight loss of LDPE films respectively. Weight loss of LDPE film after inoculation of isolates in degradation medium indicated that it was capable of using polyethylene as carbon and energy source. CO2 evolution was checked after degradation of polyethylene pieces, the level of CO2 reached 2.85 g L−1 in the presence of Aspergillus nomius and Streptomyces sp. produced 4.27 g L−1. Sophisticated instrumentation was used like atomic force microscopy, Fourier transform infra‐red spectroscopy (FTIR). The breakdown products of the LDPE film after exposure to the isolates was recorded employing GCMS. FTIR spectrum of LDPE film confirmed changes in the presence of chemical groups like amine, alkanes, phenols, and alcohol after degradation of LDPE films by Aspergillus nomius and Streptomyces sp. and the most prominent structural changes of the spectrum were observed in the LDPE sample after 90 days of degradation. The results affirmed the isolates were capable of degrading LPDE films efficiently. © 2016 American Institute of Chemical Engineers Environ Prog, 36: 147–154, 2017

In-situ imidization analysis in microscale thin films of an ester-type photosensitive polyimide for microelectronic packaging applications

The imidization reaction in thin films of an ester-type photosensitive polyimide is investigated in the temperature range of 50–450°C by temperature dependent rapid-scan in-situ FT-IR spectroscopy, thermo-ellipsometric analysis and thermogravimetric analysis coupled with evolved gas analysis. The influence of the UV crosslinkable methacrylic functional group in the polymer sidechain on the imidization reaction is studied. For non-crosslinked precursor films the imidization is completed at ≈250°C. Depending on the amount of crosslinking the temperature to achieve full imidization is shifted to higher values. Above a certain amount of crosslinking the degree of imidization is limited to ≈95% for temperatures below 280°C. The reaction continues by further increase of the temperature to >340°C. Evolved gas analyses indicate that the cleave-out of crosslinker is required to finish the imidization. The film shrinkage and weight loss is correlated to the degree of imidization.

Photostabilizing Efficiency of Poly(vinyl chloride) in the Presence of Organotin(IV) Complexes as Photostabilizers.

Three organotin complexes containing furosemide as a ligand (L), Ph3SnL, Me2SnL2 and Bu2SnL2, were synthesized and characterized. Octahedral geometry was proposed for the Me2SnL2 and Bu2SnL2, while the Ph3SnL complex has trigonal bipyramid geometry. The synthesized organotin complexes (0.5% by weight) were used as additives to improve the photostability of poly(vinyl chloride), PVC, (40 μm thickness) upon irradiation. The changes imposed on functional groups, weight loss and viscosity average molecular weight of PVC films were monitored. The experimental results show that the rate of photodegradation was reduced in the presence of the organotin additives. The quantum yield of the chain scission was found to be low (9.8 × 10−7) when Ph3SnL was used as a PVC photostabilizer compared to controlled PVC (5.18 × 10−6). In addition, the atomic force microscope images for the PVC films containing Ph3SnL2 after irradiation shows a smooth surface compared to the controlled films. The rate of PVC photostabilization was found to be highest for Ph3SnL followed by Bu2SnL2 and Me2SnL2. It has been suggested that the organotin complexes could act as hydrogen chloride scavengers, ultraviolet absorbers, peroxide decomposers and/or radical scavengers.

Preparation and characterization of pure and copper-doped PVC films

Abstract Pure and Cu2+-doped polyvinyl chloride (PVC) polymer films were prepared using the solution cast technique. Investigations were conducted using DSC, TGA, XRD, FT-IR, UV–Vis, SEM and EPR. Differential scanning calorimetry studies suggested that the Cu2+ samples have higher values of the glass transition (T g) temperature, and thermo gravimetric studies show that weight loss of polymer film indicates the improved thermal stability of the polymer film. The features of the complexation of the polymer films were studied by X-ray diffraction. FT-IR spectra exhibits the bands in three regions, which are attributed to C–Cl, C–C and numerous CH groups of stretching and bending vibrations. The absorption spectra have been recorded in the wavelength range 200–900 nm. The absorption edge, direct bandgap, indirect bandgap and urbach energy have been evaluated. Film morphology was examined by scanning electron microscopy. XRD, DSC and SEM reveal the amorphous nature and surface morphology of polymer films, respectively. Electron paramagnetic resonance studies were used to calculate the number of spins and paramagnetic susceptibility as a function of dopant concentration, all the Cu2+-doped PVC samples exhibit signal with g values g ⊥=2.176 and g ||=2.254. The observed variation in the EPR signal intensity is due to variation in the dopant concentration.

불소계 변성 폴리우레아의 합성 및 오존저항 특성

본 연구에서는 내 오존성을 향상시키기 위해 PFPE-diol을 도입하여 불소계 변성 폴리우레아를 합성하였다. 불소 함량에 따라 변성 폴리 우레아(PFDIA-10C, PFDIA-20C, PFDIA-30C)를 제조하였으며 각각의 폴리우레아는 불소를 10 wt%~30 wt% 포함하였다. 제조된 도막의 오존처리 전 후 질량변화를 조사하였고, 도막의 경도, 내마모성, 인장성능 그리고 신장율 등의 물성을 분석하였다. 또한 내 오존성 테스트(10 ppm, 336 h)후에 광학현미경을 통해 도막표면을 관찰한 결과 PFPE-diol의 함량이 20 wt% 이상 일 때 균열, 탈색 그리고 질량감소량에서 양호한 결과를 보여주어 도막의 내 오존성이 향상되었음을 알 수 있었다. FT-IR 분석을 통해 PFDIA 합성물의 O-H 피크가 불소 함량 증가함에 따라 감소하는 것을 확인하였다. The fluorine-containing modified polyurea was synthesized using the PTPE-diol to improve the ozone-resistance. Three types (PFDIA-10C, PFDIA-20C, PFDIA-30C) of the modified polyurea containing the fluorine content from 10 wt% to 30 wt% were prepared. After ozone treatment on the prepared films, the weight loss of film was investigated and analyzed the film properties such as hardness, wear resistance, tensile stress, elongation, etc. Also, the film surfaces were observed by the optical microscopy after ozone-resistance tests at 10 ppm for 336 h. It was shown that the defects such as the cracking, the bleaching and the mass loss were reduced and the ozone-resistance of films were improved when the contents of PFPE-diol are more than 20 wt%. It was found that the intensity of O-H peak in PFDIA compounds confirmed by FT-IR was decreased as fluorine contents were increasing.

A disulfide bridge in the calcium binding site of a polyester hydrolase increases its thermal stability and activity against polyethylene terephthalate.

Elevated reaction temperatures are crucial for the efficient enzymatic degradation of polyethylene terephthalate (PET). A disulfide bridge was introduced to the polyester hydrolase TfCut2 to substitute its calcium binding site. The melting point of the resulting variant increased to 94.7 °C (wild‐type TfCut2: 69.8 °C) and its half‐inactivation temperature to 84.6 °C (TfCut2: 67.3 °C). The variant D204C‐E253C‐D174R obtained by introducing further mutations at vicinal residues showed a temperature optimum between 75 and 80 °C compared to 65 and 70 °C of the wild‐type enzyme. The variant caused a weight loss of PET films of 25.0 ± 0.8% (TfCut2: 0.3 ± 0.1%) at 70 °C after a reaction time of 48 h. The results demonstrate that a highly efficient and calcium‐independent thermostable polyester hydrolase can be obtained by replacing its calcium binding site with a disulfide bridge.

Engineered bacterial polyester hydrolases efficiently degrade polyethylene terephthalate due to relieved product inhibition.

Recent studies on the enzymatic degradation of synthetic polyesters have shown the potential of polyester hydrolases from thermophilic actinomycetes for modifying or degrading polyethylene terephthalate (PET). TfCut2 from Thermobifida fusca KW3 and LC-cutinase (LCC) isolated from a compost metagenome are remarkably active polyester hydrolases with high sequence and structural similarity. Both enzymes exhibit an exposed active site in a substrate binding groove located at the protein surface. By exchanging selected amino acid residues of TfCut2 involved in substrate binding with those present in LCC, enzyme variants with increased PET hydrolytic activity at 65°C were obtained. The highest activity in hydrolyzing PET films and fibers were detected with the single variant G62A and the double variant G62A/I213S. Both variants caused a weight loss of PET films of more than 42% after 50 h of hydrolysis, corresponding to a 2.7-fold increase compared to the wild type enzyme. Kinetic analysis based on the released PET hydrolysis products confirmed the superior hydrolytic activity of G62A with a fourfold higher hydrolysis rate constant and a 1.5-fold lower substrate binding constant than those of the wild type enzyme. Mono-(2-hydroxyethyl) terephthalate is a strong inhibitor of TfCut2. A determination of the Rosetta binding energy suggested a reduced interaction of G62A with 2PET, a dimer of the PET monomer ethylene terephthalate. Indeed, G62A revealed a 5.5-fold lower binding constant to the inhibitor than the wild type enzyme indicating that its increased PET hydrolysis activity is the result of a relieved product inhibition by mono-(2-hydroxyethyl) terephthalate. Biotechnol. Bioeng. 2016;113: 1658-1665. © 2016 Wiley Periodicals, Inc.

Degradation of agricultural biodegradable plastics in the soil under laboratory conditions

Mulches, usually consisting of polyethylene films, are used in agriculture to improve production. The main drawback of using polyethylene is its extremely high stability. Removing it from the field is usually not feasible, and so wastes remain accumulating in the field and pollute the environment. As an alternative, five potentially biodegradable plastic films for mulching (maize thermoplastic starch–copolyester, cereal flour–copolyester, polylactic acid–copolyester, polyhydroxybutyrate, and potato thermoplastic starch–copolyester) were tested to evaluate their degradation in an agricultural soil. Polyethylene film was used as control. A soil burial test was carried out during 6 months under laboratory conditions and film weight loss, chemical changes and soil microbial activity were monitored. Weight loss was fastest for the polyhydroxybutyrate film, followed by potato thermoplastic starch–copolyester and cereal flour–copolyester. Maize thermoplastic starch–copolyester and polylactic acid–copolyester required 5–6 months to disintegrate. Concomitant to the weight loss, chemical changes in the films and an increase in soil microbial activity were noticed. From the disintegration and biodegradation results of the biodegradable tested films, it is concluded that these films are an alternative for avoiding the soil pollution drawbacks of the polyethylene mulching films.

Sorption Kinetics of Pro-Oxidant-Loaded PE Plastic Bags in Aqueous Media

Sorption studies in aqueous media of pro-oxidant-loaded polyethylene (PE) films from commercial plastic bags are conducted. A total of 6 types of plastic bags are tested at three levels of thickness and two levels of color (transparent and opaque white). PE films are immersed in deionized water, acidic, and alkaline solutions at 60 °C. Sorption curves show that once the maximum uptake is reached, the weight change of PE films started to decline. The films showing the highest weight uptake and loss are observed in opaque films in alkaline solution. Analysis of variance (ANOVA) shows that during water immersion, both maximum weight uptake and loss are affected by colorant additive, with opaque films yielding the highest weight uptake and loss. During acid immersion, transparent films have significantly higher weight uptake than opaque films. The weight uptake during acid immersion is only affected by film thickness, with the thickest films showing the lowest weight uptake. Similar to results in water immersion, thickness is found to be insignificant to weight uptake and loss of PE films during alkali immersion. Meanwhile, colorant additive is significant to both weight uptake and loss for all films immersed in different solutions.