• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.1583-1584
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• 2011

• Journal of the Korean Chemical Society
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• v.23 no.5
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• pp.329-337
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• 1979

The water-vapour transmission ratios (WVTR) of the various commercial polymer films have been investigated at the constant pressure and relative humidity (RH). Water proofnesses, the reciprocals of WVTR for the various samples, were determined using a cup device and maintaining the sample films at a constant temperature ($40{\pm}1^{\circ}C$) and a constant R. H ($90{\pm}2%$) for 24 hours. The following order of the relative proofness was observed; oriented polypropyrene (O.PP) > high density polyethylene (HDPE, Inflation) > high density polyethylene (HDPE. T-die) > casted polypropylene (C. PP) > nonoriented polyester (N. PET) > low density polyethylene (LDPE) > oriented polyester (O. PET) > rigid polyvinyl chloride (Rigid PVC) > semirigid polyvinyl chloride (Semirigid PVC) > nonrigid polyvinyl chloride (Nonrigid PVC) > oriented nylon (O. Nylon) > nonoriented nylon (N. Nylon). And water proofness order was also observed to decrease with the temperature rising; HDPE (T-die) > C. PP > O. PET > LDPE > O. Nylon. The activation energies of LDPE, HDPE (T-die), C. PP, O. PET and O.Nylon films were 12.0, 11.1, 11.4, 11.7, 14.1 kcal/mole, respectively. The WVTR's of the films were increased with the polarity of polymer and the addition of plasticizer in PVC, decreased with the increase of the film thickness and mechanical orientation. The WVTR's of the laminated films O. PP/LDPE, N.Nylon/LDPE, C.PP/LDPE were also more dependent on the film thickness than the WVTR's of the single films.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.8 no.4
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• pp.213-216
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• 1975

Yellow sea bream contains comparatively larger amount of fat among white muscle fishes, so that rancidity might easily occur during drying and storage. For the purpose of the protection of rancidity, the effect of some antioxidants was studied when yellow sea bream was sun-dried after dipping in the solutions and packed in PVC film$0.3mm\times12cm\times30cm $ for storage at room temperature. The inhibitory effect of additives was in order of Tenox-II, BHA, Sustane and NDGA, while EDTA, potassium sorbate, CTC and $\alpha-naphthylamine$ were ineffective. The results suggest that the treatment of $0.1\%$ Tenox-II solution and packing in PVC film is better condition to improve the quality of product and during drying and storage.

• Korean Membrane Journal
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• v.11 no.1
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• pp.8-14
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• 2009

The sulfonated poly(styrene-divinylbenzene-acrylonitrile) (ST-DVB-AN) composite polymer electrolyte membrane based on the original PVC film was successfully synthesized to improve oxidative stability using semi-interpenetrated polymer network (semi-IPN). Weight gain ratio after copolymerization was enhanced by the DVB and AN contents, and the sulfonated membranes were characterized in terms of proton conductivity (k), ion exchange capacity (IEC), and water uptake ($W_U$). The effect of DVB content and AN addition were thoroughly investigated by comparing the resulted properties including oxidative stability. The obtained ST-DVB-AN composited semi-IPN membranes showed relatively high proton conductivity and IEC compared with Nafion117, and greatly improved oxidative stability of the synthesized membrane was obtained. This study demonstrated that a semi-interpenetrated sulfonated ST-DVB-AN composited membrane reinforced by PVC polymer network is a promising candidate as an inexpensive polymer electrolyte membrane for fuel cell applications.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.154-158
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• 2001

The heat treatment of PVC film containing PVC 65%, DOP(Dioctyl Phthalate) 32% as plasticizer, Ca-Zn stearates and surface agent was peformed under several conditions to study the degradation behavior of PVC sheet. In the case of H$_2$SO$_4$, the dehydrochlorination was ca.100% at 25$0^{\circ}C$ for 3h. The char involving the smaller pores was produced with hydrothermal treatment. The pore size became small with increasing the treatment time and temperature. In the case of treatment with Ca(OH)$_2$, the sizes of pores produced in char were about sever ~ 10${\mu}{\textrm}{m}$ at 2$25^{\circ}C$ for 12h. In the case of H$_2$SO$_4$, the size of pores were about 1${\mu}{\textrm}{m}$ in 5M H$_2$SO$_4$for 12h.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.746-750
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• 2001

The heat treatment of PVC film containing PVC 65%, DOP(Dioctyl Phthalate) 32% as plasticizer, Ca-Zn stearates and surface agent was peformed under several conditions to study the degradation behavior of PVC sheet. In the case of H$_2$SO$_4$, the dehydrochlorination was ca.100% at 25$0^{\circ}C$ for 3h. The char involving the smaller pores was produced with hydrothermal treatment. The pore size became small with increasing the treatment time and temperature. In the case of treatment with Ca(OH)$_2$, the sizes of pores produced in char were about sever ~ 10${\mu}{\textrm}{m}$ at 2$25^{\circ}C$ for 12h. In the case of H$_2$SO$_4$, the size of pores were about l${\mu}{\textrm}{m}$ in 5M H$_2$SO$_4$for 12h.

• Analytical Science and Technology
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• v.13 no.5
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• pp.683-692
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• 2000

The volatile organic compounds emitted from food wrapping films when it was used at high temperatures. However, the testing method based on solvent extraction may not be suitable for determination of volatile organic compounds from food wrapping films. Therefore, thermal extraction device was investigated in the study for reflection of actual usage conditions at home and restaurant. In this study, PVC food wrapping films were exposed to normal use condition controlled from $50^{\circ}C$ to $120^{\circ}C$ and collected on sorbent trap. Then, emitted VOCs from the films were analyzed with On-column cryofocusing-GC/MS system. The major VOCs emitted from films were $C_{12}-C_{18}$ paraffinic hydrocarbons, dimethylphthalate, alkylphenols, known as endocrine disrupting chemical, such as tetramethylbutylphenol, tert-butylphenol, and nonylphenol. The concentration of tetramethylbutylphenol emitted from PVC films was $0.07ng/cm^2$ at $50^{\circ}C$, rapidly increased with temperature, $3.94ng/cm^2$ at $100^{\circ}C$.

• Food Science and Preservation
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• v.4 no.2
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• pp.139-146
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• 1997

The influence of packaging methods(0.03mmPE, 0.05mmPE, 0.1mmPVC, VACUUM) and marketing temperatures(2$0^{\circ}C$, 1$0^{\circ}C$) on the shelf-life and quality were investigated in yam(Dioscorea). Respiration, weight-loss and rotting-rate was reduced in polyethylene film packaging in the order of VACUUM, 0.1mmPVC, 0.05mmPE, 0.03mmPE and the effect was more outstanding at 1$0^{\circ}C$ than 2$0^{\circ}C$. The ethylene concentration of PVC packaging group was higher than that of other packaging methods, which was related with sprouting. firmness was higher in low-temperature than in room-temperature. PPO activity was lower in vacuum than in other packaging methods, which was associated with browning. The shelf-life of yam was the longest in vacuum Packaging, 3 weeks at 2$0^{\circ}C$ and more than 4 weeks at 1$0^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.969-976
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• 2002

The migrating level of di-(2-ethylhexyl) adipate (DEHA) in PVC wrap to various foodstuffs dishes was determined using acetone/n-hexane as an extracting solvent. The recovery ratio of DEHA from various foodstuffs ranged from 81.3 to 91.2%. During storage at $10\;or\;20^{\circ}C$ for up to 3 days, highest migration of 22.9 mg/kg occurred with pork belly, an indication that increases in fat content, storage temperature, and storage time result in increasing DEHA migration. DEHA concentrations of various delivered dishes ranged between 6.9 and 29.8 mg/kg, and highest migration was observed in Chambbong, which had the highest fat content among samples. After microwave-reheating, which resulted in a tight contact between film and food samples, DEHA was not detected in rice and potato, whereas up to 158.8 mg/kg was detected in pizza. When the wrap film was not contacted with the surface of food, the migration was lowered. Migration levels of DEHA from PVC wrap film into samples under various exposure conditions often exceeded the limit value of $3\;mg/dm^2\;and/or\;18\;mg/kg$ set by the European Union.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.29 no.2
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• pp.119-128
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• 2023

This study was examined for investigating the quality changes of spring kimchi cabbage under various treatments (pre-drying/pre-cooling, packaging types, and stacking and loading in container and pallete in the storage room) during cold storage. The results showed that control (upward stacking without pre-drying/pre-cooling and HDPE or PVC film cover) was increased significantly in weight loss and trimming loss, compared to other treatments such as DPDH (downard stacking + pre-drying + HDPE), DPDP (downard stacking + pre-drying + PVC), DPCH (downnard stacking + pre-cooling + HDPE), and UPCH (upward stacking + pre-cooling +HDPE) during storage for three months. In Sensory evaluation, judging from marketable properties, the desirable appearance of spring kimchi cabbage with the modified pallet-unit MA packed, PE, and PVC film wrapping could be maintained until 9 weeks after pre-drying/pre-cooling. Meanwhile, the control without any treatments after 6 weeks, the sensory score was declined, significantly. In general, the low temperature (10℃ and 2℃) of pre-treatment with combination of plastic film packaging in spring kimchi cabbage storage could inhibit the physiological activity and reduce the direct exposure of environmental cold air in the storage. Therefore, these two variables were the key points for extending the shelf-life of spring kimchi cabbage.