• Proceedings of the KIEE Conference
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• 1984.07a
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• pp.185-187
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• 1984

• Applied Chemistry for Engineering
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• v.33 no.4
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• pp.367-372
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• 2022

The effect of the addition of a polyvinylchloride (PVC) non-solvent to a PVC-tetrahydrofuran (THF) solution on the surface properties of the PVC thin film was analyzed. The non-solvents used were composed of alcohol-based and non-alcoholic ones. Surface morphologies of PVC thin films according to the addition of the non-solvent were compared. In addition, the hydrophobic properties relying on the surface characteristics were compared. The micro-bubbles generated in the preparation of PVC-THF solution affected the surface morphology of the thin film. In order to implement the normal surface physical properties of the coating thin film at the relatively high concentration of PVC-THF solution, the selection of appropriate drying method was required. When an alcohol-based non-solvent was added, a PVC thin film having a granular porous surface was obtained and exhibited super hydrophobic properties. The volume ratio of the PVC-THF solution to the non-solvent affects the surface shape of the coating thin film. The larger the amount of non-solvent was added, the more advantageous it was to form a super hydrophobic PVC thin film.

• Membrane Journal
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• v.21 no.2
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• pp.193-200
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• 2011

An amphiphilic graft copolymer comprising a poly(vinyl chloride) (PVC) backbone and poly (styrene sulfonic acid) (PSSA) side chains (PVC-g-PSSA) was synthesized via atom transfer radical polymerization (ATRP). Mesoporous titanium dioxide $(TiO_2)$ films with crystalline anatase phase were synthesized via a sol-gel process by templating PVC-g-PSSA graft copolymer. Titanium isopropoxide (TTIP), a $TiO_2$ precursor was selectively incorporated into the hydrophilic PSSA domains of the graft copolymer and grew to form mesoporous $TiO_2$ films, as confirmed by scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. The performances of dye-sensitized solar cell (DSSC) were systematically investigated by varying spin coating times and the amounts of P25 nanoparticies. The energy conversion efficiency reached up to 2.7% at 100 mW/$cm^2$ upon using quasi-solid-state polymer electrolyte.

• Korean Journal of Environmental Agriculture
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• v.41 no.4
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• pp.276-281
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• 2022

BACKGROUND: Plastics that are used in our daily lives largely end up in the environment. In agricultural environments, plastic wastes and microplastics can be found due to the uses and improper management of plastic products (e.g., vinyl greenhouses and mulching vinyl). Microplastics can also interact with contaminants in the agricultural environment. Therefore, this study was set to investigate the sorption characteristics of tetracycline, one of widely used antibiotics, on microplastics. METHODS AND RESULTS: The sorption tests were carried out with the tetracycline solutions (0-30 mg L^-1) and microplastic films prepared from low density polyethylene (LDPE) and polyvinyl chloride (PVC). The residual tetracycline concentrations were analyzed and fitted to the Freundlich and Langmuir isotherm models. The tetracycline sorption patterns on LDPE and PVC films were described better with the Freundlich isotherm model than the Langmuir isotherm model. The isotherm model parameters suggested that the maximum sorption amount of tetracyline was greater for PVC, while the sorption affinity was greater for LDPE. CONCLUSION(S): Different types of microplastics can have different sorption characteristics of tetracycline. Therefore, there is a need for continuous research on the interaction of various types and shapes of microplastics and contaminants in the environment.

• Applied Chemistry for Engineering
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• v.26 no.1
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• pp.35-39
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• 2015

Polyvinylchloride (PVC) thin films having a microporous structure could be prepared by using the solubility difference in solvents. PVC thin film with a water contact angle of $150^{\circ}$ or more was obtained from the PVC solution consisting of the mixture of tetrahydrofuran as a solvent and propanol as a non-solvent. In the drying process of dip-coated PVC film, the increase of drying temperature reduced the tendency of roughened surface, which led the decrease of surface hydrophobicity. As the addition of propanol in the solution with 1 wt% PVC increased, the uniformity of surface roughness was improved. In the case of oxygen plasma treatments, even though the surface structure of PVC thin film was not notably changed, the surface property of the film was changed from the super-hydrophobicity to hydrophilicity as a function of the plasma exposing time.

• Electrical & Electronic Materials
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• v.10 no.6
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• pp.576-580
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• 1997

In this paper, the viewing angle characteristics of amorphous (a) - twisted nematic (TN)-liquid crystal display (LCD) on poly(vinyl)cinnamate (PVC) surface with UV (ultraviolet) light irradiation were investigated. It was found that the threshold voltage increases with increasing the polymerization of PVC surfaces. We observed that the domain size of a-TN-LCD decreases with increasing the photo polymerization by increasing UV light irradiation time on PVC films. Also, we observed that the viewing angle of a-TN-LCD increased with increasing the photo polymerization on PVC surfaces. Finally, we consider that the viewing angle of a-TN-LCD on PVC surfaces is large compared to a-TN-LCD on polyimide (PI) surface.

• Applied Chemistry for Engineering
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• v.27 no.6
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• pp.627-632
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• 2016

Ethyl methacrylate (EMA) monomer coupling onto the polyvinylidene fluoride (PVDF) film surface was attempted to enhance the interfacial adhesive force between PVDF-polyvinyl chloride (PVC) bilayer films via dielectric barrier corona discharge. The interfacial forces were quite enhanced when PVDF films were treated by corona discharge in an EMA 1% atmosphere. The contact angle of PVDF films decreased due to corona treatment. X-ray photoelectron spectroscopy (XPS) analysis showed that the carbon and oxygen content of the PVDF film surface increased with corona discharge while the fluoride content decreased. The curve fitting of XPS $C_{1s}$ peaks revealed that the non-polar C-C bonded carbon and oxygen-bonded carbon increased gradually with corona treatment, while the fluorine-bonded carbon decreased.

• Polymer(Korea)
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• v.26 no.5
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• pp.559-567
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• 2002

Poly (vinyl chloride) was blended with blended with vinyl chloride-acrylonitrile copolymers (MO-01 : M$\sub$w/=199049, AN=22.79%, MO-02 : M$\sub$w/=238523, AN=47.03%, MO-03 : M$\sub$w/=289496, AN=52.49%, MO-04 : M$\sub$w/=341837, AN=58.68% by mixing dimethylformamide (DMF) solution of each polymer and their morphology, viscosity, viscoelastic and mechanical properties were studied. Blends of PVC and MO-01 showed a homogeneous morphology. On the contrary, the other copolymer blends showed a large phase separation with spherical domains. Miscibility of blends of PVC and MO-01 was shown to be better than that of blends of other copolymers from morphological and viscoelastic studies. Even though blends of PVC and MO-01 were observed to be the considerable compatibility at a composition of PVC/MO-01=90/10, the mechanical properties of blend films were not improved too much in most blend cases.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.04a
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• pp.120-122
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• 1997

In this paper, the viewing angle characteristics of amorphous (a) - twisted nematic (TN) - liquid crystal display (LCD) on poly(viny)cirmamate (PVC) alignment surfaces were investigated. It was found that the threshold voltage is increased with increasing the polymerization on PVC surfaces. We suggest that the threshold voltage is affected to the surface anchoring strength with increasing the polymerization of the alignment film. Also, we obtained that the viewing angle of a-TN-LCD is increased with increasing the polymerization on PVC surfaces. Finally, we considered that the viewing angle of a-TN-LCD on PVC surfaces is large compared to TN-LCD on rubbed polyimide (Pl) surface.

• Food Science and Preservation
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• v.15 no.6
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• pp.804-809
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• 2008

Modified atmosphere packaging (MAP) was assessed in terms of extending the shelf life of Solidago virgaurea spp. gigantea. In June 2005 Solidago virgaurea spp. gigantea were harvested from Ulleung Island, packaged in $30\;{\mu}m$ PP, $30\;{\mu}m$ Antifogging-OPP, $30\;{\mu}m$ LDPE, $18\;{\mu}m$ Macroperforated-HDPE, $60\;{\mu}m$ nylon/PE, or $85\;{\mu}m$ PVC/PE film, then stored at 4, 10 or $20^{\circ}C$ for up to 14 days. The $O_2$ concentration decreased to $9{\sim}10%$ in the PP and A-OPP packaging, to $12{\sim}16%$ in LDPE packaging, and to 2% in nylon/PE and PVC/PE packaging at $10^{\circ}C$. The $CO_2$ concentration increased to 5% at $10^{\circ}C$ in PP, A-OPP and LDPE packaging, but increased consistently in the nylon/PE and PVC/PE packaging. Weight loss was markedly reduced by all MAP films except M-HDPE, and which was enhanced with decreasing storage temperature. The soluble solids and pH were not affected by the packaging material at $4^{\circ}C$ and $10^{\circ}C$, but were affected at $20^{\circ}C$. The highest score for sensory qualities (appearance, color and overall acceptability) was obtained for vegetables stored at $4^{\circ}C$ in PP films. Our results show that MAP using PP films and $4^{\circ}C$ storage can effectively maintain the quality of Solidago virgaurea spp. gigantea.