• Applied Chemistry for Engineering
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• v.9 no.7
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• pp.1053-1058
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• 1998

Poly(vinyl butyral)s (PVB) with different butyral content were synthesized from poly(vinyl alcohol)(PVA) and n-butylaldehyde with acid catalyst. Bound butyral unit in PVB was determined by elemental analysis. Synthesized PVBs were reacted with p-azidobenzaldehyde to give photosensitive polymer with azidobenzene group(PVB-AZ). Bound photosensitive azidobenzene group in PVB-AZ was determined by UV spectrophotometry. The photosensitivity of PVB-AZ was compared with that of PVB/2,6-bis(p-azidobenzylidene)cyclohexanone(BAC) photosensitizer mixture system by gray scale method. Photosensitivity of PVB-AZ was higher than that of PVB/BAC mixture system. The photosensitivity of PVB-AZ was dependent on the developer used due to the solubility of PVB-AZ in a developer solvent.

• Korean Membrane Journal
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• v.6 no.1
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• pp.61-69
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• 2004

Small angle light scattering (SALS) and field emission scanning electron microscope (FE-SEM) have been used to investigate the effects of alcohol on phase separation of chlorinated poly(vinyl chloride) (CPVC)/tetrahydrofuran (THF)/alcohol (9/61/30 wt%) solution during water vapor induced phase separation. A typical scattering pattern of nucleation & growth (NG) was observed for all casting solutions of CPVC/THF/alcohol. In the case of the phase separation of CPVC dope solution containing 30 wt% ethanol or n-propanol, the demixing with NG was observed to be heterogeneous. Meanwhile, the phase separation of CPVC dope solution with 30 wt% n-butanol was found to be predominantly homogeneous NG. Although the different phase separation behavior of NG was observed with types of alcohol additives, the resultant surface morphology had no remarkable differences. That is, even though the NG process by water vapor is either homogeneous or heterogeneous, this difference does not play a main role on the final surface morphology. However, it was estimated from the result of hydraulic flux that the phase separation by homogeneous NG provided the membrane geometry with lower resistance in comparison with that by heterogeneous one.

• Proceedings of the Korean Fiber Society Conference
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• 1995.10a
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• pp.120-121
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• 1995

• Proceedings of the Korean Fiber Society Conference
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• 1995.10a
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• pp.119-119
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• 1995

• Journal of Adhesion and Interface
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• v.13 no.2
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• pp.64-72
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• 2012

Vinyl acetate/alkyl acrylate copolymers were prepared by water-born emulsion copolymerization according to the compositional change of vinyl acetate and various alkyl acrylates such as methyl acrylate (MA), ethyl acrylate (EA), and n-butyl acrylate (BA). Ammonium persulfate (APS) was used as an initiator and poly(vinyl alcohol) (PVA) was used as a protective colloid. The significant result was described as follows. The activation energy determined by an isothermal analysis in the temperature region between $100{\sim}200^{\circ}C$ of the copolymer had the order of PVAc/PMA > PVAc/PEA > PVAc/PBA. The peel strengths before and after the plasma treatment were the order of PVAc/PMA > PVAc/PEA > PVAc/PBA.

• Clean Technology
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• v.12 no.4
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• pp.191-197
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• 2006

Polymerization in supercritical carbon dioxide has been getting attention since it is easier to separate the remaining reactants from product polymer and since it is a cleaner process that produces neither wastewater nor air pollutants, compared to the conventional polymerization processes. In this study, poly(vinyl acetate) (PVAc) that is necessary in producing poly(vinyl alcohol) (PVA) with a lot of industrial applications was manufactured in the presence of supercritical carbon dioxide for the second time in the world. A poly(dimethylsiloxane)(PDMS)-derivative surfactant and three initiators were employed in the polymerization of vinyl acetate (VAc) at 338.15 K and 34.5 MPa. Investigation was carried out to find out the effect of the amounts and types of initiators and surfactants as well as the effect of reaction time on the yield and the molecular weight of PVAc. The weight average molecular weight (Mw) of PVAc was in the range of 60,000 ~ 140,000 g/mol, and the number average molecular weight was in the range of 30,000 ~ 70,000 g/mol. The yield of PVAc was spread over 10 ~ 80%, based on the amount of VAc monomer.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.173-176
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• 2003

Poly(vinyl alcohol)(PVA)는 친수성이 좋고, 제조가 용이하며, 화학 약품에 대한 내성이 강한 특성을 가지고 있어, 코팅제나 페인트, 접착제 등 산업 전반에 널리 사용되고 있으며 섬유 제조에 대해서도 최근 활발하게 연구되고 있다. 전기방사(Electrospinning)는 전기장 내의 전위차를 이용하여 sub-micron 또는 nano-scale의 직경을 가지는 초극세 섬유를 제조할 수 있는 유용한 방법이다. (중략)

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.414-416
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• 2002

폴리비닐알코올 (poly(vinyl alcohol), PVA)는 분해되어 대부분의 성분이 물과 이산화탄소로 전환되는 가장 이상적인 환경친화성 고분자이다. PVA만의 특유한 반응인 비누화 과정에 의해 가지가 모두 제거되기 때문에 화학적인 방법에 의해 완벽한 선형고분자를 얻는 것이 가능하다. PVA는 측쇄에 존재하는 히드록시기의 강력한 수소결합 때문에 우수한 반응성 및 결합성을 보유한 유기 고분자로서, 수용성 뿐 아니라 다양한 소재와 상용성이 있는 것으로 알려져 있다(1-4). (중략)

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.215-218
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• 2002

Poly(vinyl alcohol)(PVA)는 1924년 W. O. Herrmann과 W. Haehnel이 Poly(vinyl esters)를 caustic soda 용액에서 비누화하여 합성한 뒤 많은 연구 및 사용되어지고 있는 고분자이다. 환경친화적이고, 인체에 무해하여 인공관절, 콘택트 렌즈 등에 이용이 되고 있다. 특히 구조가 선형적이고 zig-zag구조를 가지기 때문에 고강도, 고탄성을 갖는 섬유의 제조가 가능한 소재이다[1]. PVA섬유의 제조는 용매를 이용한 습식방사 및 겔방사로 섬유를 제조한다. (중략)

• Proceedings of the Membrane Society of Korea Conference
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• 1993.10a
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• pp.46-51
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• 1993

Poly(vinyl chloride) was modified by reacting with sodium N-methyldithiocarbamate or N-methyl-N-carboxymethyldithiocarbamate to obtain crosslinked dithiocarbamated PVC(PMD, PSDC). In addition PSDC were substituted with metal ions of $Ma^+, Li^+$ and $Cs^+$. PLMD and PSDC were reacted with copper ions in alcohol or aqueous solution to produce chelate complexes of dithiocarbanated PVC, respectively(PMD-$Cu^{2+}$, PSDC-$Cu^{2+}$). PSDC was irradiated by ultraviolet light to enhance crosslinking(PSDC-UV).