• Fibers and Polymers
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• 제4권4호
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• pp.182-187
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• 2003

Low molecular weight copolymers of maleic anhydride and vinyl acetate were prepared to develop formaldehyde free cross-linking agents. Since lower molecular weight is favorable for efficient penetration of the finishing agent into the cotton fibers in the padding process, the concentration of the initiator, chain transfer agent and the monomer ratios were varied to obtain copolymers of low molecular weights. The prepared polymers were characterized by GPC, $^1{H-NMR}$, FTIR, DSC and TGA. Copolymers of molecular weights of 2 000 to 10 000 were obtained and it was found that the most efficient method of controlling the molecular weight was by varying the monomer ratios. Poly(maleic anhydride-co-vinyl acetate) did not dissolve in water, but the maleic anhydride residue hydrolyzed within a few minutes to form poly(maleic acid-co-vinyl acetate) and dissolved in water. However, the maleic acid units undergo dehydration to form anhydride groups on heating above ${160}^{\circ}C$ to some extent even in the absence of catalysts. The possibility of using the copolymers as durable press finishing agent for cotton fabric was investigated. Lower molecular weight poly(maleic anhydride-co-vinyl acetate) copolymers were more efficient in introducing crease resistance, which appears to be due to the more efficient penetration of the cross-linking agent into cotton fabrics. The wrinkle recovery angles of cotton fabrics treated with poly(maleic anhydride-co-vinyl acetate) copolymers were slightly lower than those treated with DMDHEU and were higher when higher curing temperatures or higher concentrations of copolymer were used, and when catalyst, $NaH_2$$PO_2$, was added. The strength retention of the poly(maleic anhydride-co-vinyl acetate) treated cotton fabrics was excellent.

• 접착 및 계면
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• 제12권1호
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• pp.1-10
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• 2011

자동화된 반응 열량계를 이용하여 중합비율을 관찰하면서 blockiness가 다른 PVOH를 이용하여 VAE 에멀젼을 합성하였다. 입자 분포도를 관찰 결과 단량체와 물과 비율에 따른 일정한 그라프트율은 없었다. 초기 단량체-물의 비율이 낮은 곳에서 겔 효과가 관찰되었다. 또한 입자 분포는 넓고 이중 피크가 관찰되었다. 지속적으로 제한적으로 응징집되면서 입자성장이 이루어지는 것이 관찰되었다. 이것은 제한적인 응집현상과 사슬이 PVOH로 그라프팅되어 발생한 결과로 판단된다.

• 한국인쇄학회지
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• 제18권1호
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• pp.113-120
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• 2000

A previous paper was reported in being sensetized photopolymer, poly(vinyl cinnamoyl acetate) (PVCiA)1) with some squarylium dyes such as 1,3-bis(4 or 6-trifluouomethy1-1,3,3-trimethylindo) squarylium dyes(TFSQ). Here, we synthesized new 1,3-bis(4 or 6-nitro-1,3,3-trimethylindo) squarylium dyes(NISQ) to sensetize photopolymer, such as poly(vinyl cinnamoyl acetate). Absorption's coefficient of (NISQ8) is 8.5x105, the sensitivity of PVCiA added with NISQ8(3%) was highly sensitized 8 times than not added, and 2 times than TFSQ8(3%). Maybe, high absorption'scoefficient and red shift of NISQs with strongly withdrawing group to TFSQs afford to the high sensitivity of PVCiA.

• 폴리머
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• 제32권2호
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• pp.95-102
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• 2008

The $\alpha$,$omega$-diacrylate poly(dimethylsiloxane) (DA-PDMS) containing vinyl ester of versatic acid/vinyl acetate (Veova-10/VAc) was prepared by emulsion copolymerization of (DA-PDMS), Veova-10 (with VAc), and auxiliary agents at $85^{\circ}C$ in the presence of ammonium peroxodisulfate (APS) as an initiator. Sodium dodecyl sulfate (SDS) and nonylphenol ethylene oxide-40 units (NP-40) were used as anionic and nonionic emulsifiers, respectively. The resulting copolymers were characterized by using Fourier transform infrared spectroscopy (FT-IR). Thermal properties of the copolymers were studied by using thermogravimetric analysis(TGA) and differential scanning calorimetry (DSC). The morphology of copolymers was also investigated by scanning electron microscopy (SEM) and then the effects of variables such as temperature, agitation speed, surfactant kinds, molecular weights, initiator, and DA-PDMS concentrations on the properties of the silicone-containing Veova-10/VAc emulsions were examined. The calculation of monomer conversion versus time histories indicates that by increasing the DA-PDMS concentration the polymerization rate and the number of polymer particles decrease, respectively.

• 공업화학
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• 제10권3호
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• pp.362-366
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• 1999

Poly(vinyl chloride) (PYC) 유도제들로부터 용매증발법을 이용하여 바이오센서용 막을 제조하고 기체 투과특성을 조사하였다. 진공하에서 용매를 증발시켜서 제조된 막보다 공기 중에서 서서히 증발시켜 제조된 막의 투과도 계수가 더 높은 것으로 나타났다. PVC 유도체 막들에 대한 $CO_2$와 $O_2$의 투과도 계수는 공급부의 압력이 증가함에 따라 감소하였다. Carboxylated poly(vinyl chloride) (CPVC) 에 대한 dioctyl phthalate (DOP)의 첨가량이 증가함에 따라 투과도 계수는 증가하였다. 예를 들면 DOP 30 wt. %를 첨가하였을 때, $CO_2$와 $O_2$의 투과도 계수는 100 psig에서 각각 2.03, 0.96 Barrer 이었으며, DOP를 첨가하지 않았을 때 보다 약 4~5배 증가하였다. Poly(vinyl chloride-co-vinyl acetate) (PVCA)를 가수분해함으로써 OH기가 도입된 poly(vinyl chloride-co-vinyl acetate-co-vinyl alcohoI) (Syn-PVCAcAl)에 DOP를 첨가하였을 때 $CO_2$의 투과도 계수에서 시판제품 PVCAcAl보다 비교적 높은 값을 나타내었으나, $O_2$의 투과도 계수에는 차이가 없었다.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2000년도 봄 한국섬유공학회 학술발표회 논문집(Proceedings of the Korean Textile Conference)
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• pp.265-269
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• 2000

• Bulletin of the Korean Chemical Society
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• 제22권10호
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• pp.1136-1140
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• 2001

• 한국인쇄학회지
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• 제16권3호
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• pp.1-13
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• 1998

Some photopolymer, poly(vinyl cinnamoyl acetate)(PVCiA) was synthesized by esterification of polymer(vinyl alcohol(PVA) with monochloroacetic acid, followed by reaction poly(vinyl monochloroacetate)(PVChA) and potassium cinnamate. When esterification of PVA with monochloroacetic acid was reacted in the dimethyl sulfoxide(DMSO), in the synthesis of PVChA, it is very good yield and the successive cinnamoyl acetoxyl esterification of PVCiA can be successfully synthesized. But PVCiA is low photosensitive polymer if not added photosensitizing dyes. Here, we synthesized photosensitizing dyes. trifluoromethylindol squarylium dye derivatives(TFSQ). Indolization of 3-trifluoromethylphenyl-hydrazine formed 4- and 6-substituted indoles, the rate of 4- and 6-substituted indoles is close to unity. Absorption's coefficient of 1,3-bis(4-trifluoromethyl-1,3,3-trimethylindol) squarylium dye(TFSQ) is 7.57$\times$10\ulcorner, PVCiA added with TFSQ(3%) was highly sensitized six times than not added.

• 청정기술
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• 제12권4호
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• pp.191-197
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• 2006

초임계이산화탄소 내에서의 고분자중합은 생성된 고분자와 미반응물질의 분리가 용이하며, 유기용매나 물을 매체로 사용하는 기존의 고분자합성법에서와는 달리 무독성의 $CO_2$를 사용함으로써 폐수나 공해를 발생시키지 않는 청정공정으로 주목받고 있다. 본 연구에서는 산업적으로 다양한 용도를 가지고 있는 폴리비닐알코올(poly(vinyl alcohol) 또는 PVA)의 제조에 필수적으로 요구되는 폴리비닐아세테이트(poly(vinyl acetate) 또는 PVAc)를 초임계이산화탄소를 용매로 사용하여 세계에서 두 번째로 합성하였다. Silicone계 고분자 계면활성제와 3 가지 개시제를 이용하여 338.15 K와 34.5 MPa에서 vinyl acetate의 분산중합을 실시하고, 개시제와 계면활성제의 함량변화 및 종류에 따라 생성되는 PVAc의 수율과 분자량 변화, 반응시간이 PVAc의 수율과 분자량에 영향을 알아보았다. 반응실험 결과로 얻어진 PVAc의 Mw는 60,000 ~ 140,000 g/mol, Mn은 30,000 ~ 70,000 g/mol이며, 수율은 10 ~ 80%를 기록하였다.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 봄 학술발표회 논문집
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• pp.319-320
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• 2003

압전성과 초전성을 나타내는 고분자인 poly(vinylidene fluoride)(PVDF)는 poly(methyl methacrylate), poly(vinyl acetate), 및 Poly(vinyl methyl ketone)(PVMK) 등과 블렌딩하면 혼화성(miscibility)이 있다. 이들 블렌드물들을 용융온도 이상으로 승온시키면 낮은 온도에서는 균일상으로 존재하지만, 온도가 계속 증가하면 상분리되어 LCST(lower critical solution temperature)를 나타낸다[1]. 이러한 승온에 의한 상분리 거동에서 외부전장을 가하면 전기활성 고분자인 PVDF에 영향을 주어 상분리 거동이 변화될 것으로 예산된다. (중략)