• Elastomers and Composites
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• 제51권2호
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• pp.154-160
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• 2016

The four different vinyl monomers in the reaction of isocyanate-terminated polyurethane prepolymer were used for the preparation of macromonomers and successfully employed in the dispersion polymerization of styrene. The chemical structures of vinyl monomer in macromonomers influenced on the polystyrene particle characteristics, such as the conversion, weight average molecular weights ($M_w$), polydispersity index (PDI), weight average diameter ($D_w$), and uniformity. The conversion of polystyrene increased with amounts of methyl group in vinyl monomer. Also the uniformity of polystyrene particles increased with amounts of methyl group in vinyl monomer.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.153-154
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• 2006

The development of metal catalysts that can polymerize or copolymerize "polar" $Ch_2=CHX$ monomers by insertion mechanisms would significantly expand the scope of metal-catalyzed polymerization and enable the synthesis of new materials with enhanced properties. We have studied the reactions of single-site olefin polymerization catalysts with vinyl chloride, acrylonitrile, and vinyl ethers, in order to probe monomer coordination trends, insertion rates and regioselectivity, and the structures and reactivity of metal alkyls that contain functional groups on the alpha and beta positions of the alkyl chain. These studies provide insights to the key issues that underlie the "polar monomer" problem. Copolymerization of olefins and selected vinyl ethers has been achieved.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.323-323
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• 2006

Multi-vinyl monomer, which contains many vinyl groups in a molecule, was prepared by esterification of hydroxyl groups of poly(2-hydroxyethyl methacrylate) with methacryloyl chloride. Then, copper-mediated atom transfer radical polymerization was carried out as a template polymerization. The propagation of polymerization was investigated by kinetic analysis.

• Macromolecular Research
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• 제12권4호
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• pp.325-335
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• 2004

Molecular weight distributions of poly(vinyl neo-decanoate) produced by the bulk polymerization of the monomer to low conversions were investigated to obtain values of the rate constants for the chain transfer to monomer ( $C_{M}$). The value of $C_{M}$ of 7.5($\pm$0.6)${\times}$10$^{-4}$ was obtained from a logarithmic plot of the number distribution at 5,25, and 5$0^{\circ}C$, which suggests that the activation energy for chain transfer is on the order of 20-25 kJ ㏖$^{-1}$ . These plots were linear between the number and weight-average degrees of polymerization, but not over the whole molecular weight range for which a significant signal was observed in the gel permeation chromatography (GPC) trace. Modeling suggests that the deviations observed at high molecular weights can be explained by branching of the chains through chain transfer to the polymer, with a branching density as low as 10$^{-5}$ , without affecting the slope at low values of the number of monomer unit, N. This deviation from the expected distribution of linear chains was used to estimate the branching densities at low conversion.ion.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 The Korea-Japan Joint Symposium
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• pp.1-2
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• 2003

Some new synthetic routes for the preparation of poly (isobutyl vinyl ether) (P(IBVE)) having a controllable molar mass with narrow distribution via catalytic or photoinduced living cationic polymerization and their conversion to corresponding PVA have been developed. It was found that the combination of iodomethyl methyl ether (IMME)-zinc iodide is effective in the initiation of the catalytic and the various combinations of diphenyliodonium halides, well known photocationic initiators (DPIX) with zinc halides (ZnX$_2$) are also useful in photoinduced living cationic polymerization of isobutyl vinyl ether (IBVE). Polymerization both in the catalytic and photoinduced systems precede until the full consumption of the monomer and the rate of polymerization increases as the concentration of the catalyst or photoinitiator. The number average molar mass of the resulting polymer is proportional with % conversion, which is determined by the ratio of monomer consumed and the initial values of the catalyst or initiator. The living nature was also confirmed by subsequent monomer addition technique.

• 폴리머
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• 제35권5호
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• pp.409-418
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• 2011

A novel silicone (Si) containing vinylic monomer, N-(3-(triethoxysilyl)propyl) methacrylamide (TESPMA), based on 3-aminopropyltriethoxysilane (APTES) and methacryloyl chloride (MCl) has been synthesized for formulation of waterborne polyurethane (WPU). Two types of vinyl group containing Si, methacryloxypropyltriethoxysilane (MPTES) and triethoxyvinylsilane (TEVS), have been used as coupling reagents for comparison of the effects of Si kinds with TESPMA on the WPU. A series of new siliconized WPU, vinyl acetate/vinyl ester of versatic acid (VAc-Veova), TESPMA, MPTES and TEVS hybrid latexes have been successfully prepared by emulsion polymerization in the presence of WPU dispersion.

• 한국응용과학기술학회지
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• 제13권2호
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• pp.77-84
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• 1996

Poly(vinyl acetate)와 poly(vinyl acetate-co-2-ethylhexyl acrylate)를 여러 조건에서 semicontinuous emulsion 중합으로 합성하였다. Overall conversion, emulsion 입자크기, pH, 점도 등을 합성한 두 emulsion polymer에 대해 측정하였다. Vinyl acetate monomer에 2-ethylhexyl acrylate를 도입함으로서 emulsion 입도, 점도, 중합 속도, 유리 전이 속도가 감소함을 확인하였다.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1998년도 봄 학술발표회 논문집
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• pp.130-134
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• 1998

The physical properties of poly(vinyl alcohol) (PVA) are highly dependent on the degree of syndiotacticity, which is determined primarily by the choice of the vinyl ester monomer precursor. Efforts to produce more syndiotactic PVAs, as well to increase the molecular weight, have centered on the polymerization of vinyl trifluoroacetate,$^1$ vinyl trichloroacetate,$^2$ and vinyl pivalate (VPi).(omitted)

• Macromolecular Research
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• 제17권12호
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• pp.1003-1009
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• 2009

Copolymers of N-vinylpyrrolidone (NVP) comonomer with styrene (St), hydroxypropyl methacrylate (HPMA) and carboxyphenyl maleimide (CPMI) were synthesized by free radical polymerization using 2,2'-azobisisobutyronitrile (AIBN) initiator in 1,4-dioxane solvent. The copolymers formed were characterized by FTIR, $^1H$ NMR and $^{13}C$ NMR techniques and their thermal properties were studied by DSC and TGA. Copolymer composition was determined by $^1H$ NMR and/or by elemental analysis and monomer reactivity ratios (MRR) were estimated by the linear methods of Kelen-Tudos (K-T) and extended Kelen-Tudos (EK-T) and the non-linear approach. Copolymers of St and HPMA with NVP formed blocks of one of the monomer units, whereas alternating copolymers were obtained in CPMI-NVP, depending upon the side chain substitution. The MRR values are discussed in terms of monomer structural properties such as electronegativity and electron delocalization. The sequence distribution of monomers in the copolymers was studied by statistical method based on the average reactivity ratios obtained by EK-T method.

• 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.