• Journal of Integrative Natural Science
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• v.5 no.2
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• pp.127-130
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• 2012

Polymerization of vinyl monomers is promoted by thianthrene cation radical as a part of our research concerning the reactions of various agents with readily isolable, yet highly reactive species and elucidate the biological activity. Thianthrene cation radical initiated the homopolymerization and copolymerization of styrene and ethyl vinyl ether. The polymerization yields decreased as the concentration of phenylacetylene or diphenylethylene increased. Such polymereization by cationic thianthrene radical could provide some clues for the reaction in living animals. Comments on possible polymerization mechanisms were suggested.

• Macromolecular Research
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• v.17 no.12
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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.

• Bulletin of the Korean Chemical Society
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• v.18 no.3
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• pp.318-323
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• 1997

ο-(2-Vinyloxyethoxy)benzylidenemalononitrile (3a) and methyl ο-(2-vinyloxyethoxy)-benzylidenecyanoacetate (3b), m-(2-vinyloxyethoxy)benzylidenemalononitrile (4a), and methyl m-(2-vinyloxyethoxy)benzylidenecyanoacetate (4b) were prepared by the condensation of ο-(2-vinyloxyethoxy)benzaldehyde (1) and m-(2-vinyloxyethoxy)benzaldehyde (2) with malononitrile or methyl cyanoacetate, respectively. Bifunctional vinyl ether monomers 3a and 3b polymerized quantitatively with radical initiators in γ-butyrolactone solution at 65 ℃, while meta-isomers 4a and 4b gave lower yields of polymers under the same conditions. The polymers 5-6 obtained from the monomers 3-4 were insoluble in common solvents due to cross-linking. Under the same polymerization conditions ethyl vinyl ether polymerized well with model compounds ο-methoxybenzylidenemalononitrile 7a, methyl ο-methoxybenzylidenecyanoacetate 7b, m-methoxybenzylidenemalononitrile 8a, and methyl m-methoxybenzylidenecyanoacetate 8b, respectively, to give 1:1 alternating copolymers 9-10 in high yields. Cross-linked polymers 5-6 showed a thermal stability up to 300 ℃, and showed a double phase degradation pattern in their TGA thermograms. Polymers 5-6 showed broad endothermic bands around 75-110 ℃ without any characteristic Tg peaks in DSC thermograms. Alternating copolymers 9-10, except copolymer 9b were soluble in common organic solvents. The inherent viscosities of polymer 9-10 were in the range of 0.35-0.62 dL/g. Polymer films cast from acetone solution were cloudy and tough and Tg values obtained from DSC thermograms were in the range of 118-165 ℃.

• Journal of the Korean Professional Engineers Association
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• v.31 no.5
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• pp.44-48
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• 1998

• KSBB Journal
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• v.16 no.1
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• pp.82-86
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• 2001

Glyco-acrylate and methacrylate were synthesized by lipase-catalyzed glycosylation of acrylic acid, methacrylic acid and their vinyl esters with $\beta$-methyl fructoside and glycerol in t-butanol as a reaction medium. At the optimum conditions for enzymatic glycosylation of acrylic acid and vinyl methacrylate, we attained up to 80% conversion for glyco-acrylate from acrylic acid and 90% conversion for glyco-methacrylate from vinyl methacrylate. The polymerizable glyco-acrylates and methacrylate have biomedical application as hydrophilic monomers and hydration modifiers to be use for hydrogel contact lens formulation.

• Textile Coloration and Finishing
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• v.20 no.5
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• pp.28-34
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• 2008

PET fabrics were photografted under continuous UV irradiation with vinyl pyrrolidone (VP) and acryloylmorpholine(ACMO) as monomers and benzophenone as a hydrogen-abstractable photoinitiator. ACMO can be grafted onto the PET fabrics more efficiently than VP. The grafted PET surfaces were characterized by ATR, ESCA, SEM and zeta potential measurement. ATR and ESCA analysis indicated significant alterations on chemical structure and atomic composition on the surface of the grafted fabrics, where nitrogen content increased with increasing grafting yield. SEM images showed that the fabric surface was covered with the grafted polymers. The zeta potentials and the water wettability of the grafted PET increased with grafting. Also the photografted fabrics showed an increased dyeablity to reactive dyes and increased affinity to various iodine species which imparted anti-bacterial properties.

• Bulletin of the Korean Chemical Society
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• v.14 no.6
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• pp.651-652
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• 1993

• Proceedings of the Korean Fiber Society Conference
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• 2007.11a
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• pp.35-37
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• 2007

• Journal of the Korean Applied Science and Technology
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• v.21 no.1
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• pp.37-44
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• 2004

Glycosyl acrylate and methacrylate were synthesized by lipase-catalyzed esterification of vinyl acrylate and vinyl methacrylate with ${\beta}$-methyl glucoside in t-butanol as a reaction medium. At the optimum conditions of initial concentration of 150g/l ${\beta}$-methyl glucoside, molar ratio of 1 : 3, 5%(w/v) lipase(Novozym 435) and $50^{\circ}C$, we attained up to 100% conversion for enzymatic glycosylation of vinyl acrylate and vinyl methacrylate by supersaturated solvent process. The polymerizable glycosyl acrylates and methacrylate are expected to have biomedical application as hydrophilic monomers and hydration modifiers to be used for biocdmpatible hydrogel.

• Fibers and Polymers
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• v.7 no.3
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• pp.229-234
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• 2006

Poly(vinyl acetate) (PVAc)/poly(vinyl alcohol) (PVA)/montmorillonite (MMT) clay nanocomposite microspheres with a core/shell structure have been developed via a suspension polymerization approach. In order to prepare the PVAc/ MMT and PVAc/PVA/MMT nanocomposite microspheres, which are promising precursor of PVA/MMT nanocomposite microspheres, suspension polymerization of vinyl acetate with organophilic MMT and heterogeneous saponification were conducted. A quaternary ammonium salt, cetyltrimethylammonium bromide, was mixed with the MMT in the monomer phase prior to the suspension polymerization. The rate of conversion decreased with an increase in MMT concentration. The incorporation of MMT into the PVAc was verified by FT-IR spectroscopy. Organic vinyl acetate monomers were intercalated into the interlayer regions of organophilic clay hosts and followed by suspension polymerization. Partially saponified PVA/MMT nanocomposite microspheres with a core/shell structure were successfully prepared by heterogeneous saponification.