• Proceedings of the Korean Fiber Society Conference
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• 2003.10a
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• pp.90-90
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• 2003

Living nature was appeared in the cationic polymerization of tort-butyl vinyl ether (TBVE), initiated by iodine, carried out in toluene at -78$^{\circ}C$. It was found that the number average molar mass of the resulting polymer (equation omitted) increases linearly as the conversion to polymer increase which reveals that there is no operation of chain transfer or termination process in this system. The polymers having narrow distribution and having molar mass of the resulting polymers are dependent on molar ratio of monomer and iodine.

• Fibers and Polymers
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• v.3 no.1
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• pp.14-17
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• 2002

Development of a novel fixed site carrier membrane (FCM), supported by PET fabric for metal ion separation is reported. The membranes were prepared by dipping PET fabric into the methylene chloride solution of Poly(5-vinyl-m-phe-nylene-m'-phenylene-32-crown-10) (P(VCE)), a polymeric metal ion carrier. It was found that the flux of mono-valent metal ion transported across the membrane is signif=cantly differed from each other and the flux decreases in the order $Cs^+$>$Rb^+$>$K^+$>$Na^+$>$Li^+$ irrespective to the anion except perchlorate anion. It was explained in terms of the stability of the complex, formed by crown ether unit of the P(VCE) and the various metal ions, meanwhile, the lower rate of transport in the presence of perchlorate anion was ascribed to its low hydrophilicity.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.11a
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• pp.588-591
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• 2002

Radiation technology is an effective way for regulating polymeric materials to physicochemical and mechanical properties. The effect of radiation on mechanical and electrochemical properties of new rubber-like polymeric composite materials based on poly(vinyl ether of ethyleneglycol : PVEEG) have been studied for investigating mechanical and electric property of polymer composites applications.

• Bulletin of the Korean Chemical Society
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• v.16 no.6
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• pp.493-498
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• 1995

Ultrathin networks of itaconic acid copolymers and poly(allylamine) were produced by a Langmuir-Blodgett (LB) technique employing a double-chain amine as a monolayer template which was subsequently removed by extraction after thermal crosslinking. Itaconic acid copolymers used were copoly (itaconic acid-ethyl vinyl ether) and copoly (itaconic acid-n-butyl vinyl ether). The polyion-complexed monolayers of three components consisting of template amine, itaconic acid copolymer and poly (allylamine) were formed at the air-water interface. The Langmuir film properties have been studied by the surface pressure-area isotherm and fluorescence microscopy. The monolayers were transferred on solid substrates and were characterized by FT-IR spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy (SEM). Two-dimensional polymer networks were formed through imide or amide linkages by heat treatment under vacuum. The heat-treated films were extracted with chloroform after immersion in aq. sodium chloride to remove the template amines. SEM observation of a LB film on a porous fluorocarbon membrane filter with pore diameter of 0.1 μm showed covering of the pores by six layers in the polyion complex state.

• Applied Chemistry for Engineering
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• v.9 no.3
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• pp.424-429
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• 1998

Cloud-point data at $230^{\circ}C$ and 1,800 bar are presented for two poly(ethylene-co-vinyl alcohol)(PEVA) copolymers[9.9mol% and 17.8mol% vinyl alcohol(VA)] in ethylene, propane, propylene, n-butane, 1-butene, dimethyl ether(DME), and chlorodifluromethane(CDFM). The static type experimental apparatus with a view cell has been used for the experiment at the high pressure and temperature. The pressure-temperature (P-T) loops of PEVA(9.9mol% VA) copolymer-DME mixtures are presented at copolymer concentrations of 1.4wt% to 20.0wt%. Also, we presented the phase behavior of PEVA(17.8mol% VA) copolymer-DME system at copolymer concentration of 1.9wt% to 6.8wt%. The cloud-point curves for the PEVA copolymers in dimethyl ether showed single phase above 480 bar as a result of the hydrogen bonding between the vinyl alcohol unit and dimethyl ether. The pressure-concentration(P-x) isotherm loops of PEVA(9.9mol% and 17.8mol% VA)-DME system are obtained. The cloud-point curves for PEVA(9.9mol% and 17.8 mol% VA) copolymers andthe ethylene, propane, propylene, n-butane, 1-butene, and CDFM all show negative slopes of phase behavior and are located at pressures below 1,800 bar. For PEVA copolymer-DME system(9.9mol% VA), cloud-point curves show positive slopes that decrease in pressures with decrease in temperature in the temperature range of $80^{\circ}C$ to $160^{\circ}C$.

• Proceedings of the Korean Fiber Society Conference
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• 2001.04a
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• pp.31-34
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• 2001

• Bulletin of the Korean Chemical Society
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• v.15 no.10
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• pp.913-916
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• 1994

• 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.

• Bulletin of the Korean Chemical Society
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• v.20 no.5
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• pp.567-572
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• 1999

5-Nitro-2-(2'-vinyloxyethoxy)benzylidenemalononitrile (2a), methyl 5-nitro-2-(2'-vinyloxyethoxy)benzylidenecyanoacetate (2b), 3-nitro-4-(2'-vinyloxyethoxy)benzylidenemalononitrile (4a), methyl 3-nitro-4-(2'-vinyloxyethoxy)benzylidenecyanoacetate (4b), 2-nitro-5-(2'-vinyloxyethoxy)benzylidenemalononitrile (6a), and methyl 2-nitro-5-(2'-vinyloxyetboxy)benzylidenecyanoacetate (6b) were prepared by the condensation of 5-nitro-2-(2'-vinyloxyethoxy)benzaldehyde (1), 3-nitro-4-(2'-vinyloxyethoxy)benzaldehyde (3), and 2-nitro-5-(2'-vinyloxyethoxy)benzaldehyde (5) with malononitrile or methyl cyanoacetate, respectively. Vinyl ether monomers 2a-b, 4a-b, and 6a-b were polymerized with boron trifluoride etherate as a cationic initiator to yield poly(vinyl ethers) 7-9 having oxynitrobenzylidenemalononitrile and oxynitrobenzylidenecyanoacetate, which is effective chromophore for second-order nonlinear optical applications. Polymers 7-9 were soluble in common organic solvents such as acetone and DMSO. Tg values of the resulting polymers were in the range of 67-83 ℃. Electrooptic coefficient (r33) of the poled polymer films were in the range of 15-27 pm/V at 633 nm. Polymers 7-9 showed a thermal stability up to 300 ℃ in TGA thermograms, which is acceptable for NLO device applications.

• Korean Membrane Journal
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• v.9 no.1
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• pp.52-56
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• 2007

A proton exchange membrane was prepared by ${\gamma}-irradiation-induced$ grafting of styrene into poly(tetrafluoro-ethylene-co-perfluoropropyl vinyl ether) (PFA) and subsequent sulfonation reaction. The degree of grafting (DOG) increased with an increase in the absorbed dose. The prepared membranes showed high ion exchange capacity reaching 3.0 meq/g, which exceeded the performance of commercially available perfluorosulfonic acid membranes such as Nafion. The proton conductivity of PFA-g-PSSA membrane increased with the DOG and reached 0.17 S/cm for the highest sample at room temperature. The DMFC performance of the prepared membranes with 50% DOG was comparable to that of Nafion membrane.