• Bulletin of the Korean Chemical Society
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• v.19 no.11
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• pp.1262-1265
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• 1998

• Macromolecular Research
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• v.17 no.8
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• pp.563-567
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• 2009

In order to improve the thermomechanical performance of polyketone, a third monomer (4-methylstyrene) was added to the copolymerization system. The terpolymer of CO, styrene, and 4-methylstyrene was synthesized in the presence of multi component catalysts containing palladium acetate and rare earth metal phosphonates. The products were characterized by infrared spectroscopy (IR), and nuclear magnetic resonance spectroscopy (NMR). The effects of the different components, including the third monomer, palladium acetate, 2,2'-bipyridyl, rare earth phosphonate, p-toluene-sulphonic acid, and p-benzoquinone, were also studied. The highest catalytic activity of 965.51 g/(gPd h) was obtained with a catalyst containing palladium acetate and rare earth phosphonate.

• Polymer(Korea)
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• v.26 no.3
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• pp.293-299
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• 2002

By the reaction of m-cresol as a microbicide with acryloyl chloride m-cresyl acrylate (CA) was synthesized, and polymers with the moiety of m-cresol were prepared by the radical terpolymerization of CA -methylmethacrylate -acrylic acid. The contents of CA unit in the polymers were found to be 4.7 mol% and 10.1 mol% from their nuclear magnetic resonance spectra. The number -average molecular weights of the polymers were in the range of 12000 to 15000. Through the hydrolysis of the polymers m-cresol was released. The release rate of the microbicide increased with increasing PH of the release medium. This result can be attributed to enhanced proton dissociation of carboxyl group of the acrylic acid unit in the polymers. These polymers showed microbicidal activities for S. aureus as a positive microbe and E. coli as a negative microbe.

• Polymer(Korea)
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• v.27 no.5
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• pp.443-448
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• 2003

2-Biphenylyl acrylate (BPA) was synthesized by the reaction of 2-phenylphenol as a microbicide with acryloyl chloride, and copolymers with the moiety of 2-phenylphenol were prepared by the radical terpolymerization of BPA-methylmethacrylate-acrylic acid. The contents of BPA unit in the poly mers were found to be 4.2 mol% and 9.1 mol% from their nuclear magnetic resonance spectra. The number average molecular weights of the polymers were in the range of 15000 to 16000. 2-Phenylphenol was released through the hydrolysis of the polymers. The release rate of the microbicide increased with increasing pH of the release medium. The released solution showed higher microbicidal activity for E. coli as a negative microbe than S. aureus as a positive microbe.

• Elastomers and Composites
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• v.48 no.4
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• pp.269-275
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• 2013

In this study, we prepared poly(ethylene-ter-1-hexene-ter-divinylbenzene) using various metallocene catalysts with trityl tetrakis(pentafluorophenyl)borate/triisobutylaluminium cocatalysts system. We tried rac-$Et(Ind)_2ZrCl_2$, rac-$SiMe_2(Ind)_2ZrCl_2$, and rac-$SiMe_2(2-Me-Ind)_2ZrCl_2$ to choose optimum metallocene catalyst, comparing with catalytic activity, molecular weight, molecular weight distribution of the terpolymers. To study the effects of chain length of high ${\alpha}$-olefins on the terpolymerization, we synthesized the terpolymers using 1-hexene, 1-octene, 1-decene or 1-dodecene. We characterized chemical composition, thermal properties, and mechanical properties of the terpolymers.

• Elastomers and Composites
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• v.48 no.4
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• pp.263-268
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• 2013

In this study, we prepared poly(ethylene-ter-1-hexene-ter-divinylbenzene) using bridged rac-$Et[Ind]_2ZrCl_2$ metallocene catalysts. The effect of 1-hexene on the terpolymerization rate was evaluated. When cocatalyst/catalyst molar ratio was 3,000, catalytic activity indicated more than 8,000 which was very remarkable value. As polymerization time increased, the weight-average molecular weight of the terpolymer gradually increased to some degree. In case of a polymerization time of 50 minutes, the terpolymer became amorphous state. The molecular weight distribution and densities of the terpolymer were 110,000-200,000 and $0.85-0.89g/cm^3$, respectively. Thermal properties and structure of the terpolymer were also identified.

• Elastomers and Composites
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• v.55 no.4
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• pp.249-256
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• 2020

Superabsorbent polymers (SAPs) can absorb and retain ten to thousand times their dry mass of water because of their three-dimensional hydrophilic structures. Conventional SAPs are mainly composed of poly(acrylic acid sodium salt) derived from petrochemicals. The present work is aimed at limiting the use of the petrochemical component by replacing it with a biomass-based material. First, the core-SAP was prepared via the terpolymerization of itaconic acid, vinylsulfonic acid, and cellulose, and the optimum conditions in terms of material input ratio were determined. Following this, the core-SAP was surface-crosslinked by esterification with butane diol to improve its liquid permeability and absorbency under load (AUL). The liquid permeability was measured according to the amount of 0.9 wt.% NaCl solution passing between the swollen SAP particles under a given pressure, and the AUL was estimated from the weight of this solution absorbed under 0.3 psi pressure.

• Proceedings of the Membrane Society of Korea Conference
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• 1997.10a
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• pp.83-84
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• 1997

1. INTRODUCTION : Polyimides containing siloxane moiety(poly(imide siloxane), or polysiloxaneimide) have been synthesized because of their some merits over polyimide itseft. Polyimides have excellent thermal and mechanical properties but their poor solubility and processibility in their fullly imidized form give disadvantages in applications. Incorporation of siloxane units make it possible to increase solubility and processibility, and also impart impact resistance, low moisture uptake, low dielectric constant, thermo-oxidative resistance, good adhesion properties to substrate and etc.. Incorporation methods of siloxane groups into the polyimide was mainly copolymerization or terpolymerization between oligomeric dimethylsiloxane and aromatic dianhydride. A few methods of introducing siloxane units in functional groups of polyimide was reported. In our laboratory poly(amideimide siloxane) and poly(imide siloxane) were prepared and the study about their thermal kinetics was performed. In separation membrane area, polysiloxaneimides was utilized in pervaporation and gas separation. Polyimides in gas separation show high selectivity and very low permeability, and introduction of siloxane segments increase permeability with low decrease in selectivity. We aimed to introduce silicone segments into poly(amic acid) state and synthesize polymer partially imidized, and also show the gas separation characteristics of the synthesized polymer.

• Elastomers and Composites
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• v.48 no.1
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• pp.85-91
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• 2013

In this study, we synthesized a terpolymer consisting of ethylene, 1-hexene, and styrenic monomer using a metallocene catalyst and cocatalyst ststem. The styrenic monomers empolyed as the third monomer were styrene, p-methylstyrene, and 4-tert-butylstyrene. The structure and composition of the terpolymers were characterized using $^{13}C$ NMR and $^1H$ NMR. Catalytic activity, polymer yield, molecular weight and molecular weight distribution of the terpolymers were analyzed. We also determined the glass transition temperature(Tg), crystallinity and thermal properties of the terpolymers by DMA, WAXS and TGA.

• Polymer(Korea)
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• v.30 no.4
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• pp.326-331
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• 2006

MMA(methyl methacrylate)/IPMI(N-isopropyl maleimide) copolymers are one of the well known heat resistant materials for POF(plastic optical fiber). However, because of the large difference in the reactivity ratio between MMA and IPMI$(r_1/r_2=1.72:0.17)$, the compositional drift occurs during the polymerization process which causes the deterioration of the physical properties of these copolymers. In this paper, we report that the compositional drift of the copolymer could be reduced by the addition of styrene (St) which increased the reactivity of IPMI in the MMA/IPMI copolymerization system and conversion was also increased by 1.5 or 2 times. The MMA/IPMI/St terpolymer had higher refractive index than the MMA/IPMI copolymer which depended on the contents of sytrene.