• Proceedings of the Membrane Society of Korea Conference
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• 1996.10a
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• pp.71-72
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• 1996

Polyetherimide(PEI)계의 고분자는 막 성능이 우수하고 내열성과 내유기용매성 등이 우수한 열가소성수지로서 film, sheet, tubular형으로 만들 수 있어 한외여과막이나 역삼투막, 기체분리막 등에 이용되고 있다. 한편 투과속도를 높이고, fouling을 줄이기 위한 친수성 향상은 막 소재의 화학적 개질에 있어서 주된 목표이다. sulfonation은 막 재질의 소수성을 감소시켜 water permeability를 향상시키는데 있어서 매우 유용한 방법으로 이온교환수지, 이온교환막, anion형 하전막의 제조에 이용되어 왔다. 본 실험에서는 polyetherimide계 고분자를 chlorosulfonic acid(CSA)를 이용하여 술폰화시킨 sulfonated polyetherimide(SPEI)를 제조하여 막 성능을 측정하였다.

• Proceedings of the Korean Nuclear Society Conference
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• 1995.05b
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• pp.957-963
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• 1995

촉매탑에서 수소와 물 사이의 수소동위원소 교환반응에 사용되는 소수성 고분자 촉매 집합체제조 기술개발을 위하여, 촉매담체를 소수성 수지를 이용하여 충전물 표면에 효과적으로 Binding 시키기 위한 Surface coating 특성에 대하여 연구하였다. 실험에서 먼저 Teflon 수지에 잘 혼합된 Activated carbon을 Ceramic berl - saddle 등의 3가지 형태의 충전물 표면에 Coating시켜 소결 온도, 충전물의 형태 및 표면 위치에 따른 Coating 특성에 대하여 연구하였다.

• Elastomers and Composites
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• v.48 no.2
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• pp.133-140
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• 2013

Carbon fiber reinforced polymer (CFRP) composites consist of carbon fibers in a polymer matrix. Recently, CFRP composites having high thermal stability and low outgassing are finding their use in high performance materials for aerospace and electronics applications under high temperature and high vacuum conditions. Cyanate ester resin is one of the most suitable matrix resins for this purpose. In this study, proper combination of cyanate ester and catalyst, curing behavior, and cure cycle were determined by chemorheology. Optimum condition was found to be catalyst content of 100 ppm and curing temperature of $150^{\circ}C$. Thermal stability and outgassing of cured resin composition were analyzed and the results showed thermal decomposition temperature of $385^{\circ}C$ and total mass loss of 0.29%. The CFRP prepregs and subsequent composites were fabricated by predetermined resin composition and the cure condition. Tensile moduli of the composites were compared with theoretical models and the results were very consistent.

• Polymer(Korea)
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• v.24 no.4
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• pp.556-563
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• 2000

In general, the development of thermoplastic composites has been confronted with difficult problems such as the weak bonding strength between fibers and matrix. However, now, such problems are being surmounted by the development of resins, the improvement of processes, and introduction of interphase. Especially, the introduction of interphase between fiber and matrix can help a dissipation of the impact energy and provide a good adhesion between fibers and matrix. In this study, polymeric interphase was introduced by electrodeposition, modified polypropylene was added to improve the weak bonding strength between interphase and polypropylene matrix. By evaluation of interlaminar shear strength and impact strength of the composites, it was found that composites with introduced composites showed higher mechanical properties than those of composites without interphase. Reactive polymers which have either anhydride or free acid functional group were used as interphase materials, and these polymers also behave as charge carrier in aqueous solution during the electrodeposition process. Weight gain on the carbon fibers was evaluated by changing process parameters such as concentration of solution, current density, and electrodeposition time.

• Composites Research
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• v.12 no.6
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• pp.15-21
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• 1999

Carbon fibers were coated with carboxy modified poly(hydroxy ether)(C-PHE, water dispersed), water soluble polymers poly(hydroxy ether ethanol amine)(PHEA) or water insoluble poly(hydroxy ether)(PHE). Interfacial shear strength of polymer coated carbon fibers was measured by micro-droplet tests with vinyl ester resin, and approximately 30 samples were tested. The interfacial adhesion of poly-mers to carbon fibers was also evaluated, and diffusion behavior of polymer films in vinyl ester resin was investigated. The carbon fibers after testing and diffusion samples were analysed by SEM in order to understand adhesion mechanism. Interfacial shear strength of carbon fibers was enhanced by the coating of PHE and C-PHE which have good or marginal solubility in vinyl ester resin, respectively, but not by the coating of PHEA possibly due to the poor solubility in vinyl ester resin.

• Polymer Science and Technology
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• v.4 no.6
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• pp.423-431
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• 1993

• Polymer Science and Technology
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• v.4 no.1
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• pp.35-44
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• 1993

• Polymer Science and Technology
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• v.4 no.2
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• pp.89-97
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• 1993

• Polymer Science and Technology
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• v.7 no.4
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• pp.371-376
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• 1996

• Polymer Science and Technology
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• v.3 no.5
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• pp.406-411
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• 1992