In order to know the effect of the composition and structure of the coupling agent(the graft copolymer on mechanical properties of carbon fiber(CF) reinforced isotactic polypropylene(IPP) laminated composites, IPP-g-PAAm(Polyacrylamide) copolymer were synthesized by the "inverse emulsion graft polymerization technique" at various amounts of emulsifier(0.03, 0.05, and 0.08ml of Tween 80). AAm conversion, PP conversion, % grafting, grafting efficiency were investigated, and the production ratio of the respective types(i.e., water-dispersible(WD), methanol-dispersible(MD), and toluene-soluble(TS) graft polymer) were dependent on the PAAm content in the resulting graft copolymers(GP). In addition, to make the laminated composites by the film method, the IPP prepregs were prepared with the CF treated with GP differing in type and amount of emulsifier under IPP sheet at optimum molding conditions. These optimal condition was based on the consideration of uniformity of dispersed fiber in IPP matrix and the observation of fiber-matrix interfacial microstructure within the impregnated(prepreg) strand via optical microscopy. From this study, it was found that among the random oriented short CF/IPP composites(ν_f=ca. 20.5%) treated with 3 different graft polymers(GP), the case of TSGP showed the highest impact energy measured by the steel-ball typed impact test, while in the case of the 4-ply cross-typed laminated CF/IPP composites(ν_f=ca. 28%) with the GP's of only WD type, the case of smaller amount of emulsifier exhibited better tensile properties and impact behavior.

탄소섬유강화 isotactic polypropylene(IPP) 복합재료의 기계적 특성에 미치는 graft polymer,인 ,coupling agents의 구조와 조성의 효과를 검토하기 위하여 여러 농도의 유화제 상태하에서 IPP-g-PAAm copolymer를 역유화법으로 합성하여 AAm conversion, PP conbersion, % grafting과 (MD), 그리고 톨루엔가용(TS) graft polymer)는 중합된 graft copolymer내의 PAAm의 함량에 의존하다. 또한 복합재료를 만들기 위한 IPP prepreg는 film법에 의해 최적 molding 상태에서 IPP-g-PAAm의 종류와 유화제량을 달리하여 합성된 GP로 처리된 탄소섬유로 제작되었다. 이 최적상태는 광학현미경을 통한 IPP, 수지에 분산된 섬유의 균일도에 의하고 섬유와 수지간의 미세고조를 관찰하여 결정하였다. 본 연구에서 3가지의 다른 GP로 처리된 random 배향된 단섬유 복합재료(v_f=20%)중 강구충격시험에서 TSGP가 가장 큰 impact energy를 보였고, 그 반면에 4-ply 직교로 적층된 CF/IPP 복합재료(v_f=28%)의 경우에는 작은 유화제를 사용한 쪽이 더 나은 인장과 충격치를 나타내었다.

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