The adsorption behavior of two types of graft polymers(GP) , water-dispersible and toluene-soluble isotactic polypropylene-polyacrylamide graft polymer(IPP-g-PAAm), synthesized for the surface-modification of carbon fiber used for reinforcing isotactic polypropylene matrix has been examined through analysis of the effects of the treating time and temperature, and the pH value of the reaction system on the amount of the GP adsorbed on carbon fiber. In addition, fiber pull-out tests were made on carbon fibers treated with GP's prepared under varying treating times and emulsifier concentrations to investigate the effect of the adsorption amount of GP on the interfacial bond strength between fiber and matrix, whose results have been confirmed by the observation of the interfacial microstructure(transcrystallinity) using polarizing microscope. From the present study it has been found that the amount of GP adsorbed on fiber was largely affected by the concentration of GP, treating time and temperature, and the amount of emulsifier upon graft polymerization, and that the increase in adsorption amount of GP resulted in the increase in density of the transcrystalline layer developed at the interface between fiber and matrix, and hence the increase in interfacial shear strength within the range of interest.

탄소섬유(CF)표면개질용으로 합성된 수분산성 및 비수분산성 isotactic polypropylene-polyacrylamide graft polymer(IPP-g-PAAm)가 CF에 흡착하는 거동을 규명하기 위하여 처리시간. 처리온도, 처리용액의 농도 및 pH, graft polymer(GP)합성시의 유화제의 량등에 따른 CF에의 흡착량을 검토하였다. 그리고 이들 GP의 흡착량이 계면접착강도에 미치는 영향을 검토하기 위하여 pull-out 시험용 시험편을 만들어 처리시간과 유화제의 량에 따른 계면전단강도의 변화를 측정하였으며, 편광현미경을 이용하여 계면조직의 transcrystallinity를 관찰하였다. GP의 흡착량은 GP의 농도, 처리시간, 처리온도 및 GP중합시의 유화제의 량에 크게 의존하였고. 일정 범위내에서 GP의 흡착량이 많을수록 CF와 IPP수지간의 계면전단강도는 증가하였으며, 계면조직상에 나타난 transcrystallinity의 밀도가 클수록 계면전단강도는 증가하였다.

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