As a part of the project to study the effect of fiber surface modification on the physical properties of HDPE/carbon fiber composites, the influences of such factors as the type of coupling agents(toluene-soluble and toluene-insoluble HDPE-g-PAAm's), the oxidation treatment of fiber surface(by KMnO₄-H₂SO₄), the concentration of surface-treatment solution or suspension, the treatment time, and the temperature upon the amount of graft polymers(GP) adsorbed onto the fiber surface, adsorption behavior, and the states of the adsorbed layer have been investigated in the present study. The PAAm portion of the graft polymer was found to be adsorbed on the fiber surface whereas the PE portion was located at the water- or toluene-phase. The adsorption has been confirmed to occur reversibly, and the GP's heterogeneous in molecular weight and composition took longer time to reach the equilibrium or redistribution state in adsorption. In addition, in case of the water-dispersible GP the amount adsorbed on the fiber surface decreased with the increasing PAAm content of the GP, but in case of the toluene-soluble GP the adsorbed amount decreased with the increasing temperature of the treatment solution. It was also revealed that the adsorbed amount of the water-dispersible GP towards the oxidized carbon fiber generally increased as compared with the unoxidized fiber.

탄소섬유(CF) 표면개질용으로 합성된 두 종류의 GP(HDPE-g-PAAm)를 미산화 및 KMnO₄-H₂SO₄계 산화제로 산화시킨 CF에 대하여 수분산성 GP의 경우는 GP를 물에 분산시키고, 비수분산성 GP의 경우는 toluene에 용해시켜서 각 분산액 및 용액의 농도, 온도 및 처리시간에 따른 흡착량, 흡착거동 및 흡착층의 상태를 검토하는 한편 GP를 구성하는 HDPE 및 PAAm의 조성에 따른 GP의 흡착에 대하여도 검토하였다. g-PAAm성분은 CF표면에 흡착하고 graft된 PE(g-PE)성분은 수상 또는 toluene층에 존재한다. 흡착은 탈착을 수반하여 가역적으로 일어나며 분자량 및 조성에서 다분산상인 GP의 흡착평형에 많은 시간이 필요하며 흡착재분배가 일어났다. 수분산성 GP는 g-PAAm의 함량이 많을수록 또한 비수분산성 GP는 처리하는 toluene용액의 온도가 높을수록 흡착량이 감소하였으며, 산화된 CF에서 수분산성 GP의 흡착량은 대체로 증가하였다.

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