To improve the interfacial adhesive strength between cellular matrix and filler in rigid polyurethane foam, the surface of filler was treated with coupling agent. Silane and titanate derivatives were used as coupling agents. The influence of addition of surfactant to coupling agent on the adhesive strength was also examined. The effect of surface treatment on the compressive properties of polyurethane foams were discussed by examining the combining equation of Padawer & Beecher''s and Rusch''s equations; the former equation could be applied to the matrix filled with discontinuous platelet filler, the latter generally to the foams. In case of reinforced foam, by treating the surface of platelet filler with coupling agents, both compressive modulus and compressive strength were found to be improved. Compressive property of foam the filled with titanate treated mica was better than that of foam filled with silane treated mica. It was found that the surfactant has an excellent effect on the compressive properties. The cell structure was obviously destroyed when more than 20wt. % of mica was loaded.

경질 Polyurethane foam의 cellular matrix와 보강재인 mica-flake의 계면 접착력을 향상시키기 위하여 mica-flake를 coupling agent로 표면처리하여 혼합사용하였다. Coupling agent처리를 silane계와 titanate계로 사용하였으며 이때 계면활성제의 효과도 병행하여 실험하였다. 보강 foam에 대한 이론강도식으로는 불연속 판상충전제 충전율에 대한 Padawer & Beecher의 이론식과 비보강 foam에 잘 적용이 되는 Rusch의 실험식으로부터 복합식을 유도하여 실험결과와 비교하였다. 판상충전제를 표면처리하여 충전시킨 경우에 압축탄성율과 압축강도는 모두 향상된 결과를 나타냈으며, 압축특성은 titanate 계가 silane 계보다 좋았고 계면활성제의 효과도 크게 기여함을 알 수 있었다. 구조적으로 mica 함량이 20wt% 이상 충전된 경우 cell의 급격한 파괴를 일으켰다.

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