Morphology and mechanical properties of cured epoxy systems chemically modified with aminopropyl-terminated dimethyl siloxane homooligomer and dimethyl-diphenyl siloxane cooligomer, oxiranylmethoxypropyl-terminated dimethyl siloxane homooligomer and dimethyl-diphenyl siloxane cooligomer were investigated. Especially, blending method of siloxane oligomer was performed by two kinds of method, which are chemical blending method and mechanical blending method. Cured epoxy system in chemical blending method could reduce the thermal expansion coefficient and flexural modulus more effectively than those in mechanical blending method. Also, cured epoxy system of aminopropyl-terminated siloxane oligomer could increased the mechanical properties more effectively than those of oxiranylmethoxypropyl-terminated siloxane oligomer. Increasing the percentage of diphenyl units of siloxane oligomer raised T_g of siloxane oligomer and decreased the domain size.

Aminopropyl-terminated dimethyl siloxane homooligomer 및 dimethyl-diphenyl siloxane cooligomer와, oxiranylmethoxypropyl-terminated dimethyl siloxane homooligomer 및 dimethyl-diphenyl cooligomer로 반응시킨 경화 에폭시 수지의 morphology 및 기계적 성질에 관하여 검토하였다. 특히 siloxane oligomer의 첨가방법을 chemical blending 법과 mechanical blending의 두가지 방법으로 행하였다. 이 결과 chemical blending법에 의한 경화 에폭시계가 mechanical blending법 보다 열팽창계수 및 flexural modulus를 더 감소시킬 수 있었고, 마찬가지로 aminopropyl-terminated siloxane oligomer의 사용이 oxiranylmethoxypropyl-terminated siloxane oligomer의 사용보다 열팽창계수 및 flexural modulus를 더 감소시킬 수 있었다. 그리고 siloxane oligomer의 diphenyl의 농도가 증가함에 따라 siloxane oligomer의 T_g는 증가하였고 domain의 크기는 감소함을 알 수 있었다.