Preparation and Characterization of Polyurethane/Organoclay Nanocomposites by UV Curing

Abstract

Polyurethane (PU)/organoclay nanocomposites were prepared by mixing UV curable urethane acrylate oligomer with organoclay, and a subsequent curing by UV irradiation. As organoclays, commercially available Cloisite 20A (C20A) and acrylsilane modified C20A were used. XRD and TEM analyses revealed that the UV cured PU/clay nanocomposites formed intercalated nanocomposites, and acrylsilane modified C20A are dispersed more finely than unmodified C20A in PU matrix. DMTA, pencil hardness and adhesion test onto PET substrate showed that the clay nanolayers induced an increase in the properties, and the enhancement in the properties was more pronounced in the PU/acrylsilane modified C20A nanocomposites than in the PU/unmodified C20A nanocomposites. It was also observed that the PU/surface modified clay nanocomposites showed remarkably lower shrinkage upon UV curing than the unfilled PU. The nanocomposites showed excellent optical transparency but lower gloss as compared to unfilled PU.

Evaluation of Fiber Arrangement Condition of CF/PP Composites Using Electrical Resistance Measurement and Wettability

“…주로 우주항공분 야에서는 prepreg를 이용한 가압 공법 또는 오토클래 이브 공법을 사용하지만, 고속 성형을 요구하는 차량 용 부품 시장에서는 열경화성 복합재료 부품을 제조 하는데 한계가 존재한다 [4,5]. 따라서 차량용 부품 또 는 생활용 부품으로 복합재료가 사용되기 위해서는 사출성형을 통한 고속성형이 필요하다 [6,7]. 고속 사출성형을 통해 열가소성 고분자를 기지로 사용한 복합재료가 제조될 수 있다.…”