笼型倍半硅氧烷/聚酰亚胺复合薄膜的合成及性能

Studies on Preparation and Properties of POSS/PI Hybrid Films

以溶胶凝胶法制备得到一类新型笼型倍半硅氧烷(G-POSS)/聚酰亚胺(PI)复合薄膜。通过红外反射光谱(DRIFT-IR)、扫描电子显微镜(SEM)表征了其结构与薄膜断面形貌,以热重分析(TGA)和机械性能分析研究了薄膜的耐热性、室温(25℃)和低温(77 K)下的力学性能。结果表明,在掺杂质量分数低于5%时,该复合薄膜耐热性保持稳定,同时在室温和低温下都表现出优于纯PI膜的拉伸强度,其中在G-POSS掺杂质量分数为3%时,复合薄膜的拉伸强度为235 MPa(77 K),比纯PI膜提升了9%。掺杂质量分数低于5%的该型复合薄膜具有较好的热性能和机械性能。

A series of polyhedral oligomericsilsesquioxane（ POSS） / polyimide（ PI） hybrid films were prepared by the sol- gel technique. Particular structural,morphological,mechanical and thermal properties of the G-POSS / PI nanocomposite films were investigated by DRIFT- IR,SEM,TGA,and universal tester,i. e.,the tensile strength of the hybrid films were higher than pure PI both at cryogenic and room temperature. The highest tensile strength of the G- POSS / PI films was 235 MPa by incorporating 3% G- POSS at 77 K and 9%stronger than pure PI. That’s mainly attributed to the tighter arrangement and more intense interaction between the two components. As a consequence,the hybrid film with lower than 5% POSS content（ e. g.,3%） would be more possibly used as a kind of novel material at cryogenic temperature compared with pure PI film in the cryogenic refrigeration technology and inertial confinement fusion（ ICF） physics experiments.