纳米SiO2改性聚酰亚胺的研究进展

聚酰亚胺(PI)作为一种功能材料,具有良好的介电性、优良力学性能,已被广泛应用于航空航天及微电子领域,但其明显的吸水性和热膨胀性限制了其在高温和精密状态下的应用。纳米SiO2具有很低的热膨胀系数和较低的吸水性,非常适合于对PI的改性。介绍了纳米SiO2的生产原理、纳米SiO2／PI复合材料的制备方法、性能及其在气体分离膜、光电材料、摩擦材料及包装材料方面的应用,并对这类材料的研究方向提出了自己的建议。

Advances in Polyimide Hybrid Materials with Nanometer SiO2

Polyimides (PI) have been considered to be suitable matrix polymers for advanced technological applications in the microelectronics and aircraft industries,because they possess excellent chemical,physical,thermal and mechanical properties. As market demand for higher-performance electronic devices with smaller size,lighter weight,and better quality increases,the high coefficient of thermal expansibn and moisture absorption of Pis has limited their application in higher-performance electronic devices at high temperature. At present ,one of the best ways to improve properties of PI is to add nanometer silica dioxide to PI matrix,yielding PI/SiO2 hybrid nanocomposites,because SiO2 has a much higher thermal stability,lower moisture absorption and higher hardness. In this paper,the preparation methods of nanometer SiO2 are described first, folio wed by the preparation methods of PI/SiO2 hybrid materials,such as the "sol-gel" process and "Insitu polymerization". In addition, their properties and application in gas separation membrane and friction,microelectronic and photonic materials are summarized. Future prospect of PI/SiO2 hybrid nanocomposites is predicted.