聚酰亚胺/纳米二氧化硅复合薄膜的研究

Study on polyimide/nano-silica hybrid films

采用溶胶-凝胶法制备了聚酰亚胺／纳米二氧化硅(SiO2)复合薄膜,研究了SiO2含量对复合膜性能的影响。结果表明,复合膜的密度随SiO2含量的增加而增大,与其SiO2含量基本上呈线性关系;与纯聚酰亚胺薄膜相比,复合膜中SiO2含量达到30～40%时,导热系数可提高1倍以上;表观分解温度随SiO2含量的增加先增大后减小,SiO2含量大约在10～20%时达到最大值;SiO2含量不大于10%时,拉伸强度变化不大或略有增加,随着SiO2含量的继续增加,拉伸强度则迅速下降;复合膜常态下的体积电阻率当SiO2含量不大于10%时变化不大,但体积电阻率受湿度影响较大。

The polyimide/nano-silica hybrid films were prepared by sol-gel process.The influˉence of silica content on the properties of the films was investigated.The results show that the relationship between density of the films and the silica content is basically linear.Compared with the pure polyimide films,the thermal conductivity is improved when SiO 2 is intruduced into the films,which achieves the maximum when the silica content is within30～40%.With the silica content increasing,the apparent decomposition temperature reaches the maximum when the silica content within10～20%.The tensile strength of the films changes lightly or increases a little when the silica content is less than10%,however,if the silica content is greater than10%,the tensile strength decreases rapidly.The electric volume resistivity of hybrid films at normal conditions changes slightly when the silica content is less than10%.However,humidity affects the electric volume resistivity remarkably.