摘要
The silicon-containing poly (amic acid)s were synthesized from bis (3, 4-dicarboxyphenyl) dimethylsilane dianhydride (SIDA), pyromellitic dianhydride (PMDA) and 4,4′-oxydianiline (4,4'-ODA) in N, N-dimethylacetamide (DMAc). The poly (amic acid) films were obtained by solution-cast method from DMAc solutions and thermally converted into transparent, flexible and tough polyimide films. The wide-angle X-ray diffraction diagrams revealed that all the polyimides possessed amorphous character, and the regulation of those polyimides were decreased with the increase of the molar ratio of SIDA to PMDA. Differential scanning calorimeter measurements showed that the introduction of SIDA to polyimide backbone would make glass transition temperature shift to lower temperature. Thermogravimetric analyses indicated that the silicon-containing polyimides lowered decomposition temperature as compared with PMDA/4, 4′-ODA polyimides. However, UV-visible transmission and reflection spectra showed that the optical transparency of silicon-containing polyimide thin films was superior to that of PMDA/4, 4'-ODA polyimide thin films.
由双 (3,4 苯二甲酸酐 )二甲基硅烷、均苯四甲酸酐和 4 ,4′ 二氨基二苯醚制备了含硅聚酰胺酸 .通过溶液浇铸方法制得聚酰胺酸薄膜 ,经热处理将其转化为聚酰亚胺薄膜 .X 衍射测量表明 ,该类型聚酰亚胺具有非晶态结构 ,且规整性随双 (3,4 苯二甲酸酐 )二甲基硅烷含量的增加而减少 .含硅共聚酰亚胺与传统均苯四甲酸酐 /4,4′ 二氨基二苯醚聚酰亚胺相比 ,呈现较低的玻璃化转变温度和分解温度 ,但共聚酰亚胺中双 (3,4 苯二甲酸酐 )二甲基硅烷含量增加将导致薄膜的透光率增加 .
基金
TheScienceFoundationofSoutheastUniversity(No .92 0 70 4114 0 )
