分子结构对聚酰亚胺的合成及性能的影响

Influences of molecular structures on synthesis and properties of polyimide

以PMDA(均苯四甲酸酐)和ODPA(单醚酐)为主要原料,制备了两种分子结构的聚酰亚胺(PI)膜,并考察了其预聚体聚酰胺酸(PAA)溶液的特性黏度[η]和亚胺化后PI膜的力学性能、热性能。研究结果表明:PAA溶液的[η]随分子链柔性增加而递减;亚胺化后醚键相对较多的PI能够改善大分子链的柔韧性,使其具有较好的膜基附着力、柔韧性和抗冲击强度;两种结构PI膜的热分解温度均超过510℃。

With PMDA （pyromellitic anhydride） and ODPA （monoether anhydride） as main raw materials, two polyimide （P1） films with different structures were prepared, and their inherent viscosity[η] of prepolymer polyamide acid （PAA） solution, and mechanical property and thermal property of PI films after imine were investigated. The research results showed that the [η] of PAA solution was progressively decreased with increasing molecular chain flexibility. Because the PI with relatively more ether bond after imine could improve the flexibility of macromolecular chain, so it has the good film adhesion, flexibility and impact strength. The thermal decomposition temperatures of two PI films with different structures exceed all 510℃.