联苯四甲酸二酐异构体对聚酰亚胺性能的影响

Effect of isomeric biphenyltetracarboxylic dianhydride on the properties of polyimide

采用4-PEPA(4-苯乙炔基苯酐)为封端剂,4,4′-ODA(4,4′-二氨基二苯醚)为胺源,通过控制s-BPDA(3,3′,4,4′-联苯四甲酸二酐)和α-BPDA(2,3,3′,4′-联苯四甲酸二酐)两种二酐单体的比例,合成了五种苯乙炔基封端的聚酰亚胺低聚物,对其化学结构、热性能及粘接性能进行了研究。研究结果表明:低聚物均具有较高的玻璃化转变温度(Tg),α-BPDA的引入减弱了分子链结晶倾向;当s-BPDA等时,常温剪切强度为15.3 MPa;而当两者用量比为67∶33时,高温剪切强度相对较高,同时保持了较好的耐热性能。

Using 4-PEPA(4-phenylethynyl phthalic anhydride)as end-capping agent,4,4′-ODA(4,4′-oxydianiline) as amine source,by controlling the ratio of s-BPDA(3,3′,4,4′-biphenyltetracarboxylic dianhydride)and α-BPDA(2,3,3′,4′-biphenyltetracarboxylic dianhydride)monomers,five kinds of polyimide oligomers with phenylethynyl end-capping were synthesized. The chemical structure,thermal properties and bonding properties were investigated. The research results showed that the oligomers had higher glass transition temperatures(Tg),and the introduction of α-BPDA weakened the tendency of molecular chain crystallization.When the contents of s-BPDA and α-BPDA were equal,the shear strength at room temperature was 15.3 MPa. And when the dosage ratio of them was 67∶33,the shear strength at high temperature was relatively high,while maintaining good heat resistance.