【摘要】 将二胺单体1,3-双(4-氨基苯氧基)苯(1,3,4-APB)、3,4-二氨基二苯醚(3,4-ODA)分别与3,3′,4,4′-联苯四酸二酐(s-BPDA)和1,4,5,8-萘四甲酸二酐(NTDA)进行缩聚反应,并在两种不同合成条件下合成三种苯乙炔苯酐(PEPA)封端的聚酰亚胺低聚物(PI1、PI2、PI3)。结果表明,含六元酸酐环的NTDA与二胺反应不仅形成酰亚胺结构,而且还形成异酰亚胺结构,并且酸性条件下更有利于酰亚胺结构的形成。这三种以苯乙炔苯酐封端的低聚物均具有良好的加工性能和热性能,有很宽的加工窗口,5%热失重温度均在530.0℃以上。萘环的引入使低聚物固化前后的玻璃化转变温度均有所提高,但也使得低聚物黏度上升。更多还原

【Abstract】 The synthesis and characterization of phenylethynyl end-capped polyimide oligomers,designated PI1,PI2 and PI3,derived from 3,3’,4,4’-biphenylene dianhydride(s-BPDA),1,4,5,8-naphthalenetetracarboxylic dianhydride(NTDA),1,3-bis(4-aminophenoxy)benzene(APB),3,4-diaminodiphenyl ether(3,4-ODA) and 4-phenylethynylphthalic anhydride(4-PEPA) under different reaction conditions are described.It was found that both naphthalimide and naphthalisoimide structures were formed during condensation of the six-membered naphthalene anhydrides with aromatic diamines;the naphthalimide structure was more readily formed under acid conditions.All the polyimide oligomers exhibited good processabilities and excellent thermal properties with large processing windows and high 5% weight loss temperatures(>530.0 ℃).Although NTDA afforded oligomers with higher Tg than s-BPDA,their processability was slightly inferior.更多还原