苯乙炔封端的BTDA系列酰亚胺预聚体的研究

Phenylethynyl End-capped Polyimide Oligomers Derived from BTDA

合成了具有苯侧基的二胺单体1,4-双(4′-氨基苯氧基)-2-(苯基)苯(p-TPEQ),并与3,3′,4,4′-苯酮四羧酸二酐(BTDA)进行缩聚反应,分别以4-苯乙炔苯酐(PEPA)和4-苯乙炔-1,8-萘二甲酸酐(PENA)作为封端剂,合成了两个系列的苯乙炔封端的酰亚胺预聚体.DSC测试结果表明,此类预聚体具有比PETI-5更宽的加工窗口;利用所合成的预聚体制成了具有较高热分解温度热固性交联PI薄膜.结果表明,PI预聚体加工性能良好,其交联后具有优异的力学和热学性能;同时PEPA封端的预聚体树脂具有比PENA封端的树脂更为优异的综合性能.

A diamine monomer [ 2,5-bis （4-aminophenoxy） biphenyl （p-TPEQ） ] was synthesized by four-step routes, and 4-（ 1-phenyl ethynyl）-1, 8-naphthalic anhydride （PENA） was synthesized and characterized as well. Two series of phenylethynyl-terminated imide oligomers were prepared by reacting BTDA with p-TPEQ, and end-capped with 4-phenylethynylphthalic anhydride （PEPA） or PENA. The thermal curing processes of the oligomers were investigated by FTIR, differential scanning calorimetry. As a result of undergoing a complex reaction of the phenylethynyl in the heating run, Tg increased with the increase of content of phenylethynyl. The obtained imide oligomers were molded into films. The cured films exhibited excellent mechanical properties and thermo-oxidative stability. All the results indicate that the incorporation of p-TPEQ monomer can increase the solubility and processing ability of the oligomers.