聚芳醚酮单体结构与反应活性的研究

Research on Monomer Structures and Reactivity of Poly(aryl ether ketone)s

利用从头算ＲＨＦ方法研究了聚芳醚酮单体４，４＇－对苯二酚、４，４＇－联苯二酚及４，４＇－二氟苯酮．结果表明，它们的苯环皆存在一定的扭转．首次给出联苯二酚全优化结构，其苯环二面角为５１．８°，活性稍强于对苯二酚，但引入了更多的链支化活性点．含联苯基聚芳醚醚酮的链支化比不含联苯基的ＰＥＥＫ严重，故前者结晶性差．反应机理及实验还表明：前者凝胶化的浓硫酸溶液中存在一种羰基被极化后的红色阴离子．

Monomers of poly(aryl ether ketone)s famiy, such as,4,4'-hydroquinone(PD),4,4'-biphenol(S3)and 4,4'-difluorine benzophenone have been researched by ab initio RHF method. Results obtained show that these monomers have different torques in their aromatic rings.S3 has a dihedral angle of 51.8°,its reactivity is a bit stronger than that of PD, but it introduced more active branching points. Thus, polymer DPEEK from S3 has more serious chain branching and is more difficult in crystallizing than PEEK from PD. And also, it is found that there is a kind of red negative ion in DPEEK solution of concentrated H2SO4.