Preparation and properties of novel fluorinated polyimides based on 2,2′,6,6′-tetrafluorobenzidine

✍ Scribed by Hong-Jie Xu; Jie Yin; Yin He; Jian-Hua Fang; Zi-Kang Zhu; Zong-Guang Wang

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 136 KB
• Volume: 70
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/(sici)1097-4628(19981121)70:8<1605::aid-app18>3.0.co;2-3

✦ Synopsis

Fluorinated polyimides were prepared from 2,2Ј,6,6Ј-tetrafluorobenzidine and four conventional dianhydride monomers by a solution polycondensation reaction followed by a chemical imidization. Polyimide based on 2,2Ј,6,6Ј-tetrafluorobenzidine and hexafluoroisopropylidene bis(3,4-phthalic anhydride) (6FDA) is soluble in organic solvents such as NMP, DMA, DMF, THF, chloroform, and acetone while those based on 2,2Ј,6,6Ј-tetrafluorobenzidine and pyromellitic dianhydride (PMDA), benzophenone-3,3Ј,4,4Ј-tetracarboxylic acid dianhydride (BTDA), diphenylether-3,3Ј,4,4Ј-tetracarboxylic acid dianhydride (ETDA) are not. Polyimide from 2,2Ј,6,6Ј-tetrafluorobenzidine and 6FDA possesses high optical transparency at 350 -700 nm and has a in-plane refractive index of 1.558 at 632.8 nm. All polyimides exhibit glass transition temperatures above 350°C. They also possess very high thermal stability.