Light-Colored and Organosoluble Fluorinated Polyimide Derived from 1,2,3,4-Cyclobutanetrtracarboxylic Dianhydride

Abstract

The alicyclic dianhydrides 1,2,3,4-cyclobutanetrtracarboxylic dianhydride was polymerized with four kinds of fluorinated aromatic diamine, 1,4-bis(4-amino-2-trifluoromethyl phenoxy)diphenyl, 1,4-bis(4-amino-2-trifluoromethylphenoxy) diphenyl ether, 2,2-bis[4-(4- aminophenoxy)phenyl]hexafluoropropane and 2,2-bis[4-(4-amino-2-trifluoromethylphenoxy) phenyl]sulfone respectively, via a two-step polycondensation procedure to prepare four series of fluorinated polyimides(PIs). The PI films exhibited high optical transparency in the visible light region(400-700nm) with the transmittance higher than 80% at 450nm. Especially, the PI-III containing four CF3 group showed the best optical transparency with the transmittance higher than 84.61%. And the PI films showed little absorption at the optocommunication wavelengths of 1.30µm and 1.55µm. In addition, these PIs were soluble in amide-type solvent, even in less polar solvent. The effect of internal linkage group of fluorinated diamine on the solubility of PIs was similar.