Preparation of Poly(imide-aramid-sulfone)s and their Thermal Properties

Abstract

A series of poly(imide-aramid-sulfone)s with alternatingly introduced imide/aramid groups were prepared by reacting divinyl sulfone (DVS) and N 1 ,N 4 -bis(4-(vinylsulfonyl)phenyl)terephthalamide (2) with pyromellitic diimide. Three model compounds, N-[2-(p-aminophnenylsulfonyl)ethyl]phthalimide (3), 2,2'-(2,2'-sulfonylbis(ethane-2,1-diyl))diisoindoline-1,3-dione (4), and N,N-bis(4-(2-(1,3-dioxoisoindolin-2-yl)ethylsulfonyl)phenyl)terephthalamide (5), resembling polymers were prepared with good yields by reacting p-aminophenyl vinyl sulfone, DVS, and 2 with phthalimide. Condensation polymerization was carried out by Michael-type addition reaction of the difunctional phthalimide group with the DVS group in the presence of tetrabutylammonium hydroxide (TBAH), resulting in poly(imide-aramid-sulfone)s 6-12 with moderate molecular weights and good yields. They were highly soluble in polar solvents such as N,N-dimethylformamide, dimethylsulfoxide, N-methylpyrrolidinone and tetrahydrofuran. The ratios of DVS/2 were 1/0, 3/1, 2/ 1, 1/1, 1/2, 1/3, and 0/1. Molecular weight and physical properties such as solubility, viscosity, and thermal properties of the polymers were examined.