Polyimides PI, PEI, or PAI

Polyimides (PI) have imide group, -R-N = (CO)2 = R -, in the main chain. Owing to a variety of possible R and R groups, their Tg = 180-420 °C. To improve 

PAI with 0.1-50 wt% of either PSF, PA, or PARA Improved melt flow and good mechanical properties Toray Industries, Inc. 1979,1980, 1981 

PES/PPBA (Tg = 200-300 °C) For lacquers and homogenous, clear films Patton and LaMarre 1983 

PEI with PSF, PP, PEC, or PAr with PC and PEST, PAr or PA, etc. For good processability, improved flexural and impact strength Giles, 1983, 1984 

PI with 0.01-10 phr PSF solution cast For films with good blocking resistance Mitsubishi Chem., 1984 

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