Syntheses and properties of organosoluble polyamides and polyimides based on the diamine 3,3-bis[4-(4-aminophenoxy)-3-methylphenyl]phthalide derived from o-cresolphthalein

Diamine 3,3-bis[4-(4-aminophenoxy)-3-methylphenyl]phthalide (BAMP) was deri ved from the o-cresolphthalein, and then it was polycondensated with variou s aromatic dicarboxylic acids and dianhydrides to synthesize polyamides (PA s) and polyimides (PIs), respectively. PAs have inherent viscosities of 0.7 8-2.24 dL/g. Most of the PAs are readily soluble in a variety of solvents s uch as DMF, DMAc, and NMP and afforded transparent and tough films from DMA c solutions. The cast films have tensile strengths of 75-113 MPa as well as initial moduli of 1.71-2.97 GPa. These PAs have glass transition temperatu res (T(g)s) in the range of 242-325 degrees C, 10% weight loss temperatures occur up to 473 degrees C, and char yields are between 57 and 64% at 800 d egrees C in nitrogen. PIs were first synthesized to form polyamic acids (PA As) by a two-stage procedure that included a ring-opening reaction, followe d by thermal or chemical conversion to polyimides. Inherent viscosities of PAAs are between 0.71 and 1.63 dL/g. Most of the PIs obtained through the c hemical cyclodehydration procedure are soluble in NMP, o-chlorophenol, m-cr esol, etc., and they have inherent viscosities of 0.58-1.32 dL/g. T(g)s of these PIs are in the range of 270-305 degrees C and show 10% weight loss te mperatures up to 477 degrees C. PIs obtained through the thermal cyclodehyd ration procedure have tensile strengths of 72-142 MPa, elongations at break of 8-19%, and initial moduli of 1.80-2.72 GPa. (C) 1999 John Wiley & Sons, Inc.