Synthesis and characterization of new aromatic poly(amide-imide)s derived from 1,4-bis(4-aminophenoxy)-2-t-butylbenzene and various bis(trimellitimide)s

A series of novel t-butyl group-containing poly(amide-imide)s IIIa-m were s ynthesized by the direct polycondensations of 1,4-bis(4-aminophenoxy)-2-t-b utylbenzene (BAP-tBB) with various aromatic bis(trimellitimide)s IIa-m in N -methyl-2-pyrrolidone (NMP) using triphenyl phosphite and pyridine as conde nsing agents. Poly(amide-imide)s III having inherent viscosities between 0. 67 and 1.77 dl g(-1) were obtained in quantitative yields. Most of the resu lting polymers were readily soluble in polar solvents such as NMP and N,N-d imethylacetamide. All of the soluble poly(amide-imide)s afforded transparen t, flexible, and tough films. The glass transition temperatures of the-se p olymers were in the range of 243-300 degrees C, and the 10% weight loss tem peratures were above 490 degrees C in nitrogen. The properties of poly(amid e-imide)s III were compared with those of the corresponding poly(amide-imid e)s III' prepared from the bis(trimellitimide) of BAP-tBB and various aroma tic diamines. (C)2000 Elsevier Science S.A. All rights reserved.