Alternate copoly(amide-imide) was synthesized from two aromatic diamines and trimellitic anhydride (TMA). When the diamine was mphenylenediamine (m-PDA), the resulted poly(amide-imide) [P(A-alt-I)] was found to be of light colour. Specifically, when m-PDA was located between two amide groups in the P(A-alt-I) chain, the P(A-alt-I) was colourless. Using triphenyl phosphite (TPP) and pyridine as condensing agents, a series of P(A-alt-I)s (series III) containing m-PDA was synthesized through direct polycondensation of an aromatic dicarboxylic acid (II b) prepared from m-PDA and TMA, as well as various aromatic diamines. The isomeric series of P(A-alt-I)s (series IV) was synthesized from diacid monomers that had been prepared from various diamines and TMA, as well as m-PDA. The colour (yellow) of P(A-alt-I)s IV was lighter than that of the isomeric series of P(A-alt-I)s III. The 24 P(A-alt-I)s (series III and series IV) had inherent viscosities ranging 1.01–1.88 dl g ¹1. The tensile strengths, elongations to break and initial moduli of the films were 86–112 MPa, 6%–42% and 1.74–2.81 GPa, respectively, and most of the films had yielding. Polymers of Series IV had glass transition temperatures 228°C–293°C, which were higher than those of Series III ranging 223°C–278°C. The 10% weight loss temperatures in nitrogen of these two series were similar in the range 472°C–561°C.
Посилання на статтю:
Preparation and characterization of colourless alternate poly(amide-imide)s based on trimellitic anhydride and m-phenylenediamine / Chin-Ping Yang, Ruei-Shin Chen // Polymer. – 1999. – N 40. – P. 1025–1034.