Synthesis and characterization of new soluble cardo polyamides containing the tricyclo[5.2.1.0(2,6)] decane group

A new cardo dicarboxylic acid, 8,8-bis[4-(4-carboxyphenoxy)phenyl]tricyclo[ 5.2.1.0(2,6)]decane (BCPTD), was synthesized from 4,4'-(octahydro-4,7-metha na-5H-inden-5-ylidene)bisphenol and p-fluorobenzonitrile via aromatic nucle ophilic substitution followed by hydrolysis. A series of new cardo polyamid es was prepared by the direct polycondensation of BCPTD and various aromati c diamines in N-methyl-2-pyrrolidinone (NMP) with triphenyl phosphite and p yridine as the condensing agents. Polymers were produced with moderate to h igh inherent viscosities of 0.65 to 1.08 dL g(-1). The polymers, except for polymer PAI, exhibited number-average molecular weights and weight-average molecular weights in the range of 38,400 to 86,300 and 57,800 to 148,000, respectively. Nearly all of the polymers were readily soluble in polar solv ents such as NMP, N,N-dimethylacetamide, N,N-dimethylformamide, and dimethy l sulfoxide as well as in less polar solvents such as pyridine, gamma-butyr olactone, and tetrahydrofuran. Al of the polymers were amorphous, and the p olyamide films had a tensile-strength range of 75 to 128 MPa and a tensile- modulus range of 2.0 to 2.8 GPa. These polyamides had glass-transition temp eratures between 240 and 269 degrees C and 10% weight-loss temperatures in the range of 477 to 508 degrees C and 471 to 518 degrees C in nitrogen and air atmospheres, respectively. (C) 2000 John Wiley & Sons, Inc.