SYNTHESIS AND CHARACTERIZATION OF NEW POLYAMIDES DERIVED FROM 1,6-BIS[4-(4-AMINOPHENOXY)PHENYL]DIAMANTANE

A series of new polyamides 3 were synthesized by direct polycondensati on of the 1,6-bis [4-(4-aminophenoxy)phenyl] diamantane (1) with vario us dicarboxylic acids. The polyamides had inherent viscosities of 0.45 -1.90 dL/g and number-average molecular weights (M-n) of 24,000-110,00 0. Dynamic mechanical analysis (DMA) reveals that polymers 3 have two relaxations on the temperature scale between - 100 and 400 degrees C. Their cu relaxations occurred at high temperatures, ranging from 338 t o 389 degrees C. Moreover, these polymers remained quite stable at hig h temperatures and maintained good mechanical properties (G' = ca. 10( 8) Pa) up to temperatures close to the main transition markedly exceed ing 350 degrees C. Due to the bulky diamantane elements and the flexib le ether segments, the polymers 3 were amorphous and soluble in a numb er of organic solvents such as pyridine, N-methyl-2-pyrrolidone (NMP), and N,N-dimethylacetamide (DMAc). The polyamides 3 have tensile stren gths of 56.7-90.2 MPa, elongation to breakage values of 7.5-27.7%, and initial moduli of 1.8-2.1 GPa. (C) 1998 John Wiley & Sons, Inc.