SYNTHESIS AND RANDOMIZATION OF WELL-DEFINED SEQUENCE, WHOLLY AROMATIC COPOLYESTER ESTERAMIDES

Well-defined sequence, wholly aromatic copolyester/esteramides have been synthesized by an interfacial polycondensation of a preformed triad diacid chloride monomer, di(para-chlorocarbonyl)isophthalate, with the disodium salt of hydroquinone or of deuterated hydroquinone, or with meta-phenylene diamine. Carbon-13 nuclear magnetic resonance (NMR) spectroscopy provided unequivocal evidence for regularly alternating polymer structures, and coupled with statistical methods, for randomization on heating in the case of regularly alternating poly(p-oxybenzoate-co-p-phenyleneisophthalate). Polymers synthesized using standard high-temperature melt-polymerization techniques were shown by statistical/carbon-13 NMR methods to have essentially random structures. Thermal properties of copolymer powders and films were found to vary with monomer sequence distribution as well as with composition. (C) 1994 John Wiley & Sons, Inc.