1,2-Bis(carboxyphenoxy)arylenes and aramids and polyarylates therefrom: synthesis and properties

The synthesis of a new series of aromatic bis(ether acid)s and bis(ether acid chloride)s by fluorodisplacement with catechol or its derivatives has been developed and exemplified. These monomers allow the synthesis of new aramids (poly(ether amide)s), polyarylates (poly(ether ester)s) and copolyarylates in which ortho-phenylene units are enchained through ether linkages. These polymers are significantly more flexible and, therefore, more soluble than conventional aromatic polyamides and polyesters. They have useful levels of thermal stability, associated with relatively high glass-transition temperatures ( > 200 degrees C), are processable from solution or the melt, and are potentially crystallizable. Liquid crystalline poly(ether ester)s were prepared. Polyamides prepared from bis(ether acid)s in which all three aromatic rings, separated by ether linkages, are all ortho-substituted gave low-molecular weight polymers. (C) 1998 Elsevier Science Ltd. All rights reserved.