Synthesis of alternating polyamide esters by melt and solution polycondensations of N,N′-Di(6-hydroxycaproyl) diamines and N-6-hydroxycaproyl aminoalcohol with terephthalic and adipic dimethyl esters and dichlorides

Abstract

Alternating polyamide esters of structures A and B were obtained by melt polymerization of dimethyl adipate and terephthalate or by solution polymerization of adipoyl and terephthaloyl chlorides, with N,N′-di(6-hydroxycaproyl)diamines and an N-6-hydroxycaproyl aminoalcohol: where R1 is selected from dimethylene, hexamethylene, and p-phenylene radicals, and R2 is selected from tetramethylene or p-phenyl radical. Polyamide esters of structure A′ were also prepared: Average values of melting points of the resulting polyamide esters were dependent on the starting diacid derivatives, amide diols, and methods of polymerizations as follows: where CPZ, CHD, CED, and CPPD are N,N′-di(6-hydroxycaproy1)-, each in this order: piperazine, hexamethylenediamine, ethylenediamine, and p-phenylenediamine. ECA is N-(2-hydroxyethyl)6-hydroxycaproamide. For a given polyamide ester obtained from the same starting materials and by the same method of polymerization, the melting points increased with inherent viscosities. Polyamide esters of high molecular weight were obtained from CHD with both adipic and terepbthalic derivatives both by melt and solution polymerizations. Polymerizations of the other amide diols gave lower molecular weights. Solution polymerization gave colorless or light-colored polymers, while melt polymerization gave deeper-colored polymers.