SYNTHESIS OF SEMI-CRYSTALLINE POLYPHTHALAMIDES THROUGH REACTIVE EXTRUSION OF HEXAMETHYLENE TEREPHTHALAMIDE OLIGOMER WITH LOWER MELTING, SEMI-CRYSTALLINE OR AMORPHOUS POLYAMIDES

摘要

This invention relates to the synthesis of semi-crystalline polyphthalamides (i.e. containing monomeric units of terephthalic acid and hexamethylene diamine) through reactive extrusion of hexamethylene terephthalamide oligomer, or the oligomer of another 6T-rich copolymer, with lower melting semi-crystalline or amorphous polyamides. This process is particularly useful since it is centered around the use of stirred autoclaves for the synthesis of the 6T oligomer and the semi-crystalline or amorphous polyamides which are subsequently combined in a twin screw extruder equipped for devolatilization of water of reaction. It can also be used for the modification of existing semi-crystalline or amorphous polyamides (not necessarily phthalamides) with low levels of 6T.