A process for the continuous production of high molecular weight of polybutylene terephthalate

摘要

A process for continuous production of high molecular polybutyleneterephthalate by direct esterification of terephthalic acid and 1,4 butanediol in the presence of tin- or titanium-containing catalysts at preferred temperatures of 235 DEG to 250 DEG C., and preferred pressures of 0.3 to 0.6 bar during the first stage-with minimal formation of tetrahydrofurane-followed by precondensation and polycondensation at reduced pressure.