Process for the preparation of polyesters having stabilized melt viscosity in the presence of aromatic poly(carbonates)

摘要

The melt viscosity of high molecular weight linear polyesters is stabilized in the presence of aromatic (poly-)carbonates by adding a minor proportion of a non-volatile monofunctional ester-forming compound to a mixture of glycol and terephthalate or isophthalate reactants and heating the resulting mixture. The products of the process are suitable for conversion to compositions with aromatic (poly-)carbonates, especially flame retarded such compositions, where stabilized melt viscosity during fabrication is critical.