Preparing polyester monomer and/or polyester oligomer, comprises stripping a reaction mixture made of polyester raw material and a diol with water vapor, where an alcohol is formed by hydrolysis and escapes into a vapor phase

摘要

Preparing polyester monomer and/or polyester oligomer, where an ester of at least a dicarboxyl or a mixture of at least a dicarboxyl and its ester is used as polyester raw material, comprises stripping a reaction mixture made of the polyester raw material and at least a diol at increased pressure and temperature, which is sufficiently high for an hydrolysis of dicarboxyl ester, with water vapor, where an alcohol is formed by hydrolysis and escapes into a vapor phase, and a reaction product (2), which contains diol and polyester monomer and/or polyester oligomer, is removed as liquid phase.