A kinetic study of the hydrolytic degradation of polyethylene terephthalate at high temperatures

摘要: The hydrolytic depolymerization of molten PET in excess water was studied using a 2 L stirred pressure reactor at temperatures 250, 265, and 280°C. Rate constants for hydrolysis are calculated from the initial rate data. At water: charge ratios (w/w) exceeding 5.1, essentially complete to monomer is possible 265°C. lower charges, an equilibrium established. g water/g three temperatures. A kinetic model proposed describe reaction. shown fit experimental data yield good predictions concentration carboxyl groups. Carboxyl-group concentrations measured end-group analysis technique. Potentiometric titrations carried out one two solvent systems, dimethylphenol:chloroform or dimethylsulfoxide, depending on extent hydrolysis. © 1993 John Wiley & Sons, Inc.