New catalysts for poly(butylene terephthalate) synthesis. 2. kinetic comparison using model compounds

• Published in: Polymer (Guilford) Vol. 42; no. 18; pp. 7517 - 7522
• Main Authors: BANACH, Timothy E, COLONNA, Martino
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier 01-08-2001
• Subjects: Applied sciences; Exact sciences and technology; Organic polymers; Physicochemistry of polymers; Polycondensation; Preparation, kinetics, thermodynamics, mechanism and catalysts; Mixed catalyst; Catalytic reaction; Rare earth metal complex; Ester polymer; Hafnium complex; Condensation polymerization; Transesterification; Experimental study; Butene terephthalate polymer; Alkoxide; Titanium compound; Kinetics; Activation energy
• ISSN: 0032-3861; 1873-2291
• DOI: 10.1016/S0032-3861(01)00262-2

A kinetic study of polybutylene terephthalate polymerization from dimethyl terephthalate and butanediol, using a catalyst mixture composed of titanium tetrabutoxide and hafnium acetylacetonate, in 1:3 molar ratio, was performed and compared to the standard titanium only catalyst. Arrhenius parameters were obtained from model reactions for both stages of polymerization. The mixed catalyst showed a consistently higher pre-exponential factor and a higher activation energy in the Arrhenius equation compared to the industrially used catalyst. For this reason the mixed catalyst, as observed in actual polymerizations, is more active at high temperature. (Original abstract)