Synthesis of High Injection Molding Performance and Low Acetaldehyde Poly(Ethylene Terephthalate) by Eco-Friendly and Highly Active Titanium Catalyst

Abstract

In this paper, ECO-friendly titanium magnesium catalyst with high activity was synthesized, and titanium based bottle polyester was synthesized on a 30,000 ton annual industrial plant. At the same time, the characterization and processing properties of titanium based and antimony based polyester were studied. Compared with commercial antimony based polyester, TMPC chips had faster SSP rate and lower AA content, easier crystallization and high catalyst activity, easy to form macromolecular chains, and the rheology of polyester melt also showed a wider processing range. However, the chain end thermal degradation reaction of titanium based bottle chips was slightly larger than that of antimony based bottle chips, and the α transition temperature in DMA test also led to the molecular chain motion of titanium bottle chips is more easily affected by temperature, which was not conducive to maintaining a better viscosity drop and AA value of bottle preform for a long time in the high-temperature injection molding process. To sum up, according to the performance test results, by using TMPC catalyst and adjusting the processing conditions to control the injection molding process of TMPC polyester, titanium bottle preform with better viscosity drop and AA content can be obtained. Finally, the bottle preform with a weight of 28.5g was prepared by using titanium TMPC bottle chips. The injection molding processing temperature was reduced by 10 °C, the viscosity drop was equivalent to that of commercial antimony bottle preform, the end carboxyl group was reduced by 54%, the color index b value was reduced by 17.3%, and the AA content was reduced by 19.8%.