Efficiency Increase of Poly(ethylene terephthalate-co-isosorbide terephthalate) Synthesis using Bimetallic Catalytic Systems

New catalytic systems are developed to increase the transesterification efficiency during the synthesis of poly(ethylene terephthalate-co-isosorbide terephthalate) with the aim of compensating for the lack of reactivity of the isosorbide and to reduce the coloration of the polymer. The combination of antimony oxide with a second metal (lithium-, magnesium-, or aluminium-based compounds) is investigated, leading to the discovery of innovative antimony-based bimetallic catalytic systems that exhibit a higher polymerization efficiency, even at high isosorbide contents (20%) and, in some cases, lower coloration.