Abstract

2,2′-Bifuran-5,5′-dicarboxylic acid (BFDCA), a highly promising biobased diacid monomer, was used to modify poly(ethylene terephthalate) (PET) to obtain copolyesters with increased biocarbon content and improved properties compared with PET. Antimony-catalyzed copolymerization of the bifuran and terephthalate 2-hydroxyethyl esters was used to afford the PETBF copolymers. When compared against PET, these random copolymers with 5, 10, or 15 mol % of the bifuran comonomer in the feed (relative to the total amount of the starting esters) showed a slightly elevated glass transition range, higher tensile moduli, enhanced oxygen gas barrier properties, and superior UV blocking while maintaining good transparency otherwise. Based on our results, PETBF copolyesters seem to have promise as materials with enhanced properties that are desirable in advanced packaging applications.