Synthesis of Spinnable Poly(ethylene terephthalate-co-glycolate) with Enhanced Degradability

The disposal of postconsumer textiles has a significant impact on environmental sustainability. Herein, we have developed a spinnable poly(ethylene terephthalate) (PET) based copolyester, poly(ethylene terephthalate- co -glycolate) (PET-GA), which possesses both good usability and biodegradability for fabrics. The copolymerizations of ethylene glycol, terephthalic acid, and glycolic acid catalyzed with stannous octanoate, tetrabutyl titanate (TBT), ethylene glycol antimony, and antimony trioxide were investigated. The copolyester chain structures and their thermal property, rheological performance, and spinnability were characterized, and the mechanical properties and degradability of the copolyester fibers made by a melt spinning together with a post-stretching were evaluated. We found that TBT at 0.004 mol % of the total acid group was suitable for synthesizing PET-GAs with good usability and degradability. The filament yarns exhibited excellent performance with breaking strength up to 3.70 cN/dtex and dyeability by using a conventional polyester dyeing process. In addition, enhanced degradability was observed in both an alkali hydrolysis and a composting experiment. The PET-GA fibers degraded 15.8 times faster than PET fibers, while 40.4 wt % of the PET-GA fibers was biodecomposed by microorganisms in 140 days. Such copolyester fibers are believed to be beneficial for their recycling, making them a promising solution for the textile waste problem.