Monofilaments of isosorbide-based tetrapolyesters with enhanced (bio)degradability prepared by a solid-state drawing process: Synthesis and struture-property relations

To enhance the degradation rate of poly (butylene adipate-co-terephthalate) (PBAT) in the natural environment and to investigate the effect of modified monomers on the molding and structure of copolyester fibers, a series of isosorbide modified PBAT (PBIAT) tetrapolyesters were synthesized and monofilaments were prepared by solid-state drawing in this work. The experimental results revealed that the introduction of isosorbide formed a partial block structure in the molecular chain, and that a significant improvement in the properties of heat resistance and degradability of the copolyester was observed with the introduction of isosorbide. In the research of fiber forming and structure-property relationship by isosorbide, it was found that although the monofilament orientation process was affected by the V-shape structure of isosorbide, the change of the crystal structure under stress was similar to that of polybutylene terephthalate (PBT). The PBIAT monofilaments showed a decrease in the strength at break affected by the introduction of isosorbide but they still met the requirements for textile applications.