Crystallization and rheological properties of long-chain branched PBS polyesters and effect on multifilament properties

Poly(butylene succinate) (PBS) is a biodegradable material widely used in the field of plastic parts and films. However, its weak molecular entanglement limits its development in several fields, e.g., fibers. To address this issue, in this study, the relationship between macromolecular entanglement and branching structures on the crystallization and rheological properties of PBS were investigated. Both strategies strongly affect the performance of PBS by influencing its crystallinity and crystallization rate, spherulite growth and morphology. The decrease of spherulite growth is about 15 μm s −1 at 85°C of the modified long-chain branched PBS. The structure also has a major influence on the rheological properties of the polymer: the network structure of the branched modified polyester makes PBS exhibit higher melt elasticity, which expands the processing window of PBS. Based on previous research, PBS multifilament were prepared by melt spinning. The existence of branched structure can significantly improve the performance of PBS fibers, the strength of PBS-POY fiber can reach 1.62 cN dtex −1 , but it shows greater thermal stress value. This provides a new route for the preparation of degradable PBS fibers.