Synthesis and Properties of High Melt Strength Poly(Butylene Succinate)

ABSTRACT Due to the good combined properties, poly(butylene succinate) (PBS) is a biodegradable polymer material with good application potential. Nevertheless, it has the drawback of low melt strength arising from its inherent linear macromolecular structure, which greatly restricts its processing, such as blowing. Multifunctional branching agents can be applied to boost polyester melt strength and improve blowing processability. In this work, the branched PBS was synthesized by introducing various branched agents, such as tartaric acid (TA), citric acid (CA), and pentaerythritol (PER), and their effect on the characteristics was systematically analyzed. Due to the incorporation of branched chains and micro‐crosslinking structures, mechanical characteristics and melt strength of polymers have been improved effectively. PBS‐PER0.1% exhibited tensile strength and elongation at break as high as 50.71 MPa and 347.92%, respectively. Additionally, crystallinity increases with the increase of PER content, which is opposite to the crystallinity of polymer synthesized from other branching agents. Thus, mechanical properties and rheological properties of PBS can be facilely controlled by regulating the chemical structure and content of branching agent.