<scp>ABS</scp> and Styrene‐N‐Phenylmaleimide‐Acrylonitrile Terpolymer Achieved Both Toughening and Boosting Heat Resistance of <scp>PVC</scp>

ABSTRACT The lack of toughness and heat resistance of polyvinyl chloride (PVC) limit its application in construction, transportation, packaging, and medical treatment. In this work, the core–shell structure polybutadiene grafted styrene and acrylonitrile copolymer (PB‐g‐SAN), named (ABS), was utilized to toughen PVC. The composite materials reached the brittle‐ductile transition point at 10 phr. The heat‐resistant modifier styrene‐N‐phenylmaleimide‐acrylonitrile terpolymer (SMIA) synthesized by bulk polymerization was added to PVC/ABS to improve the heat resistance of the composite. The monomer N‐phenylmaleimide with a large spatial site resistance is introduced into SMIA, which restricts the molecular chain movement. There are intermolecular forces between the nitrile group and PVC to enhance the composite compatibility. Phase separation was not observed in the scanning electron microscope images of composites, elucidating the outstanding compatibility of ABS, PVC, and SMIA. The brittle‐ductile transition point was found to be 1350.60 J/m addition of 10 phr ABS. The Vicat softening temperature of the ternary functional composite (PVC/ABS/SMIA, 72:8:20) raised by 2°C, and the initial decomposition temperature increased by 19°C. Furthermore, the impact strength elevated 6 times compared to that of PVC. The toughening and strengthening heat resistance of PVC are realized at the same time.