Novel synthesis, characterization and application of dibutyrate bis(2-hydroxyethyl) terephthalamide as a plasticizer in PVC compounding

This study focuses on the synthesis and application of dibutyrate of bis(2-hydroxyethyl) terephthalamide (DB-BHETA) as a plasticizer in poly(vinyl chloride) (PVC) compounding. DB-BHETA was synthesized from poly(ethylene terephthalate) bottle waste through aminolysis followed by condensation reaction with butyric acid. Synthesized DB-BHETA was characterized by FTIR, DSC and NMR. Plasticized PVC was prepared by melt blending of PVC in different ratios with DB-BHETA and the mechanical, thermal and rheological properties were investigated. The glass transition temperature (Tg) decreased with increasing concentration of DB-BHETA, confirming its plasticizing effect. The impact properties of PVC/DB-BHETA were maximum at weight ratio of 80/20. Shore hardness continuously reduced with increase in the concentration of DB-BHETA in PVC. Also, incorporation of DB-BHETA results in a gradual decrease in the loss modulus (viscous) and an increase in the storage modulus (elastic).