Effects of poly(butylene succinate) and calcium carbonate on the physical properties of plasticized poly(vinyl chloride)

Abstract

In this studypoly(butylene succinate) (PBS) , a polymeric plasticizer,  was partially replaced a conventional plasticizer, diisononyl phthalate (DINP) to avoid the plasticizer loss from poly(vinyl chloride) (PVC) overtime for various service conditions and to obtain a long-term plasticizer retention in the flexible PVC products. The plasticized PVC samples were prepared by melt mixing on a two roll mill, followed by compression molding. The mechanical properties (tensile properties, tear strength and hardness), thermal stability and morphology of the 20/20 phr (parts by weight per hundred parts of resin) DINP/PBS-plasticized PVC were evaluated and compared with those of the 40 phr DINP-plasticized PVC. The tensile strength, Young’s modulus, tear strength, hardness and thermal stability were found to be improved, while the elongation at break was decreased as a result of the partial replacement of DINP with PBS in the plasticized PVC. Moreover, the DINP/PBS-plasticized PVC composites filled with varied loadings of CaCO₃ (2.5, 5, 7.5 and 10 phr) showed an increase in the elongation at break, Young’s modulus and thermal stability in a dose-dependent manner, while the tensile strength, tear strength and hardness were unaffected by the increasing amount of CaCO₃. The morphology of the composites observed by scanning electron microscopy showed a number of voids on the fractured surface of the plasticized PVC due to the pulling out CaCO₃ particles, caused by the low interfacial adhesion between filler and polymer.