Effect of the thermodynamic affinity of plasticizers for polyvinyl chloride on the heat of its interaction with fillers

Abstract

A microcalorimeter of the Calvé type has been used to determine the heats of swelling of PVC in four plasticizers and heats of wetting by the latter of chalk, kaolin and Aerosil and the heats of the interaction of plasticized PVC with these fillers. It is shown that the energy interaction of PVC with the filler is due to the competing influence of its heats of swelling in the plasticizers and the heats of wetting by the latter of the fillers. For identical thermodynamic affinity of the plasticizers for PVC the global thermal effect of the interaction of plasticized PVC with filler is more negative the greater the heat of wetting by the plasticizer of the filler. For identical heats of wetting by the plasticizers of the PVC filler the worse PVC interacts energetically with the filler, the greater the thermodynamic affinity of the plasticizer and the greater the heat of swelling of PVC.