Dynamic mechanical behavior of the dioctyl phthalate plasticized polyvinyl chloride-epoxidized soya bean oil

The mixing of polyvinyl chloride (PVC) with dioctyl phthalate (DOP) shows two stages of gelation and fusion, but the homogeneity of each stage is influenced by the thermal stability of PVC and its rheological behavior. A torque rheometer has been used to gather almost all critical data related to the plasticized PVC in the epoxidized soya bean oil (ESBO). This study shows that, rheological data reflects the effects of DOP and epoxidization levels of SBO, in a DOP plasticized PVC-ESBO. The DOP plasticizer forms a thermodynamically miscible solution with ESBO; that reduces the rate of fusion and torque at balance of PVC. The storage modulus and tan delta of the plasticized PVC-ESBO have been used to show the extent of the homogeneity; but the dynamic mechanical behavior of PVC-ESBO is strongly influenced by DOP and the epoxidization level of SBO. The glass transition temperatures and dynamic properties of DOP plasticized PVC-ESBO are also reported and discussed in terms of the thermal stability and homogeneity of PVC. (C) 2001 Elsevier Science Ltd. All rights reserved.