Graft modification of polyvinyl chloride with epoxidized biomass-based monomers for preparing flexible polyvinyl chloride materials without plasticizer migration

Cardanol glycidyl ether, epoxidized acetylated castor oil methyl ester, and epoxidized soybean oil were grafted on polyvinyl chloride (PVC) chains to obtain flexible PVC materials. The structure and properties of graft modification of PVC materials were investigated. The glass transition temperature of graft modification of PVC with cardanol glycidyl ether, epoxidized acetylated castor oil methyl ester, and epoxidized soybean oil was 42.1 °C, 43.8 °C, and 37.9 °C, respectively. The mechanical properties illustrated that graft modification of PVC materials were more flexible than PVC. The extraction tests showed that the modified PVC materials presented no migration in n-hexane and can be used to prepare flexible PVC products with high requirements of durability. The internal plasticizing mechanism was also discussed according to the free volume theory.