EFFECT OF SOYBEAN OILS WITH VARIOUS UNSATURATION LEVELS ON CARBON BLACK-FILLED EPDM RUBBER VULCANIZED WITH PEROXIDE

摘要

Soybean oil(SBO)can be used in a limited amount as a sustainable processing oil in ethylene-propylene-diene monomer(EPDM)rubber compounds along with petroleum-based paraffinic oil(PO).Being highly unsaturated,SBO takes part in the cross-linking reaction in both sulfur-and peroxide-cured EPDM systems.The replacement of PO with SBO causes a decrease in crosslink density,tensile strength,and modulus and leads to increased elongation and poorer resistance to compression.In this study,the mechanical and viscoelastic properties of peroxide-cured EPDM rubbers filled with carbon black and formulated with soy-derived plasticizers having reduced iodine values were studied and compared to the properties of PO-based rubber.The soy-derived plasticizers studied in this work are high oleic soybean oil,partially hydrogenated SBO,and completely hydrogenated SBO.It was found that soy-derived plasticizers can partially substitute for the petroleum-based plasticizer in EPDM compounds with a minimal impact on properties.The level of unsaturation and the degree of substitution can be adjusted depending on the requirements for specific applications.