Jojoba Oil (Simmondsia Chinensis) As A Natural Plasticizer For Ethylene Propylene Diene Monomer Elastomers

Jojoba oil (JO) as a natural plasticizer for ethylene propylene diene monomer (EPDM) rubber was studied and compared with paraffin oil (PO) at 5, 10, and 20 phr, using sulfur and peroxide cross-linking systems. Vulcanization curves for sulfur systems had the lowest torque value for JO, 26 dNm, whereas for PO, it was 60 dNm. For peroxide systems, the lowest torque value was for PO compounds, 18 dNm, whereas for JO, it was 21 dNm. Stress values for sulfur systems were 12-18 MPa, and for peroxide systems, 14-23 MPa; 23 MPa was for JO compounds. Highest cross-link density values were for sulfur systems with PO >1000 mol/m(3). Thermogravimetric analysis indicated volatilization of PO, 250-280 degrees C and for JO at 400 degrees C, evidencing better EPDM thermal stability with JO. Results showed a greater plasticizing effect of JO when using sulfur as the cross-linking agent, and its possible use as a renewable plasticizer for EPDM, reducing the concentration of the plasticizer in formulations.