Benzyl Esters of Vegetable Oils as Processing Oil in Carbon Black–Filled SBR Compounding: Chemical Modification, Characterization, and Performance

ABSTRACT Three different types of benzyl ester were synthesized from vegetable oils (i.e., coconut oil, palm oil, and soybean oil). They were then utilized in styrene butadiene rubber (SBR) compound reinforced with carbon black. First, the benzyl esters were investigated by varying the molar ratio of fatty acids in vegetable oil to benzyl alcohol, the catalyst concentration, the reaction time, and the reaction temperature, observing the yield of benzyl ester. Then SBR was compounded with the benzyl esters, observing cure characteristics, mechanical properties, and morphologies of the SBR compounds, with the control compound containing conventional aromatic oil. The highest 96% yield of benzyl ester was obtained with palm oil fatty acid. Furthermore, the benzyl ester oils consumed less energy during processing but gave comparable carbon black dispersion, in comparison with the conventional aromatic oil.