Bio-oil based plasticizers have gained great attention in rubber industry as alternatives of petro-based plasticizers with high content of polycyclic aromatic hydrocarbons. In this work, five fatty acid benzyl esters were synthesized by the esterification of fatty acids (lauric acid, myristic acid, palmitic acid, stearic acid, and oleic acid, which are obtained after hydrolysis of some vegetable oils) with benzyl alcohol. They were further applied as plasticizers in silica-filled solutionpolymerized styrene-butadiene rubber/butadiene rubber (SSBR/BR) composites in order to study the structure-property relationship, compared with treated distillate aromatic extract (TDAE) as standard. The composites were studied for their processability, curing, static, and dynamic mechanical properties by developing through compatibility between bio-plasticizers and polymer matrix. The results show that benzyl laurate with suitable hydrocarbon chain length and benzyl oleate with a carbon-carbon double bond have comparatively improved performance compared to TDAE in the silica-filled SSBR/BR composites.

As commercial rubber in tires, silica-filled solution-polymerized styrene-butadiene rubber/butadiene rubber (SSBR/BR) compounds exhibited preferable wet skid resistance (WSR) properties, which could be further enhanced by the incorporation of some oligomeric resins. However, the untreated dicyclopentadiene (DCPD) resin shows a slight improvement in wet friction even if the good compatibility between DCPD and SBR owing to their common cyclic structures. For this problem to be addressed, we aimed to enhance its resin-silica interaction by reaction with maleic anhydride (MAH). In detail, the effect of MAH content on WSR, curing characteristics, physical-mechanical properties of the silica-filled SSBR/BR composites was investigated. When the MAH content is 4 wt% in the modified DCPD resin, the maximum enhancement of about 15% in tan δ values at 0 °C, as well as that of 17% in British pendulum skidding tester (BPST) index is obtained, indicating a desirable improvement in WSR. In addition of these two commonly used methods, water contact angles of the vulcanizates increase gradually with increasing MAH content, further confirming the remarkable performance of modified DCPD resin in WSR.