TOWARD REPLACEMENT OF PETROLEUM OILS BY MODIFIED SOYBEAN OILS IN ELASTOMERS

Precipitated silica-and carbon black (CB)-filled styrene-butadiene rubber (SBR) compounds and vulcanizates containing naphthenic oil (NO), soybean oil (SO), and modified soybean oil (MSO) were studied. Gel fraction; crosslink density; bound rubber fraction; curing behavior; and thermal, mechanical, and dynamic properties were compared. Interaction between SO, MSO, and silane coupling agent was also studied. It was shown that the incorporation of SO and MSO had similar effects in both silica-and CB-filled SBR compounds and vulcanizates. SO and MSO were found to consume curatives leading to a lower crosslink density and improved thermal stability of compounds and vulcanizates. In comparison with NO, MSO was found to increase the elongation at break and tensile strength, and the values of tan delta at 10 degrees C and 60 degrees C predict an increase of the wet traction performance and the rolling resistance to decrease the modulus and abrasion resistance. After adjusting the recipe, the modulus and abrasion resistance of the silica-and CB-filled SBIVMSO vulcanizates were tremendously increased, and the silica-filled SBR/MSO vulcanizates exhibited a better wet traction performance, a lower rolling resistance, and a better abrasion resistance simultaneously than the silica-filled SBR/NO vulcanizate.