Low Polycyclic Aromatic Hydrocarbon Process OIL in Butadiene Rubber Compound for Tire Tread Application

The role of process oil in rubber compounding is well established. One of the main purpose is to manage viscosity of rubber mixes particularly filled compound in order to maintain efficient processability. For tire application, new legislation (EC18/08/2006) stipulated that the oil used must not exceed 3% of polycyclic aromatic hydrocarbon (PAH) content and this regulation are now in force. This has forced rubber industries especially tire manufacturers to replace Distillate Aromatic Extract (DAE) with alternative which can comply to this regulation while maintaining similar performance. Extensive studies were performed in the last decade and found Treated DAE (TDAE) are able to comply with this regulation and has been accepted by rubber industries as alternative to standard aromatic oil. However, DAE and TDAE are derived from Group I base oil which its supply are increasingly limited due to closures of many Group I base oil production in favor of more economical Group II and III production. Therefore, it is expedient to investigate alternative oil comparable to TDAE in term of mixing, vulcanization and performance. While most of previous studies focused profoundly on SBR and NR compound, this work concentrated more on BR compound considering its importance in tire application. This study report the effect of alternative oil on rubber mixing and vulcanization characteristic as well as its effect of mechanical properties such as hardness, heat build-up, tensile properties and dynamic mechanical behavior. It was found that alternative oil performance are comparable to TDAE.