The torque development during vulcanization in silica-filled compounds is not only influenced by the crosslinking density but also by filler–filler interactions, silane-mediated reactions and by interactions of the silica with accelerators. This study quantifies these contributions by determining Mooney viscosity, filler flocculation rate, bound rubber content, and crosslink density. Compounds containing functionalized and non-functionalized SSBRs at varying silica loadings with and without silane were investigated. The results show that polymer crosslinking dominates cure torque at low filler loadings, while filler-related interactions prevail at high silica contents, indicating that cure torque cannot be directly correlated with crosslink density in highly filled silica compounds.

• The fundamentals of vulcanization and its role in rubber strength, elasticity and durability
• The limitations of traditional compression molding in rubber vulcanization
• How microwave-assisted vulcanization serves as an efficient alternative to conventional methods
• How microwave-assisted vulcanization improves cure uniformity in rubber materials
• The potential of microwave vulcanization for silica-filled SSBR tire tread compounds