SI69 is a type of silane coupling agent that is commonly used in rubber compounds to improve their properties. Silica-filled rubber compounds are widely used in tire manufacturing, as they offer improved fuel efficiency, better wet grip, and reduced rolling resistance compared to traditional carbon black-filled compounds.

When SI69 is added to a silica-filled rubber compound, it forms a chemical bond between the silica particles and the rubber matrix. This bond improves the interaction between the silica and the rubber, leading to improved mechanical properties such as tensile strength, tear strength, and abrasion resistance.

Additionally, SI69 can improve the dispersion of the silica particles within the rubber matrix, leading to a more uniform distribution of the filler. This can result in improved compound processing and reduced variability in the properties of the final product.

Overall, the addition of SI69 to silica-filled rubber compounds can lead to significant improvements in their mechanical properties and processing characteristics, making them a preferred choice for tire manufacturers and other applications where high-performance rubber is required.

The modification of the silica surface by reacting it with TESPT (Si69R ) nearly
eliminated the tendency of the silica to form a filler–filler network. It is consumed during the breaking
and re-formation of the filler–filler networks. N110 carbon black shows the highest
tan δ in the 1–10% strain region (Log DSA -2 to -1) that is associated with rolling
resistance. Carbon blacks have less tendency to form a filler–filler network than
silicas, but the agglomerates that do form are relatively weak and break down in
this low strain region. The silica forms more networks, but they are stronger and do
not break until higher strains are applied. The silane-modified silica (Silica-TESPT)
shows very little effect from filler–filler network breakdown and re-formation and
thus less energy consumption than carbon black in the low strain region associated
with rolling resistance.