SiSiB® PC2320 is a mercapto-functional silane that finds use as a coupling agent in polysulfide and polyurethane caulks and sealants. It is especially useful in sulfur-cured and metal oxide-cured elastomers. Chemically bonding reinforcing minerals like silica, clay, mica and talc to the polymer matrix, properties including modulus, tensile and tear strength, heat buildup, abrasion resistance, resilience, compression set and cure time are improved in mineral-filled elastomers. It can be used as a pretreatment on minerals or added at the time of compounding. Being a rather efficient and fast sulfur containing silane, typically lower silane loading levels are used.