REAXIS® C248VM (Dibutyltin Oxide + Silane) is a liquid version of dibutyltin oxide (DBTO) containing vinyltrimethoxy silane (VTMO), which is commonly used as a catalyst for silicone chemistries. REAXIS® C248VM contains 50% of the active tin catalyst content compared to the solid version of REAXIS® C248. Other silane grades include REAXIS® C248T (DBTO+ tetraethylortho silane/TEOS) and REAXIS® C417 (DOTO + tetrapropylortho silane/TPOS). Liquid versions of REAXIS® C248 utilizing phthalates as a non-reactive diluent include REAXIS® C248DP and REAXIS® C248DN. Other liquid grades are available upon request.
|Tin Content (%)
|31.1 - 35.1
|Color (Gardner Number)
|1.2 - 1.4
REAXIS® C248VM and its alternatives can be used as a homogeneous catalyst in a wide spectrum of silicone applications including adhesives, sealants, and elastomers. Silicone-based applications include: acetoxy-, ethoxy- and oxime-based Room Temperature Vulcanizing (RTV) adhesives and sealants, polyethylene crosslinked silanes (PEX), and select silane modified polymers (SMPs).
Given its high tin content, liquid form, and good compatibility with a wide range of raw materials, REAXIS® C248VM tends to be a highly reactive catalyst across a broad range of silicone formulations. In regard to silicone reactions, REAXIS® C248VM, like all tin-based catalysts, will catalyze the silanol/silane condensation reaction,acting as both a polymerization and crosslinking catalyst. REAXIS® C248VM is hydrolytically stable within typical formulation moisture levels, but this stability will break down with increasing moisture content.
REAXIS® C248VM should be stored in the original packaging at moderate temperatures. The container should be closed tightly after each use to maximize shelf life. Given the presence of a silane, hydrolytic instability could occur resulting in reduced catalytic performance.