Dynasylan SILBOND 40-HF is a clear, low-viscosity liquid with a minimum silica content of 40.0% (the Si content of Dynasylan SILBOND 40-HF is calculated as SiO2) and a flash point above 100° F (38° C), classifying it as a combustible liquid. This product is available to customers requiring a higher flashpoint than Dynasylan SILBOND 40.
Dynasylan SILBOND 40-HF is an ethyl polysilicate that is the partially hydrolyzed product of tetraethyl orthosilicate (TEOS). The partial hydrolysis of TEOS (Si[OEt]4) results in the conversion of ethoxy groups to hydroxyl groups forming silanols. Subsequent condensation of silanols will form siloxane bonds (-Si-O-Si-O-) and eventually cause the material to gel.
Dynasylan SILBOND 40-HF is immiscible with water, therefore hydrolysis requires a cosolvent as a solubilizer. Mineral acids and ammonia are suitable as catalysts.
Dynasylan SILBOND 40-HF or its hydrolysates are also the binder component for 1- and 2-pack inorganic zinc-rich coatings, for corrosion protection on steel, and for slurries used in precision investment castings.