Reflectance FTIR investigations of the reactions of silanes on silica surfaces

CIR sampling has been used to demonstrate that the antimicrobial silane SiQAC is stable hydrolysis in aqueous solution at near neutral pH values. However, rapid hydrolysis occurs in mildly acidic solutions, but not accompanied by condensation of the silanol groups. After hydrolysis, condensation to form siloxane bonds is rapid in basic solution. The degree of hydrolysis is increased in the presence of silica gel. The silane on silica gel is quite durable towards desorption when contacted with water.