The mechanism of silica sol as a binder

Chemical bonding

The main component of silica sol is nanoscale silica (SiO ₂) colloidal particles, with a surface rich in silanol groups (Si OH). During the curing process, silanol groups form silicon oxygen bonds (Si-O-Si) through dehydration condensation reactions, constructing a three-dimensional network structure. This chemical bonding cooperation forms a strong chemical connection between the silica sol and the surface of the adhesive, significantly improving the bonding strength.

Physical adsorption and mechanical interlocking

The nanoscale colloidal particles of silica sol have a high specific surface area and can penetrate into the micropores and cracks on the surface of the adhesive, enhancing adhesion through physical adsorption. After solidification, the dense structure formed by the silica sol exhibits a mechanical interlocking effect with the surface of the adhered material, further enhancing the adhesive stability.

High temperature resistance and chemical corrosion resistance

The bond energy of Si-O-Si is relatively high (about 466 kJ/mol), which makes the silica sol adhesive have excellent high temperature resistance (able to withstand high temperatures of 600-1000 ℃) and chemical corrosion resistance (such as acid resistance, alkali resistance, and organic solvent resistance), suitable for bonding needs in extreme environments.