The kinetics of silylation of hydroxylated silica II CPG-10 porous glasses

 The kinetics of chemisorption of trimethylchlorosilane, trimethylbromosilane, and triethylchlorosilane on samples of porous silica, CPG-10 porous glasses, of varying pore diameter were investigated and found to follow a first-order kinetics law in which the reaction is retarded by one of its products. At constant temperature, the rate was found to increase with increasing diameter of the pores in the range used. Increasing the molecular cross-sectional area of the adsorptive, the silane molecule, in the range 0.35–0.465 nm² decreased the rate of reaction. Received: 3 November 1999/In revised form: 21 January 1999/Accepted: 27 January 1999