The esterified silica gel was prepared by the reaction between the surface hydroxyl groups of silica gel and n-heptanol or n-octanol. The phys. structure, water vapor adsorption isotherms, heat of wetting, DTA and IR for esterified silica gel were determine The results indicate: (1) for all esterified silica gels dT, S and V are all decreased, and dA is increased, but 2r suffers only a small change; (2) the esterified silica gel is hydrophobic, it shows a remarkable decrease in water vapor adsorption, and in heat of wetting for water and cyclohexane; (3) the surface ester groups of esterified silica gel are destroyed at 235-350 癈 in air; (4) the esterification reaction is reversible and the surface ester groups of silica gels were hydrolyzed in water by about 41-47%.

Key words: INFRARED SPECTROPHOTOMETRY, ESTERIFICATION, ALCOHOL, SURFACE PROPERTY, SILICA GEL, DIFFERENTIAL THERMAL ANALYSIS, STRUCTURE, HYDROXYL COMPOUNDS