Abstract: With tetraethyoxysilane(TEOS) as silicon source,hydrochloric acid as acidic catalyst,and ethanolamines(monoethanolamine,diethanolamine,and triethanolamine)and ammonia as alkalescence catalysts,wet silica aerogel was prepared by acid/base two-step catalytic process sol-gel method.Silica aerogel was then prepared by vacuum drying without surface modification.Physical properties and structures of the prepared samples were characterized by BET and SEM etc..Results showed different ethanolamines can make different properties of silica aerogel.Comparing with ammonia,silica aerogel had larger average aperture if ethanolamines as catalyst;comparing with ammonia,adsorbing ability and porosity of silica aerogel was increased,harshness of internel surface was decreased,and the wall collapse of hole was lightened if monoethanolamine as catalyst and the dosage was (5.1～8.5)×10^-2mol;comparing with other basic catalysts,diethanolamine can make bigger increase on the mean pore size of silica aerogel;comparing with other basic catalysts,triethanolamine made the roughest internal surface.

Key words: silica aerogel, ethanolamines, alkalescence catalyst