催化及杂化正硅酸乙酯防水剂的阻水性能

Water Resistance of Catalyzed and Hybridized TEOS Waterproof Agent

以正硅酸乙酯(TEOS)为无机前躯体,端羟基硅油(PDMS)为有机杂化剂,在两种催化剂酒石酸(TA)、二月桂酸二丁基锡(DBTL)的作用下,分别制备了TEOS水解-缩合溶胶、TEOS-PDMS杂化水解-缩合溶胶。利用制备的两种溶胶表层浸渍水泥净浆试件,通过测试处理水泥净浆试件的吸水率、接触角评价了两种防水剂的阻水效果;结合红外光谱分析了两种防水剂的形成过程以及作用机理。研究结果表明:表层浸渍处理的水泥净浆试件,其吸水率与水接触角具有良好的相关性;相比于TA,DBTL催化TEOS经水解-缩合形成的防水剂阻水性能更好;PDMS改性TEOS形成的TEOS-PDMS防水剂较杂化前具有更强的阻水性能;防水剂的阻水效果与其凝胶结构中的疏水基团数量密切相关。

TEOS hydrolysis-condensation sol and TEOS-PDMS hybrid hydrolysis-condensation sol were prepared respectively under the effect of tartaric acid （TA） and Dibutyltin dilaurate （DBTL） as the two kinds of catalysts when Tetraethyl orthosilicate （TEOS） was used as inorganic precursor and hydroxyl silicone oil （PDMS） was used as organic hybridization agent. Water resistance of TEOS hydrolysis- condensation sol and TEOS-PEMS hybrid hydrolysis-condensation sol as the waterproof agent was characterized by the absorption and contact angle of hardened cement past impregnated with the above waterproof agent, the formation process and action mechanism of two kinds of waterproof agent were analyzed by FTIR spectra. The results show that the water absorption and contact angle of cement specimen treated by surface protection agent has a good correlation, compared with TA, TEOS waterproof agent which is catalyzed by DBTL and formed from a way of hydrolysis-condensation has a better water resistance,TEOS-PDMS waterproof agent which is formed from PDMS modify TEOS has a better water resistance than TEOS waterproof agent, water resistance of waterproof agent is closely related to the number of hydrophobic group from gel structure.