MQ硅树脂复合硅烷偶联剂制备建筑防水剂的性能研究

Study on Properties of Building Waterproofing AgentsPrepared by MQ Silicone Resin and Silane Coupling Agent

采用水玻璃法制得数均摩尔质量为2.12×10~3 g/mol、摩尔质量分布系数为1.65的MQ硅树脂,将该MQ硅树脂分别添加至异丁基三乙氧基硅烷(IBTES)和辛基三乙氧基硅烷(OTES)中,制得复合有机硅防水剂IBTES-MQ和OTES-MQ。探讨了复合有机硅防水剂对砂浆块试件吸水率和渗透性的影响。结果表明,IBTES-MQ和OTES-MQ的防水性能良好。当MQ硅树脂质量分数从5%增至25%时,经IBTES-MQ处理的砂浆块试件吸水率从1.12%降至0.49%,经OTES-MQ处理的砂浆块试件吸水率从4.49%降至0.34%。在MQ硅树脂质量分数为15%的条件下,延长浸水前的放置时间至7 d,经IBTES-MQ和OTES-MQ处理的砂浆块试件浸水24 h后的吸水率分别为0.60%和0.51%,当浸水时间从24 h延长至120 h时,吸水率缓慢升至1.06%和0.89%,且在相同浸水时间和MQ硅树脂质量分数条件下,经OTES-MQ处理的砂浆块试件吸水率均低于IBTES-MQ处理的砂浆块试件。经复合有机硅防水剂处理的砂浆块试件在标准条件和热、低温、紫外光、酸液和碱液处理条件下静置240 h时,玻璃管中液面无明显变化,且试件背面均无水迹,滤纸也无变色,抗水渗透性良好。

MQ silicone resin(number average molecular weight of 2.12×10~3,polydispersity coefficient of 1.65)has been prepared by water glass method.Then the MQ silicone resin has been added into isobutyltriethoxy silane(IBTES)and octyltriethoxy silane(OTES)respectively,to prepare composite silicone waterproofing agents IBTES-MQ and OTES-MQ.The influence of composite silicone waterproofing agent on water absorption and permeability of mortar block is discussed.The results show that IBTES-MQ and OTES-MQ have good waterproof properties.When the mass fraction of MQ silicone resin increases from 5%to 25%,the water absorption of mortar block treated by IBTES-MQ reduces from 1.12%to 0.49%,and the water absorption of mortar block treated by OTES-MQ reduces from 4.49%to 0.34%.The MQ silicone resin,which has the mass fraction of 15%,prolongs the storage time to 7 days before immersion,the water absorption of mortar blocks treated by IBTES-MQ and OTES-MQ after immersion for 24 hours is 0.60%and 0.51%respectively after immersion for 24 hours by prolonging the immersion time to 7 days.When the immersion time is extended from 24 hours to 120 hours,the water absorption increases slowly to 1.06%and 0.89%respectively.In addition,the water absorption of OTES-MQ treated mortar block is lower than that of IBTES-MQ treated mortar block under the same soaking time and MQ silicone resin mass fraction.When the mortar block treated with composite silicone water repellent agent is kept to stand for 240 hours under standard conditions,heat,low temperature,ultraviolet light,acid and alkali treatment conditions,there is no obvious change in the liquid level in the glass tube,no trace on the back of the mortar block,and no discoloration on the filter paper.This shows that it has good water permeability resistance.