摘要
针对疏水性粉末常难以均匀分散在水泥砂浆中的问题,制备了一种硬脂酸基疏水剂,以提高水泥砂浆的整体疏水性。通过改进工艺,掺加4%复合乳化剂[m(Span60):m(MOA-3PK-40)=1:2],乳化时间2 h,制备得到固含量28%、黏度较小和分散性良好的乳液状硬脂酸基疏水剂。研究了硬脂酸基疏水剂掺量对水泥砂浆性能的影响。结果表明,掺加适量硬脂酸基疏水剂后改性砂浆内外表面水接触角明显增大,掺量为4%时外表面水接触角为134°,48 h吸水量比降至25.9%,砂浆整体疏水效果好,抗氯离子渗透性能明显提高。结合砂浆断面的微观结构分析可知,当硬脂酸基疏水剂掺量过多时,砂浆内部孔隙变多,强度有所降低。
A stearic acid based hydrophobic agent was prepared to improve the overall hydrophobicity of cement mortar,in response to the problem that hydrophobic powders are often difficult to uniformly disperse in cement mortar.Firstly,by improving the process,adding 4%compound emulsifier with mass ratio[m(Span60):m(MOA-3PK-40)=1:2]and emulsifying for 2 h,the lotion like stearic acid based hydrophobic agent with solid content of 28%,low viscosity and good dispersion was prepared.The effect of the dosage of stearic acid based hydrophobic agent on the properties of cement mortar was studied.The results showed that the addition of an appropriate amount of stearic acid based hydrophobic agent significantly increased the water contact angle on the inner and outer surfaces of the modified mortar.When the dosage was 4%,the water contact angle on the outer surface was 134°,and the 48 hour water absorption ratio decreased to 25.9%.The overall hydrophobic effect of the mortar was good,and the resistance to chloride ion penetration was significantly improved.Based on the microstructure of the mortar section,it can be concluded that when the dosage of stearic acid based hydrophobic agent is too high,the internal pores of the mortar increase and the strength decreases.
作者
安雪晖
张超
白皓
姚国友
AN Xuehui;ZHANG Chao;BAI Hao;YAO Guoyou(Tsinghua University,Beijing 100084,China;JiaGushi New Materials Co.Ltd.,Suzhou 215100,China)
出处
《新型建筑材料》
2025年第8期101-105,共5页
New Building Materials
基金
国家重点研发计划项目(2022YFC3801600)。
关键词
硬脂酸基疏水剂
乳液
疏水
整体改性
stearic acid-based hydrophobic agent
emulsion
hydrophobic
bulk modification
