丙烯酸乳液改性抹面砂浆及其性能探究  

Study on acrylic emulsion modified plaster mortar and its properties

作　　者：裴须强 朱玉雪 李婷 力乙鹏 PEI Xuqiang;ZHU Yuxue;LI Ting;LI Yipeng(China Building Materials Academy,Beijing 100024,China;CNBM Zhongyan Technology Co.,Ltd.,Beijing 100024,China;National Building Materials Engineering Technology Center for Protective Repair and Reinforcement,Beijing 100024,China)

机构地区：[1]中国建筑材料科学研究总院有限公司,北京100024 [2]中建材中岩科技有限公司,北京100024 [3]全国建筑材料行业防护修复与加固材料工程技术中心,北京100024

出　　处：《混凝土》2023年第7期131-135,共5页Concrete

基　　金：国家重点研发计划“钙质矿物掺合料制备高抗裂预拌混凝土关键技术”(2017YFB0310104-03)。

摘　　要：结合现场施工对抹面砂浆湿黏结强度≥2.5 MPa或黏结界面为内聚破坏的技术指标要求,以已有的粉料体系为基础,引入丙烯酸乳液对抹面砂浆进行改性,并探究了丙烯酸乳液的掺量对砂浆工作性能、力学性能以及黏结性能的影响,结果显示:随着丙烯酸乳液掺量的增加,抹面砂浆的凝结时间和可操作时间延长,力学性能变差,黏结性能得到提升。综合考虑,优选出乳液掺量为9%的抹面砂浆,其终凝时间为860 min,可操作时间达30 min;28 d抗压强度41.36 MPa,抗折强度10.75 MPa;28 d干黏结强度1.65 MPa,湿黏结强度2.69 MPa;同时,对部分抹面砂浆进行了扫描电镜测试分析,进一步证实了乳液对水泥颗粒的包裹现象。最后,利用智能黏结强度测试仪与市面上优选的抹面砂浆进行了砖墙拉拔强度对比,结果显示自制抹面砂浆28 d拉拔强度达1.80 MPa,且黏结界面为内聚破坏。In combination with the technical index requirements of on-site construction for wet bonding strength of plastering mortar≥2.5 MPa or cohesive failure of bonding interface,this study is based on the existing powder system,introducing acrylic emulsion to modify the plaster mortar,and exploring the influence of the amount of acrylic emulsion on its performance,mechanical properties and bonding properties.The results showed that with the increase of the dosage of acrylic emulsion,the operation time and setting time of the mortar were prolonged,the mechanical properties became worse,and the bonding properties were improved.Taking into account,the mortar with 9%emulsion content is selected,the final setting time is 860 min,the operation time is 30 min.The 28 d compressive strength is 41.36 MPa,the flexural strength is 10.75 MPa.The 28 d dry bonding strength is 1.65 MPa,wet bonding strength is 2.69 MPa;at the same time,some coating mortar was tested and analyzed by SEM,and the inclusion phenomenon of cement particles was further confirmed.Finally,the pull-out strength of brick wall is compared with the best plastering mortar in the market by using the intelligent bonding strength tester,the results show that the pull-out strength of self-made plastering mortar in 28 days is 1.80 MPa,and the bonding interface is cohesive failure.

关 键 词：丙烯酸乳液 改性 抹面砂浆 黏结性能 内聚破坏 

分 类 号：TU528.01[建筑科学—建筑技术科学]