摘要
目的研究骨料中的泥对聚羧酸减水剂(PCE)分散作用的影响,并合成聚合物降低泥对聚羧酸减水剂的分散作用.方法以丙烯酰胺(AM)为单体,过硫酸铵(APS)为引发剂、甲基丙烯磺酸钠(SMAS)为链转移剂,合成一种低分子量的丙烯酰胺聚合物(PAM),并测试了不同含泥条件下水泥对聚羧酸减水剂的吸附量以及水泥的流动度,确定PAM的合理配比.结果自制的聚丙烯酰胺可明显改善泥对减水剂吸附,在细骨料含泥质量分数为5%、减水剂掺量为0.3%、水灰质量比为0.29条件下,PAM的最佳掺量为1.2%,泥对聚羧酸减水剂的影响可明显降低.结论泥与水泥相比对聚羧酸减水剂的吸附量较大,蒙脱石对于PCE的吸附导致减水剂失效;PAM与PCE之间存在吸附竞争,PAM可优先吸附,有利于水泥流动度的改善.
The effect of mud in aggregate and synthetic polymer on the dispersion of polycarboxylate superplasticizer(PCE)was studeied.Acrylamide(AM),Ammonium persulfate(APS)and sodium methacrylate sulfonate(SMAS)taken as monomer,initiator and chain transfer agent,a low molecular weight acrylamide polymer(PAM)was synthesized.The reasonable PAM ratio is determined by testing adsorption amount of the carboxylic acid water reducing agent and the fluidity of the cement under different mud conditions.As a result,the self-made polyacrylamide can obviously improve the adsorption of the mud to the water reducing agent.The optimum dosage of PAM is 1.2%when in the fine aggregate the mud is 5%,water reducing agent is 0.3%and water-mass ratio is 0.29,and the effect of mud on polycarboxylate superplasticizer can be significantly reduced.The adsorption amount of the mud to polycarboxylate water reducing agent is larger than that of cement.The adsorption of montmorillonite to PCE can cause the failure of the water reducing agent;there is adsorption competition between PAM and PCE,and PAM can preferentially adsorb,which is beneficial to the improvement of cement fluidity.
作者
丁向群
梁心语
沈洁
房延凤
DING Xiangqun;LIANG Xinyu;SHEN Jie;FANG Yanfeng(School of Materials Science and Engineering,Shenyang Jianzhu University,Shenyang,China,110168;Yingkou Magnesite Chemical IND Group Co.Ltd.,Yingkou,China,115100)
出处
《沈阳建筑大学学报（自然科学版）》
CAS
CSCD
北大核心
2020年第1期124-130,共7页
Journal of Shenyang Jianzhu University：Natural Science
基金
国家自然科学基金项目(51678374,51808354)
辽宁省自然科学基金项目(20180550092)
关键词
聚羧酸减水剂
聚丙烯酰胺
流动度
蒙脱石
polycarboxylate water reducing agent
polyacrylamide
fluidity
montmorillonite
作者简介
丁向群(1970-),男,教授,博士,主要从事水泥混凝土高性能化方面研究.
