疏水烷基酯侧链对聚羧酸系减水剂分散及保坍性能的影响  

Effect of hydrophobic alkyl ester side chain on the dispersion and slump retention properties of polycarboxylate superplasticizer

作　　者：高瑞军[1] 王玲[1] 高春勇[1] 张萍[1] 

机构地区：[1]中国建筑材料科学研究总院绿色建筑材料国家重点实验室,北京100024

出　　处：《功能材料》2014年第13期13148-13152,共5页Journal of Functional Materials

基　　金：国家"十二五"科技支撑资助项目(2011BAE27B03);中国建筑材料科学研究总院青年科学基金资助项目(YA-485)

摘　　要：为了研究聚羧酸系减水剂(PCA)分子结构中疏水侧链对新拌混凝土坍落度及其损失的影响,以马来酸酐(MA)、异戊烯醇聚氧乙烯醚(TPEG)和丙烯酸烷基酯为原料,过硫酸铵为引发剂,通过自由基聚合合成了4种不同疏水侧链长度(疏水侧链含碳个数分别为4、8、12和18)的聚羧酸系减水剂。通过水泥净浆流动度、流动性损失等指标检验了聚羧酸系减水剂的分散性能及保坍性能,结果表明随着疏水侧链长度的增加,聚羧酸系减水剂的分散性能逐渐提高,保坍性能有所改善。吸附量和zeta电位测试结果解释了这种现象的原因,随着疏水侧链长度的增加,水泥颗粒表面zeta电位绝对值逐渐增加,水泥颗粒表面上的持续吸附能力逐渐增强。In order to study how the hydrophobic side chain in polycarboxylate superplasticizer structure affect the slump loss of the fresh concrete,four polycarboxylate superplasticizer （PCA）with different hydrophobic side chain length were synthesized by free radical copolymerization of maleic anhydride （MAH）,methallyl alco-hol polyethylene oxide ether （TPEG）and acrylic alkyl ester using ammonium persulfate [（NH4 ）2 SO4 ,APS]as initiator.The dispersing and flow retention performance of the four PCA was investigated respectively by tes-ting the fluidity of cement paste.The adsorption mechanism of NPC was discussed by testing the adsorption amount and zeta potential.The fluidities and flow loss of cement paste show that the dispersing performance of PCA gradually improves with the increase of the hydrophobic side chain length.The results of the zeta potential and the continuous adsorption ability of PCA on the surface of cement particles gradually increase with increas-ing the length of the hydrophobic side chain.

关 键 词：聚羧酸系减水剂 疏水侧链 分散性能 吸附 

分 类 号：TU528[建筑科学—建筑技术科学]