聚羧酸系减水剂对水泥分散和水化产物的影响  

Effect of Polycarboxylate-Type Water-Reducer on Dispersion and Hydration Products of Cement

作　　者：彭雄义[1,2] 易聪华[1,2] 张智[1,2] 欧阳新平[1,2] 邱学青[1,2] 

机构地区：[1]华南理工大学化学与化工学院,广东广州510640 [2]华南理工大学制浆造纸工程国家重点实验室,广东广州510640

出　　处：《建筑材料学报》2010年第5期578-583,共6页Journal of Building Materials

基　　金：广东省科技计划项目(2008B010600014);广东省自然科学基金资助项目(8351064101000002);国家自然科学基金资助项目(20925622)

摘　　要：合成了3种聚氧乙烯链长的聚羧酸系减水剂,表征了它们的相对分子质量,并研究了它们对水泥颗粒分散性能和水泥水化产物性质的影响.研究表明:长短支链交替组成的聚羧酸系减水剂对水泥颗粒具有较好的分散性能,聚羧酸系减水剂的分散机理主要是其支链产生的空间位阻作用;掺加聚羧酸系减水剂后,水泥浆体需水量减少,在水化28 d内,水泥熟料的水化速率减小,水化产物数量减少;水化产物的孔径范围变小,硬化水泥石密实程度提高.Three kinds of polycarboxylate-type water-reducers（PCs） with different length of poly（ethylene oxide） （PEO） branch were synthesized and the relative molecular mass of the PCs was characterized with gel permeation chromatography（GPC）. The effect of the PCs on the dispersion and hydration products of cement was investigated. The results show that the PCs composed of alternating long chain branch and short chain branch have a good dispersive effect on the cement particles, and the steric hindrance produced by branch of PCs plays a major role in the dispersing process of cement particles. When the PCs are added into cement paste, the water demand of the cement paste decreases, the hydration rate of cement clinker becomes low, the amount of hydration products decreases, the range of pore diameters of hydration products becomes narrow, and the density of hardened cement paste is increased during the 28 days hydration period.

关 键 词：聚羧酸系减水剂 水化产物 分散机理 

分 类 号：TQ172.11[化学工程—水泥工业]