摘要
通过实验对反应温度、反应时间、链转移剂、引发体系等因素对超高浓度聚羧酸系减水剂分散性能的影响进行了研究。结果表明,使用维生素C-双氧水氧化还原引发体系[n(H2O2)∶n(Vc)=4∶1],H2O2用量为大单体的1.5%,磷酸三钠用量为大单体的1.2%,SMAS用量为大单体的6%,在室温(20～40℃)条件下反应3 h,合成的超高浓度(质量浓度80%)聚羧酸系减水剂的分散性能优良。当减水剂折固掺量为0.20%、水灰比为0.29时,水泥净浆流动度可达285 mm,60 min净浆流动度为288 mm,120 min净浆流动度为282 mm,流动度经时损失小;同时其混凝土应用性能良好,减水率达30%。
Through experiments,the influence of reaction temperature and time,chain-transfer agent and initiator systems on the dispersivity performance of the extra high-concentration polycarboxylate superplasticizer was researched. The results indicated that the optimal reaction conditions were as follows： H2o2：Vc=4：1 （redox initiator system）, 1.5% dosage of hydrogen peroxide（mass of （mass of plasticizer ）, 1.2% dosage of sodium phosphate （mass of ）, at room temperature （20-40 ℃） for with extra high concentration （80%）. When 0.20% , used as a chain transfer agent）,6% dosage of SMAS 3 h,which can synthesize a high-performance polycarboxylate super- dosage（converted into solid）of superplasticizer and 0.29 of W/C,the net paste fluidity can reach up to 285 mm, 60 min net paste fluidity can be 288 mm, and 120 rain net paste fluidity can be 282 mm with little loss. Meanwhile its concrete application performance is good, and water-reducing rate reaches 30%.
出处
《新型建筑材料》
2013年第3期29-31,43,共4页
New Building Materials
关键词
超高浓度
聚羧酸减水剂
合成
性能
extra high-concentration
polycarboxylate superplasticizer
synthesis
performance
