乳液聚合法制备降黏型聚羧酸减水剂

Research of Viscosity Reducing Polycarboxylate Superplasticizer Synthesized by Emulsion Polymerization

为了解决高强度等级混凝土在拌制过程中存在的黏度高、流速慢问题,以甲基烯丙基聚氧乙烯醚、甲基丙烯酸丁酯、丙烯酸、甲基丙烯酸为主要原材料,通过自由基聚合方法合成一种降黏型聚羧酸减水剂,研究了酸醚比、酯醚比、乳化剂用量等试验因素对减水剂性能影响。试验结果表明:减水剂最佳合成工艺为酸醚比为3.5,酯醚比为1.5,AA∶MAA用量比例为2,反应温度为35~45℃,乳化剂用量为体系质量的0.4%,混凝土试验结果显示该产品具备良好降黏性能,能够有效降低混凝土塑性黏度。

In order to solve the problems of high viscosity and slow flow rate in the mixing process of high-strength concrete, viscosity reducing polycarboxylic superplasticizer was synthesized by free radical polymerization with Methylallyl polyoxyethylene ether, butyl methacrylate, acrylic acid and methacrylic acid. The acid ether ratio, ester ether ratio, the amount of emulsifier and other test factors were investigated. The test results show that the optimum synthesis process of polycarboxylic superplasticizer is that the acid ether ratio is 3.5, the ester ether ratio is 1.5, the dosage ratio of AA ∶MAA is 2, the reaction temperature is 35-45 ℃, and the dosage of emulsifier is 0.4% of the system quality. The product shows good viscosity reduction performance in the concrete test, and effectively reduce the plastic viscosity of concrete.