两种引发体系下降黏型聚羧酸减水剂的合成及其应用

以二乙二醇二甲基丙烯酸酯、二乙二醇单丁醚、甲基丙烯酸甲酯(MMA)、异戊烯醇聚氧乙烯醚(TPEG)为主要原料,采用过硫酸铵(APS)、双氧水/抗坏血酸(H2O2/Vc)2种引发体系,合成系列降黏型聚羧酸减水剂。试验结果表明:与市售同类产品相比,在APS引发体系下合成的PCA-2、PCA-3和在H2O2/Vc引发体系下合成的PCA-7降黏型聚羧酸减水剂对C50自密实混凝土的降黏效果更优;APS引发体系较适用于合成甲基丙烯酸甲酯、二乙二醇单丁醚类减水剂,H2O2/Vc引发体系较适用于合成二乙二醇二甲基丙烯酸酯类减水剂。

Synthesis and application of two kinds of initiating system drop viscosity polycarboxylate water reducer

In this paper,diethylene glycol dimethacrylate,diethylene glycol monobutyl ether,methyl methacrylate(MMA),prenyl alcohol polyoxyethylene ether(TPEG)as the main reaction raw materials,using ammonium persulfate(APS),hydrogen peroxide/sodium ascorbate(H2O2/Vc)two initiation systems,a series of excellent viscosity-reducing polycarboxylic acid water reducer was prepared.The test results show that thereduced viscosity polycarboxylate superplasticizer PCA-2,PCA-3 synthesizedunder the APS initiation system and PCA-7 synthesized under H2O2/Vc initiation system have better viscosity reduction effect on C50 self-compacting concrete than that of similar products on the market.The APS initiation system is more suitable for the synthesis of methyl methacrylate and diethylene glycol monobutyl ether water reducer,while the H2O2/Vc initiation system is more suitable for the synthesis of diethylene glycol dimethacrylate water reducer.