降黏型聚羧酸减水剂的合成与性能研究

采用不饱和聚醚大单体与丙烯酸、引发剂等在水溶液体系中进行自由基共聚,同时在分子主链引入含憎水基团的醋酸乙烯酯、甲基丙烯酰氧乙基马来酸单酯,合成了降黏型聚羧酸减水剂PC-1。红外光谱和凝胶渗透色谱分析表明,PC-1具有预期的化学结构;采用涂-4黏度杯和旋转黏度计测试水泥净浆的黏度,结果表明,PC-1具有优异的降黏效果,同时兼具较好的初始分散性和保坍性。C50混凝土应用试验表明,掺PC-1的初始和2 h混凝土倒坍筒排空时间均明显优于国内同类产品PC-2,与国外同类产品PC-3相当。

Study on the synthesis and properties of viscosity-reducing type polycarboxylate superplasticizer

The viscosity-reducing type polycarboxylate superplasticizer PC-1 are prepared by free radical copolymerization of an unsaturated polyether macromonomer with acrylic acid and initiator in an aqueous solution system,and introduction of a vinyl halide-containing vinyl acetate, methacryloyloxyethyl maleic acid monoester in the molecular main chain. The synthetic polymers are characterized by IR and GPC. It shows that the sample of the PC-1 has the expected chemical structure. The viscosity of the paste were tested by coating-4 viscosity cups and rotary viscometer. The results showed that PC-1 had excellent viscosity-reducing effect and good initial-dispersion and slump retention. The results of C50 concrete test show that collapsed down of slump cone vibration empty time of PC-1 in initial and 2h are obviously better than those of the same kind PC-2 at home,and it is equivalent to the aboard products of the same kind PC-3.