【摘要】 以乙二醇单乙烯基聚氧乙烯醚(EPEG)与丙烯酸(AA)为单体，通过自由基共聚反应合成聚羧酸高效减水剂(PCE)。通过单因素实验考察酸醚比、氧化剂用量、链转移剂用量、滴加时间对水泥净浆流动度的影响，确定最佳合成参数:酸醚比为2.75、氧化剂质量分数为1.1%、链转移剂质量分数为0.65%、反应温度为30℃、滴加时间为30 min。在此条件下，PCE的水泥净浆流动度达340 mm，分散性能优异。凝胶渗透色谱测试可得:数均分子质量、重均分子质量分别为5 591 Da、6 639 Da，多分散性指数为1.19,PCE转化率为89.6%，流体动力学半径为9.83 mm，证实PCE具有高转化率、适中分子质量和良好的分散性。更多还原

【Abstract】 Polycarboxylate superplasticizer( PCE) was synthesized by free radical copolymerization of ethylene glycol monovinyl polyoxyethylene ether( EPEG) and acrylic acid( AA). The effects of acid ether ratio,oxidant dosage,chain transfer agent dosage and dropping time on the fluidity of cement paste were investigated by single factor experiment,and the optimal synthesis parameters were determined as follows∶ acid ether mass ratio was 2. 75,oxidant mass fraction was1. 1%,chain transfer agent mass fraction was 0. 65%,reaction temperature was 30 ℃,and dropping time was 30 min.Under these conditions,the fluidity of PCE cement paste is 340 mm,and the dispersion performance is excellent. GPC test showed that the number average molecular weight and weight average molecular weight were 5 591 Da and 6 639 Da,respectively,the polydispersity index was 1. 19,the PCE conversion was 89. 6%,and the hydrodynamic radius was9. 83 mm,which confirmed that PCE had high conversion,moderate molecular weight and good dispersion.更多还原