EPEG型聚羧酸减水剂的合成及性能研究

Study on dispersion properties of EPEG polycarboxylate superplasticizer

乙二醇单乙烯基聚乙二醇醚(EPEG)是新型的聚羧酸减水剂用合成大单体,通过正交试验研究酸醚比、反应温度、引发体系和反应滴加时间对EPEG型聚羧酸减水剂分散性的影响,并采用红外光谱和核磁氢谱对合成减水剂进行表征。结果表明:4个因素对EPEG型聚羧酸减水剂分散性能影响程度排序为:滴加时间>反应温度>引发体系>酸醚比;最佳合成工艺为:酸醚比5.0,反应温度30℃,引发体系为Vc-双氧水,A料滴加时间30 min,B料滴加时间45 min。水泥净浆和混凝土性能测试表明,合成的聚羧酸减水剂兼具优良的减水性能和保坍性能。

Ethylene glycol monovinyl polyethylene glycol ether(EPEG)is a new type of synthetic monomer for polycarboxylate superplasticizer.The effect of acid-ether ratio,reaction temperature,initiator system,and addition time on dispersion properties of the EPEG polycarboxylate superplasticizer was studied by orthogonal test and characterized by infrared spectroscopy and hydrogen nuclear magnetic spectroscopy.The results show that the influence degree of the four kinds of reaction conditions on dispersing performance of the EPEG polycarboxylate superplasticizer(from big to small)is:addition time>reaction temperature>initiator system>acid-ether ratio.The optimum synthesis process as follows:acid-ether ratio 5.0,reaction temperature 30℃,initiation system Vc-hydrogen peroxide,addition time 30 minfor material A,and 45 min for material B.The test on dispersion performance of cement paste and concrete properties showed that the prepared EPEG polycarboxylate superplasticizer has excellent water-reducing performance and slump loss resistant property.