新型梳形聚羧酸系减水剂大分子的制备与性能研究

以甲基丙烯酸、丙烯酸和聚乙二醇为主要原料,以甲苯为带水剂,混酸为催化剂,对苯二酚为阻聚剂,通过酯化反应合成出甲基丙烯酸聚乙二醇单酯活性大单体,最佳反应条件为:原料醇酸物质的量比为1∶2,催化剂的用量为4%(以聚乙二醇的质量计),阻聚剂对苯二酚的用量为0.3%(以甲基丙烯酸的质量计),温度为95℃,反应时间为8 h,酯化率达86.4%。

Preparation and performance study on new macromolecule for polycarboxylate superplasticizer

Methacrylate polyglycol monoester was synthesized by condensation of polyethylene glycol and methacrylic acid with toluene as the water absorbent.Mixed acid as the catalyst and hydroquinone as the inhibitor.The optimum reaction conditions:the molar rate of PEG to acrylic acid was 1 ∶ 2,the reaction temperature was 95 ℃,the reaction time is 8 h,the amount of catalyst is 4%,according to the mass of PEG,the amount of inhibitor is 0.3% according to the mass of MAA,the rate of esterification to 86.4%.