柠檬酸改性聚羧酸减水剂的合成  

The synthesis of polycarboxylate superplasticizer modified by citric acid

作　　者：王文平[1] 吕晓勇[1] 丁伟良[1] 唐家元[1] 汪慧[1] 

机构地区：[1]合肥工业大学化学工程学院,安徽合肥230009

出　　处：《新型建筑材料》2012年第7期9-12,共4页New Building Materials

摘　　要：以2-丙烯酰氧基-1,2,3-三羧基丙烷(ACP)、丙烯酸(AA)、丙烯酸聚乙二醇单甲醚酯(MPA)和甲基丙烯磺酸钠(MAS)为单体,过硫酸铵(APS)为引发剂,采用水溶液共聚法合成柠檬酸改性四元聚羧酸系减水剂。实验结果表明,改性聚羧酸减水剂的最优合成条件为:反应温度90℃,反应时间5 h,APS用量为单体总质量的2.5%,在单体配比为n(ACP)∶n(AA)∶n(MPA)∶n(MAS)=0.47∶3.5∶1.2∶1.0,所合成减水剂的减水率高达31%,2 h内水泥净浆流动度基本无损失。A novel polycarboxylate superplasticizer modified by 2-hydroxy-l,2,3-propanetricarboxylic acid was prepared. The superplasticizer was directly polymerized using 2-acryloyloxy-1,2,3-tricarboxylic propane （ACP）,acrylic acid（AA）,methoxypolyethy- lene glycol acrylate （MPA）, and sodium methylallyl sulfonate （MAS） with ammonium persulfate as initiator in aqueous media. The re- sults showed that the optimum reaction condition are as follows：the molar ratio of ACP to AA to MPA to MAS is 0.47：3.5：1.2：1.0, the dosage of ammonium persulfate is 2.5% of total monomers by mass, the reaction temperature is 90℃ and the reaction time is 5 h. The polycarboxylate superplasticizer prepared under this condition would have good plasticizing and fluidity. The water-reduc- ing ratio for SPC is 31%,the fluidity of cement paste＇ almost remained constant in 2 h.

关 键 词：聚羧酸减水剂 柠檬酸 改性 净浆流动度 

分 类 号：TU528.042.2[建筑科学—建筑技术科学]