用于水泥沥青砂浆的聚羧酸减水剂的制备

Preparation of polycarboxylic acid superplasticizer used into CA mortars

采用聚乙二醇单甲醚(1000、2000)、甲基丙烯酸、阻聚剂、催化剂、引发剂、苯乙烯、丙烯酰胺和对苯乙烯磺酸钠合成了用于水泥沥青砂浆的聚羧酸减水剂。研究了酸醇摩尔比和苯乙烯、丙烯酰胺、对苯乙烯磺酸钠的用量对合成减水剂性能的影响。对聚羧酸减水剂配比进行了优化,进行了中试,制备了CA砂浆样板,并进行性能测试。用GPC对中试聚羧酸减水剂进行了表征。结果表明:大单体的制备及减水剂聚合工艺是可行的。最佳酸醇摩尔比为4.0∶1.0,苯乙烯和丙烯酰胺的最佳用量均为3%,对苯乙烯磺酸钠用量以不超过3%为宜。掺该合成聚羧酸减水剂的CA砂浆性能良好,制备的CA砂浆样板基本无缺陷。

Polycarboxylic acid superplasticizer used into CA mortars was synthesized with methoxypolyethylene glycol 1000, methoxypolyethylene glycol 2000, methacrylic acid, inhibitor, catalyst, initiator, styrene,acrylamide, and sodium p-styrene sulfonate. Ef- fects of molar ratio of acid,content of styrene, acrylamide, and sodium p-styrene sulfonate on the performance of CA mortar were researched. The ratio of polycarboxylic acid superplasticizer was optimized. The optimized ratio of polycarboxylic acid was piloted, and made a CA model. Pilot Polycarboxylate product was characterized by GPC. The results showed that the process of big monomer prepared and polycarboxylic acid superplasticizer synthesized were feasible. The optimal molar ratio of acid was 4.0：1.0, optimal content of styrene and acrylamide were both 3%, and the content of sodium p-styrene sulfonate should not be more than 3%. CA mortar had good performance and the model had no defects when polycarboxylic acid superplasticizer was added into the CA mortar.