沉淀法制备的固体聚羧酸减水剂性能研究

采用沉淀法制备了固体聚羧酸减水剂,依据国标方法对该聚羧酸减水剂的宏观性能进行测试,采用IR、GPC分析技术对其结构进行表征,并将其性能与传统方法制备的液体聚羧酸减水剂和外购固体聚羧酸减水剂进行比较研究.结果表明:采用沉淀法制备的固体聚羧酸减水剂减水率可达28%,初始坍落度为160 mm,经时坍损小;固化过程对聚羧酸减水剂官能团、分子量及多分散系数、水泥的吸附性均无明显影响;宏观性能方面虽然对水泥的分散作用、坍落度、硬化水泥砂浆抗压强度虽略低于液体聚羧酸减水剂,但各项指标均能达到国标要求,说明沉淀法制备固体聚羧酸减水剂是一条可行的途径.

Properties of Solid Polycarboxylate Superplasticizer Prepared by Precipitation Method

Preparation of solid polycarboxylate superplasticizer by precipitation method.The macroscopic performance was tested according to the national standard method and the structure was characterized by IR、 GPC analysis technology. Comparing its properties with liquid polycarboxylate superplasticizer prepared by traditional method and commercial solid polycarboxylate superplasticizer.The results show that the water reducing rate of solid polycarboxylate superplasticizer prepared by precipitation method is 28%, and small slump loss with the initial slump of 160 mm, the curing process for polycarboxylate superplasticizer had no negative effect on the functional groups, molecular weight and polydispersity, as well as on the absorbability on cement particles.All the parameters can meet the requirements of national standard, indicating that precipitation method is a feasible way to prepare solid polycarboxylate superplasticizer.