- 目录
- 化学建材
- 首页
不同聚羧酸减水剂分子结构作用机制研究
作者：文帅涛，柯凯
（湖北工业大学 材料与化学工程学院，湖北 武汉 430068）
摘要：采用2-甲基丙-2-烯基聚乙二醇醚和丙烯酸进行自由基共聚，以酸醚比分别为2.8、3.7、4.6，并调整链转移剂TGA用量，合成了适当主链长度和不同侧链密度的聚羧酸减水剂。通过GPC、净浆流动度、吸附量、Zeta电位等测试，研究主链长度相近、侧链密度不同的聚羧酸减水剂在不同C3A含量水泥浆体中的吸附-分散特性。试验结果表明：侧链密度高，主链长度相应缩短，可以形成初始吸附量相近的减水剂分子构象；对于掺C3A的水泥，侧链密度较高的减水剂分散性能较优，且水泥中C3A含量越高，高侧链密度减水剂的抗吸附性能优势更明显。
关键词：聚羧酸减水剂；合成；主链长度；侧链密度；分散性
中图分类号：TU528.042+.2 文献标识码：A 文章编号：1001-702X（2020）02-0022-05
Study on molecular structure and action mechanism of different polycarboxylate superplasticizer
WEN Shuaitao，KE Kai
（School of Materials and Chemical Engineering，Hubei University of Technology，Wuhan 430068，China）
Abstract：This study examines the mechanism of adsorption-dispersion by superplasticizers with varying side chain density in cement paste. Acrylic acid was used to copolymerize with 2-methylprop-2-ene polyethylene glycol，using chain transfer agent to synthesize polycarboxylate ether superplasticizers（PCE） with comparable main chain lengths and different side chain densities.
GPC，fluidity tests，TOC and Zeta potential were used to investigate the adsorption-dispersion of PCE samples in cement pastes with different amounts of C3A additive. The results indicate：products with higher side chain densities also have correspondingly shorter main chains，which allows them to form conformations with comparable initial adsorption performance，with C3A added，samples with denser side chains performed better，and their resistance to adsorption became more prominent at higher C3A content.
Key words：polycarboxylate superplasticizer，synthesis，main chain length，side chain density，dispersity