Page 149 - 《精细化工》2019年第11期

第 36 卷第 11 期 精 细 化 工 Vol.36, No.11
2019 年 11 月 FINE CHEMICALS Nov. 2019

建筑用化学品
聚醚大单体溶液 pH 对减水剂性能的影响

张国宏，李晓利，张瑞琳，魏晓波，李虹阳

（沈阳工业大学 化工装备学院，辽宁 辽阳 111003）

摘要：以甲基烯丙醇聚氧乙烯醚和丙烯酸为主要原料，对聚醚单体溶液（底料）pH 进行调控合成聚羧酸减水剂。
通过测定聚醚转化率及减水剂相对分子质量及其分布以及评价减水剂的应用性能，确定了聚醚大单体溶液 pH
变化范围以及不同酸种类对减水剂性能的影响。结果显示，通过控制底料 pH 提高了聚醚大单体转化率，并且
当底料 pH 控制为 3 时其转化率最高，由未调控 pH 的 87.41%提升至 pH 为 3 时的 95.43%，此时合成减水剂的
分子量分布指数较小，由未调控 pH 时的 3.183 降至 2.884；采用硫酸控制底料 pH 时，溶液中存在的硫酸盐为硫
酸钠，其快速溶解减少了聚羧酸减水剂被水泥水化产物的包裹和消耗，更有利于提高聚羧酸减水剂分散性能。
结果表明，通过控制聚醚大单体溶液 pH 的方式，在不改变减水剂合成工艺操作的前提下也可提升聚羧酸系减
水剂的整体性能。
关键词：聚羧酸系减水剂；聚醚转化率；分子量分布指数；底料 pH 调控；建筑用化学品
中图分类号：TU528.042.2 文献标识码：A 文章编号：1003-5214 (2019) 11-2297-06

Effect of pH of Polyether Macromolecule Solution on
Properties of Water Reducer

ZHANG Guo-hong, LI Xiao-li, ZHANG Rui-lin, WEI Xiao-bo, LI Hong-yang
（School of Chemical Equipment, Shenyang University of Technology, Liaoyang 111003, Liaoning, China）

Abstract: A polycarboxylate-based water reducer was synthesized with methyl allyl alcohol
polyoxyethylene ether and acrylic acid as main raw materials by controlling pH of polyether monomer
solution (base material). The pH range of polyether macromonomer solution and the effect of different acid
types on the performances of water reducer were determined by measuring the conversion of polyether, the
water reducer's relative molecular weight and molecular weight distribution index, and evaluating the
application performances of water reducer. The results showed that the conversion rate of polyether
monomer was increased by controlling the pH of the base material. When the pH was controlled at 3, the
conversion rate of polyether was the highest, which increased from 87.41% of the blank to 95.43%.
Moreover, the molecular weight distribution index of synthetic water reducer was the lowest, decreasing
from 3.183 to 2.884. When sulfuric acid was used to control the pH of the base material, sodium sulfate was
present in the solution, its rapid dissolution reduced the encapsulation and consumption of polycarboxylate
superplasticizer by cement hydration products, which was more conducive to improving the dispersibility of
polycarboxylate superplasticizer. The results revealed that the overall performance of polycarboxylate
superplasticizer can be improved by controlling the pH of polyether macromonomer solution without
changing the synthetic process of water reducer.
Key words: polycarboxylate-based water reducer; conversion rate of polyether; molecular weight
distribution index; controlling the pH of base material; building chemicals

聚羧酸系减水剂是指能够在施工时较大幅度减 条件下依旧保持较好的流动性，可以明显改善混凝
少混凝土用水量，使所拌制的混凝土在较低水灰比 土的各种工作性能，延长混凝土建筑使用寿命的一

收稿日期：2019-04-09; 定用日期：2019-06-04; DOI: 10.13550/j.jxhg.20190294
作者简介：张国宏(1971—)，男，副教授，博士，E-mail：goodzgh@qq.com。