Effects of comb-like PCE and linear copolymers on workability and early hydration of a calcium sulfoaluminate belite cement
Effects of comb-like PCE and linear copolymers on workability and early hydration of a calcium sulfoaluminate belite cement
复制标题
梳状四氯乙烯和线性共聚物对硫铝酸钙贝利特水泥和易性及早期水化的影响
DOI：
10.1016/j.cemconres.2019.105801
复制
发表时间：
2019-09-01
影响因子：
11.4
通讯作者：
Wang, Dongmin
中科院分区：
文献类型：
--
作者：
Su, Tong;Kong, Xiangming;Wang, Dongmin
硫铝酸钙水泥水化速度快，流动性控制和凝结调整是其实际应用中的两个关键问题。合成了一种常用的梳状聚羧酸减水剂（PCE）和丙烯酸（AA）与2-丙烯酰胺基-2-甲基丙磺酸（AMPS）的线性共聚物（PAS），研究了它们对硫铝酸钙贝利特水泥（CSAB）流动性和早期水化的影响。结果表明，线性PAS聚合物在分散新拌水泥浆体（fcps）中是非常有效的，并有效地抑制水泥的早期水化。PAS分子中AA单元越多，对水泥水化的抑制作用越强。与PAS聚合物相比，PCE对水泥水化几乎没有抑制作用，尽管PCE具有较高的初始水化速率。因此，与含有fcp的PCE相比，含有PAS聚合物的水泥浆表现出优异的流动性保持性，这是由于PAS聚合物对AFt晶体的早期形成的强烈延迟作用。
Fluidity control and setting adjustment are two critical issues for practical applications of calcium sulfoaluminate cement because of rapid hydration. A commonly used comb-like polycarboxylate superplasticizer (PCE) and linear copolymers (PAS) of acrylic acid (AA) and 2-acrylamido-2-methylpropane sulfonic acid (AMPS) with varied monomer ratio were synthesized to study their impacts on fluidity and early hydration of calcium sulfoaluminate belite cement (CSAB). Results show that the linear PAS polymers are very effective in dispersing fresh cement pastes (fcps) and effectively inhibit early hydration of the cement. More AA unit in the PAS molecules leads to stronger inhibition effect on cement hydration. Compared with the PAS polymers, PCE exhibits almost no inhibition effect on cement hydration despite the high initial dispersibility. Thus, cement pastes containing PAS polymers exhibits excellent fluidity retention compared with the PCE containing fcp due to strong retardation effect of the PAS polymers on early formation of AFt crystals.