选用聚醚和羟基酯通过自由基聚合成了缓释型聚羧酸分散剂，通过核磁共振氢谱对结构进行了表征，并运用zeta电位和吸附动力学对其作用机理进行了探索，研究表明，羟基酯在水泥的碱性环境下能够释放出吸附基团，进而补充被水化产物覆盖的分散剂发挥分散作用，且随着时间的延长，可吸附的分散剂持续增加，使其对水泥颗粒的分散性在一定时间范围内逐渐增强。另外，随着羟基酯比例的增加，释放的吸附基团增加，分散作用增加。
Slow-released polycarboxylate dispersants were synthesized with polyether and hydroxy esters by free radical polymerization.The structure of products were identified by 1 H NMR spectra,and the mechanism of dispersion was explored by zeta potential and adsorption kinetics.The results showed that hydroxyl esters could release adsorptive group in alkaline environment of cement,to play a role of dispersion as supplementary disper-sant covered by hydration products.The adsorption of dispersants continued to increase with the time,the dis-persion of cement particles in a certain time gradually enhanced.In addition,with the increase of hydroxy esters ratio,the release of adsorptive groups increased,the dispersion effect increased.
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