聚羧酸减水剂在水泥、矿粉和粉煤灰表面吸附行为研究

Adsorption Behavior of Polycarboxylate Superplasticizer on Cement,Slag and Fly Ash Particulates

对比了掺聚羧酸减水剂的基准水泥、矿粉和粉煤灰三种粉料桨体初始流动度和经时流动度,通过吸附量、表面形貌和XPS测试分析作用机理。结果表明,基准水泥吸附量最大,吸附层最厚,因而初始流动度最高,矿粉次之,粉煤灰最小;与萘系减水剂相比,聚羧酸减水剂在低掺量时也有良好的保坍性。

Initial fluidity and fluidity loss of three pastes prepared with reference cement, slag and fly ash respectively incorporated with polycarboxylate superplastieizer were compared, then adsorptive amount, surface morphology and the XPS was used to analyse the action mechanism. The results show that the adsorptive amount polycarboxylate superplasticizer on reference cement is the largest, and the adsorption layer is the thickest, so that initial fluidity is the largest. While slag powder is second one and fly ash is the minimum. Compared with polynaphthalene sulphonate, paste also exhibits good slump retention when mixed with low polycarboxylate superplasticizer content.