羧酸型减水剂与水泥的相容性研究

Study on compatibility of polycarboxylate-type superplasticizers with cements

选用含有亲水性羧基、酸酐基、磺酸基、聚环氧乙烷侧链的单体共聚合成了3种羧酸型减水剂,针对4种不同产地的P.O 42.5水泥,测定了在较低水灰比(mw/mc=0.29)下水泥净浆流动度及30 min经时变化,混凝土坍落度及180 min经时变化.净浆流动度30 min损失小于13.8%,混凝土坍落度60 min损失小于15%.3种羧酸型减水剂与不同水泥均具有良好的相容性.

Three polycarboxylate- type suPerplasticizers synthesized from different monomers with hydrophilic group such as carboxyl, sulfonate, anhydride and polyethylene oxide branched chain, four types of P. O 42. 5 cements from different producing areas, were used to determine the compatibility of cements with superplasticizers. At the lower water cement ratio （mw/mc= 0. 29）, the fluidity of different cement paste with different polycarboxylate - type superplasticizers and its timing - loss of 30 min were tested, the slump and the slump -loss of 180 min of different fresh cement concrete with different polycarboxylate - type superplasticizers were also determined. The timing - loss of the fluidity of different cement paste of 30 min is less than 13.8 percent, the slump -loss of 60 min of different fresh cement concrete is less than 15 percent. The compatibility of polycarboxylate -type Superplasticizers with different cements is better, the reasons were discussed.