新型聚羧酸引气型外加剂的常温合成及其性能研究

Synthesis of Novel Polycarboxylic Acid-based Air-entraining Additive for Concrete at Normal Temperature and its Performance Study

以不饱和两亲性脂肪醇聚氧乙烯醚(uAEO-x,x=3,30,80)、甲基丙烯酸、甲基烯丙基聚氧乙烯醚为原料,常温下合成了系列具有两亲性结构侧链的新型聚羧酸类引气剂pAEO-x。该文研究了AEO中亲水性链段长度对起泡容量、气泡稳定性及其对混凝土强度的影响。结果表明:pAEO-x中醚链段的重复单元x=30时,其水溶液在24h后仍有25.7%的泡沫残余,气泡容量和稳定性明显好于x=3和80;pAEO-x在混凝土拌合物中的应用显示,随AEO中醚段x=3增至30,80,混凝土拌合物60min经时坍落度先增加后减少,28d强度降低约3%。

Series of polycarboxylic acid-based air-entrainment agents （pAEO- x ） containing amphipathic fatty alcohol-polyoxyethylene ether were obtained at normal temperature via the copolymerization of unsaturated fatty alcohol-polyoxyethylene ether （uAEO- x,x =3,30,80）,methacrylic acid and methyl allyl-polyoxyethylene ether.Influence of the polyoxyethylene ether units x in AEO on the foam ability,stability and strength of the concrete were investigated.Results show that when repeating unit of ether segment in pAEO- x x is equal to 30,the surfactant pAEO-30 has higher foaming performance compared with its analogues of pAEO-3/-80 respectively,and 25.7% of residual foam would be existed even after 24 h.With segment of the polyoxyethylene ether from 3 to 30,80,time-loss of slump constant for concrete mixture 60 min first increase and then decrease,while the compressive strengths of the 28 d harden concretes show 3% decrease.