从混凝土减水剂作用机理看高效减水剂的合成与复合方法

Discuss on the synthesizing and compounding methods of superplasticisers based on the action mechanisms of concrete plasticisers

本文在对减水剂的分子结构及其在水泥颗粒表面的吸附特性进行详细分析的基础上,将减水剂作用机理归纳为五个方面,即:降低水泥颗粒固液界面能;静电斥力作用;空间位阻斥力作用;水化膜润滑作用;引气隔离"滚珠"作用。并且,指出减水剂的种类不同,所具有的分散减水作用力的种类及各作用力的大小也不同。结合减水剂作用机理,对新型高效减水剂应具有的特性及其合成方法,以及通过复合使用高效减水剂控制混凝土坍落度损失的方法和原理进行了讨论。

In this paper,on the basis of the detailed analysis of molecule structure and absorption characteristics of plasticisers on cement particles,the action mechanisms of concrete plasticisers are summed up as the following five aspects,i.e.reducing the interfacial energy of solidliquid,static electric repulsion,steric hindrance repulsion,hydratedfilm lubrication action and the separating action of bubbles resulting from airentrance.Based on the mechanisms of plasticisers,those about the needed characteristics and synthesizing methods of new superplasticisers,and the controlling methods of slump loss for concrete by compounding superplasticisers have been discussed.