有机助磨剂对水泥性能的影响及其有机水泥化学分析(英文)

现代水泥、混凝土中大量使用化学外加剂,特别是有机化合物和高分子聚合物化学外加剂,例如：水泥助磨剂、混凝土超塑化剂、引气剂、增稠剂等,大量有机物的加入改变了水泥水化过程、水化动力学、微观结构的发展,传统的水泥混凝土化学不再能很好地解释其微观结构与宏观性能的关系。为此,提出一个新兴的水泥混凝土化学的补充分支—有机水泥化学,在未来的水泥混凝土研究中该给予更多的重视。以有机化学外加剂—助磨剂为例,说明其对水泥水化动力学、水化产物形态以及水泥浆体的超塑化剂需求量、流变特性、强度发展等宏观性能的影响。水泥中加入微量的助磨剂,不仅改变了水泥颗粒分布,还改变了水化动力学,促进起始离子的溶解和铝酸钙（C3A）和铁铝酸钙（C4AF）的早期水化,明显地提高早期强度和28 d强度。助磨剂吸附在水泥表面改变了水泥的表面性质,其中助磨剂和Ca2＋、Fe2＋螯合起关键作用。

Effect of Organic Grinding Aids on Cement Properties and the Analysis via Organic Cement Chemistry

The majority of chemicals,especially organic chemicals and polymers are used as grinding aids,superplasticizers,air en-training agents,thickeners,etc.in cement and concrete engineering.The cement hydration process,kinetics,microstructural devel-opment,relation between microstructure and macroscopic properties of cement and concrete could be substantially altered when the organic substances are added into cement and concrete,which could not be analyzed by the conventional theory on chemistry of ce-ment and concrete.A novel branch to chemistry of cement and concrete,namely,the ’organic cement chemistry’,were proposed for the research of cement and concrete.The effects of organic additives like grinding aids on the kinetics of cement hydration,morphol-ogy of cement hydrates as well as on the macroscopic properties such as superplasticizer demand,rheological properties,strength development etc were exemplified.It was indicated that besides the particle size distribution,the small amount of grinding aids added into cement could alter the kinetics of cement hydration,accelerate the initial dissolution of ions and early hydration of C3A and C4AF,and finally enhance the early strength and even 28-days strength to a visible extent.The surface modification via the adsorption of organic grinding aids on cement surface and the chelating effect between the grinding aids and Ca2+,Fe2+ should be analyzed based on the proposed ’organic cement chemistry’.