| 摘要: |
| 以三乙醇胺（TEA）和三聚磷酸钠（STPP）为助磨剂，针对分别掺加2种助磨剂的硅酸盐水泥熟料和石膏混合体系进行粉磨，研究了所制备水泥的颗粒粒径和表面性质.结果表明：TEA和STPP均可改善水泥的粒径分布，使得粒径小于32 μm的颗粒占比明显增加；TEA通过酸碱作用力吸附在水泥熟料矿物相铝酸三钙（C3A）和铁铝酸四钙（C4AF）表面，降低了水泥颗粒的极性表面能及其总表面能占比；TEA通过范德华力吸附于水泥熟料矿物相硅酸三钙（C3S）和硅酸二钙（C2S）表面，降低了水泥颗粒的色散表面能和总表面能，从而阻止了粉磨过程中的颗粒团聚和断面愈合；STPP的3个同侧O原子与颗粒表面Ca2+、Al3+和Fe3+络合，剩余2个未饱和成键的O原子则伸向外部，显著增加了水泥颗粒的极性表面能及其总表面能占比，以及碱性常数，从而通过电性相斥作用促进了颗粒的破碎和分散；此外，STPP中游离的Na+进入水泥熟料矿物相的晶格孔穴中，或与晶格中的Ca2+发生置换，加剧了矿物相的晶格畸变和内部化学键的断裂. |
| 关键词: 助磨剂 三乙醇胺 三聚磷酸钠 水泥颗粒 表面性质 |
| DOI：10.3969/j.issn.1007-9629.2022.07.010 |
| 分类号:TU528.01 |
| 基金项目:国家自然科学基金资助项目（51678441， 52108240）；上海市科委项目（19DZ1202702，19DZ1201404）；上海市建委专项课题（住建管2021-001-002）；住建部项目（K20200988）；重庆市科技局专项（cstc2020kqjscx-phxm1594）；上海市科委（上海市外专局）项目（22WZ2502400） |
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| Effect of Triethanolamine and Sodium Tripolyphosphate as Grinding Aids on the Surface Properties of Cement Particle |
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DONG Yaowu1,2, SUN Zhenping2,3, ZHOU Xiaoyang1, YANG Sheng4, SETZER Max Josef5
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1.Hubei Lianjian New Building Materials Co.， Ltd.， Wuhan 430080， China;2.Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education， Tongji University， Shanghai 201804， China;3.School of Materials Science and Engineering， Tongji University， Shanghai 201804， China;4.Tibet Wuyang Industry Co.， Ltd.， Lhasa 850000， China;5.Institute for Building Physics and Materials Science， University of Duisburg-Essen， Essen 45121， Germany
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| Abstract: |
| Cement specimens were prepared by grinding the Portland cement clinker and gypsum blended system with triethanolamine （TEA） and sodium tripolyphosphate （STPP） as grinding aid respectively. The particle size distribution and surface properties of cement specimens were tested. The results show that both TEA and STPP can improve the particle size distribution， and the proportion of fine particles （<32 μm） increase significantly. The adsorption of TEA molecules on the surface of cement clinker minerals， tricalcium aluminate （C3A） and tetracalcium aluminoferrite （C4AF）， by acid-base force led to a significant decrease in specific surface energy and its proportion to total surface energy. The adsorption of TEA molecules on the surface of cement clinker minerals， tricalcium silicate （C3S） and dicalcium silicate （C2S） by van der Waals force decrease the dispersive surface energy and the total surface energy， which prevents agglomeration and fracture healing of the particles during the process of grinding. The adsorption of STPP molecules on the surface of cement particle led to a significant increase in specific surface energy， its proportion to total surface energy and the alkaline constant since the three O atoms in STPP molecule form stable complexes with the Ca2+， Al3+ and Fe3+ on the particle surface， and the remaining two O atoms outstretch. Thus， the electrical repulsion promotes the fragmentation and dispersion of particles. At the same time， the free Na+ in STPP enters the lattice holes of cement clinker minerals， which aggravates the crystal lattice distortion and accelerates the fracture of crystal bonds. |
| Key words: grinding aid triethanolamine（TEA） sodium tripolyphosphate（STPP） cement particle surface characteristic |
