促聚合与生物矿化改善轨道板用钠水玻璃性能  

Improving the Performance of Sodium Silicate for Track Slab by Promoting Polymerization and Biomineralization

作　　者：李茂红[1] 潘璋 凌晨博 姚宁[2] 李书娴 王平[1] LI Maohong;PAN Zhang;LING Chenbo;YAO Ning;LI Shuxian;WANG Ping(MOE Key Laboratory of High-Speed Railway Engineering,Southwest Jiaotong University,Chengdu 610031,China;School of Life Science and Engineering,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]西南交通大学高速铁路线路工程教育部重点实验室,四川成都610031 [2]西南交通大学生命科学与工程学院,四川成都610031

出　　处：《西南交通大学学报》2019年第4期879-884,共6页Journal of Southwest Jiaotong University

基　　金：国家杰出青年科学基金资助项目(51425804);国家自然科学基金资助项目(51708458)

摘　　要：为改善高铁轨道板涂料用钠水玻璃力学强度和耐水性,通过添加Ca(H2PO4)2,达到促进钠水玻璃生物矿化、提高硅氧聚合程度的目的.首先在钠水玻璃中添加Ca(H2PO4)2制作样品,以未添加Ca(H2PO4)2的样品作空白对照;然后用万能材料试验机、耐水性试验检测样品性能,并用X-射线衍射仪、傅里叶红外光谱仪、固体核磁共振仪测试其微观组成和结构.研究结果表明:Ca(H2PO4)2添加导致钠水玻璃力学强度提高160%,耐水性由浸水2 h完全溃散提高至浸水7 d无明显损坏;促使钠水玻璃仿生矿化形成力学强度高、耐水性好的人体骨主要无机成分Ca8H2(PO4)6?H2O-NaHCO3-H2O;增强钠水玻璃中硅氧的聚合,使之形成耐水性更好的硅氧聚合体.可推断得,添加Ca(H2PO4)2可明显提高钠水玻璃凝结硬化后力学强度和耐水性,具有应用于轨道板涂料的前景.To improve the mechanical strength and water resistance of sodium silicate used for track slab coating in high-speed railways, Ca(H2PO4)2 was added into sodium silicate to promote biomineralization and polymerization of silica gel. First,Sodium silicate modified by Ca(H2PO4)2 was prepared,using sodium silicate without adding Ca(H2PO4)2 as a control. The property of the sample was tested by universal material testing machine and water resistance testing;and the composition and microstructure of the sample were characterized by X-ray diffractometer(XRD),Fourier-transform infrared spectrometer(FTIR),and 29 Si nuclear magnetic resonance instrument(29 Si NMR). Results show that the addition of Ca(H2PO4)2 increased mechanical strength by 160% and improved water resistance from 2 h to more than 7 d for sodium silicate;adding Ca(H2PO4)2 into sodium silicate led to biomineralization by forming Ca8 H2(PO4)6·?H2 O-NaHCO3-H2 O,which is the main inorganic component of Human bone with high mechanical strength and good water resistance;and Ca(H2PO4)2 promoted the polymerization of silica gel to form silica oxygen polymer with higher mechanical strength and better water resistance in sodium silicate. It is concluded that the addition of Ca(2 PO4)2 greatly improved the mechanical strength and water resistance of sodium silicate after setting and hardening,which may have promising applications in track slab coating.

关 键 词：聚合 生物矿化 钠水玻璃 耐水性 力学强度 

分 类 号：TU52[建筑科学—建筑技术科学] TU58