轨道板用热反射涂料的磷酸钙界面仿生增强与热反射机理研究

The obvious temperature deformation of track slab caused by solar radiation in summer has an effect on the operation safety of the high-speed trains. Hopefully heat reflective paint will reduce such harm when the paint used for track slab has to withstand the huge wind from the high-speed running trains. Therefore, it is urgent to explore the bonding enhancement mechanism between paint and track slab as well as the key factors impacting the heat reflection performance of the paint. .In this application, the methods to be employed is optimizing calcium phosphate (CaP) to regulate the gel growth of sodium silicate, combine the biomimetic mineralization, and produce the chemical bond in multiple components in sodium silicate/CaP/track slab so that the interfacial bond strength of paint/track slab will be improved. Macroscopic and microscopic evaluation methods would be used to investigate the effect of CaP both on the macroscopic and microscopic performance of sodium silicate and on the composition, construction, morphology and bond strength in the interface of sodium silicate/track slab. Then, the interfacial biomimetic reinforcement mechanism will be revealed. In view of the solar spectrum and incident Angle, a modified spectrometer will be used to study the heat reflection of the paints with different raw material properties and distribution under multiple angles of incidence and wavelength. And the key factors and internal mechanism that affect the heat reflection performance will be explored as well. The findings are expected to provide the theoretical reference for enhancing the interfacial bond strength and heat reflection performance in similar research, and the technical support for developing heat reflection paint used for the track slab.

夏季太阳辐射致高铁轨道板产生明显温度变形，影响高铁列车安全运行。热反射涂料有望减小上述危害，而涂覆于高铁轨道板则需承受高铁列车运行产生的巨大风力。因此，迫切需要探明涂料与轨道板粘结增强机理；影响涂料热反射性能的内在机理。.本申请欲采用优选磷酸钙（CaP）调控水玻璃凝胶生长、合并仿生矿化、集水玻璃/CaP/轨道板多元组分共同参与化学键合的方法，增强水玻璃型热反射涂料/轨道板界面粘结强度。采用材料学、化学、物理学宏微观评价方法，进行CaP对水玻璃宏微观性能影响，对水玻璃/轨道板界面组成、结构、形貌及粘结强度等影响的研究；揭示界面仿生增强机理。 欲采用改装光谱仪的方法，针对太阳光谱和入射角，进行多入射角、多波长下，具有不同原材料性状和分布的涂料热反射性能研究；并探索对涂料热反射性能产生影响的关键因素和内在机理。为增强界面粘结和热反射性能的类似研究提供理论借鉴，为轨道板用热反射涂料研发提供技术支撑

夏季太阳辐射致高铁轨道板产生明显温度变形，影响高铁列车安全运行。太阳热反射涂料有望减小上述危害，而涂覆于室外用高铁轨道板则需具有良好的耐水性，需承受高铁列车运行产生的巨大风力。因此本项目先进行了提高涂料耐水性和粘结强度的相关研究，然后制作了。.为减小污染和减小涂料中非反射颜料对太阳反射率的影响，采用透明的水玻璃做涂料基料。同时轨道涂料需具有良好的耐水性和粘结强度。而水玻璃是一种气硬性胶凝材料，遇水易溶解破坏。故本项目首先进行了提高水玻璃耐水性和粘结强度的研究。分别采用CaO和Ca(H2PO4)2对水玻璃进行改性；实验结果表明CaO改性水玻璃力学强度提高77%，耐水性也明显提高，主要归因于导致水玻璃中的硅氧聚合体解聚、重组并限制聚合；同时形成耐水性较好、力学强度较高的CaO.xSiO2.yH2O凝胶。Ca(H2PO4)2添加导致水玻璃力学强度提高超过200%，耐水性提高至浸水7d无明显损坏，主要归因于可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；同时增强水玻璃中硅氧的聚合形成耐水性更好的硅氧聚合体。可初步推断，采用CaO和Ca(H2PO4)2改性可明显提高水玻璃凝结硬化后力学强度和耐水性，具有应用于高铁轨道板涂料的前景。.目前，已以水玻璃为基料，添加相应的改性剂作固化剂成功制备出太阳热反射涂料，研究结果表明，该涂料具有大于90%的太阳反射率，能承受超过840小时的浸水测试而粘结强度基本不变，具有良好的耐水性，并具有满足国标要求的粘结强度。这主要归因于改性剂促进水玻璃中的硅氧键聚合，涂料中的二氧化钛有高的太阳反射率，并不被涂料中其它组分所削弱。并进一步采用机械活化法活化改性剂，发现使可粘结强度再提高60%左右。本项目的研究为类似研究和应用提供了理论借鉴和技术支持。