核壳纳米粒子改性混凝土表层性能研究

Concrete surface treatment is an effective way to improve its own durability. At present, coating materials composed of organic materials are faced with many limitations. Developing new generation coating materials and revealing their mechanism is of significance for further extending the service life of concrete under the severe condition. Through the study of the structure-performance relationship between the core-shell nanoparticles and the permeability of concrete, this project elucidates the design and preparation methods of the core-shell nanoparticles structure, which is suitable for concrete surface coating. By the In-depth study of the mechanism of microstructure control mechanism, proposed the new method that constructs the topological holes and bionic micro-structure in the concrete surface, and exploring temperature/ humidity/ion response mechanism of the nano-modified microstructure. To explore the action mechanism of nanoscale, we simulate the characteristics of the solid-liquid interface, the interface of solid-air interface and the network structure of atomic structure of the interface, Based on the molecular dynamics.The project provides new research ideas for nano-particle modified concrete and also provides an important theoretical basis for the preparation and application of concrete nano-coating materials.

混凝土表面处理是提升自身耐久性的一个有效方式，目前以有机材料为主体的涂覆材料面临诸多局限，研发新型的表面防护涂覆材料并揭示其作用机理，对进一步延长混凝土在严酷环境下服役寿命具有重要意义。本项目通过研究核壳纳米粒子涂层与混凝土渗透性能之间构效关系，阐明适宜于混凝土表层涂覆的核壳纳米粒子结构设计原理与制备方法。深入研究微结构调控机理机制，提出借助核壳纳米粒子特性，在混凝土表层构造拓扑孔洞和仿生微结构新方法，并探索纳米改性微结构温度/湿度/离子响应机制。基于分子动力学，模拟固-液界面，固-气界面界面能与界面原子结构网络变化特性，揭示纳观尺度作用机理。本项目为纳米粒子改性混凝土提供了新的研究思路，也为混凝土纳米涂层材料制备与应用提供了重要理论基础。

混凝土表面处理是提升自身耐久性的重要方式，同时也是纳米粒子在本领域的一个重要应用场景。开发新型纳米防护剂对提升混凝土耐久性和加快纳米改性技术在本领域的应用有重要意义。本项目利用有机-无机杂化的优点，制备了基于小分子修饰的核壳纳米粒子。将核壳纳米粒子以内掺法和直接涂覆法的方式应用于混凝土表层处理。研究了不同侵蚀环境下纳米粒子涂层对基体渗透性影响。考察了紫外老化对不同类型核壳纳米粒子处理效果影响，揭示了耐紫外老化的核壳纳米粒子作用机制。基于微观分析和热力学模拟手段，研究了不同侵蚀环境下纳米改性表层微结构的矿物组成、形貌和孔隙结构变化，发现了核壳纳米粒子具有稳定碳硫硅钙石，调节氢氧化钙结晶取向，和优化毛细孔隙等一系列作用。考察了核壳纳米粒子温度和紫外响应机制，揭示了其火山灰反应速率的可调节性。基于分子动力学，探讨了无氟有机小分子和含氟有机小分子在微纳尺度上对CSH界面改性作用的异同。本项目研究结果为纳米粒子在不同环境下混凝土表层改性中的应用提供了实验和理论参考。