煤矿堵漏风仿生材料的自愈合机理研究

Excellent air-leakage blocking material plays a pivotal role in preventing coal spontaneous combustion that severely restricts the safe in coal mines. For solving fracture problem of existing air-leakage blocking materials that easily occurs under the action of mine pressure, a biomimetic self-healing air-leakage blocking material is developed in this project. The material has characteristics such as self-detection and self-healing of fractures, low-cost and environment-friendly preparation. Inspired from biomimetic self-healing materials and resourcing by waste recycling, we utilize some solid wastes like carbide slag and brine sludge to prepare matrix materials which can help the operators to control the fractures, and to insert internally capsules containing healing agents in order to prepare the biomimetic self-healing air-leakage blocking material. On the basis of a full analysis of the composition of the solid waste, we study the curing mechanism and determine the mechanical characteristics of the material that can help to control fractures. With an exhaustive screening of the wall material of capsule and the healing agents, the variation law of the self-healing capsule system is analyzed. The microstructure, the mechanical performance, and self-healing efficiency of the biomimetic material are analyzed using modern testing methods in order to clarify the regulation mechanism of the capsule composition on the structure and the performance of the biomimetic material. Starting from the capsule rupture, the infiltration of the healing agent, the curing process, and other aspects, the self-healing mechanism of biomimetic materials is clarified. With the application of laboratory and industrial tests, the air-leakage blocking characteristics of the biomimetic material are clarified, which can provide a theoretical basis for the application of a biomimetic material in the field of air-leakage blocking materials for coal mines.

煤炭自燃严重制约了煤矿的安全生产，制备优异的堵漏风材料是防治煤炭自燃的关键。本项目针对现有堵漏风材料在矿压作用下容易产生漏风裂隙的问题，提出了煤矿堵漏风仿生自愈合材料。该材料具有自动检测、自动愈合、价格低廉、绿色环保等特点。本项目以“仿生自愈合”和“废物资源化”为指导思想，利用电石渣、盐泥等固废物制备裂纹可控基体材料，并内置含有愈合剂的胶囊，构建“煤矿堵漏风仿生自愈合材料”。在全面分析固废物成分的基础上，研究裂纹可控材料的固化机理与力学特性；科学筛选胶囊的壁材与愈合剂，分析胶囊自修复体系的性能变化规律；借助现代化测试手段，分析仿生材料的微观结构、力学性能和自愈合效率，阐明胶囊的组成对仿生材料的结构、性能的调控机制；从胶囊的破裂，愈合剂的流出、固化等环节入手，揭示仿生材料的自愈合机理；通过开展实验室试验和煤矿工业性试验，阐明仿生材料的堵漏风特性，为该材料在煤矿堵漏风领域的应用提供理论基础。

本项目针对现有堵漏风材料在矿压作用下容易产生漏风裂隙的问题，采用实验室试验、理论分析和数值模拟的方法，研发了一种煤矿堵漏风仿生自愈合材料。首先，在碱激发体系激发下，以电石渣、粉煤灰、脱硫石膏和高炉水渣为主要原料，并在其中掺入PVA纤维，制备了一种无机绿色裂纹可控型基体材料。研究了电石渣、粉煤灰、高炉水渣、脱硫石膏等材料的最优配比，筛选并优化了碱性激发剂，阐明了基体材料力学性能的变化规律，揭示了电石渣、粉煤灰等材料的胶凝固化机理；研究了PVA纤维对基体材料的力学性能和微观结构的影响，明确了PVA纤维的最优掺量，分析了预压损伤条件下裂纹的开裂特点，阐明了PVA纤维的增韧机理。研究了阻燃剂对愈合剂的流动特性、固化时间、粘结强度的影响规律，探讨了改性愈合剂的固化反应动力学与固化机理，分析了常见壁材（玻璃、陶瓷等）的物理化学特性，探讨了愈合剂与胶囊壁材的化学相容性，明确了胶囊自修复体系的最优组合。研究了胶囊在混合、搅拌过程中的存活率，分析了胶囊的存活率与胶囊壁厚、搅拌速度的关系；研究了胶囊在基体材料中的受力情况和破裂行为，分析了裂纹可控材料与胶囊的断裂匹配性，阐明了胶囊的大小和掺量对仿生材料的微孔结构、力学性能以及自愈合效率的影响，揭示了胶囊的组成对仿生材料的结构、性能的调控机制。研究了仿生材料中胶囊的破裂条件，建立了胶囊破裂的力学方程，分析了愈合剂的流变特性，探讨了愈合剂的固化机理，阐明了愈合剂的固化产物与基体材料的的粘结机制，从胶囊的破裂、愈合剂的流出、固化等过程深入揭示了仿生材料的自愈合机理。研究表明，愈合剂能够封堵裂缝并在一定程度上提高基体材料的刚度，固化后的愈合剂能与基体材料中的C3S和C2S紧密粘合在一起。本项目的研究成果为仿生自愈合材料在煤矿堵漏风领域的应用提供了相关理论基础。