Shi Xiaonan, Wu Baiqian, Dong Xuechao, Zhang Qian, Lu Wei, Chen Xiaolin
School of Statistics and Data Science, Qufu Normal University, Qufu, Shandong 273165, China.
Key Lab of Mine Disaster Prevention and Control, School of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao, Shandong 266590, China.
ACS Omega. 2024 Jun 20;9(26):28253-28267. doi: 10.1021/acsomega.4c01502. eCollection 2024 Jul 2.
A composite gel material with an interpenetrating network structure was formed using the chemical cross-linking method. The viscosity, yield stress, and thixotropy of a poly(vinyl alcohol)/carboxymethyl cellulose/gelatin (PVA/CMC/Gel) composite gel slurry with different ratios were tested using a viscometer, and the interaction between the surface of the gelling agent and the cross-linking agent was analyzed by calculating the frontline orbital energy of a single polymer material molecule. The seepage diffusion characteristics of the composite gel in a goaf were then studied through a numerical simulation. The results indicate that the PVA/CMC/Gel composite gel exhibits shear thinning behavior following the power law model and behaves as a pseudoplastic fluid. The optimal ratio for the composite gel at 30 °C is determined as follows: 30 wt % for the gelling agent (PVA/(Gel + CMC) = 20:10), 4 wt % for the cross-linking agent, 3.09 wt % for the carbide slag, 7.5 wt % for the alcohol amine solution, and 0.5% sodium dodecyl sulfonate + 0.1% alkyl glycoside for the foaming agent. Gel exhibits the lowest energy band gap (0.096 eV), indicating strong reaction activity and strong reaction with the cross-linking agent (sodium tetraborate). PVA has the largest energy band gap (0.238 eV), strong molecular stability, and weak reaction with the cross-linking agent (sodium tetraborate). When the dip angle of the goaf is 4° and the injection time is 40 min, the composite gel tends to diffuse more easily along the dip. The investigation into the rheological properties of the PVA/CMC/Gel composite gel holds significant importance in the design of coal mine pipeline transportation and understanding diffusion flow in goaf.
采用化学交联法制备了具有互穿网络结构的复合凝胶材料。使用粘度计测试了不同比例的聚乙烯醇/羧甲基纤维素/明胶（PVA/CMC/Gel）复合凝胶浆料的粘度、屈服应力和触变性，并通过计算单一高分子材料分子的前线轨道能量分析了胶凝剂与交联剂表面之间的相互作用。然后通过数值模拟研究了复合凝胶在采空区的渗流扩散特性。结果表明，PVA/CMC/Gel复合凝胶遵循幂律模型呈现剪切变稀行为，表现为假塑性流体。30℃时复合凝胶的最佳配比确定如下：胶凝剂30 wt%（PVA/(Gel + CMC) = 20:10），交联剂4 wt%，电石渣3.09 wt%，醇胺溶液7.5 wt%，发泡剂为0.5%十二烷基磺酸钠 + 0.1%烷基糖苷。明胶的能带隙最低（0.096 eV），表明其反应活性强，与交联剂（硼砂）反应强烈。聚乙烯醇的能带隙最大（0.238 eV），分子稳定性强，与交联剂（硼砂）反应较弱。当采空区倾角为4°且注入时间为40 min时，复合凝胶更容易沿倾角方向扩散。对PVA/CMC/Gel复合凝胶流变特性的研究对于煤矿管道输送设计以及理解采空区扩散流动具有重要意义。
