纳米二氧化硅原位增强亲水性聚氨酯注浆材料的制备与性能研究

Properties of nanosilica-reinforced polyurethane by in-situ preparation and its application in polyurethane grouting

以异氰酸酯和高亲水性聚醚多元醇为原料,合成了亲水性聚氨酯预聚体浆液,并利用硅酸钠为硅源和预聚体反应,原位制备了纳米二氧化硅增强亲水性聚氨酯注浆材料固结体。应用FTIR-ATR、XRD和TEM对固结体的结构与性能进行了测试与表征,探讨了原位生成的纳米二氧化硅对亲水性聚氨酯注浆材料固结体性能的影响。结果表明,原位生成的纳米二氧化硅均匀的分散在聚氨酯中,并与聚氨酯网络以化学键方式结合,提高了固结体的力学性能。经过井下堵水中试工程试验以及后续的观察,纳米二氧化硅增强聚氨酯复合材料具有较高的实际堵水效率。

The prepolymer of hydrophilic polyurethane is synthesized by diisocyanate and polyether polyol, and then the polyurethane prepolymer blends with sodium silicate solution to prepare nanosilica-reinforced hydrophilic polyurethane composites(HPU/nano-Si O2) via in-situ reactions. The FTIR-ATR and X-ray diffraction(XRD) are employed to confirm the existence of the nano-Si O2 and its chemical bond to HPU chain, and the size and dispersion of nano-Si O2 in HPU matrix are investigated by transmission electron microscopy(TEM). The gel time of the mixture consisting of HPU prepolymer and sodium silicate solutions and the mechanical properties of HPU/nano-Si O2 composites are also tested. The results show that the particles of nano-Si O2 disperse homogeneously in the HPU matrix, and the nano-Si O2 combines with HPU chains by chemical bonds to form HPU/nano-Si O2 composites. What's more, the gel time of HPU and sodium silicate solution blend increases compared to that of the blend of HPU and water, and the compression strength of HPU/nano-Si O2 is improved effectively than that of pristine HPU, so the HPU prepolymer can react with sodium silicate solutions to produce the nanosilica reinforced hydrophilic polyurethane grout, which has high ability and efficiency to form adequate plugs for underground water though the plugging project of coal mine.