Kang Hyeju, Kang Sukpyo, Lee Byoungky
Department of Construction Engineering, Woosuk University, Jincheon 27841, Korea.
Department of Architecture, Woosuk University, Jincheon 27841, Korea.
Materials (Basel). 2021 Sep 18;14(18):5407. doi: 10.3390/ma14185407.
In this study, the compressive strength and water contact angle of mortar specimens prepared by mixing two types of water repellent with ordinary Portland cement (OPC) and rapid-hardening cement mortar were measured before and after surface abrasion. In addition, the hydration products and chemical bonding of cement mortar with the repellents were examined using X-ray diffraction (XRD), thermogravimetry-differential thermal analysis (TG-DTA), and Fourier-transform infrared spectroscopy (FT-IR) to evaluate the performance of these cement mortar mixtures as repair materials. We found that the fast-hardening cement mortar mixture containing the oligomer water repellent showed the best performance with a high compressive strength and large water contact angle. With the oligomer water repellent, the rapid-hardening cement mortar mixture showed contact angles of 131° and 126° even after a 2 mm abrasion, thereby confirming that the water repellent secured hydrophobicity through strong bonding with the entire cement mortar as well as its surface. The compressive strengths were found to be 34.5 MPa at 3 h and 54.8 MPa at 28 days, confirming that hydration occurred well despite the addition of water repellent.
在本研究中，对通过将两种憎水剂与普通硅酸盐水泥（OPC）和快硬水泥砂浆混合制备的砂浆试件在表面磨损前后的抗压强度和水接触角进行了测量。此外，使用X射线衍射（XRD）、热重-差热分析（TG-DTA）和傅里叶变换红外光谱（FT-IR）研究了水泥砂浆与憎水剂的水化产物和化学键合，以评估这些水泥砂浆混合物作为修复材料的性能。我们发现，含有低聚物憎水剂的快硬水泥砂浆混合物表现出最佳性能，具有高抗压强度和大的水接触角。使用低聚物憎水剂时，快硬水泥砂浆混合物即使在磨损2mm后仍显示出水接触角为131°和126°，从而证实了憎水剂通过与整个水泥砂浆及其表面的强键合确保了疏水性。发现抗压强度在3h时为34.5MPa，在28天时为54.8MPa，证实了尽管添加了憎水剂，但水化仍进行得很好。
