MMA基混凝土修补材料的制备与性能

Synthesis and properties of MMA-based repair material for concrete

混凝土开裂是混凝土破坏最普遍的形式,如不及时对裂缝修补,将造成混凝土由表及里的破坏,严重影响混凝土的耐久性。因此,采用性能优良的修补材料进行修补,对提高混凝土工程的安全性和延长其使用寿命具有重要意义。甲基丙烯酸甲脂(MMA)基混凝土修补材料是由MMA和引发剂、增塑剂等合成的高分子聚合物,它具有粘度小、凝固体强度高、与混凝土粘结牢固等性能。通过对MMA基混凝土修补材料的合成,详细探讨了引发剂和增塑剂对材料粘度以及材料力学性能的影响。结果表明:引发剂浓度过大或过小,都会使材料的粘度变小,引发剂的适宜质量分数是0.6%～0.7%,增塑剂浓度的增加使粘度增大,修补材料的力学性能达到了修补混凝土的要求,变形性能良好,可以承受一定的荷载变形。

It is known that crack is the normal form of concrete deterioration. It will cause serious breakage gradually and will shorten the natural life cycle of the concrete structures if it is not mended in time. Therefore it is important to develop the suitable materials to repair concrete. MMA-based repair material for concrete is a kind of polymer made of MMA, initiator and plasticizer. It has excellent properties, such as low viscosity, high strength, high bonding strength to concrete and so on. It is more suitable for repairing finely cracked concrete. Synthesis and properties of MMA-based repair material for concrete was discussed. It was focused on the key factors influencing viscosity during the synthesis of the material and the properties were also investigated in detail. The results showed that viscosity will increase to a maximum and then decrease with the increase of initiator concentration. The optimum quantity of initiator was 0.7% of total weight. Plasticizer may enlarge the viscosity of material. The distortion and the mechanical properties of obtained material may satisfy to requirement of repair materials for concrete. The bending strength may reach 120.31MPa and the tensile strength 33.25 MPa, respectively.