废弃橡胶改性水泥基材料研究进展

Research progress of waste rubber modified cement-based materials

橡胶颗粒具有良好的吸能变形能力,将橡胶颗粒掺入水泥基中可以有效提高材料的韧性,同时能够增强水泥基的抗冻性、抗开裂、抗冲击等性能。但由于橡胶颗粒是一种憎水物质,导致橡胶与水泥浆液的界面粘结力较弱,水泥基材料的强度有所下降,因此对橡胶水泥基材料进行化学与物理改性研究。结果表明,改性橡胶通过两种方式来增强水泥基材料的性能:其一,改性剂通过溶解橡胶颗粒表面的杂质和在其表面形成一层薄膜来提高橡胶的亲水性;其二,改性剂与水化产物发生反应,形成有效的化学交联,使橡胶颗粒与水泥浆液形成紧密连接。同时研究发现,橡胶颗粒与纤维聚合物对水泥基材料的增强增韧有协同作用。

Rubber particles have good energy absorption and deformation ability.The incorporation of rubber particles into cement base can effectively improve the toughness of the material,and enhance the freezing resistance,cracking resistance,impact resistance and other properties of cement base.However,because rubber particles are a kind of hydrophobic substance,the interface bonding force between rubber and cement slurry is weak,and the strength of cement-based materials is decreased.Therefore,chemical and physical modification of rubber cement-based materials is studied.The results show that the modified rubber can enhance the properties of cement-based materials in two ways.First,the modifier can improve the hydrophilic of rubber by dissolving the impurities on the surface of rubber particles and forming a film on the surface.Second,the modifier reacts with the hydration product to form an effective chemical cross-link,so that the rubber particles form a close connection with the cement slurry.At the same time,it is found that rubber particles and fiber polymers have synergistic effect on the strengthening and toughening of cement-based materials.