The use of waste plastic as aggregate in cement composites can solve the problem of the disposal of waste plastics in a sustainable way, and it reduces the need for extracting traditional materials like sand and gravel, which causes erosion and environmental degradation. The reaction of plastics with certain oxidizing chemicals is believed to result in chemical or electrostatic bonding between the plastic surface and the cement matrix. The present study investigates the effect of pre-treating plastic aggregates (with sodium hydroxide and sodium hypochlorite) on certain engineering properties of cement mortars. Five types of recycled plastics are used as partial sand replacements. Two replacement levels (5 and 15% by volume of sand) and two methods of chemical treatment are investigated. The results showed a decline in the properties of mortars made with chemically treated plastic aggregates: the addition of treated plastic aggregates makes the matrix porous, thereby degrading the mechanical properties. This behaviour intensifies with increasing plastic dosage. The polyoxymethylene (POM) and acrylonitrile butadiene styrene (ABS) plastic mortars performed best, while the polyethylene terephthalate (PET) mortars achieved poor results. Water-rinsing the treated aggregates removed reactive species from the plastic surface, and neutralized the matrix alkalinity resulting in comparatively less porous structures.

在水泥复合材料中使用废塑料作为骨料可以解决可持续处理废塑料的问题，并且减少了对传统材料（如沙子和砾石）的提取需求，这会导致侵蚀和环境恶化。据信，塑料与某些氧化性化学物质的反应会导致塑料表面与水泥基体之间发生化学键合或静电键合。本研究调查了预处理塑料骨料（用氢氧化钠和次氯酸钠）对水泥砂浆某些工程性能的影响。五种类型的再生塑料被用作部分砂的替代品。研究了两种替代水平（按体积计为5％和15％的沙子）和两种化学处理方法。结果表明，用化学处理过的塑料骨料制得的砂浆的性能有所下降：处理过的塑料骨料的添加使基体具有多孔性，从而降低了机械性能。随着塑料剂量的增加，这种行为会加剧。聚甲醛（POM）和丙烯腈丁二烯苯乙烯（ABS）塑料砂浆的效果最佳，而聚对苯二甲酸乙二醇酯（PET）砂浆的效果较差。用水冲洗处理过的聚集体，从塑料表面去除了反应性物质，并中和了基质的碱度，从而形成了相对较少的多孔结构。聚甲醛（POM）和丙烯腈丁二烯苯乙烯（ABS）塑料砂浆的效果最佳，而聚对苯二甲酸乙二醇酯（PET）砂浆的效果较差。用水冲洗处理过的聚集体，从塑料表面去除了反应性物质，并中和了基质的碱度，从而形成了相对较少的多孔结构。聚甲醛（POM）和丙烯腈丁二烯苯乙烯（ABS）塑料砂浆的效果最佳，而聚对苯二甲酸乙二醇酯（PET）砂浆的效果较差。用水冲洗处理过的聚集体，从塑料表面去除了反应性物质，并中和了基质的碱度，从而形成了相对较少的多孔结构。