Photocatalytic gypsum plasters – studies of air cleaning properties and selected technical parameters

This study aims to investigate the feasibility of using industrial waste plastics, polypropylene (PP), polyethylene (PE) and polyamide (PA), obtained from recycling factory, as reinforcement for mortar. As one of the main problems of using waste plastics in cementitious composites is the hydrophobic properties of the sur- face of the plastics, because it prevents the formation of adequate interfacial adhesion with cement paste. Surface treatment of waste plastics was applied using diluted solution of isopropanol. Three parameters were considered when designing the mortar mixtures; type of waste plastic (PP, PE, PA), their addition ratio and surface treatment. Bending and compression tests were conducted. 1.5% volume addition of PP and PE to mortars the flexural strength was increased, however, surface treatment of waste plastics did not affected this strength. As the waste plastic volume ratio increased, the flexural toughness of mortars reinforced with PP, PE and PA plastics was also increased. For the 1.5% volume ratio, there was the increase of flexural toughness with respect to the reference mortar and the highest influence had the PP. For the untreated waste plastics, there was significant increase in flexural toughness, while reduction in the compressive strength and compressive toughness was found, however, this surface treatment enhanced the compressive strength and compressive toughness with respect to untreated plastics. Waste plastics can be used for mortars and concretes reinforcement to improve the ductility and energy absorption capacity while eliminating pollution and regaining them in the economy as a structural material.