Recycling of Post-Consumer PET Plastic Waste Bottles in Non-Cement Composites for Construction Applications

Abstract

This study focused on developing and evaluating non-cement composites for construction applications using post-consumer polyethylene terephthalate (PET) plastic bottles. A total of two types of non-cement composites, namely, pervious PET composite (PPC) and PET soil composite (PSC), were developed. In addition, nine PPC mixes and five PSC mixes were designed using different PET and soil contents. Using the mix designs, cylindrical samples of PPC and PSC were produced in mold by compacting a mixture containing molten PET and heated soil or aggregates or both in accordance with proportions determined from mix design. Dry cylindrical samples of PPC were tested for indirect tensile strength and permeability in a unique manner. On the other hand, dry PSC samples were tested for compressive strength and moisture susceptibility tests. A PET content of 7.5 % PET was found to provide maximum tensile strength values among all PPC samples tested in this study. It was also found that using PET alone in PPC mix is not strong enough in binding aggregates and, therefore, 10 % soil was found to provide maximum strength. Permeability values of PPC mix decreased with an increase in both PET and soil content. The developed PSC mixes produced higher compressive strength values as compared to control samples containing up to 10 % cement; 25 % PET content provided strength of approximately 4,690\xa0psi. Increase in PET content made PSC samples more ductile and moisture resistant. Overall, findings from this study indicate that PPC and PSC could potentially be used for construction applications and offer an effective technique for diverting a large amount of PET plastic from landfills and incinerators.