Sustainable construction via novel geopolymer composites incorporating waste plastic of different sizes and shapes

This research investigated the influence of shape and size of plastic waste on the fresh-state and hardened-state properties of geopolymer (GP) mortars. Geopolymer composites were prepared using fly ash and waste plastic bottle composed of polyethylene terephthalate (PET). PET was introduced in form of shredded flakes, strips, and grinded particles of different sizes. The flowability and mechanical properties of PET/geopolymer mortars improved with decreasing size of the plastic aggregates. PET grinded particles were found to be the most effective form of aggregate. Although the geopolymer composites containing PET particles had workability and flexural strength close to those of the control mixture, their compressive strength and splitting tensile strength were noticeably lower due to poor interaction between PET particles and the matrix. The latter issue could potentially be addressed by enhancing the adhesion at the interface of PET particles and geopolymer mortars.

Automated summary

This research investigated the influence of shape and size of plastic waste on the properties of geopolymer mortars. The study found that smaller plastic aggregates improved the flowability and mechanical properties of the geopolymer mortars. However, the presence of PET particles resulted in lower compressive strength and splitting tensile strength due to poor interaction with the matrix. Enhancing the adhesion between PET particles and geopolymer mortars could potentially address this issue.