Use of PET resin and metakaolin in sustainable production of cement mortar

Abstract

In the 21st century, substantial growth in plastic consumption is observed worldwide, which has led to vast quantities of plastic waste. Polyethene terephthalate (PET) is one kind of plastic that is widely used packaging industry because of its advantages of being light in weight non-reactive to substance. This advantage increases the consumption of PET and leads to another problem of solid waste management. The chemical recycling of PET waste to form a low-cost polymer and used as a binder to replace cement and the mineral addition of metakaolin would be advantages for cement concrete or mortar. In this work, PET resin is prepared with a 30:70 PET to Glycol ratio and further added to 5%, 10% 15% as cement replacement with a curing agent. In addition to this, metakaolin was added by 10%, 20%, and 30% of the volume of cement as supplementary cementing material. The fresh and hardened properties were determined for various mixes. The flow of mortar increases as PET resin content increases. The addition of metakaolin reduces the flowability of mortar. The compressive and tensile strength is determined at 1,7 and 28-days of curing. The 1-day curing compressive strength is 80% of the targeted strength is achieved for 15% resin content specimen with and without metakaolin compared to standard cement mortar specimen. In comparison with compressive strength, the gain in tensile strength is more. As the PET content increases in the mix increases the tensile strength. The durability is assessed by water penetration resistance and abrasion resistance, and it is observed that the addition of 15% PET resin and 20% metakaolin increases the durability. The mix ratio of 1:3 is used; among all the mixes, 15% PET resin and 20% metakaolin content mix are found to be the optimum mix in all testing parameters. The cost analysis is carried out for the same mixture. The addition of PET Resin and Metakaolin reduces the cement consumption by 141 kg/m3 and there by a reduction in the CO2 emissions. It will help to achieve the objective of sustainable development.