Recycling polypropylene and polyethylene wastes in production of polyester based polymer mortars

Although polymers were originally seen as an option to replace other materials due to their physicochemical properties and low cost, they have become an environmental problem due to poor final disposal practices. For these reasons, in the presented investigation, impact of waste polypropylene (wPP) from bottle caps and waste polyethylene (wPE) from bottles, on mechanical characteristics of polymer mortars were observed. Mortars were produced with unsaturated polyester resin at 20% ratio and silica sand at 80% ratio. Sand was replaced with the wastes at three different ratios as 1, 2 and 3 wt% and sizes as 0.71, 1.4 and 2.38 mm. Observations exhibited improvement about 27% for compressive strength when adding wPP particles; 30% on the compressive deformation (adding wPE) as well as 82% on the flexural deflection (adding wPP). Nevertheless, flexural strength and the elasticity modulus of polymer mortars decline by depending on the increment in content and sizes of the wastes used. That is highly connected to morphologies observed by SEM of the fractures polymer mortars. (C) 2020 Published by Elsevier Ltd.

Automated summary

The study investigated the impact of waste polypropylene and waste polyethylene on mechanical characteristics of polymer mortars, finding that adding waste can improve some mechanical properties, but also decrease flexural strength and elasticity modulus.