Study of the influence of accelerated aging on the physical and mechanical properties of polymer composites containing rubber, polyethylene and poly(ethylene terephthalate) waste

Abstract

Polymer composites have been used in civil engineering for years, but the need to follow current trends, and thus the need to modify these materials, requires systematic monitoring of their durability. The article describes the results of research on concrete-like resin composites, the main ingredients of which are: synthetic resin, hardener and aggregate. This material (control mortar (c)) was modified in two ways: within the epoxy resin matrix and/or sand aggregate, with such recycled materials as: poly(ethylene terephthalate) (PET) from bottles (resin substitute in the amount of 9% by mass), polyethylene (PE) from plastic bags or rubber from car tires (R) - aggregate substitutes in the amount of 10% by volume. Experimental tests of mortar samples subjected to accelerated aging processes in a chamber simulating irradiation and rain cycles allowed the analysis of the physico-mechanical properties of composites depending on the degree of exposure to solar radiation and moisture. The results of the accelerated aging studies were used to compare the relative behavior of composites with different compositions. For this purpose, analyses based on scanning electron microscopy were also performed. Both the type of waste and the aging time significantly differentiate the strength parameters of mortars. MPa. All samples clearly changed color, but even after 2000 h of accelerated aging, the flexural strength exceeds 30 MPa and the compressive strength exceeds 110 MPa, while the control samples matured in laboratory conditions had a flexural strength of 18 MPa and a compressive strength of 74.3 MPa. The cost-economic analysis confirmed that incorporating waste into composites is beneficial, even if they are exposed to aging factors.