RESEARCH ON THE SYNTHESIS OF COMPOSITE MATERIALS BASED ON RECYCLED POLYETHYLENE TEREPHTHALATE (PET) PLASTIC AND USED COFFEE GROUND

Abstract

In this study, we focused on utilizing two main types of food industry waste: spent coffee grounds (SCG) and post-consumer PET bottles (PETbot), to create
polymer bio-composite materials. Firstly, the post-consumer SCG was collected and treated using a chemical method, employing Ca(OH)2 solution with different
concentrations (0.5M, 1.0M, 1.5M) at various temperatures. This process aimed to clean and soften the SCG to facilitate the recycling process. Subsequently, we
fabricated composite materials based on PET reinforced with SCG, with a mass ratio of PET/SCG = 70/30 (by weight). The composite samples were then evaluated
for their mechanical properties, morphological structure, and thermal stability through appropriate experimental methods. The results of the study indicated
that spent coffee grounds treated with Ca(OH)2 solution at a concentration of 1.0M yielded the best outcomes. The established results showed the best
mechanical strength of the PET-based composite material reinforced with SCG when treated with Ca(OH)2 solution at a concentration of 1M, with tensile
strength: 82.86MPa; flexural strength: 160.29MPa; compressive strength: 81.34MPa; and Izod impact strength: 75.92kJ/m2
. This contributes to affirming the
potential of composite materials based on PET and SCG in practical applications.