Effect of polyethylene glycol on rheological, thermo-mechanical, and tribological behavior of epoxy

Over the past few years, polyethylene glycol (PEG) has been recognized as an effective blend to enhance the mechanical properties of brittle epoxy. However, the literature contains limited systematic studies evaluating PEG's role in improving epoxy performance. Therefore, a systematic approach was employed in the present study to assess the impact of varying weight percentages of PEG on the viscosity, thermo-mechanical, and tribological properties of epoxy. Adding 10 wt% PEG (PEG-10) in epoxy is identified as the threshold limit. With PEG-10, the viscosity significantly decreased by approximately 78%, while fracture toughness, tensile strength, tensile modulus, and failure strain improved by 59.5%, 38.5%, 37.8%, and 54%, respectively, compared to neat epoxy. Additionally, the wear rate was significantly reduced by 92% compared to neat epoxy, though thermo-mechanical and flexural properties were slightly compromised. Furthermore, the failure mechanisms of the tensile fracture surfaces and wear tracks of epoxy-PEG blends were examined to understand PEG's role more comprehensively.Highlights A Significant drop in the viscosity of epoxy resin is achieved with the help of PEG-400. PEG-400 is mixed with epoxy resin to improve its fracture toughness and tensile properties. A 92% reduction is observed in the wear rate when PEG-400 is mixed with epoxy resin at 10 wt%.