Evaluation of composites based on virgin rubber/devulcanized rubber reinforced with chemically and radiation activated polyurethane scrap for possible applications

Abstract

Reusing industrial waste is one of the new tactics being used to fight the dumping of solid waste for environmental protection. In the current work, the waste polyurethane (WPU) was ground to a fine powder and used for reinforcement of devulcanized waste rubber/styrene butadiene rubber (DWR/SBR) blends. DWR/SBR/WPU composites were prepared using (0, 3, 6, 9, 15, 30) phr (parts per hundred of rubber) of WPU. It was hypothesized that the treatment of WPU with trimethylolpropane triacrylate (TMPTMA) and irradiated at 10 kGy would improve its compatibility with the DWR/SBR blend and, consequently, its reinforcement efficacy. The incorporation of 30 phr of treated WPU (TWPU) improved the tensile strength (TS) by 47.7% and 8.6% compared to neat DWR/SBR and composites containing 30 phr of untreated WPU (UWPU). In addition, the incorporation of TWPU improved other mechanical characteristics such as tear strength, hardness, and abrasion resistance. As a result of increasing polarity and cross‐link density within the DWR/SBR blend after the addition of polar WPU, the resistance to motor oil was improved. The outcomes are encouraging from the standpoint of the circular economy and help produce high‐performing, reasonably priced DWR/SBR composites for a range of industrial uses, especially in the floor tiles application.Highlights Waste polyurethane (WPU) was activated using gamma irradiation in the presence of TMPTMA. The treatment of WPU improved its compatibility with DWR/SBR blend. The impact of WPU treatment on the properties of DWR/SBR blend was investigated. TWPU improved the mechanical properties of DWR/SBR blend more than UWPU. TWPU increased the motor oil resistance of DWR/SBR blend more than UWPU.