Investigation of mechanical properties and microstructural analysis of polymeric waste strengthened hybrid composites

Abstract

In this work, investigated the mechanical properties and microstructure of Ground Tyre Rubber (GTR) i.e. polymeric waste blended with Natural Rubber (NR), Butadiene Rubber (BR), and Styrene-Butadiene Rubber (SBR) composites. A two-roll mill and hydraulic press were used to create NR (70 parts per hundred of rubber (phr)) composites with 25 phr of BR and 5 phr of SBR and various proportions of GTR (0, 10, 20, 30, and 40 phr). With the incorporation of Nylon 6 (Ny 6) at 5 phr, the interfacial adhesion of NR/BR/SBR composites was improved. NR-based hybrid composites with mechanical and curing properties were enhanced and compared with pure NR. It was noted that the maximum tensile strength, tear strength, and hardness were enhanced by 77.74%, 17.9%, and 36.4% in NR/BR/SBR/GTR (70/25/5/40) over pure NR. The elongation at break was decreased by 54.55%, while young’s modulus was enhanced in NR/BR/SBR/GTR (70/25/5/40) over pure NR. With the incorporation of 40 phr of GTR in the NR/BR/SBR composites, cure properties like scorch time (t_S2) and cure time (t_C90) were reduced by 53.97% and 65.71%, while the minimum torque (M_L) and maximum torque (M_H) were enriched by 13.35% and 12%, respectively, when compared with the pure NR. Based on the Scanning Electron Microscope (SEM) and Thermogravimetric Analysis (TGA), GTR particles were uniformly distributed, and the thermal stability was enhanced by 25.40% in NR/BR/SBR/GTR (70/25/5/40) composites over pure NR. The absorption bands of NR, BR, SBR, and GTR elements in the developed hybrid composite were identified by Fourier transform infrared. The glass transition temperature (T_g) was diminished from -58.17°C to -63.42°C. With the inclusion of 40 phr of GTR in the NR/BR/SBR composite. Finally, it was recommended that the incorporation of 40 phr of GTR is suitable for NR/BR/SBR composites.