The quasi-static tensile properties of PMMA (Elium 188) and Epoxy (Epopox A-28) resins are summarised in Table 1. Table 1. The average tensile properties of epoxy (Epopox A-28) and PMMA (Elium 188) resins Property Epoxy PMMA Young's modulus of elasticity (GPa) 2.3 (± ) 0.1 2.6 (± ) 0.1 Tensile failure strength (MPa) 53.7 (± ) 1.1 63.5 (± ) 0.3 Elongation at failure (%) 6.1 (± ) 0.4 6.6 (± ) 0.3 Summary of the materials: The epoxy was a standard resin (Epopox A-28, Amroy Europe, Lahti, Finland) polymerised by a polyether diamine hardener (Jeffamine D-23, Hunstman, Texas, USA) with a 35 wt% hardener to epoxy ratio. The resin was degassed before casting into an aluminium-made mould. The resin was cured following the manufacturer's instructions (i: at 90 °C for 24 h. ii: 150 °C for 2 h). The Epopox A-28 was used as an alternative for EPON 828 epoxy resin. The PMMA was in-situ polymerised at the ambient conditions by mixing a liquid methyl methacrylate thermoplastic resin (Elium 188, Arkema, Colombes, France) and dibenzoyl peroxide initiator (BP-50-FT1, United Initiators GmbH, Pullach, Germany) with 3 wt% initiators to resin ratio. The resin was degassed before casting into an aluminium-made mould. Summary of the tensile testing The quasi-static tensile tests were performed using a universal testing machine (model 5967, Instron, MA, USA). The testing was performed according to the ISO 527 testing standard. The dimensions of the dog-bone shape coupons were 4 mm (thickness) (× ) 10 mm (width) (× ) 170 mm (full-length). The gauge length was 50 mm. The specimen was prepared as 1A type in ISO 527. The tensile tests were performed by 30 kN load cell and 2 mm/min displacement rate. The displacement was recorded by a clip-on extensometer.

2022