Effect of reinforcements and crosslink density on Poly (methyl methacrylate) based nano-rubbers: friction, toughness and impact resistance

Building lighter but stronger has been a major industrial concern in recent decades. To achieve its goals, Altuglas International, a subsidiary of the Arkema group, has developed several types of nanostructured acrylic glass materials, that are lighter and more resistant than glass PMMA. Combining PMMA (polymethyl methacrylate) and a nanostructured elastomer, this material has perfect transparency and special mechanical properties. In addition to its automotive applications, its exceptional properties open up prospects in aeronautics and safety glazing. In the present study, different type of nanostructured PMMA, with different crosslink density has been studied and compared to standard PMMA, shock PMMA and polycarbonate (PC). Various mechanical tests, including, scratch-based friction tests (to assess the fracture and friction properties), indentation tests (to obtain elasto-plastic behavior and the creep response), fracture toughness assessment tests and dynamic mechanical analyses, have been performed. Furthermore, perforation tests, were carried out using pneumatic gas gun having different impact velocities varying from 8 to 161 m/s. The obtained results show the combined effect of both rubber bloc nanostructuration and crosslink density. It’s was observed that the addition of rubber at nanometer scale leads to improvement of mechanical properties such as toughness, friction and impact resistance. Moreover, when moderately increasing the crosslink density, several physical properties, including glass transition temperature, toughness, friction, hardness and ballistic limit were significantly improved.