Glassy polymers, such as polystyrene (PS), poly(methyl methacrylate) (PMMA) and polycarbonate (PC), are common engineering polymers that have found uses in consumer products ranging from portable computers and optical lenses, to automotive components and appliance housings. PMMA and PS are typically considered to be brittle polymers, since they fail in a brittle manner under low triaxiality conditions, such as under uniaxial tension. Polycarbonate is considered to be a more ductile polymer than PMMA and PS, since it will deform plastically under uniaxial tension. However, PC does exhibit brittle behavior under certain loading conditions, such as low temperatures, high strain rates, or highly (tensile) triaxial stress states. A technique used for reducing the brittleness (increasing the fracture toughness) of glassy polymers is rubber-toughening. The technology of rubber-toughening, which involves blending a small volume fraction (5-20%) of rubber particles with the homopolymer, has been used commercially since the 1940s, and has been of major importance to the plastics industry. The technology of rubber-toughening is qualitatively well understood, but quantitative tools to study the material response are still at an early stage of development. The purpose of this thesis is to develop numerical tools to investigate the mechanical behavior of rubber-toughened glassy polymers, with emphasis on rubber-toughened PC. To this end, several tools are developed.
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