Micromechanics of deformation in polymers modified by inorganic and rubber particles

Abstract

Many structural polymers exhibit brittle behavior at low temperatures and/or high strain rates. It has been shown that the incorporation of rubber and inorganic particles can have significant toughening effects. Previous studies have shown that the particles can alter the matrix morphology at the particle-polymer interface to provide the material with a low shear yield strength tangential to the particle interface thus promoting extensive plastic flow. Through finite element analysis, this thesis examines the micromechanisms of deformation for the toughened polymer blends. Particularly, how the nature of the particles and its bonding with the matrix affect the development of plastic deformation in the matrix material. Micromechanical models are constructed for the both the isotropic and anisotropic polymer matrix modified by rubber and inorganic particles. For the case of the inorganic particle, the two limiting bonding cases examined are the incoherent and the perfectly bonded particle.