Macromolecules · 1996 · 86 citations · 18 references
Natural SciencesMaterials EngineeringMaterials ScienceInterface SciencePolymer EngineeringPolymer MaterialsFracture ToughnessPolymer CharacterizationPolymer InterfacesPolymer Physical ChemistryPolymer PhysicsStrengthening MechanismsComposition-dependent Interaction ParametersCrack PropagationFracture MechanismsFracture Toughness Of PolymersInterfacial Fracture MechanicsInterfacial Fracture ToughnessToughened PolymersToughening Mechanisms
The strengthening of the interface between polystyrene (PS) and poly(methyl methacrylate) (PMMA) using a random copolymer P(S f - r -MMA 1 - f ), where f is the fraction of styrene in the copolymer, was investigated. The maximal fracture toughness, measured by crack propagation, was found when f = 0.68. Neutron reflectivity measurements showed that this value of f corresponded to the point where the interfacial broadening on the PS and PMMA sides of the interface was symmetric. The symmetry of broadening and the optimization of the toughness at f = 0.68 are attributable to a composition-dependent segmental interaction parameter.
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