Abstract:
The study reported in this thesis concerns the relationship
between morphology and the properties of multicomponent
epoxy and methacrylate resins.
The thermodynamic and kinetic aspects of phase separation in
reactive, thermosetting, systems are explored and applied to
the investigation of blends of 'high performance' epoxy
resins with polyethersulphone. The mechanical properties of
the same cured blends are shown to be insensitive to
considerable variations in composition, cure and the
resulting morphology, both in the bulk-resin and in carbon
fibre-epoxy laminate forms.
Room temperature fracture and yield behaviour of highly
cross linked and rubber modified methacrylates, of rubber
modified dysfunctional epoxies, as well as of the above
mentioned epoxy/polyether sulphone blends, is investigated.
Special emphasis is placed on a comparison of the kinetics
of tensile creep between the different systems. Loss of
ductility in the highly cross linked resins is shown to
result in a very limited scope for toughness enhancement by
the usual rubber toughening methods.
