A series of five AB block copolymers of poly(ethylene oxide) (PEO) and poly(methyl
methacrylate) (PMMA) has been synthesised by the coupling of mono-functional homopolymers by
an esterification reaction. In this series polymers all contain a PMMA component of number
average molecular weight 908 gmo1·1, as measured by end group analysis, and the PEO components
have number average molecular weights of 596, 689, 979,
2023 and 2884 gmol·1, as measured by proton nuclear magnetic resonance
Aqueous "solutions" of these copolymers have been prepared both by direct mixing and
via methanol, a solvent for both blocks of the copolymer. Cloud points for these
copolymers have been determined and range from 275K to 368K for the lowest and
highest PEO blocks respectively. Small angle X-ray scattering (SAXS) of aqueous solutions has
been interpreted in terms of a core - shell model and dimensions determined for both.
Radii of gyration for the micellar cores have been shown to vary very little with
variations in copolymer composition, concentration and temperature up to the cloud point.
Fringe thicknesses show a dependence on PEO block length and relating measured fringe
thicknesses to calculated chain conformations indicates that the the chain conformation is best
described as an unperturbed chain. The measured fringe thickness is not altered by
concentration or temperature up to the cloud point. Above the cloud point it is not possible to
interpret the SAXS data in terms of a core shell micellar model. Significant differences in the
SAXS data have been observed depending upon the mode of addition of copolymer to water. This
can be interpreted as differences in micellar
With the exception of the lowest molecular weight copolymer all of the copolymers could be used as
steric stabilisers for the aqueous emulsion polymerisation of methyl methacrylate. Polymerisations
were only successful if the copolymer was introduced to the aqueous phase either via methanol or
via the monomer. Direct addition of copolymer to water resulted in low polymerisation
rates and unstable/flocculated products. Emulsions produced have been shown to be stable at pH
levels where the electrophoretic mobility was zero, ie. the emulsions were sterically
stabilised with no contribution from ionic I dipole interactions.
A Doctoral Thesis. Submitted in partial fulfilment of the requirements for the award of Doctor of Philosophy of Loughborough University.