Abstract: A method of preparing a dispersion which includes the step of contacting a first phase, a first material immiscible therewith, a first polymeric material and a second polymeric material wherein: (a) (i) said first polymeric material has a repeat unit of the formula (I), wherein A and B are the same or different, are selected from optionally-substituted aromatic and thereoaromatic groups and at least one comprises a relatively polar atom or group and R1 and R2 independently comprise relatively non-polar atoms or groups; (ii) said first polymeric material is prepared or preparable by providing a compound of general formula (I), wherein A, B, R1 and R2 are as described above, in an aqueous solvent and causing the groups C?C in said compound to react with one another to form said first polymeric material; (b) said second polymeric material includes a functional group which is able to react with said first polymeric material so that covalent bonds are formed between said first and second polymeric materials; (c) t