A dispersion comprising (a) a continuous liquid phase and (b) a solid phase of epoxypolymer particles dispersed in the continuous liquid phase where the polymer is formed from monomers that are insoluble in the continuous phase a chemical agent is present within the polymer particles and the dispersion is not a Pickering dispersion and optionally the polymer molecules that form the polymer particles contain hydrophilic groups that hydrate on exposure to water in a manner that renders the particles permeable and that allows the chemical agent to diffuse out and optionally at least one non cross linkable mobile chemical such that the extraction of this chemical from the dispersed phase renders it porous in a manner that allows the chemical agent to diffuse out.
