A process for producing polymer beads having ion exchange capacity and a porous polymeric matrix in which is distributed solid particulate material; the process comprising: (i) providing a dispersion having a dispersed organic phase and a continuous aqueous phase, the dispersed organic phase comprising: (a) polymerisable monomer composition, (b) solid particulate material, (c) non-polymeric porogen, (d) no polymeric porogen, and (e) dispersing agent for dispersing the solid particulate material throughout the dispersed organic phase, wherein the polymerisable monomer composition; (f) comprises at least one mono-ethylenically unsaturated monomer, (g) comprises at least one crosslinking monomer having at least two ethylenically unsaturated groups that are separated by at least 4 consecutive acyclic atoms; (h) comprises glycidyl methacrylate having a functional group; and (i) does not comprise divinyl benzene; (ii) polymerising the polymerisable monomer composition in the presence of the non-polymeric porogen and solid particulate material to form the porous polymeric matrix of the beads; and (iii) reacting the functional groups provided by the glycidyl methacrylate on the porous polymer matrix of the so formed polymer beads with a reactant compound chosen from monoamines, diamines, and polyamine compounds, and their respective salts to provide amine or quaternary ammonium groups. (i) providing a dispersion having a dispersed organic phase and a continuous aqueous phase, the dispersed organic phase comprising: (a) polymerisable monomer composition, (b) solid particulate material, (c) non-polymeric porogen, (d) no polymeric porogen, and (e) dispersing agent for dispersing the solid particulate material throughout the dispersed organic phase, wherein the polymerisable monomer composition; (f) comprises at least one mono-ethylenically unsaturated monomer, (g) comprises at least one crosslinking monomer having at least two ethylenically unsaturated groups that are separated by at least 4 consecutive acyclic atoms; (h) comprises glycidyl methacrylate having a functional group; and (i) does not comprise divinyl benzene; (a) polymerisable monomer composition, (b) solid particulate material, (c) non-polymeric porogen, (d) no polymeric porogen, and (e) dispersing agent for dispersing the solid particulate material throughout the dispersed organic phase, wherein the polymerisable monomer composition; (f) comprises at least one mono-ethylenically unsaturated monomer, (g) comprises at least one crosslinking monomer having at least two ethylenically unsaturated groups that are separated by at least 4 consecutive acyclic atoms; (h) comprises glycidyl methacrylate having a functional group; and (i) does not comprise divinyl benzene; (ii) polymerising the polymerisable monomer composition in the presence of the non-polymeric porogen and solid particulate material to form the porous polymeric matrix of the beads; and (iii) reacting the functional groups provided by the glycidyl methacrylate on the porous polymer matrix of the so formed polymer beads with a reactant compound chosen from monoamines, diamines, and polyamine compounds, and their respective salts to provide amine or quaternary ammonium groups. <EOS>