A method of preparing a macroporous cation exchange resin, the method comprising: forming an aqueous phase composition comprising a) a monomer mixture comprising i) a crosslinking monomer comprising N,N'-alkylenebis(meth)acrylamide, N,N'-heteroalkylenebis(meth)acrylamide, or a combination thereof in an amount of 15 - 90 weight percent based on the total weight of monomers in the monomer mixture; and ii) a negatively charged ionic monomer; and b) an aliphatic, water-soluble porogen having at least three hydroxy groups wherein the porogen is present in an amount up to 15 weight percent based on a total weight of monomers in the monomer mixture; and c) an aqueous phase solvent mixture comprising water and a mono-alcohol having 1 to 4 carbon atoms, wherein the mono-alcohol is present in an amount of at least 20 weight percent based on a total weight of the aqueous phase solvent mixture; suspending the aqueous phase composition in a non-polar organic solvent; polymerizing the monomer mixture to form particles of polymeric material; and removing the porogen from the particles to form a macroporous cation exchange resin having a capacity greater than 30 mg/mL for Immunoglobulin G. forming an aqueous phase composition comprising a) a monomer mixture comprising i) a crosslinking monomer comprising N,N'-alkylenebis(meth)acrylamide, N,N'-heteroalkylenebis(meth)acrylamide, or a combination thereof in an amount of 15 - 90 weight percent based on the total weight of monomers in the monomer mixture; and ii) a negatively charged ionic monomer; and b) an aliphatic, water-soluble porogen having at least three hydroxy groups wherein the porogen is present in an amount up to 15 weight percent based on a total weight of monomers in the monomer mixture; and c) an aqueous phase solvent mixture comprising water and a mono-alcohol having 1 to 4 carbon atoms, wherein the mono-alcohol is present in an amount of at least 20 weight percent based on a total weight of the aqueous phase solvent mixture; a) a monomer mixture comprising i) a crosslinking monomer comprising N,N'-alkylenebis(meth)acrylamide, N,N'-heteroalkylenebis(meth)acrylamide, or a combination thereof in an amount of 15 - 90 weight percent based on the total weight of monomers in the monomer mixture; and ii) a negatively charged ionic monomer; and i) a crosslinking monomer comprising N,N'-alkylenebis(meth)acrylamide, N,N'-heteroalkylenebis(meth)acrylamide, or a combination thereof in an amount of 15 - 90 weight percent based on the total weight of monomers in the monomer mixture; and ii) a negatively charged ionic monomer; and b) an aliphatic, water-soluble porogen having at least three hydroxy groups wherein the porogen is present in an amount up to 15 weight percent based on a total weight of monomers in the monomer mixture; and c) an aqueous phase solvent mixture comprising water and a mono-alcohol having 1 to 4 carbon atoms, wherein the mono-alcohol is present in an amount of at least 20 weight percent based on a total weight of the aqueous phase solvent mixture; suspending the aqueous phase composition in a non-polar organic solvent; polymerizing the monomer mixture to form particles of polymeric material; and removing the porogen from the particles to form a macroporous cation exchange resin having a capacity greater than 30 mg/mL for Immunoglobulin G.