Patent ID: 7847027

Claim:
A method of making core-shell polymer particles comprising the following steps: (a) forming a precursor polymer from a reaction mixture of monomers, including a monomer comprising a precursor group that can be converted to an amine or a quaternary ammonium group; (b) forming a linking-group-containing polymer by derivatizing a hydroxy-group-containing polymer comprising hydroxy groups on adjacent carbon atoms with a linking agent that is a compound comprising both an aldehyde moiety and an amine moiety, wherein one or more acetal moieties are formed in the linking-group-containing polymer, each acetal formed by the reaction of the aldehyde moiety in the linking agent with two hydroxy groups in the linking-group-containing polymer, wherein the amine moiety then becomes a linking group pendant from the linking-group-containing polymer, wherein the linking group is capable of reacting with the precursor group in the precursor polymer; and (c) reacting the amine moiety in the linking-group-containing polymer with the precursor group in the precursor polymer to form a higher order amine or quaternized ammonium moiety connecting the linking-group-containing polymer to the precursor polymer, thereby creating a core-shell particle which may optionally comprise unreacted precursor groups, wherein a first of said two polymers, either the precursor polymer or the linking-group-containing polymer, is a latex comprising a water insoluble polymer, wherein the latex forms a core for the core-shell particle and the second of said two polymers forms a shell.