Patent ID: 8551894

Claim:
An article comprising a porous thermoplastic substrate and extending from the surfaces thereof free-radically grafted biguanide ligand groups to form a free-radically-grafted substrate, wherein the free-radically grafted substrate is of the formula: Substrate˜(M ligand ) m , where Substrate represents the thermoplastic substrate, M ligand represents a polymerized grafted ethylenically unsaturated monomer having pendant biguanide ligand groups, and m is at least two; wherein said pendent biguanide ligands groups are selected from one or more of the formula: wherein R 2 is an arylene or alkylene and a is at least one and wherein the grafted ligand groups comprise the reaction product of a free-radically grafted electrophilic functional group and a ligand compound: wherein each R 4 is individually H, alkyl or aryl, each R 6 is individually alkylene or arylene, c may be zero or an integer from 1 to 500, and d is zero or 1, with the proviso that when d is zero, then c is 1 to 500.