Patent ID: 6841641

Claim:
A gradient copolymer comprising radically polymerizable low surface tension (meth)acrylate monomers and at least one other radically polymerizable ethylenically unsaturated monomer, wherein the radically polymerizable low surface tension (meth)acrylate monomers are selected from at least one low surface tension (meth)acrylate monomer represented by the general formulas: wherein R 1 is selected independently for each general formula from hydrogen, methyl and ethyl, R 2 is selected independently or each general formula from the group consisting of linear, branched, cyclic, aryl and arylalkyl fluorinated hydrocarbon groups containing from 4-20 carbon, a siloxane, a polysiloxane, an alkyl siloxane, an ethoxylated trimethylsilyl siloxane and a propoxylated trimethylsilyl siloxane; Y is a divalent linking group containing from 1 to 20 carbon atoms, m is an integer from 1 to 4, and R 3 is a C 1 -C 4 alkyl group, and wherein the copolymer has a polydispersity of less than 2.5, has a head end and a tail end, residues of the low surface tension (meth)acrylate monomers are positioned at the head end, residues of the at least one other radically polymerizable ethylenically unsaturated monomer are positioned at the tail end, and the proportion of low surface tension monomer residues to other monomer residues changes along the copolymer such that the concentration of low surface tension monomer residues decreases and the concentration of other monomer residues increases moving from the head end to the tail end of the copolymer.