Plasma-enhanced functionalization of substrate surfaces with quaternary ammonium and quaternary phosphonium groups

Abstract

Bactericidal substrates and methods of functionalizing the surface of substrates with quaternary ammonium and quaternary phosphonium groups using non-equilibrium RF plasmas are provided. The methods include the step of treating the surface of a substrate with a plasma to create surface active sites. Some methods include the step of reacting the surface active sites with linker molecules, which are then reacted with quaternary ammonium precursor molecules to provide a substrate surface functionalized with quaternary ammonium precursor groups. Other methods react the surface active sites with polymer precursor molecules under plasma conditions to form a covalently-bound polymer layer having reactive sites. The polymer reactive sites are reacted with quaternary phosphonium precursor molecules to provide a substrate surface functionalized with quaternary phosphonium groups. Also provided are bactericidal substrates having immobilized, covalently-bound quaternary ammonium or quaternary phosphonium groups.