Novel polyion complex with interpenetrating polymer network of poly(acrylic acid) and partially protected poly(vinylamine) using N-vinylacetamide and N-vinylformamide

Abstract

Abstract Poly(vinylamine), the simplest polycation with primary amines, was applied to interpenetrating polymer networks (IPN) with poly(acrylic acid). N -Vinylformamide (NVF) was employed for amino-protected monomers to control electrostatic balance. pH-responsivities of IPNs varied, depending on the hydrolysis conditions and acrylic acid (AAc) concentration of the second network. Poly( N -vinylacetamide)- co -poly( N -vinylformamide) (4/6, mol/mol) was employed for the first network, subsequently hydrolyzed with 50% amide groups, and the second network was polymerized with 0.25 mol L −1 AAc, extremely shrunken hydrogels with polyion complex were formed at pH 7, showing that the controlled amount of highly active primary amines are available in IPN.