Synthesis and characterization of hydrogels formed from glycidyl methacrylate (GMA) with anhydride derivatives

Abstract

The present investigation describes the synthesis and macromolecular reactions of maleic anhydride (MA)–acrylic acid (AA) and maleic anhydride (MA) - tert-butyl vinyl ether (t-VBE) binary reactive copolymers with glycidyl methacrylate (GMA) as a polyfunctional crosslinker. Copolymers with given composition of poly(maleic anhydride-alt-acrylic acid) (%47.17-%52.83) and poly(maleic anhydride-alt-tert-butyl vinyl ether) (% 45.18-%54.82) synthesized by radical binary copolymerization with benzoyl peroxide (BPO) and a,a’-azobisisobutyronitrile (AIBN) as initiator in p-dioxane and methyl ethyl ketone at 70oCin nitrogen atmosphere and initial monomer ratio 1:1, respectively. It is shown that the network structures are formed in copolymer/glycidyl methacrylate (GMA) in water and NaOH by intermolecular reaction between the anhydride units, as well as between hydroxyl fragment and free carboxyl groups of the acrylic acid and maleic anhydride unit, respectively. Swelling parameters such as beginning time of the hydrogel-formation, initial rate of the swelling, swelling rate constant, equilibrium swelling and equilibrium water content are determined copolymer/GMA/water system with various copolymer/crosslinker system. Formation of a hyperbranched network structure through the fragmentation of side–chain reactive groups in studied systems is confirmed by FTIR and DSC methods.