Poly(acrylamide-<i>co</i>-styrene): A Macrosurfactant for Oil/Water Emulsion Templating toward Robust Macroporous Hydrogels
Emina Muratspahić, Jana Schöffmann, Qixiang Jiang, Alexander Bismarck
Abstract
High Resolution Image Download MS PowerPoint Slide Large amounts of relatively expensive small-molecule surfactants, between 6 and 25%, are typically required for the formulation of oil/water high or medium internal phase emulsion (H/MIPE) templates. We synthesized an amphiphilic “macrosurfactant” copolymer poly(acrylamide- co -styrene) via micellar polymerization. As-synthesized poly(acrylamide- co -styrene) still associated with 0.01 wt % cetyltrimethylammonium bromide (CTAB) can be used to produce stable toluene or cyclohexane-in-water H/MIPEs already at concentrations of 0.1 wt %. Emulsion templates containing 2-hydroxyethyl methacrylate (HEMA) and N, N -methylenebis(acrylamide) (MBAm) in the aqueous continuous phase can be polymerized to produce macroporous poly(HEMA- co -MBAm)M/HIPEs. Our poly(HEMA- co -MBAm)M/HIPEs synthesized in templates stabilized with much lower emulsifier content were mechanically more robust, in dry and swollen state, as compared with poly(HEMA- co -MBAm)HIPEs reported in the literature.