PHASE-BEHAVIOR AND MICROSTRUCTURE OF POLYMERIZABLE MICROEMULSIONS

The phase behavior of polymerizable alkyl methacrylates (C(k)MA, k = 1 , 4, and 6) in aqueous solutions containing mixtures of the cationic s urfactants dodecyltrimethylammonium bromide (DTAB) and didodecyldimeth ylammonium bromide (DDAB) is systematically studied. The added degree of freedom afforded by mixing the surfactants allows location of a reg ion in the water-rich corner of the phase diagram where a homogeneous microemulsion phase forms for three alkyl methacrylates of differing h ydrophobicity. Microstructural studies using small angle neutron scatt ering (SANS) demonstrate that oil-in-water microemulsions form and sho w that the shape of the aggregates depends on the DTAB:DDAB ratio and the oil content.