Research on copolymer nanoparticles prepared from acrylamide-sodium acrylate inverse micro-emulsion system

Copolymer nanoparticles were prepared from kerosene/acrylamide-sodium acrylate/ Span80-Tween60 inverse micro-emulsion system.The structure of the prepared copolymer was studied with infrared spectroscopy(IR) and 13C nuclear magnetic resonance(13C NMR),the morphology of the copolymer was studied with transmission electron microscopy(TEM),and the molecular weight as well as molecular weight distribution of the copolymer were studied with gel permeation chromatography(GPC).Homogenous,stable and transparent micro-emulsion was obtained at 40 ℃ when the optimum HLB value required for emulsion stability was 9,the mass concentration of monomer was 40% relative to total mass of the water phase and the mass fraction of(NH4)2S2O8-NaHSO3,as initiator,was 0.7‰ relative to the total mass of monomer.The resultants were acrylamide-sodium acrylate copolymers,with viscosity-average molecular weight of 5×105 g/mol.The copolymer particles were uniformly distributed,as regular spherical shape with nanometer scale particle size.