Nanostructured polymeric materials from microemulsion polymerization using poly(ethylene oxide) macromonomer

Transparent nanostructured polymeric materials have been produced from the direct polymerization of bicontinuous microemulsions using the macromonomer omega-methoxy-poly(ethylene oxide)(40)-undecyl-alpha-methacrylate (C-1-PEO-C-11-MA-40) as a polymerizable nonionic surfactant. Besides the PEO macromonomer, the system also consisted of methyl methacrylate (MMA), 2-hydroxyethyl methacrylate (HEMA), water, and the cross-linker ethylene glycol dimethacrylate (EGDMA). Most of the bicontinuous microemulsions investigated could be gelled within 10 min at 30 degrees C using a redox initiator. The transparent microemulsions were eventually transformed to transparent solid polymers. These polymeric materials were characterized by thermoporometry, SEM observation, and the pore size evaluation for the polymer films by PEG filtration. The pore size of these transparent polymeric materials ranges from about 1 to 10 nm in diameter. It was larger for the systems containing higher ratios of water to HEMA or water to C-1-PEO-C-11-MA-40 and smaller for higher ratios of HEMA to C-1-PEO-C-11-MA-40. The results from PEG filtration provide the direct evidence that bicontinuous nanostructured polymeric materials can readily be prepared via the polymerization of these nonionic bicontinuous microemulsions.