Photoinitiated polymerization in bicontinuous microemulsions: Fluorescence monitoring

Abstract

The photopolymerization of bicontinuous microemulsions was simultaneously monitored with differential scanning calorimetry and fluorescence. The kinetics and mechanism of the reaction were studied throughout the entire photopolymerization reaction. The role played by the surfactant in the kinetics and morphology was studied. The nature of the surfactant changed the autoacceleration process and final conversion. The behavior was explained as a result of the differences in the interfacial properties. Anionic cetyltrimethylammonium bromide (CTAB) gave rise to a more flexible interfacial film than anionic sodium dodecyl sulfate (SDS), resulting in competition between the intramolecular and intermolecular reactions in the former systems. As cyclization did not contribute to the increase in the degree of crosslinking, SDS photopolymerization gave solids with a more rigid microstructure. Fluorescence methodology was applied to monitor bicontinuous microemulsion polymerization and to reveal the microstructure and morphology development during photopolymerization. The microemulsion composition was designed to prepare nanoporous, crosslinked materials. Even though the nanostructure of the precursor microemulsions was not retained because of phase separation during polymerization, mesoporous solids were obtained. Their morphologies depended on the nature of the surfactant, and membranes with open cells were successfully prepared with CTAB, whereas more complex morphologies resulted with SDS. V V C 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: [5291][5292][5293][5294][5295][5296][5297][5298][5299][5300][5301][5302][5303] 2006

Stand-Alone Semi-Solid-State Electrochemical Systems Based on Bicontinuous Microemulsion Gel Films

“…BME thick gel sheets (approximately 1 mm-thick) were prepared by photopolymerization 20 of acrylamide and a crosslinker. After irradiation, the transparent solution turned into a cloudy gel owing to the increase in the thickness of the microaqueous and oil phases based on spinodal decomposition.…”

Role of Surfactant during Microemulsion Photopolymerization for the Creation of Three-Dimensional Liquid Crystal Elastomer Microsphere Spatial Cell Scaffolds

“…All components (monomer, crosslinker, and photoinitiator) used for this report are commercially available and were prepared in an oil-in-water (toluene-in-H2O) microemulsion using several surfactants including CTAB for comparison (Peinado et al, 2006), following a photopolymerization procedure reported earlier (Bera et al, 2015). Reactive mesogens are confined within organic droplets, and the photopolymerization reaction arrests the building blocks in the final globular structure (see Figure 1).…”

Photopolymerization in dispersed systems

“…Polymerization of bicontinuous microemulsions enables preparation of microporous materials (pore diameter 1 -4 nm), as reported by using photoinitiation [150,151]. Photopolymerization of bicontinuous microemulsions of monoacrylates and diacrylates has also been studied by Peinado et al using fluorescent probes [152] As is usually the case, photopolymerization led to changes in the monomer microemulsion structure. The nanostructure of the initial microemulsion was not retained because of the fluid template resulting in phase separation, but mesoporous materials were achieved.…”