| The polymerization of bicontinuous microemulsions has been shown to result in polymeric solids with a porous morphology. Due to the infancy of this technology, little has been done to explore potential applications. The objective of this study was to determine if polymerized microemulsions could be used as controlled release devices.; The investigation had several parts. Phase behavior studies were conducted in order to locate the bicontinuous region. Solutions counting the agent to be released and the polymer precursor were then polymerized. The resulting polymer monoliths were characterized by several techniques including scanning electron microscopy, freezing point depression, and thermogravimetric analysis. The swellability of the polymer in the release environment was also studied. Finally, the release profiles were determined by monitoring the UV absorbance spectra of the release medium. Release was found to be affected by factors associated with the microemulsion precursor system and factors associated with the release environment. The factors associated with the precursor composition studied were monomer ratio, crosslinker content, organic to aqueous ratio, and surfactant concentration in the aqueous phase. The factors associated with the release environment were temperature, ionic strength of the release medium, and the pH of the release medium.; The conclusions from this investigation are that polymerized microemulsions can be used for controlled release. The release profile was affected by the monomer ratio, crosslinker content, and organic to aqueous phase. These effects were due to the factors' influences on pore size, swellability, and phase separation during polymerization. The surfactant concentration had little effect. All of the release environment factors studied significantly affected release. For the systems studied, release was almost completely retarded at low release medium pH. |
