in 1962. After spending nearly 25 years at the Eastman Kodak Research Laboratories, he joined the Department of Chemistry Faculty at the University of Arizona in early 1987. His research interests include polymerization of organized media for the triggered release of reagents and the preparation of novel materials.

Block copolymers and amphiphile/water systems both exhibit very rich polymorphism. The bicontinuous cubic morphologies mediate the transformation from a lamellar phase to a hexagonallypacked cylinder phase. However, certain bicontinuous cubic morphologies can theoretically transform smoothly (without disruption or tearing) to other bicontinuous cubic morphologies in response to variation in temperature and concentration. These bicontinuous phases are best understood in terms of their associated minimal surfaces. The minimal surfaces D (i.e, ordered bicontinuous double diamond OBDD for block copolymer; cubic phase Q224 for amphiphile/water system), G (i.e., gyroid G* for block copolymer; cubic phase Q230 for amphiphile/water system), and P (cubic phase Q229 for amphiphile/water system; not yet reported for block copolymers) were computed and their two-dimensional projections on the plane reveals various 4-fold and 3-fold symmetries that are at times indistinguishable from that of the hexagonal phase. Moreover, because the surfaces are homotopic, certain 2-D projections of the three bicontinuous cubic phases are remarkably similar. However, the identification of bicontinuous cubic morphologies from each other by various microscopy techniques could still be achieved provided that the number of domains present in an experimental sample is large enough. Experimentally-obtained electron tomographs of sections of suspected bicontinuous phases may be compared with relative ease to the computed slices. These methods extend the range of concentrations in which bicontinuous cubic phases may be classified without the use of X-ray or neutron diffraction since diffractograms are generally difficult to obtain for the dilute samples commonly employed in amphiphile/water systems.

Technological applications of lipids may be possible through stabilization of various liquid-crystalline phases. One important approach to stabilized self-assembling materials utilizes polymerization of liquid-crystalline phases composed of reactive lipids. Polymerization of lipids has been utilized to modify the chemical and physical properties of lamellar assemblies (e.g., lipid monolayers, multilayers, and bilayer vesicles). In addition, polymerization of the lipid region of three-dimensional nonlamellar lipid-phase structures has recently been reported, including the reversed bicontinuous cubic (QII) phase, belonging to the space group Pn3m and the reversed hexagonal (HII) phase. Here we show that an easily prepared polymerizable monoacylglycerol combined in a 9/1 molar ratio with the corresponding polymerizable 1,2-diacylglycerol forms nonlamellar phases upon hydration at room temperature. Phase investigation using cross-polarized light, 2H NMR spectroscopy, and X-ray diffraction showed that the lipid mixture formed a well-defined cubic phase from at least 5 to 45 °C. The X-ray diffraction pattern corresponded to a cubic phase with Ia3d symmetry and a unit cell size of 131 Å at 25 °C. Polymerization to high conversion of this cubic phase was accomplished via the thermal decomposition of H2O2. The resultant polymers dissolved in organic solvent, indicating they were not cross-linked. The visual clear character, cross-polarized light test, and X-ray diffraction showed that isotropic architecture was maintained up to at least 70 °C after sample polymerization. The diffusion coefficient of water (23 °C) within the polymerized cubic phase, determined by pulsed field gradient NMR spectroscopy, was 1.2 ± 0.2 × 10-10 m2/s, a value consistent with retention of the cubic phase during and after the polymerization. The biocompatible and mesoporous nature of the polymerized cubic phase suggests it could be used as the host for incorporation of synthetic or biological molecules in a manner that has already proven especially useful in microporous solids.

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