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Lyotropic liquid crystals (LLCs) have recently been employed as polymerization templates to yield highly ordered nanostructured hydrogels, which have shown promise in biological separations and tissue engineering. To allow greater control of hydrogel structure using LLC templates, this study focuses on the influence of polymerization kinetics and temperature on ultimate polymer morphology and properties. A more in-depth understanding of these phenomena has been obtained through extensive examination of polymer structure with small-angle X-ray scattering (SAXS) and scanning electron microscopy (SEM). The impact of different polymerization rate and temperature regimes on polymer morphology was determined using isotropic, cubic, and hexagonal phases as polymerization templates. Polymer morphology varies dramatically depending on LLC phase template, while within a given phase changes in polymerization time scale and temperature greatly impact polymer structure. SAXS reveals a higher degree of retained liquid crystalline order using rapid polymerization at relatively low temperatures. SEM images demonstrate that rapid polymerization yields polymers with highly ordered network structures and nanoscale morphology. Less ordered, thermodynamically driven polymer features result from relatively slow polymerization. The degree of swelling in aqueous solution increases dramatically in ordered LLC phases relative to bulk polymerization, with lower swelling resulting from faster polymerization. Similarly, higher surface area results from polymerization in LLC media relative to isotropic systems, and surface area increases with increasing polymerization rate.

This article presents information about the process of creating an asynchronous learning experience for postsecondary school students employing a hybrid World Wide Web and CD-ROM technology. The steps include assembling an appropriate studio facility, identifying content experts and training them in the use of pre- and postproduction hardware and software, and designing the product to be user (student) friendly and attractive. Examples are included, and the advantages and disadvantages of types of software and hardware are discussed.

The article announces various appointments including appointment of Ben Fowke as a chief operating officer at Xcel Energy Inc., Scott Schneider as a regional president of North America at Otto Bock HealthCare LP and Matthew Rocco as executive vice president at Grandbridge Real Estate Capital LLC.