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Aqueous lyotropic liquid crystal (LLC) assemblies with bicontinuous cubic morphologies (Q-phases) have shown promise in applications ranging from selective chemical separations to ion transporting media, yet universal design criteria for amphiphiles that adopt these unique structures remain elusive. Recent reports have demonstrated that cationic gemini surfactants exhibit a tendency to form bicontinuous cubic LLCs as compared to single-tail amphiphiles; however, the universality of this surfactant design motif in stabilizing Q-phases remains untested. Herein, we report the modular synthesis of a new class of anionic gemini surfactants derived from aliphatic carboxylic acids and demonstrate their unexpectedly strong propensity to form gyroid LLC phases with unprecedented stability between 25 and 100 °C over amphiphile concentration windows up to 20 wt % wide. By systematically varying the alkyl spacer length and surfactant counterions (Na+, K+, and (CH3)4N+), we identify molecular motifs that favor formation of technologically useful bicontinuous cubic LLC morphologies. [ABSTRACT FROM AUTHOR]

Cobalt-mediated radical polymerizations (CMRPs) utilizing redox initiation are demonstrated to produce poly(vinyl ester) homopolymers derived from vinyl pivalate (VPv) and vinyl benzoate (VBz), and their block copolymers with vinyl acetate (VAc). Combining anhydrous Co(acac)2, lauroyl peroxide, citric acid trisodium salt, and VPv at 30 °C results in controlled polymerizations that yield homopolymers with Mn = 2.5-27 kg/mol with Mw/ Mn = 1.20-1.30. Homopolymerizations of scrupulously purified VBz proceed with lower levels of control as evidenced by broader polydispersities over a range of molecular weights ( Mn = 4-16 kg/mol; Mw/ Mn = 1.34-1.65), which may be interpreted in terms of the decreased nucleophilicity of these less electron donating propagating polymer chain ends. Based on these results, we demonstrate that sequential CMRP reactions present a viable route to microphase separated poly(vinyl ester) block copolymers as shown by small-angle X-ray scattering analyses. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 [ABSTRACT FROM AUTHOR]