Synthesis of Lamellar Mesostructures with Nonamphiphilic Mesogens as Templates

Abstract

Magnesium- and zinc-based lamellar mesostructures were synthesized with nonamphiphilic mesogens as templates. The templates used were disodium chromoglycate (DSCG) and flufenamic acid (FA) which are known to exhibit lyotropic liquid-crystalline phases in aqueous solutions. Evidence for the lamellar structure was obtained from the X-ray diffraction patterns and transmission electron micrographs. The interlayer spacings in the materials prepared with DSCG and FA, 30 and 24 Å, respectively, were large compared to the molecular dimensions of the templates, suggesting the existence of a bilayer arrangement of the templates between the inorganic walls. The presence of intact template molecules within the layers was confirmed by chemical analysis, TGA, IR, and NMR measurements. Interactions between the template molecules and the inorganic layer were evident through the increase in their decomposition temperatures as compared to the pure template and by the slight weakening of the CO bond as determined by the IR measurements. The synthesis of lamellar mesostructures with nonamphiphilic mesogens broadens the scope of the so-called “liquid-crystal template mechanism” in the sense that it is not limited to amphiphilic molecules but applies also to other molecules which can form large molecular assemblies in solutions.

Recent Advances in Synthesis and Applications of Transition Metal Containing Mesoporous Molecular Sieves

“…However, most of the mesoporous transition metal oxides synthesized to date, including Ti, [32] Nb, [24,25] Ta, [28] W, [23] Zn, [50] V, [51] Zr, [29±31] and Hf [33] are insulators containing high-valent transition metals in a single oxidation state. However, most of the mesoporous transition metal oxides synthesized to date, including Ti, [32] Nb, [24,25] Ta, [28] W, [23] Zn, [50] V, [51] Zr, [29±31] and Hf [33] are insulators containing high-valent transition metals in a single oxidation state.…”

Preparation of stable porous nickel and cobalt oxides using simple inorganic precursor, instead of alkoxides, by a sonochemical technique

“…Despite the above difficulties, mesostructured oxides were found possible for metals such as Sb, Fe, Zn, Pb, W, Sn, Mo, etc. [10][11][12][13][14][15][16]. However, most mesophases were layered and did not yield porous material when the surfactant was removed.…”

Change in Physico‐chemical Properties of PMMA and PS by Copolymerization with an Anionic Amphiphilic Comonomer: Sodium 11‐(methacryloyloxy) undecanylsulfate (MET)

“…Increase in temperature degradation with formation of lamellar structures has been reported elsewhere. [18] The enhancement of the thermal degradability could be due to the ability of MET monomer units to form clusters or lamellar structures. The existence of such structures in copolymers containing MET has been previously observed by TEM.…”