Here we report the use of unique organic − inorganic hybrid materials composed of octa-substituted polyhedral oligomeric silsesquioxane (POSS) cores as ionic liquid (IL) crystals. These materials have a wide temperature range in which they exist in liquid crystal (LC) phase because of the stabilizing effect of the POSS core. We synthesized ion pairs composed of alkyl chainsubstituted imidazolium and carboxylates of various lengths that were or were not connected to the POSS core; then the thermal properties of these materials were investigated. It was found that both ion salts and the octadecyl-substituted imidazolium ion pairs with or without connection to POSS could form LCs. Interestingly, the LC phase of the POSS-tethered ion salts was maintained until decomposition. In contrast, the octadecyl-substituted imidazolium ion salts that were not tethered to the POSS core showed a clearance point during heating. The highly symmetric structure of POSS contributes not only to the suppression of the molecular motion of the ion salts, but also results in the formation of regular structures, leading to thermally stable, thermotropic IL crystals. In addition, by using electrostatic interactions originating among ionic moieties, robust chiral structures can be produced. 3,4 Even a small quantity of chiral ionic sources can efficiently induce enantiomeric structures in a bulk sample, and ionic moieties can be assembled to form regularly ordered structures. 5,6 These well-ordered ionic moieties are expected to work as efficient cation carriers and scaffolds for ordering cations. These materials, which comprise closely assembled ionic species, can exhibit interesting optical and magnetic properties. Thus, new molecular designs for preparing thermally stable LCs composed of ionic species are needed to produce advanced functional materials.The concept of supported IL phases (SILPs) has been recently proposed. Several materials based on SILPs have exhibited important characteristics such as high ion conductivity and compatibility with organic reaction media; these materials have been used as templates for the formation of nanostructures. 1 Silica supports improve the thermal stability of LCs. 7,8 Carmichael et al. 9 have synthesized and explored silicon wafer-assisted SILP materials. They created layers with thicknesses between 10 and 21 nm of an ionic LC with [C 18 C 1 Im] [PF 6 ] on the planar wafer surface and found that the ionic LC formed a mesophase. Inspired by their work, Wasserscheid et al. 7 fabricated SILP materials using silicon nanoparticles and used them as supports for preparing mesoporous structures that could act as effective gasphase catalysts. 8 To construct advanced materials based on the concept of SILP materials, their properties must be fine-tuned according to preprogramed designs at the molecular level. A wide variety of

The structure and rheological properties of binary blends of polycarbonate (PC) and polystyrene (PS) were investigated using various PS samples with different molecular weights, namely PS1k (Mw = 1,000), PS53k (Mw = 53,000), and PS240k (Mw = 240,000). The blends with PS53k and PS240k show phase‐separated structures, whereas the blend with PS1k is miscible. The shear viscosity decreases greatly on addition of PS53k and PS240k, especially at high shear rates, which would be a great advantage at processing operations. Because the nonlinear response occurs in the small strain region for multilayered films of PC and PS240k, the origin of the significant viscosity drop for the phase‐separated system is interfacial slippage at the phase boundary.

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The effects of pressure and shear rate on the miscibility of binary blends comprising bisphenol-A polycarbonate (PC) and low molecular weight poly(methyl methacrylate) (PMMA) were investigated using a capillary rheometer. Both pressure and shear rate affected the miscibility. The examination of an extruded strand of the blend provided information about the cause of the phase change. Under high pressure, pressure-induced demixing occurred at temperatures below the lower critical solution temperature (LCST) of the blend. Consequently, the extruded strand became opaque throughout. During shear-induced mixing/demixing, a part of the strand became opaque because of the distribution of the shear rate in the strand. For example, during shear-induced demixing, only the exterior of the strand, i.e., the high shear rate region, became opaque. Above the LCST, shear-induced mixing occurred, and only the center region of the strand became opaque.