The complete sets of elastic constants of 4H and 6H silicon carbide single crystals were determined by Brillouin scattering. The elastic constants of 6H SiC are C11=501±4, C33=553±4, C44=163±4, C12=111±5, and C13=52±9 GPa; the corresponding ones of 4H SiC are the same within experimental uncertainties. The compressibility, 4.5×10−3 GPa, is about 3–5 times smaller than those reported for polycrystalline SiC materials.

Stable square planar organocopper(III) complexes (CuNCC2, CuNCC4, and CuBN) supported by carbacorrole-based tetradentate macrocyclic ligands with NNNC coordination cores were synthesized, and their structures were elucidated by spectroscopic means including X-ray crystallographic analysis. On the basis of their distinct planar structures, X-ray absorption/photoelectron spectroscopic features, and temperature-independent diamagnetic nature, these organocopper complexes can be preferably considered as novel organocopper(III) species. The remarkable stability of the high-valent Cu(III) states of the complexes stems from the closed-shell electronic structure derived from the peculiar NNNC coordination of the corrole-modified frameworks, which contrasts with the redox-noninnocent radical nature of regular corrole copper(II) complexes with an NNNN core. The proposed structure was supported by DFT (B3LYP) calculations. Furthermore, a π-laminated dimer architecture linked through the inner carbons was obtained from the one-electron oxidation of CuNCC4. We envisage that the precise manipulation of the molecular orbital energies and redox profiles of these organometallic corrole complexes could eventually lead to the isolation of yet unexplored high-valent metal species and the development of their organometallic reactions.

Polyurethane elastomers (PUEs) containing trans-1,4-bis­(isocyanato­methyl)­cyclohexane (1,4-H6XDI) have been synthesized by polymerizing 1,4-H6XDI with poly­(oxytetra­methylene) glycol and 1,4-butanediol. The molecular aggregation state and mechanical properties of these PUEs have been compared with those exhibited by PUE analogues made of MDI and diols. The hard segment chains in the 1,4-H6XDI-based PUEs are found to readily crystallize and form strong hydrogen bonds due to a high symmetry of 1,4-H6XDI molecule. Consequently, the 1,4-H6XDI-based PUEs exhibit well-organized hard segment domains. This leads to their generally superior mechanical properties as compared to those of the well-known MDI-based PUEs. 1,4-H6XDI’s lack of aromatic moieties is expected to greatly enhance color stability of resulting PUEs. All the above features suggest 1,4-H6XDI could replace MDI in a range of applications.

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Changes in the microphase-separated structure of the poly­(styrene-b-ethylene-co-butylene-b-styrene) (SEBS) triblock copolymer (13 wt % polystyrene (PS) block) were investigated during mechanical deformation. In situ synchrotron radiation small-angle X-ray scattering (SAXS)/wide-angle X-ray scattering (WAXS) measurements were successfully performed for SEBS under equi-biaxial deformation as well as under uniaxial deformation. In situ SAXS/WAXS measurements revealed changes in (1) the shape of spherical PS domains, (2) the spacing of PS domains packed in the body-centered cubic structure in the initial state, (3) their ordering, and (4) the orientation of PEB chains during deformations. In terms of the microdomain structure, affine deformation was kept below a certain strain (εd‑A), which are 4 and 1.2 for uniaxial and equi-biaxial deformation, respectively. In contrast, the ordering of the arranged PS domains decreased from the initial strain region. Above the εd‑A value, deviation from affine deformation started to occur. This deviation is related to contact of PS domains under mechanical deformation. Uniaxial stretching still showed the plane-independent behavior, while equi-biaxial stretching did not. Moreover, the εd‑A value for equi-biaxial deformation was smaller than that for uniaxial deformation and further smaller than expected. This might be because the entanglement effect was enhanced for equi-biaxial deformation. Furthermore, after contact of PS domains at around strains of 6 and 2, during uniaxial and equi-biaxial deformation, respectively, the ordering of PS domains suddenly increased with an increase in strain. It is inferred that the locked state between the PS domains and the extended PEB chains formed during deformation may have been released and repacked at a certain strain.

Figure 7. a) IR absorbance on Au/ULDH−NiFe and ULDH−NiFe in the presence of H 2 O vapor at 50 °C and b) their difference. c) RAIRS−MES absorbance for Au/ULDH−NiFe under 0.1 MPa H 2 O vapor at 50 °C and d) the difference of RAIRS-MES signals observed on Au/ULDH−NiFe from those on ULDH−NiFe.

When isotropic solids are unequally stretched in two orthogonal directions, the true stress (force per actual cross-sectional area) in the larger strain direction is typically higher than that in the smaller one. We show that thiol-acrylate liquid crystal elastomers with polydomain texture exhibit an unusual tendency: The true stresses in the two directions are always identical and governed only by the area change in the loading plane, independently of the combination of imposed strains in the two directions. This feature proves a previously unidentified state of matter that can vary its shape freely with no extra mechanical energy like liquids when deformed in the plane. The theory and simulation that explain the unique behavior are also provided. The in-plane liquid-like behavior opens doors for manifold applications, including wrinkle-free membranes and adaptable materials.

Phosphorylated cellulose nanocrystal (P-CNC)/imogolite nanotube (natural aluminosilicate nanotube) hybrid thin films were fabricated by spin-assisted layer-by-layer assembly. Phosphorylation of CNC with diammonium hydrogen phosphate ((NH4)2HPO4) was carried out to introduce phosphate groups on the CNC surface for enhanced interaction with imogolite. Structure of the P-CNC/imogolite thin film was characterized by atomic force microscopy, scanning electron microscopy, X-ray diffraction (XRD), and grazing incidence wide-angle XRD. The film thickness increased linearly with the increment of the P-CNC/imogolite bilayer. Benefitting from the strong affinity between the phosphate group of the P-CNC and the Al–OH group of imogolite, the P-CNC/imogolite thin films were quite stable in water within a wide range of pH values, compared with the deterioration of the CNC/imogolite film under same soaking conditions.