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Abstract: Cyanobacteria are regarded as very eco‐friendly microreactors for the production of various biomolecules such as polysaccharides by fixing not only carbon but also nitrogen in water. Cyanobacterial polysaccharides having various functional groups such as hydroxyls, carboxyls, sulfates, etc. have the ability to interact with metals or inorganics, to create bionanocomposites. Sacran, a supergiant cyanobacterial anionic polysaccharide extracted from the extracellular matrix of Aphanothece sacrum which is mass‐cultivated in freshwater, is mainly used to create functional bionanocomposites. Gel‐type bionanocomposites of sacran with various metal cations are formed and showed photoresponsive functions. Metal recovery is performed from the sacran bionanocomposite gels. Sacran chains are complexed with multi‐wall carbon nanotubes (MWCNT) to give viscose dispersion from which MWCNT bionanocomposites can be collected by electrophoresis. The MWCNT/sacran dispersion retains the capability of adsorbing various metal ions to form hardened hydrogel beads. Finally, natural inorganic sepiolite can be used for sacran bionanocomposites which show an efficient neodymium ion adsorption ability. Thus, cyanobacterial polysaccharides are useful for preparing eco‐friendly and functional bionanocomposites with various hard materials. [ABSTRACT FROM AUTHOR]

Wetting phenomena play important roles in several technological applications and in many physical and biological thin-film phenomena, such as wetting, adhesion and friction. One of key issues of these studies is to control the surface energy (or wettability) dynamically for liquid transportation. We have developed a liquid crystal (LC) surface for use as a transport substrate since we expected that the surface energy of an LC surface can be controlled rapidly using an electric field. The rapid control of the polarisability (or wettability) of a liquid crystalline surface by an electric field has been demonstrated, together with the transportation of a liquid microdroplet. [ABSTRACT FROM AUTHOR]

[Display omitted] Generation of long-range ordering of colloidal particles through anisotropic interactions is of growing interest in material designing. At submicron-scale, routine works use synthetic spheres or rods but the knowledge pertaining to assembly of binary combination of particles is severely restricted. Improved understanding of the fundamental aspects that drive self-assembly, can lead to robust strategies for fabrication of topographically oriented films. The fluidical geometry of a liquid crystalline (LC) solution of polysaccharide consisting of micron-sized rod and platelet units was explored. The solutions, characterized for their rheological behavior, were evaporated from a rectangular cavity. The assembly and orientation of the units was monitored by polarizing microscopy and the interparticle capillary forces approximated mathematically. The units deposited into an uninterrupted membrane upon interfacial evaporation, forming a bridge along the 8 mm gap, linking the substrates. The membrane, composed of a lamellar structure, was uniaxially oriented along the direction of the gap. The rheological estimations corroborated an extremely high value of viscosity with the presence of crosslinking junctions in this solution when compared to a solution with only rod units, capable of bridging a maximum of 1 mm. It has been demonstrated for the very first time that the presence of platelet-units contributes lateral capillary interactions and assist rod-units towards a wider, self-assembled structure. [ABSTRACT FROM AUTHOR]

Uniaxial orientation is highly desirable for fabricating advanced soft materials. Liquid crystal (LC) polymer deposition was strategically manipulated at the air-LC interface, by controlling the drying temperature and initial concentration of aqueous solution of xanthan gum in a limited space. Interface-assisted orientation led to membrane-like depositions bridging the millimeter-scale gap between the substrates both, vertically and horizontally. The applicability of this approach lies in synchronization of the molecular orientation beyond their individual LC domains into the condensed state. Cross-polarized microscopy and SEM analysis correlated the orientation of the deposited polymer with the controlled mobility of xanthan gum LC domains at the evaporative interface. Subsequently, a phase diagram was prepared for the variety of oriented structures, depending upon the drying conditions. The deposited membrane behaved as an oriented hydrogel showing reversible anisotropic swelling/deswelling only along its thickness. [ABSTRACT FROM AUTHOR]

Poly(4-hydroxycinnamic acid) (P4HCA), poly(3-hydroxycinnamic acid) (P3HCA), poly(3-methoxy-4-hydroxycinnamic acid) (PMHCA) and poly(3,4-dihydroxycinnamic acid) (PDHCA) were synthesized by the thermal poly-condensation of the corresponding monomers, which are lignin precursors, coumaric acid derivatives consisting of cinnamoyl groups and different position and number of OH groups. The solubility of the homo-polymers in organic solvents decreased in the order of P3HCA > PDHCA > P4HCA > PMHCA. The wide angle X-ray diffraction (WAXD) results indicated that P4HCA or PMHCA with p-OH group had higher crystallinity, in contrast to P3HCA or PDHCA with m-OH group which had lower crystallinity. Crossed-polarizing microscopy suggested that P4HCA had the nematic liquid crystal properties at 220°C and PDHCA showed birefringence properties at 200°C. In cell-adhesion tests, PDHCA showed the highest cell adhesion (ca. 70%), whereas P3HCA, P4HCA and PMHCA had 50, 18 and 10% cell adhesion, respectively. The coumaric acid derivative homo-polymers can be useful as cell adhesion controllable thermotropic polymers for biomedical and environmental fields. [ABSTRACT FROM AUTHOR]