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A series of novel star-shaped ionic liquid crystals (ILCs) compounds with various counterions (derived from HBF4, HPF6, CF3COOH, d-MH-SO3H, H3PO4, p-Toluenesulfonic acid) were designed and synthesised starting from precursors of pyridines and liquid crystalline monomer cholesteryl 4-bromobutanoate. Inducing various counterions by use of ionic self-assembly due to electrostatic attraction of various ion clusters was one of the most essential factors for intermolecular separation. The chemical structures, liquid crystalline properties, self-assembly behaviour and ionic conductivity of these compounds were researched during multiple experimental techniques. The star-shaped ILCs showed a smectic A (SmA) mesophase. The d-spacing of star-shaped ILCs increased slightly due to the increase volume of anion. The clearing temperatures of the pyridinium salts suggested that the effect of the stabilisation on the SmA structures was in the order H2PO4−>BF4−>TS−>D-MH-SO3−>CF3COO−>PF6−. All these star-shaped ILCs displayed ionic conductivity in mesophase. It was noted that the conductivity (σ) increased with the increase of the anion size and temperature. [ABSTRACT FROM AUTHOR]

Series of novel star-shaped liquid crystals containing [1,1ʹ-biphenyl]-4,4ʹ-diyl diisonicotinate mesogens with various counterions (Br−, B-SO3−,C-SO3−,H2PO4−, BF4−) have been synthesized and characterized, which display a nematic phase. The molecular structures of the liquid crystals, thereof consisting of rod-like mesogens linked together by different long alkyl spacers to a small disc-like core of central benzene-1,3,5-triyl triisonicotinate, have been fully characterized by 1H NMR. Their thermal and supramolecular organization behaviours have been studied by combining polarized optical microscopy, differential scanning calorimetry and small-angle X-ray scattering. These investigations showed that the mesophase temperature range increased with increasing alkyl chain length and the clearing point decreased with increase of anion size. These star-shaped liquid crystals have a long and ordered molecular structure, the electron delocalization of the π-π stacking conjugation effect and the electrostatic attraction of ionic make them have good ferroelectric properties and ionic conductivity properties. The interest in preparing ionic liquid crystal with a nematic phase lies in the technological applications as it is well known that the nematic phase has the highest fluidity of all liquid crystalline phases and hence the possibility to align it by applying an external electric/magnetic field, commonly used in electro-optical devices. [ABSTRACT FROM AUTHOR]

A series of quaternary phosphonium salts based on ionic liquid-crystalline polymers which were synthesised by triphenylphosphine and brominated polysiloxanes containing cholesteryl mesogens. The chemical structures, liquid crystalline properties and antimicrobial performance of [ChP]Brs were investigated by a series of test methods. [ChP]Brs showed smectic A mesophase with a wide temperature range of liquid crystalline phase in the heating and cooling cycles. The glass transition temperature and clearing point temperature decreased with the increase of triphenylphosphine content. While the increase of phosphorus content lead to the increase of antibacterial properties of polymers. The liquid crystal polymer provides full spatial support for complete contact between phosphorus ions and bacteria, So that the quaternary phosphonium salt can be fully sterilised. [ABSTRACT FROM AUTHOR]

Self‐assembly of mesogens in one polymer system reflects the capability for integrating intermolecular interactions and functions of materials. A series of novel supramolecular complexes (SCPs) containing cholesterol derivatives, siloxane backbone and copper phthalocyanine were synthesized. The SCPs were made from sulfonic acid‐containing precursor polymers (SAPs) synthesized by the use of 4‐(allyloxy)benzenesulfonic acid, cholest‐5‐en‐3‐ol‐(3β)‐4‐(allyloxy)benzoate and polymethylhydrosiloxane. Differential scanning calorimetry, polarizing optical microscopy and X‐ray diffraction results confirmed the mesomorphic properties. The SAPs showed smectic phase, but the SCPs showed columnar phase due to more lateral copper phthalocyanine groups in the polymer systems. Moreover, because of rigid side groups and cholesteric polymer, SCPs showed greater d‐spacings between the side mesogenic groups and exhibited very good electrical conductivity. © 2018 Society of Chemical Industry Supramolecular complexes containing cholesterol derivatives, siloxane backbone and copper phthalocyanine were synthesized, whereby the liquid crystal phase changes from smA to Colh. The complexes exhibit good electrical conductivity. [ABSTRACT FROM AUTHOR]

Two‐dimensional (2D) nanosheets‐based membranes, which have controlled 2D nano‐confined channels, are highly desirable for molecular/ionic sieving and confined reactions. However, it is still difficult to develop an efficient method to prepare large‐area membranes with high stability, high orientation, and accurately adjustable interlayer spacing. Here, we present a strategy to produce metal ion cross‐linked membranes with precisely controlled 2D nano‐confined channels and high stability in different solutions using superspreading shear‐flow‐induced assembly strategy. For example, membranes based on graphene oxide (GO) exhibit interlayer spacing ranging from 8.0±0.1 Å to 10.3±0.2 Å, with a precision of down to 1 Å. At the same time, the value of the orientation order parameter (f) of GO membranes is up to 0.95 and GO membranes exhibit superb stability in different solutions. The strategy we present, which can be generalized to the preparation of 2D nano‐confined channels based on a variety of 2D materials, will expand the application scope and provide better performances of membranes. [ABSTRACT FROM AUTHOR]