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A series of phthalocyanine‐based liquid‐crystalline poly(styrene sulfonic acid) compounds (LCPCs) are synthesized using cholesterol, dicarboxylic acid, amino‐ zinc phthalocyanine, and polystyrene sulfonic acid. The chemical structure, thermal property, liquid‐crystalline behavior, direct current conductivity, and temperature‐controlled molecular electronic switch property are investigated by use of various techniques. The LCPCs show both columnar phase (Colh) induced by the phthalocyanine moieties and nematic discotic (Nd) phase formed by the collapse of the columnar phase structure. The temperature‐dependent conductivity of the LCPCs is associated with the activation energy evaluated by Broido's graphical procedure according to the thermogravimetric analytical curves. The LCPCs show low conductivity derived from 1D charge migration through phthalocyanine cores in the colh phase, but exhibit high conductivity due to 3D ionic charge transport in the Nd phase. A temperature‐controlled molecular electronic switch is fabricated on the basis of the temperature‐dependent conductivity property, which can be useful for some potential applications.

Magnetorheological (MR) fluids are a kind of smart materials whose yield stress increases considerably when they are applied an external magnetic field. The MR effect and sedimentation stability are two...

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A series of pyridinium‐based polymerized ionic liquid crystals (PILCs) with different anions were synthesized, including poly(pyridinium bromide)s and poly(pyridinium trifluoroacetate)s, and their chemical structure, liquid‐crystalline properties and conductivity properties were investigated by many experimental techniques. At low temperature, some PILCs containing less cholesteryl mesogens presented smectic A phases; while the PILCs containing more cholesteryl mesogens displayed bicontinuous cubic phases. At high temperature, all the PILCs showed nematic phases. Compared with the corresponding poly(pyridinium bromide)s based on identical polymer cations, the poly(pyridinium trifluoroacetate)s showed lower glass transition and isotropic transition temperature. The PILCs displayed excellent temperature‐dependent ionic conductivity, making it attractive for applications in temperature‐controlled electronic switches. In cubic and smectic A phases, the PILCs presented Arrhenius‐like ionic conductivity behavior, and they exhibited Vogel–Fulcher–Tammann‐like behavior in nematic phases.

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