Self-peeling of gecko toes is mimicked by integration of film-terminated fibrillar adhesives to hybrid nematic liquid crystal network (LCN) cantilevers. A soft gripper is developed based on the gecko-inspired attachment/detachment mechanism. Performance of the fabricated gripper for transportation of thin delicate objects is evaluated by the optimum mechanical strength of the LCN and the maximum size of the adhesive patch.

Muscle-driven actuation of biomimetic microfibrillar structures is achieved using integrative soft-lithography on a backing splayed liquid-crystal elastomer (LCE). Variation in the backing LCE layer thickness yields different modes of thermal deformation from a pure bend to a twist-bend. Muscular motion and dynamic self-cleaning of gecko toe pads are mimicked via this mechanism.

We demonstrate the nanostructure and filament formation of a novel liquid crystal phase of a dimeric mesogen below the twist–bend nematic phase.

We present the first shear alignment studies and rheological measurements in the twist-bend nematic (N tb ) liquid crystal phase of odd numbered flexible dimer molecules. It is found that the N tb phase is strongly shear-thinning. At shear stresses below 1Pa the apparent viscosity of N tb is 1000 times larger than in the nematic phase. At stress above 10 Pa the N tb viscosity drops by two orders of magnitude and the material exhibits Newtonian fluid behavior. This is consistent with the heliconic axis becoming normal to the shear plane via shear-induced alignment. From measurements of the dynamic modulus we estimate the compression modulus of the pseudo-layers to be B~2kPa; this value is discussed within the context of a simple theoretical model based upon a coarse-grained elastic free energy.

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We have determined the nematic-isotropic transition temperature as a function of applied magnetic field in three different thermotropic liquid crystalline dimers. These molecules are comprised of two rigid calamitic moieties joined end to end by flexible spacers with odd numbers of methylene groups. They show an unprecedented magnetic field enhancement of nematic order in that the transition temperature is increased by up to 15K when subjected to 22T magnetic field. The increase is conjectured to be caused by a magnetic field-induced decrease of the average bend angle in the aliphatic spacers connecting the rigid mesogenic units of the dimers.Nematic liquid crystals (NLC) are anisotropic fluids that only exhibit uniaxial, apolar orientational order. In most liquid crystals, this order is temperature dependent, spontaneously arising at temperatures below the nematic-isotropic phase transition temperature (T NI );; above this temperature the material exhibits no order (i.e. is isotropic). In many nematics, orientational order is particularly responsive to external influences, for example electric and/or magnetic fields, mechanical strains, etc. [1-7].This response is the primary reason that nematic liquid crystals are extensively used in information display applications like liquid crystal displays (LCD's).

We present studies of chiral nematic liquid crystals composed of flexible dimer molecules subject to large dc magnetic fields between 0 and 31 T. We observe that these fields lead to selective reflection of light depending on temperature and magnetic field. The band of reflected wavelengths can be tuned from ultraviolet to beyond the IR-C band. A similar effect induced by electric fields has been presented previously, and was explained by a field-induced oblique-heliconical director deformation in accordance with early theoretical predictions. The use of magnetic field here instead of electric field allows precise measurements of some material constants and holds promise for wireless tuning of selective reflection.

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