Multicolor Electrochromic Dye-Doped Liquid Crystal Yolk-Shell Microcapsules.

A new system of yolk-shell microcapsules containing two types of dye-doped liquid crystals was prepared via seed emulsion polymerization in which the synthetic process was mimicking plant respiration. The resulting system demonstrated reversible low voltage-driven switching between multispectral colored and transparent states. Moreover, wearable multicolor electrochromic fibers based on calcium alginate were produced via wet spinning to expand the application of yolk-shell dye-doped liquid crystal microcapsules.

Responsive Liquid-Crystal-Clad Fibers for Advanced Textiles and Wearable Sensors.

A simple process to clad conventional monofilament fibers with low-molecular-weight liquid crystals (LCs) stabilized by an outer polymer sheath is demonstrated. The fibers retain the responsive properties of the LCs but in a highly flexible/drapable format. The monofilament core makes these fibers much more rugged with a magnified response to external stimuli when compared to previously reported LC-core fibers produced by electrospinning or airbrushing.

Morphology Tuning of Electrospun Liquid Crystal/Polymer Fibers.

This paper elucidates the means to control precisely the morphology of electrospun liquid crystal/polymer fibers formed by phase separation. The relative humidity, solution parameters (concentration, solvent), and the process parameter (feed rate) were varied systematically. We show that the morphology of the phase-separated liquid crystal can be continuously tuned from capsules to uniform fibers with systematic formation of beads-on-a-string structured fibers in the intermediate ranges.

Airbrush Formation of Liquid Crystal/Polymer Fibers.

A homogeneous solution of a low-molecular-weight liquid crystal and a polymer spontaneously phase separates during airbrushing to form uniform fibers with a fluid liquid-crystal core surrounded by a solid polymer sheath. This structure forms because it effectively minimizes the interfacial energy of the phase-separated components while minimizing the elastic energy of the liquid-crystal core. These fibers incorporate the sensitive stimuli response of liquid crystals while maintaining the structural integrity, flexibility, and large surface-area-to-volume ratios inherent in fibers.

Orientational coupling amplification in ferroelectric nematic colloids.

We investigated the physical properties of low concentration ferroelectric nematic colloids, using calorimetry, optical methods, infrared spectroscopy, and capacitance studies. The resulting homogeneous colloids possess a significantly amplified nematic orientational coupling. We find that the nematic orientation coupling increases by approximately 10% for particle concentrations of 0.

Stressed liquid-crystal optical phased array for fast tip-tilt wavefront correction.

A liquid-crystal optical phased-array technology that uses stressed liquid crystals provides a new type of tip-tilt wavefront corrector. It demonstrates a very fast time response (10 kHz) and high beam-steering efficiency (approximately 91%). The new technology presented here will allow for a nonmechanical, high-speed correction with simple device construction.

Drag on particles in a nematic suspension by a moving nematic-isotropic interface.

We report a clear demonstration of drag on colloidal particles by a moving nematic-isotropic interface. The balance of forces explains our observation of periodic, striplike structures that are produced by the movement of these particles.