Thermoresponsive liquid crystalline polymer membranes that undergo phase transition at body temperature

Body‐temperature shape‐shifting liquid crystal elastomers

“…3 Since the conception of the liquid crystal elastomers, various novel engineering applications have been proposed based on the reversible actuation including actuators, [4][5][6] soft robotics, 7,8 optical elements 9 and mechanical damping. 10,11 Additionally, LCEs are proposed for biomedical applications such as artificial muscle, [12][13][14] scaffolds for tissue engineering, 15 drugdelivery vehicles, 16 vascular implants, 17 interbody fusion cages 18 and synthetic intervertebral disc. 19 However, the proposed biomedical applications mostly focused on either the non-actuation behavior or externally controlled shape-activation.…”

“…Unfortunately, for potential biomedically-related applications, the nematic-isotropic transition temperature is typically upwards from 70 C. 27,28 Recently, only a few researchers have reported LCEs that undergo nematicisotropic transition at a lower temperature. 16,28 Inoue et al fabricated a novel LCE system that shifts diffusivity, rather than shape, at body temperature. 16 Saed et al developed a system of LCEs with highly tailorable nematic-isotropic transition temperature that utilized different mesogens, oligomerization prior to cross-linking and different cross-linking reactions 28 ; however, their method is relatively cumbersome, required intermediate steps, and they did not explore the shape-actuation at body temperature.…”

“…16,28 Inoue et al fabricated a novel LCE system that shifts diffusivity, rather than shape, at body temperature. 16 Saed et al developed a system of LCEs with highly tailorable nematic-isotropic transition temperature that utilized different mesogens, oligomerization prior to cross-linking and different cross-linking reactions 28 ; however, their method is relatively cumbersome, required intermediate steps, and they did not explore the shape-actuation at body temperature. Therefore, there is no existing LCE system for the body-temperature shape-shifting application that can be fabricated using commercially available monomers, and this study aims to develop one.…”

“…Unfortunately, for potential biomedically‐related applications, the nematic‐isotropic transition temperature is typically upwards from 70°C 27,28 . Recently, only a few researchers have reported LCEs that undergo nematic‐isotropic transition at a lower temperature 16,28 . Inoue et al fabricated a novel LCE system that shifts diffusivity, rather than shape, at body temperature 16 .…”

Gemini Thermotropic Smectic Liquid Crystals for Two-Dimensional Nanostructured Water-Treatment Membranes

“…Water purification by membrane filtration is a low-cost and energy-saving method of obtaining high-quality water. − Ordered nanochannels with uniform sizes are essential for achieving high-quality water-treatment membranes . Self-assembly of polymerizable liquid crystals − ,,,− and copolymers − that form nanochannels and nanopores of uniform size has been used for the preparation of functional polymer materials. Self-assembled materials with one-dimensional (1D), 2D, and 3D nanochannels (channel size: 0.5–2 nm) are obtained from nanostructured liquid crystals exhibiting columnar (Col), smectic (Sm), and bicontinuous cubic (Cub bi ) phases, respectively. ,, Block copolymers also form 1D, 2D, and 3D nanochannels (channel size: 5–50 nm). − LC nanostructured polymeric materials have been successfully applied as water-treatment membranes, − organic molecular adsorbents, ,,− and ion conductors. ,,,, …”