Quartz plates were treated with an azobenzene compound having a triethoxysilyl group to modify the surface with the photosensitive unit and were employed for constructing a nematic liquid crystalline cell.The reversible change in the transmittance of the cell set between two crossed polarizers was induced by alternate exposure to UV and visible light, which resulted in the photoisomerization of the monolayered azobenzene.

Stimuli-sensitive hydrogels changing their volumes and shapes in response to various stimulations have potential applications in multiple fields. However, these hydrogels have not yet been commercialized due to some problems that need to be overcome. One of the most significant problems is that conventional stimuli-sensitive hydrogels are usually brittle. Here we prepare extremely stretchable thermosensitive hydrogels with good toughness by using polyrotaxane derivatives composed of α-cyclodextrin and polyethylene glycol as cross-linkers and introducing ionic groups into the polymer network. The ionic groups help the polyrotaxane cross-linkers to become well extended in the polymer network. The resulting hydrogels are surprisingly stretchable and tough because the cross-linked α-cyclodextrin molecules can move along the polyethylene glycol chains. In addition, the polyrotaxane cross-linkers can be used with a variety of vinyl monomers; the mechanical properties of the wide variety of polymer gels can be improved by using these cross-linkers.

No abstract

No abstract

Optical 3D alignment of nanocylinders has been successfully attained for thin films of a block copolymer (see figure) comprising azobenzene‐containing liquid‐crystalline polymers and poly(ethylene oxide) via photoinduced massive migration. The out‐of‐plane and in‐plane alignments are achieved by controlling the film thickness and selection of linear polarization direction upon illumination, respectively.