Yoshiki Chujo

Polysilsesquioxanes are regarded as organic–inorganic hybrid materials at a molecular level. We can readily tune the properties of the materials for realizing the desired ones by changing the contents or types of organic components. In addition, the hierarchical structures have potential for generating further characteristics distinctly different from those of the constituents. From this viewpoint, polyhedral oligomeric silsesquioxane (POSS) is attractive as a cornerstone in highly ordered mater

The emission process of the o-carborane dyad with anthracene originating from the twisted intramolecular charge transfer (TICT) state in the crystalline state is described. The anthracene-o-carborane dyad was synthesized and its optical properties were investigated. Initially, the dyad had aggregation- and crystallization-induced emission enhancement (AIEE and CIEE) properties via the intramolecular charge transfer (ICT) state. Interestingly, the dyad presented the dual-emissions assigned to bot

Abstract The concept and representative examples of “element-block polymers” are described. A structural unit consisting of various groups of elements is called an “element-block.” In this review, unique properties of “element-block polymers” composed of organoboron complexes, o-carboranes, and polyhedral oligomeric silsesquioxanes as typical examples of element blocks are illustrated. The design and synthesis of new element-blocks and development of methods forming higher-order structures for r

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTReversible gelation of polyoxazoline by means of Diels-Alder reactionYoshiki Chujo, Kazuki Sada, and Takeo SaegusaCite this: Macromolecules 1990, 23, 10, 2636–2641Publication Date (Print):May 1, 1990Publication History Published online1 May 2002Published inissue 1 May 1990https://pubs.acs.org/doi/10.1021/ma00212a007https://doi.org/10.1021/ma00212a007research-articleACS PublicationsRequest reuse permissionsArticle Views3491Altmetric-Citations234LEARN AB

Our work on the characteristics of organoboron-containing polymers is reviewed. The electronic interaction and correlation involving organoboron complexes are responsible for the optical and electric properties of the polymers. To understand the origins of these properties and apply them to the next generation of new materials, we have gathered not only fundamental knowledge on the electronic states and behaviors of each organoboron complex in the polymers but also on the functions of the polyme

A series of boron ketoiminate derivatives that exhibited clear aggregation-induced emission (AIE) characteristics (in THF: Φ(PL)≤0.01; in the solid state: Φ(PL)=0.30-0.76) were prepared by the reactions of 1,3-enaminoketone derivatives with boron trifluoride-diethyl etherate. The structures and optical properties were investigated by UV-visible spectroscopy, photoluminescent (PL) spectroscopy, and X-ray single-crystal measurements. These results indicate that the AIE characteristics were derived

We report a series of mechanofluorochromic (MFC) compounds based on organoboron complexes with aggregation-induced emission (AIE) characteristics. We synthesized a variety of boron ketoiminates and investigated the effect of the substituents on the optical properties by altering the end groups in the compounds. The synthesized boron ketoiminates showed AIE properties and MFC behavior. Interestingly, the hypsochromic and bathochromic shifts of the emission bands individually observed for boron ke

Organoboron complexes having aggregation- and crystalization-induced emission properties are presented. The series of boron diiminates were synthesized and the emission behaviors of the synthesized compounds were investigated. Finally, it was found that significant enhancement of the emission depended on the crystallinity in the solid states.

Abstract In this article, we describe the structure–property relationships between the polyoctahedral oligomeric silsesquioxane (POSS) fillers and the thermomechanical properties of the polymer composites using polystyrene, poly(methyl methacrylate), and ethylene‐(vinyl acetate) copolymer. We used eight kinds of octa‐substituted aliphatic and aromatic POSS as a filler, and homogeneous polymer composites were prepared with various concentrations of these POSS fillers. From a series of measurement

The control of luminescence properties between fluorescence aggregation-caused quenching and aggregation-induced emission with or without a chemical bond at a single site in boron complexes was accomplished.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPolyoxazoline having a coumarin moiety as a pendant group. Synthesis and photogelationYoshiki Chujo, Kazuki Sada, and Takeo SaegusaCite this: Macromolecules 1990, 23, 10, 2693–2697Publication Date (Print):May 1, 1990Publication History Published online1 May 2002Published inissue 1 May 1990https://pubs.acs.org/doi/10.1021/ma00212a017https://doi.org/10.1021/ma00212a017research-articleACS PublicationsRequest reuse permissionsArticle Views1442Altmetric-Cit

A novel core-shell gold colloid-silk fibroin (SF) bioconjugate was prepared by the protein in situ redox technique at room temperature, in which the tyrosine (Tyr) residue of the SF, having strong electron donating properties, in situ reduced Au(III) ions to Au colloids showing a stable and highly monodispersed nature.

Optically active propeller-shaped cyclic compounds based on planar chiral [2.2]paracyclophane emit intense and bright circularly polarized luminescence (CPL).