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Herein we report a strategy for the design of highly luminescent conjugated polymers by restricting rotation of the polymer building blocks through a microporous network architecture. We demonstrate this concept using tetraphenylethene... more
Herein we report a strategy for the design of highly luminescent conjugated polymers by restricting rotation of the polymer building blocks through a microporous network architecture. We demonstrate this concept using tetraphenylethene (TPE) as a building block to construct a light-emitting conjugated microporous polymer. The interlocked network successfully restricted the rotation of the phenyl units, which are the major cause of fluorescence deactivation in TPE, thus providing intrinsic luminescence activity for the polymers. We show positive "CMP effects" that the network promotes π-conjugation, facilitates exciton migration, and improves luminescence activity. Although the monomer and linear polymer analogue in solvents are nonemissive, the network polymers are highly luminescent in various solvents and the solid state. Because emission losses due to rotation are ubiquitous among small chromophores, this strategy can be generalized for the de novo design of light-emitting materials by integrating the chromophores into an interlocked network architecture.
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Conjugated microporous polymers exhibit a synergistic structural effect on the exceptional uptake of amines, whereas the dense porphyrin units facilitate uptake, the high porosity offers a large interface and the swellability boosts... more
Conjugated microporous polymers exhibit a synergistic structural effect on the exceptional uptake of amines, whereas the dense porphyrin units facilitate uptake, the high porosity offers a large interface and the swellability boosts capacity. They are efficient in the uptake of both vapor and liquid amines, are applicable to various types of amines, and are excellent for cycle use.
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All-solid-state batteries (ASSBs) are promising to be next-generation battery that provides high energy density and intrinsic safety. Research in the field of ASSBs has so far focused on the development of highly conductive solid... more
All-solid-state batteries (ASSBs) are promising to be next-generation battery that provides high energy density and intrinsic safety. Research in the field of ASSBs has so far focused on the development of highly conductive solid electrolytes (SEs). The commercialization of ASSBs requires well-established large-scale manufacturing for sulfide SEs with high ionic conductivity. However, the synthesis for sulfide SEs remains at the laboratory scale with limited scalability owing to their air sensitivity. The liquid-phase synthesis would be an economically viable manufacturing technology for sulfide SEs. Herein, we review a chemical perspective in liquid-phase synthesis that offers high scalability, low cost, and high reaction kinetics. This review provides a guideline for desirable solvent selection based on the solubility and polarity characterized by the donor number and dielectric permittivity of solvents. Additionally, we offer a deeper understanding of the recent works on scalable...
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Nanoporous polymers are becoming increasingly interesting materials for electrochemical applications, as their large surface areas with redox-active sites allow efficient adsorption and diffusion of ions. However, their limited electrical... more
Nanoporous polymers are becoming increasingly interesting materials for electrochemical applications, as their large surface areas with redox-active sites allow efficient adsorption and diffusion of ions. However, their limited electrical conductivity remains a major obstacle in practical applications. The conventional approach that alleviates this problem is the hybridisation of the polymer with carbon-based additives, but this directly prevents the utilisation of the maximum capacity of the polymers. Here, we report a layer-by-layer fabrication technique where we separated the active (porous polymer, top) layer and the conductive (carbon, bottom) layer and used these “layered” electrodes in a supercapacitor (SC). Through this approach, direct contact with the electrolyte and polymer material is greatly enhanced. With extensive electrochemical characterisation techniques, we show that the layered electrodes allowed a significant contribution of fast faradic surface reactions to the...
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Synthesis technology for sulfide-based solid electrolytes based on liquid-phase processing has attracted significant interest in relation to achieving the optimal design for all-solid-state batteries. Herein, guidelines to solvent... more
Synthesis technology for sulfide-based solid electrolytes based on liquid-phase processing has attracted significant interest in relation to achieving the optimal design for all-solid-state batteries. Herein, guidelines to solvent selection for the liquid-phase synthesis of superionic conductor Li7P3S11 are described through systematic examination. 70Li2S–30P2S5 system, a source of Li7P3S11, is treated via a wet chemical reaction using eight organic solvents with different physical and chemical properties (i.e., dielectric constant, molecule structure, and boiling point). We reveal that the solvent’s polarity, characterized by the dielectric constant, plays an important role in the formation of crystalline Li7P3S11 via wet chemical reaction. In addition, acetonitrile (ACN) solvent with a high dielectric constant was found to lead to high-purity crystalline Li7P3S11 and intrinsically high ionic conductivity. Further, solvents with a high boiling point and ring structures that cause s...
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A new concept of the formation of charge transfer (CT) complexes between an intrinsically electron‐donating conjugated microporous polymer and a small molecule acceptor is reported. Spirobifluorene‐based mesoporous organic polymers with... more
A new concept of the formation of charge transfer (CT) complexes between an intrinsically electron‐donating conjugated microporous polymer and a small molecule acceptor is reported. Spirobifluorene‐based mesoporous organic polymers with high porosity and Brunauer–Emmett–Teller surface area are synthesized by the Suzuki‐coupling reaction of spirobifluorene and pyrene monomers. The simple doping of the synthesized mesoporous, electron‐rich, conjugated polymer with 7,7,8,8‐tetracyanoquinodimethane as an acceptor leads to efficient CT complexation in the electron‐donating mesoporous spaces. This results in a high‐speed synthesis (within 5 s), thermally stable compound (up to about 200 °C), and good control of the concentration of donor–acceptor pairs in the CT complex.
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In this research, the synthesis of boron-ketoiminate-containing polymers is reported with large molecular weights (Mn = 20 000) and their optical properties are examined by UV-vis absorption and photoluminescence spectrometries. It is... more
In this research, the synthesis of boron-ketoiminate-containing polymers is reported with large molecular weights (Mn = 20 000) and their optical properties are examined by UV-vis absorption and photoluminescence spectrometries. It is shown that the polymers exhibit strong emission both in the solution and solid states (Φ PL,THF = 0.46-0.80, Φ PL,film = 0.13-0.38). These optical properties can be explained by a donor-acceptor interaction between the boron ketoiminate and the electron-donating comonomer such as fluorene or bithiophene. Furthermore, in the solid states, their emission colors can be successfully tuned from blue to orange by the substituents on the nitrogen atom with the difference of the steric hindrance (λ PL,THF = 464-546 nm, λ PL,film = 486-604 nm).
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Crystallinity and porosity are crucial for crystalline porous covalent organic frameworks (COFs). Here we report synthetic control over the crystallinity and porosity of COFs by managing interlayer interactions based on self-complementary... more
Crystallinity and porosity are crucial for crystalline porous covalent organic frameworks (COFs). Here we report synthetic control over the crystallinity and porosity of COFs by managing interlayer interactions based on self-complementary π-electronic forces. Fluoro-substituted and nonsubstituted aromatic units at different molar ratios were integrated into the edge units that stack to trigger self-complementary π-electronic interactions in the COFs. The interactions improve the crystallinity and enhance the porosity by maximizing the total crystal stacking energy and minimizing the unit cell size. Consequently, the COF consisting of equimolar amounts of fluoro-substituted and nonsubstituted units showed the largest effect. These results suggest a new approach to the design of COFs by managing the interlayer interactions.
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... Additional Information. How to Cite. Murata, H., Sanda, F. and Endo, T. (1998), Synthesis and radical polymerization of a novel acrylamide having an α-helical peptide structure in the side chain. Journal of Polymer Science Part A:... more
... Additional Information. How to Cite. Murata, H., Sanda, F. and Endo, T. (1998), Synthesis and radical polymerization of a novel acrylamide having an α-helical peptide structure in the side chain. Journal of Polymer Science Part A: Polymer Chemistry, 36: 16791682. ...
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A series of activated urethane‐type derivatives of γ‐benzyl‐L‐glutamate were synthesized, and their potential as monomers for polypeptide synthesis was investigated. The derivatives of the focus of this work were a series of... more
A series of activated urethane‐type derivatives of γ‐benzyl‐L‐glutamate were synthesized, and their potential as monomers for polypeptide synthesis was investigated. The derivatives of the focus of this work were a series of N‐aryloxycarbonyl‐γ‐benzyl‐L‐glutamate 1, of which aryl groups were phenyl, 4‐chlorophenyl, and 4‐nitrophenyl. These urethanes 1 were reactive in polar solvents such as dimethylsulfoxide, N,N‐dimethylformamide (DMF), and N,N‐dimethylacetamide (DMAc), and were efficiently converted into poly(γ‐benzyl‐L‐glutamate) (poly(BLG)) under mild conditions; at 60 °C without addition of any catalyst. Among the three urethanes, that having 4‐nitrophenoxycarbonyl group 1c was the most reactive to give poly(BLG) efficiently, as was expected from the highly electron deficient nature of the nitrophenoxycarbonyl group. On the other hand, the urethane 1a having phenoxycarbonyl group was also efficiently converted into poly(BLG), in spite of the intrinsically less electrophilicity ...
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The synthesis and self‐polyaddition of the optically active monomers I‐T(L)‐M and I‐T(D)‐M bearing both isocyanate and hydroxyl groups were examined. I‐T(L)‐M and I‐T(D)‐M were synthesized by reactions of L‐ and D‐tyrosine methyl ester,... more
The synthesis and self‐polyaddition of the optically active monomers I‐T(L)‐M and I‐T(D)‐M bearing both isocyanate and hydroxyl groups were examined. I‐T(L)‐M and I‐T(D)‐M were synthesized by reactions of L‐ and D‐tyrosine methyl ester, T(L)‐M and T(D)‐M, with di‐tert‐butyltricarbonate, respectively. The self‐polyaddition of I‐T(L)‐M and I‐T(D)‐M proceeded smoothly with triethylamine or tert‐butyllithium as the initiator in tetrahydrofuran, affording the optically active linear polyurethanes poly[I‐T(L)‐M] and poly[I‐T(D)‐M] with specific head‐to‐tail structures, where the number‐average molecular weights ranged from 10,000 to 20,000 in excellent yields. The optical properties suggested the idea that poly[I‐T(L)‐M] and poly[I‐T(D)‐M] should have some higher order structures. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 1143–1153, 2004
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This work deals with the cationic ring‐opening polymerization of the cyclic thiocarbonates 5‐benzoyloxymethyl‐5‐methyl‐1,3‐dioxane‐2‐thione (1), 5,5‐dimethyl‐1,3‐dioxane‐2‐thione (2), and 4‐benzoyloxymethyl‐1,3‐dioxane‐2‐thione (3). The... more
This work deals with the cationic ring‐opening polymerization of the cyclic thiocarbonates 5‐benzoyloxymethyl‐5‐methyl‐1,3‐dioxane‐2‐thione (1), 5,5‐dimethyl‐1,3‐dioxane‐2‐thione (2), and 4‐benzoyloxymethyl‐1,3‐dioxane‐2‐thione (3). The polymerization was carried out with 2 mol % trifluoromethanesulfonic acid, methyl trifluoromethanesulfonate, boron trifluoride etherate, or triethyloxonium tetrafluoroborate as the initiator to afford the polythiocarbonate with a narrow molecular weight distribution accompanying isomerization of the thiocarbonate group. The molecular weight of the obtained polymer could be controlled by the feed ratio of the monomer to the initiator and increased when the second monomer was added to the polymerization mixture after the quantitative consumption of the monomer in the first stage. The block copolymerization of 2 and 3 was also achieved, and this supported the idea that the cationic ring‐opening polymerization of these monomers proceeded via a living pro...
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Olefin group‐carrying styrene, 1‐but‐3‐enyl‐4‐vinylbenznene (BVB), was polymerized via atom transfer radical polymerization (ATRP) initiated from C‐methylcalix [4]resorcinarene‐based multifunctional initiator (CRA‐bib) at low conversion... more
Olefin group‐carrying styrene, 1‐but‐3‐enyl‐4‐vinylbenznene (BVB), was polymerized via atom transfer radical polymerization (ATRP) initiated from C‐methylcalix [4]resorcinarene‐based multifunctional initiator (CRA‐bib) at low conversion to produce star polymer [poly(BVB)] with narrow molecular weight distribution (Mw/Mn < 1.35). The copolymerization of styrene (St) with poly(BVB) (Mn = 11,000, Mw/Mn = 1.23) as a macroinitiator afforded star block copolymer [poly(BVB‐b‐St)] with Mn = 35,000 and Mw/Mn = 1.44. The BVB layer of poly(BVB‐b‐St), located between the St shell and the CRA core, was crosslinked by olefin metathesis reaction of olefin groups o the BVB moieties. The removal of the CRA core of the crosslinked poly(BVB‐b‐St) by hydrolysis using KOH as a base gave polymeric hollow sphere [poly(cored crossBVB‐b‐St)] with good solubility in organic solvents. The morphological structure of the poly(cored crossBVB‐b‐St) showed spherical aggregates in THF by scanning electron micros...
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Conjugated microporous polymers (CMPs) are a class of organic porous polymers that combine π-conjugated skeletons with permanent nanopores, in sharp contrast to other porous materials that are not π-conjugated and with conventional... more
Conjugated microporous polymers (CMPs) are a class of organic porous polymers that combine π-conjugated skeletons with permanent nanopores, in sharp contrast to other porous materials that are not π-conjugated and with conventional conjugated polymers that are nonporous. As an emerging material platform, CMPs offer a high flexibility for the molecular design of conjugated skeletons and nanopores. Various chemical reactions, building blocks and synthetic methods have been developed and a broad variety of CMPs with different structures and specific properties have been synthesized, driving the rapid growth of the field. CMPs are unique in that they allow the complementary utilization of π-conjugated skeletons and nanopores for functional exploration; they have shown great potential for challenging energy and environmental issues, as exemplified by their excellent performance in gas adsorption, heterogeneous catalysis, light emitting, light harvesting and electrical energy storage. This review describes the molecular design principles of CMPs, advancements in synthetic and structural studies and the frontiers of functional exploration and potential applications.
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Living cationic ring-opening polymerization under air and water was achieved using a well-defined water-resistant cationic initiator in dichloromethane without purification at ambient temperature.
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Using a bio-inspired cellulose template, new charge transfer (CT) nanoparticles (NPs) with unique emission properties for biomedical imaging are reported.