研究者詳細 - 吉田　嘉晃

論文 - 吉田　嘉晃

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ヘテロクムレン類を原料とした高分子材料の開発招待有り

吉田　嘉晃

化学と工業 ( 日本化学会 ) 73 ( 4 ) 340 - 341 2020年04月

Synthesis of polymethacrylate-bearing benzocyclobutene structure and extension to networked polymer based on thermal isomerization 査読有り

Komeda M., Nagayama S., Yoshida Y., Endo T.

Journal of Polymer Science, Part A: Polymer Chemistry 57 ( 21 ) 2175 - 2180 2019年11月

記述言語：英語掲載種別：研究論文（学術雑誌）

© 2019 Wiley Periodicals, Inc. 1-Benzocyclobutenyl methacrylate-bearing methacrylate (BCBMA) backbone has been synthesized, and radical polymerization of the monomer was performed by utilizing 2, 2′-azobisisobutyronitrile (AIBN) as initiator to result poly-BCBMA. Differential scanning calorimetry (DSC) measurement of the derived poly-BCBMA revealed the lowering of thermal isomerization temperature from that of nonsubstituted benzocyclobutene. The thermal decomposition temperature of BCBMA before and after thermal treatment was confirmed by thermogravimetric analysis (TGA). The results of the TGA observation did not show significant difference in both 5% and 10% weight loss temperature (Td5 and Td10). This result suggests that the thermal conversion of the poly-BCBMA to the networked polymer take place without thermal decomposition of the main chain based on the methacrylate framework. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 2175–2180.

DOI： 10.1002/pola.29495

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Synthesis and decrosslinking of networked polymers having zwitterion structure consisted by cyclic amidine and isothiocyanate 査読有り

Yamauchi A., Yoshida Y., Endo T.

Journal of Polymer Science, Part A: Polymer Chemistry 57 ( 20 ) 2131 - 2137 2019年10月

記述言語：英語掲載種別：研究論文（学術雑誌）

© 2019 Wiley Periodicals, Inc. We have already found that the polymers, which are obtained by the polymerization of 4-vinylphenyl isothoiocyanate after the zwitterion formation with cyclic amidines, are networked through the ionic interaction among the zwitterions becoming insoluble to various solvents. We report here on the results of the reaction of nucleophilic reagents such as amines and alcohols with the zwitterionic adduct to investigate about the decrosslinking through the resolution of ionic interactions. In the model reactions of amines and alcohols with the zwitterion compounds, which were consisted of the phenyl isothiocyanate and cyclic amidines, the reaction of nucleophilic reagents and zwitterionic adducts having methyl group at the 2-position of the amidine proceed quantitatively. Based on the model reaction, such nucleophilic addition was applicable to decrosslinking reaction of the networked polymers containing the zwitterion structure in the side-chain. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 2131–2137.

DOI： 10.1002/pola.29485

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Reprocessable Aliphatic Polydithiourethanes Based on the Reversible Addition Reaction of Diisothiocyanates and Dithiols 査読有り

Yoshida Y., Ohnaka K., Endo T.

Macromolecules 52 ( 16 ) 6080 - 6087 2019年08月

担当区分：筆頭著者記述言語：英語掲載種別：記事・総説・解説・論説等（学術雑誌）

Copyright © 2019 American Chemical Society. Aliphatic polydithiourethanes (PDTUs) were successfully synthesized from diisothiocyanates and dithiols having different values of the carbon atom number. The thermal properties and hydrogen-bonding behavior of PDTUs were studied in detail by using differential scanning calorimetry, thermal gravimetric analysis, temperature dependence nuclear magnetic resonance, Fourier transform infrared-attenuated total reflection, and density functional theory and semiempirical molecular orbital methods. In this work, we demonstrated that the thermal decomposition of PDTUs happened from the cleavage of the C-S bond of the dithiocarbamate moiety in the main chain and also that the active isothiocyanate and thiol groups were reprepared in the terminal of the decomposed polymer (i.e., oligomer). Furthermore, we found that the thermal depolymerization of PDTUs and the repolymerization of dithiourethane oligomers at room temperature proceeded repeatedly a few times.

DOI： 10.1021/acs.macromol.9b00350

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Synthesis and physical properties of poly(urethane)s using vicinal diols derived from acrylate and styrene monomers 査読有り

Akbulut H., Yoshida Y., Yamada S., Endo T.

Journal of Polymer Science, Part A: Polymer Chemistry 57 ( 7 ) 799 - 805 2019年04月

記述言語：英語掲載種別：研究論文（学術雑誌）

© 2019 Wiley Periodicals, Inc. We describe the utilization of four kinds of diol derivatives, representing structural similarity to the well-known and commercially available vinyl monomers such as acrylate, acrylamide, styrene, and N-substituted maleimide. The vinyl monomers are readily converted by dihydroxylation reaction to afford the vicinal diol. The synthesis of poly(urethane)s was performed by the reaction of the vicinal diol with two model diisocyanates, including methylene diphenyl isocyanate (MDI) and hexamethylene diisocyanate (HDI) in the presence of dibutyltin dilaurate to form a series of poly(urethane)s, and the effect of vicinal diol containing a side chain inherited from vinyl monomers on their thermal and mechanical properties was investigated using thermogravimetric analysis, differential scanning calorimetry, and tensile test. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 799–805.

DOI： 10.1002/pola.29328

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Methoxy-group control of helical pitch in stereoregular poly(2-ethynylmethoxynaphthalene) prepared by rhodium complex catalyst 査読有り

Mawatari Y., Yoshida Y., Huang K., Tabata M.

Polymers 11 ( 1 ) 2019年01月

記述言語：英語掲載種別：研究論文（学術雑誌）

© 2019 by the authors. The position of the methoxy group in a poly(n-methoxy-2-ethynylnaphthalene) (PnMeO2EN) was found to control the helical pitch of the π-conjugated polymer in the solid state. These PnMeO2ENs were stereoregularly synthesized using an Rh-complex catalyst in ethanol or toluene as the solvent. The helical structure in the solid phase was confirmed by conventional analytical methods, namely diffuse reflective ultraviolet-visible light (UV-Vis) and Raman spectroscopies, X-ray diffraction, and 13 C cross-polarization magic angle spinning NMR spectroscopy, together with molecular mechanics calculations, because the as obtained polymers were insoluble in common solvents. The color of poly(6-methoxy-2-ethynylnaphthalene) (P6MeO2EN) (yellow or red) depended on the polymerization solvent, whereas no such dependency was observed for the yellow-colored P7MeO2EN and P8MeO2EN. The helical structures energetically optimized by molecular mechanics indicate that the red- and yellow-colored P6MeO2ENs form contracted and stretched helices, respectively. Due to the relatively unconstrained rotations of the 6-methoxynaphthyl moieties, the methoxy groups in P6MeO2EN are less sterically hindered along the helical axis. On the contrary, P7MeO2EN and P8MeO2EN have stretched helices due to the considerable steric hindrance imparted by their methoxy groups. The thermal cis-to-trans isomerization of P6MeO2EN in the contracted-helix form required a somewhat higher temperature than that of the stretched helix.

DOI： 10.3390/polym11010094

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Proposed mechanism for the high-yield polymerization of oxyethyl propiolates with Rh complex catalyst using the density functional theory method 査読有り

Yoshida Y., Mawatari Y., Tabata M.

Polymers 11 ( 1 ) 2019年01月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

© 2019 by the authors. In this study, poly(oxyethyl propiolate)s (POP)s featuring various oxyethylene derivatives are synthesized using a [Rh(norbornadiene)Cl] 2 catalyst. In particular, POPs featuring the normal oxyethylene chain in the side-chain exhibit excellent yields and high molecular weights in methanol and N,N-dimethylformamide at 40 °C, compared with poly(n-alkyl propiolate)s (PnAP)s. The high reactivity of the oxyethyl propiolate (OP) monomers is clarified by considering the time dependences of the polymerization yields of OPs and alkyl propiolates (Aps). Furthermore, the monomer structure and intermediate conformation of the Rh complex are optimized using Density Function theory (DFT) methods (B3LYP/6-31G ** and B3LYP/LANL2DZ) and a polymerization mechanism is proposed.

DOI： 10.3390/polym11010093

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最近のラジカル開環重合の進歩とネットワークポリマーへの展開招待有り査読有り

遠藤　剛，吉田　嘉晃

ネットワークポリマー論文集 ( 合成樹脂工業協会 ) 40 ( 1 ) 45 - 54 2019年01月

Synthesis of polydithiourethanes and their thermal, optical, and mechanical properties originated from monomers structure 査読有り

Yoshida Y., Endo T.

Journal of Polymer Science, Part A: Polymer Chemistry 56 ( 19 ) 2255 - 2262 2018年10月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

© 2018 Wiley Periodicals, Inc. Polyaddition of various diisothiocyanates and dithiols was achieved with triethylamine in dimethylformamide at 25 °C for 12 h under nitrogen, and then the corresponding polydithiourethanes (PDTUs) were obtained with high yield and molecular weight without depending on the monomer structures, although the dithiol monomer of the low nucleophilicity was unsuitable for polyaddition in this system. The chemical and physical properties of the obtained PDTUs such as solvent solubility, glass transition temperature, thermal stability, transparency, refractive index, and tensile strength, were analyzed in detail by gel permeation chromatography, nuclear magnetic resonance, Fourier transform infrared–attenuated total reflection, ultraviolet–visible, differential scanning calorimetry, thermogravimetric analysis, and tensile testing measurements. These results proved that PDTUs and their cast films having the aliphatic diisothiocyanate and dithiol moieties exhibited excellent chemical and physical properties compared to that of the aromatic PDTUs. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 2255–2262.

DOI： 10.1002/pola.29198

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Selective formation of a zwitterion adduct and bicarbonate salt in the efficient CO<inf>2</inf> fixation by N-benzyl cyclic guanidine under dry and wet conditions 査読有り

Yoshida Y., Aoyagi N., Endo T.

Beilstein Journal of Organic Chemistry 14 2204 - 2211 2018年08月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

© 2018 Yoshida et al. The efficient CO2 fixation by N-benzyl cyclic guanidine 1 was achieved by bubbling dry CO2 through CH3CN at 25 °C for 2 h. In addition, the zwitterion adduct 2 and bicarbonate salt 3 were selectively prepared from 1 under dry (in anhydrous CH3CN) and wet (in CH3CN containing an equimolar amount of water for 1) conditions, respectively. Both compounds 2 and 3 were isolated as white solids and their structures were characterized in detail by elemental analysis, FTIR-ATR, solid-state NMR, TGA, and DFT calculation. These analytical results obviously revealed the formation of a zwitterion adduct and bicarbonate salt from N-benzyl cyclic guanidine and CO2. Especially, the zwitterion adduct of the monocyclic guanidine derivative and CO2 was isolated and characterized for the first time.

DOI： 10.3762/bjoc.14.194

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Dependence of color change of vinylethylene carbonate copolymers having N-substituted maleimides on chemical structure by acid-base switching in solution and solid state 査読有り

Yoshida Y., Endo T.

Reactive and Functional Polymers 120 139 - 146 2017年11月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

© 2017 The copolymers of vinylethylene carbonate (VEC) and N-substituted maleimide (NMI) having various N-substituents were synthesized by radical polymerization. The color of P(VEC/NMI)s changed from colorless to red reversibly based on the acid-base switching in solution and solid state. Furthermore, the color depth of P(VEC/NMI) solution and powder changed systematically depending on the electric effect of N-substituents. However, the copolymers of styrene and NMIs barely changed under the same conditions. These color change and depth behaviors of NMI copolymers were analyzed in detail by UV–vis and IR spectra, and the results were also supported by the density functional theory (DFT) calculation for the model compound of maleimide tautomers. Additionally, the powder color of P(VEC/NMI)s changed reversibly before and after exposure to cigarette smoke and vinegar.

DOI： 10.1016/j.reactfunctpolym.2017.10.001

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Synthesis and solid-state properties of crosslinked alternating copolymers of phenyl vinylethylene carbonate and N-substituted maleimides 査読有り

Yoshida Y., Endo T.

Journal of Applied Polymer Science 134 ( 35 ) 2017年09月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

© 2017 Wiley Periodicals, Inc. The copolymers of phenyl vinylethylene carbonate (PVEC) and N-phenylmaleimide were prepared with various monomer feeds by using a radical initiator. These copolymers were crosslinked by aminolysis between hexamethylenediamine (HMDA) and cyclic carbonate moiety in the side-chain to obtain the networked polymers having the hydroxyurethane structure. Furthermore, the crosslinked copolymers having the polar cyclic carbonate in the side-chain were synthesized from PVEC and several bifunctional maleimides, and their double networked polymers were prepared with HMDA. These copolymers and networked polymers exhibited color changes depending on their structures based on the acid–base switching in the solid-state. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45247.

DOI： 10.1002/app.45247

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Strictly Alternating Sequences When Copolymerizing Racemic and Chiral Acetylene Monomers with an Organo-Rhodium Catalyst 査読有り

Yoshida Y., Mawatari Y., Sasaki T., Hiraoki T., Wagner M., Müllen K., Tabata M.

Macromolecules 50 ( 4 ) 1291 - 1301 2017年02月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

© 2017 American Chemical Society. A racemic mixture and two chiral monomers of 2-methyl-1-butyl propiolate, i.e., rac1, R1, and S1, were stereoregularly polymerized with a catalyst, [Rh(norbornadiene)Cl]2, in methanol at 40 °C to obtain the corresponding helical racemic and two chiral polymers, Prac1, PR1, and PS1, and a copolymer, Pco. The 1H and 13C NMR spectra of the racemic and chiral polymers differed, although the NMR spectra of their monomers were the same. The structures of the Pco copolymers with different chiral monomer ratios were analyzed using 1D and 2D NMR, optical rotation, circular dichroism (CD), UV-vis, and computational methods to elucidate the stereochemical effect of the chiral monomers together with the polymerization mechanism. The temperature dependence of 1H and 13C NMR spectra in line shape and intensity indicated that the helical main chain undergoes restricted rotation around the ester methylene bonds −O-CH2- through a three-site jump exchange called an accordion-like helix oscillation (HELIOS). The energetically preferred structures of the helical-sense polymers PR1 or PS1 were simulated using the MMFF94 program. The dependence of the NMR spectral line shapes, optical rotations, and calculated structures on the monomer feed clearly indicated that the copolymers alternatively incorporate R1 and S1 to generate one-handed helical-sense chains. Based on these results, a polymerization mechanism is proposed, explaining a strictly alternating copolymerization that yields helical chains.

DOI： 10.1021/acs.macromol.6b02508

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混合気体から炭酸ガスの高選択的分離を目指した一置換ポリアセチレン膜の開発招待有り

吉田　嘉晃, 馬渡　康輝, 田畑　昌祥

化学工業 ( 化学工業社 ) 68 ( 1 ) 58 - 66 2017年01月

Substituent dependence of imidazoline derivatives on the capture and release system of carbon dioxide 査読有り

Yoshida Y., Aoyagi N., Endo T.

New Journal of Chemistry 41 ( 23 ) 14390 - 14396 2017年01月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

© 2017 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique. The reversible capture-release behaviors of CO2 by imidazoline derivatives bearing several 2-substituents were investigated under dry conditions containing a very small amount of water. The imidazoline having a cyclic guanidine moiety only captured CO2 quantitatively, and then the cyclic guanidine derivative gave the guanidinium bicarbonate by CO2 fixation together with a slight amount of water. In contrast, the imidazolines bearing n-butylthiol and n-pentyl groups never captured CO2 even with the addition of an equimolar amount of water. Furthermore, the binding structure between CO2 and the cyclic guanidine derivative was studied in detail by elemental analysis, FTIR-ATR, solid-state NMR, TGA, and DFT calculations in order to predict the CO2 capture-release mechanisms depending on the imidazoline structure.

DOI： 10.1039/c7nj03133e

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Color change of alternating copolymers with phenyl vinylethylene carbonate and N-phenylmaleimide in a solution and in the solid-state, depending on their structure 査読有り

Yoshida Y., Endo T.

RSC Advances 7 ( 15 ) 9373 - 9380 2017年01月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

© The Royal Society of Chemistry. Radical copolymerization, with various monomer feeds of phenyl vinylethylene carbonate (PVEC) and N-phenylmaleimide (PMI), successfully proceeded through selective vinyl and alternating polymerization to obtain copolymers having the maleimide unit in the main-chain and the five-membered cyclic carbonate group in the side-chain. The structure of these copolymers was analyzed in detail using NMR, IR, and UV-Vis methods. The UV-Vis spectra supported the tautomerization of the maleimide unit based on the solvent effect and the alternating and/or homo sequence constructed depending on the monomer feeds. Furthermore, these copolymers exhibited sensitive and reversible color changes based on acid-base switching not only in solution but also in the solid-state. In particular, the color change in the solid-state occurred immediately after exposure to the amine vapor.

DOI： 10.1039/c6ra28446a

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Synthesis and thermal properties of vinyl copolymers with phenyl vinylethylene carbonate and: N -substituted maleimides undergoing color change with acid-base switching 査読有り

Yoshida Y., Endo T.

Polymer Chemistry 7 ( 44 ) 6770 - 6778 2016年11月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

© 2016 The Royal Society of Chemistry. The radical copolymerization of phenyl vinylethylene carbonate (PVEC) with various vinyl and cyclic monomers successfully proceeded through selective vinyl polymerization. In particular, compared with that of the other vinyl and cyclic comonomers, the copolymerization with the N-substituted maleimides (NMI) exhibited high yield and molecular weight without dependence on the N-substituents, due to construction of a charge-transfer complex between PVEC (electron-donor) and NMI monomers (electron-acceptors). IR and UV-vis spectra of these copolymers suggested that the alternating polymerization proceeded between PVEC and NMI monomers, and also indicated that the malemide moiety formed an enolate tautomer in the presence of sufficiently strong basic reagents. The solution of these copolymers was red in color in basic solvents due to the formation of the enolate tautomer, and the solution color changed with a high sensitivity to acid-base switching. These copolymers also exhibited high thermal stability resulting from the maleimide moiety contained within the main-chain.

DOI： 10.1039/c6py01510g

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Mutual Conversion between Stretched and Contracted Helices and its External Stimuli Induced Drastic Colors and Geometrical Structures Changes of Substituted Polyacetylenes Prepared with an Organo-Rhodium Catalyst 査読有り国際誌

Masayoshi Tabata, Yasuteru Mawatari, Yoshiaki Yoshida, and Takahiro Sasaki

Advances in Science and Technology ( Trans Tech Publications ) 97 18 - 23 2016年10月

Radical polymerization behavior and thermal properties of vinyl ethylene carbonate derivatives bearing aromatic moieties 査読有り

Yoshida Y., Endo T.

Polymer 102 167 - 175 2016年10月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

© 2016 Elsevier Ltd Vinyl ethylene carbonate (VEC) derivatives bearing aromatic moieties were prepared by the catalyzed addition of carbon dioxide (CO2) to butadiene monoxide (BMO) derivatives. The radical polymerization of the VEC monomers was carried out in bulk and solution by using a radical initiator, and those produced polymers were analyzed in detail by IR, NMR, and MALDI-TOF mass methods. These results indicated that radical polymerization of VEC derivatives proceeded through the selective vinyl fashion without depending on the substituents and solvents. Furthermore, the chain transfer reaction occurred easily in NMP and the produced polymer had the NMP moiety in the polymer terminal. The radical polymerization of the bifunctional monomer also proceeded through the vinyl fashion together with the chain transfer reaction in NMP and produced the gelation polymer. Electron-withdrawing of the substituents influenced the thermal property of the produced polymer and bifunctional polymer also obtained the high thermal stability than monofunctional polymer. In this report, the polymerization behavior and property of VEC derivatives bearing aromatic groups was summarized systematically.

DOI： 10.1016/j.polymer.2016.09.002

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Remarkably stretched cis-transoid helices generated in solid phase and solution of poly(carbazole acetylene) prepared using an organorhodium catalyst in Toluene 査読有り

Sasaki T., Yoshida Y., Mawatari Y., Tabata M.

Macromolecules 48 ( 4 ) 889 - 897 2015年02月

記述言語：英語掲載種別：研究論文（学術雑誌）

© 2015 American Chemical Society. A helical π-conjugated poly(N-isobutyl-3-carbazole acetylene), P(iBCzA) was stereoregularly prepared using an [Rh(norbornadine)Cl]2-triethylamine catalyst in toluene at 25 °C to determine the detailed geometrical and spatial structures in a tetrahydrofuran (THF) solution and the solid phase. P(iBCzA), which has a bright orange color, was obtained in a yield of 90%. The 2D NMR spectrum of P(iBCzA) in THF-d8 at 50 °C indicated that an extraordinarily extended helix was produced. The WAXS pattern of P(iBCzA) showed the formation of a tetragonal crystal packed with a remarkably stretched cis-transoid (RESTCT) helix similar to that observed in the solution state. This RESTCT helix was confirmed not to be an energetically stable but a metastable structure using MMFF94 program. The solid phase UV-vis spectrum of P(iBCzA) showed the formation of a radical cation called a polaron because of the very large red shifts compared to that observed in solution without the doping.

DOI： 10.1021/ma5024654

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