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Koguchi R, Jankova K, Tanaka Y, Yamamoto A, Murakami D, Yang Q, Ameduri B, Tanaka M. Altering the bio-inert properties of surfaces by fluorinated copolymers of mPEGMA. Biomater Adv 2023; 153:213573. [PMID: 37562157 DOI: 10.1016/j.bioadv.2023.213573] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 07/20/2023] [Accepted: 07/25/2023] [Indexed: 08/12/2023]
Abstract
Hydrophilic materials display "bio-inert properties", meaning that they are less recognized as foreign substances by proteins and cells. Such materials are often water soluble; therefore, one general approach to enable the use of these materials in various applications deals with copolymerizing hydrophilic monomers with hydrophobic ones to facilitate such resulting copolymers water insoluble. However, reducing the hydrophilic monomer amount may reduce the bio-inert properties of the material. The decrease in bio-inert properties can be avoided when small amounts of fluorine are used in copolymers with hydrophilic monomers, as presented in this article. Even in small quantities (7.9 wt%), the fluorinated monomer, 1,1,1,3,3,3-hexafluoropropan-2-yl 2-fluoroacrylate (FAHFiP), contributed to the improved hydrophobicity of the polymers of the long side-chain poly(ethylene glycol) methyl ether methacrylate (mPEGMA) bearing nine ethylene glycol units turning them water insoluble. As evidenced by the AFM deformation image, a phase separation between the FAHFiP and mPEGMA domains was observed. The copolymer with the highest amount of the fluorinated monomer (66.2 wt%) displayed also high (82 %) FAHFiP amount at the polymer-water interface. In contrast, the hydrated sample with the lowest FAHFiP/highest mPEGMA amount was enriched of three times more hydrophilic domains at the polymer-water interface compared to that of the sample with the highest FAHFiP content. Thus, by adding a small FAHFiP amount to mPEGMA copolymers, water insoluble in the bulk too, could be turned highly hydrophilic at the water interface. The high content of intermediate water contributed to their excellent bio-inert properties. Platelet adhesion and fibrinogen adsorption on their surfaces were even more decreased as compared to those on poly(2-methoxyethyl acrylate), which is typically used in medical devices.
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Affiliation(s)
- Ryohei Koguchi
- AGC Inc. Organic Materials Division, Materials Integration Laboratories, 1-1 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Katja Jankova
- Soft Materials Chemistry, Institute for Materials Chemistry and Engineering, Kyushu University, Build. CE41, 744 Motooka Nishi-ku, Fukuoka 819-0395, Japan; Department of Energy Conversion and Storage, Technical University of Denmark, Elektrovej, Build. 375, 2800 Kongens Lyngby, Denmark
| | - Yukiko Tanaka
- Soft Materials Chemistry, Institute for Materials Chemistry and Engineering, Kyushu University, Build. CE41, 744 Motooka Nishi-ku, Fukuoka 819-0395, Japan
| | - Aki Yamamoto
- Soft Materials Chemistry, Institute for Materials Chemistry and Engineering, Kyushu University, Build. CE41, 744 Motooka Nishi-ku, Fukuoka 819-0395, Japan
| | - Daiki Murakami
- Soft Materials Chemistry, Institute for Materials Chemistry and Engineering, Kyushu University, Build. CE41, 744 Motooka Nishi-ku, Fukuoka 819-0395, Japan
| | - Qizhi Yang
- University of Montpellier, ICGM, CNRS, ENSCM, 34000 Montpellier, France
| | - Bruno Ameduri
- University of Montpellier, ICGM, CNRS, ENSCM, 34000 Montpellier, France.
| | - Masaru Tanaka
- Soft Materials Chemistry, Institute for Materials Chemistry and Engineering, Kyushu University, Build. CE41, 744 Motooka Nishi-ku, Fukuoka 819-0395, Japan.
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Kuo AT, Urata S, Koguchi R, Sonoda T, Kobayashi S, Tanaka M. Effects of Side-Chain Spacing and Length on Hydration States of Poly(2-methoxyethyl acrylate) Analogues: A Molecular Dynamics Study. ACS Biomater Sci Eng 2021; 7:2383-2391. [PMID: 33979126 DOI: 10.1021/acsbiomaterials.1c00388] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Hydration states of polymers are known to directly influence the adsorption of biomolecules. Particularly, intermediate water (IW) has been found able to prevent protein adsorption. Experimental studies have examined the IW content and nonthrombogenicity of poly(2-methoxyethyl acrylate) analogues with different side-chain spacings and lengths, which are HPx (x is the number of backbone carbons in a monomer) and PMCyA (y is the number of carbons in-between ester and ether oxygens of the side-chain) series, respectively. HPx was reported to possess more IW content but lower nonthrombogenicity compared to PMCyA with analogous composition. To understand the reason for the conflict, molecular dynamics simulations were conducted to elucidate the difference in the properties between the HPx and PMCyA. Simulation results showed that the presence of more methylene groups in the side chain more effectively prohibits water penetration in the polymer than those in the polymer backbone, causing a lower IW content in the PMCyA. At a high water content, the methoxy oxygen in the shorter side chain of the HPx cannot effectively bind water compared to that in the PMCyA side chain. HPx side chains may have more room to contact with molecules other than water (e.g., proteins), causing experimentally less nonthrombogenicity of HPx than that of PMCyA. In summary, theoretical simulations successfully explained the difference in the effects of side-chain spacing and length in atomistic scale.
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Affiliation(s)
- An-Tsung Kuo
- Innovative Technology Laboratories, AGC Inc., Yokohama 230-0045, Japan
| | - Shingo Urata
- Innovative Technology Laboratories, AGC Inc., Yokohama 230-0045, Japan
| | - Ryohei Koguchi
- Materials Integration Laboratories, AGC Inc., Yokohama 230-0045, Japan
| | - Toshiki Sonoda
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka 819-0395, Japan
| | - Shingo Kobayashi
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka 819-0395, Japan
| | - Masaru Tanaka
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka 819-0395, Japan
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Kuo AT, Urata S, Koguchi R, Sonoda T, Kobayashi S, Tanaka M. Molecular Dynamics Study on the Water Mobility and Side-Chain Flexibility of Hydrated Poly(ω-methoxyalkyl acrylate)s. ACS Biomater Sci Eng 2020; 6:6690-6700. [PMID: 33320637 DOI: 10.1021/acsbiomaterials.0c01220] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Intermediate water (IW) is known to play an important role in the antifouling property of biocompatible polymers. However, how IW prevents protein adsorption is still unclear. To understand the role of IW in the antifouling mechanism, molecular dynamics simulation was used to investigate the dynamic properties of water and side-chains for hydrated poly(ω-methoxyalkyl acrylate)s (PMCxA, where x indicates the number of methylene carbons) with x = 1-6 and poly(n-butyl acrylate) (PBA) in this study. Since the polymers uptake more water than their equilibrium water content (EWC) at the polymer/water interface, we analyzed the hydrated polymers at a water content higher than that of EWC. It was found that the water molecules interacting with one polymer oxygen atom (BW1), of which most are IW molecules, in PMC2A exhibit the lowest mobility, while those in PBA and PMC1A show a higher mobility. The result was consistent with the expectation that the biocompatible polymer with a long-resident hydration layer possesses good antifouling property. Through the detailed analysis of side-chain binding with three different types of BW1 molecules, we found that the amount of side-chains simultaneously interacting with two BW1 molecules, which exhibit the highest flexibility among the three kinds of side-chains, is the lowest for PMC1A. The high mobility of BW1 is thus suggested as the main factor for the poor protein adsorption resistance of PMC1A even though it possesses enough IW content and relatively flexible side-chains. Contrarily, a maximum amount of side-chains simultaneously interacting with two BW1 molecules was found in the hydrated PMC3A. The moderate side-chain length of PMC3A allows side-chains to simultaneously interact with two BW1 molecules and minimizes the hydrophobic part attractively interacting with a protein at the polymer/water interface. The unique structure of PMC3A may be the reason causing the best protein adsorption resistance among the PMCxAs.
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Affiliation(s)
- An-Tsung Kuo
- Innovative Technology Laboratories, AGC Inc., Yokohama 230-0045, Japan
| | - Shingo Urata
- Innovative Technology Laboratories, AGC Inc., Yokohama 230-0045, Japan
| | - Ryohei Koguchi
- Materials Integration Laboratories, AGC Inc., Yokohama 230-0045, Japan
| | - Toshiki Sonoda
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka 819-0395, Japan
| | - Shingo Kobayashi
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka 819-0395, Japan
| | - Masaru Tanaka
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka 819-0395, Japan
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Kuo AT, Sonoda T, Urata S, Koguchi R, Kobayashi S, Tanaka M. Elucidating the Feature of Intermediate Water in Hydrated Poly(ω-methoxyalkyl acrylate)s by Molecular Dynamics Simulation and Differential Scanning Calorimetry Measurement. ACS Biomater Sci Eng 2020; 6:3915-3924. [DOI: 10.1021/acsbiomaterials.0c00746] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- An-Tsung Kuo
- Innovative Technology Laboratories, AGC Inc., Yokohama 221-8755, Japan
| | - Toshiki Sonoda
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka 819-0395, Japan
| | - Shingo Urata
- Innovative Technology Laboratories, AGC Inc., Yokohama 221-8755, Japan
| | - Ryohei Koguchi
- Materials Integration Laboratories, AGC Inc., Yokohama 230-0045, Japan
| | - Shingo Kobayashi
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka 819-0395, Japan
| | - Masaru Tanaka
- Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka 819-0395, Japan
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Koguchi R, Jankova K, Hayasaka Y, Kobayashi D, Amino Y, Miyajima T, Kobayashi S, Murakami D, Yamamoto K, Tanaka M. Understanding the Effect of Hydration on the Bio-inert Properties of 2-Hydroxyethyl Methacrylate Copolymers with Small Amounts of Amino- or/and Fluorine-Containing Monomers. ACS Biomater Sci Eng 2020; 6:2855-2866. [PMID: 33463271 DOI: 10.1021/acsbiomaterials.0c00230] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Materials exhibiting "bio-inert properties" are essential for developing medical devices because they are less recognized as foreign substances by proteins and cells in the living body. We have reported that the presence of intermediate water (IW) with the water molecules loosely bound to a polymer is a useful index of the bio-inertness of materials. Here, we analyzed the hydration state and the responses to biomolecules of poly(2-hydroxyethyl methacrylate) (PHEMA) copolymers including small amounts of 2-(dimethylamino)ethyl methacrylate (DMAEMA) (N-series) or/and 2,2,2-trifluoroethyl methacrylate (TFEMA) (F-series). The hydration structure was analyzed by differential scanning calorimetry (DSC), the molecular mobility of the produced copolymers by temperature derivative of DSC (DDSC), and the water mobility by solid 1H pulse nuclear magnetic resonance (NMR). Although the homopolymers did not show bio-inert properties, the binary and ternary PHEMA copolymers with low comonomer contents showed higher bio-inert properties than those of PHEMA homopolymers. The hydration state of PHEMA was changed by introducing a small amount of comonomers. The mobility of both water molecules and hydrated polymers was changed in the N-series nonfreezing water (NFW) with the water molecules tightly bound to a polymer and was shifted to high-mobility IW and free water (FW) with the water molecules scarcely bound to a polymer. On the other hand, in the F-series, FW turned to IW and NFW. Additionally, a synergetic effect was postulated when both comonomers coexist in the copolymers of HEMA, which was expressed by widening the temperature range of cold crystallization, contributing to further improvement of the bio-inert properties.
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Affiliation(s)
- Ryohei Koguchi
- Graduate School of Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.,AGC Inc. Organic Materials Division, Materials Integration Laboratories, AGC Inc., 1150 Hazawa-cho, Kanagawa-ku, Yokohama, Kanagawa 221-8755, Japan
| | - Katja Jankova
- Soft Materials Chemistry, Institute for Materials Chemistry and Engineering, Kyushu University, Build. CE41, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.,Department of Energy Conversion and Storage, Technical University of Denmark, Fysikvej, Build. 375, 2800 Kongens Lyngby, Denmark
| | - Yuki Hayasaka
- AGC Inc. Common Base Technology Division, Innovative Technology Laboratories, AGC Inc., 1150 Hazawa-cho, Kanagawa-ku, Yokohama, Kanagawa 221-8755, Japan
| | - Daisuke Kobayashi
- AGC Inc. Common Base Technology Division, Innovative Technology Laboratories, AGC Inc., 1150 Hazawa-cho, Kanagawa-ku, Yokohama, Kanagawa 221-8755, Japan
| | - Yosuke Amino
- AGC Inc. Common Base Technology Division, Innovative Technology Laboratories, AGC Inc., 1150 Hazawa-cho, Kanagawa-ku, Yokohama, Kanagawa 221-8755, Japan
| | - Tatsuya Miyajima
- AGC Inc. Common Base Technology Division, Innovative Technology Laboratories, AGC Inc., 1150 Hazawa-cho, Kanagawa-ku, Yokohama, Kanagawa 221-8755, Japan
| | - Shingo Kobayashi
- Soft Materials Chemistry, Institute for Materials Chemistry and Engineering, Kyushu University, Build. CE41, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Daiki Murakami
- Graduate School of Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.,Soft Materials Chemistry, Institute for Materials Chemistry and Engineering, Kyushu University, Build. CE41, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Kyoko Yamamoto
- AGC Inc. Organic Materials Division, Materials Integration Laboratories, AGC Inc., 1150 Hazawa-cho, Kanagawa-ku, Yokohama, Kanagawa 221-8755, Japan
| | - Masaru Tanaka
- Graduate School of Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.,Soft Materials Chemistry, Institute for Materials Chemistry and Engineering, Kyushu University, Build. CE41, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
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Okuno M, Homma O, Kuo AT, Urata S, Koguchi R, Miyajima T, Ishibashi TA. Molecular Orientations and Conformations of Air/Fluoroalkyl Acrylate Polymer Interfaces Studied by Heterodyne-Detected Vibrational Sum Frequency Generation. Macromolecules 2019. [DOI: 10.1021/acs.macromol.9b00541] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Masanari Okuno
- Department of Chemistry, School of Pure and Applied Sciences, University of TsukubaRINGGOLD, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8571 Japan
| | | | | | | | | | | | - Taka-aki Ishibashi
- Department of Chemistry, School of Pure and Applied Sciences, University of TsukubaRINGGOLD, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8571 Japan
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Jankova K, Javakhishvili I, Kobayashi S, Koguchi R, Murakami D, Sonoda T, Tanaka M. Hydration States and Blood Compatibility of Hydrogen-Bonded Supramolecular Poly(2-methoxyethyl acrylate). ACS Appl Bio Mater 2019; 2:4154-4161. [DOI: 10.1021/acsabm.9b00363] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Katja Jankova
- Soft Materials Chemistry, Institute for Materials Chemistry and Engineering, Kyushu University, Build. CE41, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
- Department of Energy Conversion and Storage, Technical University of Denmark, Elektrovej,
Build. 375, 2800 Kongens Lyngby, Denmark
| | - Irakli Javakhishvili
- Danish Polymer Centre, Department of Chemical and Biochemical Engineering, Technical University of Denmark, Build. 229, 2800 Kongens Lyngby, Denmark
| | - Shingo Kobayashi
- Soft Materials Chemistry, Institute for Materials Chemistry and Engineering, Kyushu University, Build. CE41, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Ryohei Koguchi
- Soft Materials Chemistry, Institute for Materials Chemistry and Engineering, Kyushu University, Build. CE41, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
- AGC Inc. New Product R&D Center, 1150 Hazawa-cho, Kanagawa-ku, Yokohama, Kanagawa 221-8755, Japan
| | - Daiki Murakami
- Soft Materials Chemistry, Institute for Materials Chemistry and Engineering, Kyushu University, Build. CE41, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Toshiki Sonoda
- Soft Materials Chemistry, Institute for Materials Chemistry and Engineering, Kyushu University, Build. CE41, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Masaru Tanaka
- Soft Materials Chemistry, Institute for Materials Chemistry and Engineering, Kyushu University, Build. CE41, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
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Koguchi R, Jankova K, Tanabe N, Amino Y, Hayasaka Y, Kobayashi D, Miyajima T, Yamamoto K, Tanaka M. Controlling the Hydration Structure with a Small Amount of Fluorine To Produce Blood Compatible Fluorinated Poly(2-methoxyethyl acrylate). Biomacromolecules 2019; 20:2265-2275. [PMID: 31042022 DOI: 10.1021/acs.biomac.9b00201] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Poly(2-methoxyethyl acrylate) (PMEA) shows excellent blood compatibility because of the existence of intermediate water. Various modifications of PMEA by changing its main or side chain's chemical structure allowed tuning of the water content and the blood compatibility of numerous novel polymers. Here, we exploit a possibility of manipulating the surface hydration structure of PMEA by incorporation of small amounts of hydrophobic fluorine groups in MEA polymers using atom-transfer radical polymerization and the (macro) initiator concept. Two kinds of fluorinated MEA polymers with similar molecular weights and the same 5.5 mol % of fluorine content were synthesized using the bromoester of 2,2,3,3,4,4,5,5,6,6,7,7,8,8-pentadecafluoro-1-octanol (F15) and poly(2,2,2-trifluoroethyl methacrylate) (PTFEMA) as (macro) initiators, appearing liquid and solid at room temperature, respectively. The fibrinogen adsorption of the two varieties of fluorinated MEA polymers was different, which could not be explained only by the bulk hydration structure. Both polymers show a nanostructured morphology in the hydrated state with different sizes of the features. The measured elastic modulus of the domains appearing in atomic force microscopy and the intermediate water content shed light on the distinct mechanism of blood compatibility. Contact angle measurements reveal the surface hydration dynamics-while in the hydrated state, F15- b-PMEA reorients easily to the surface exposing its PMEA part to the water, the small solid PTFEMA block with high glass-transition temperature suppresses the movement of PTFEMA- b-PMEA and its reconstruction on the surface. These findings illustrate that in order to make a better blood compatible polymer, the chains containing sufficient intermediate water need to be mobile and efficiently oriented to the water surface.
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Affiliation(s)
- Ryohei Koguchi
- Soft Materials Chemistry, Institute for Materials Chemistry and Engineering , Kyushu University , Build. CE41, 744 Motooka , Nishi-ku, Fukuoka 819-0395 , Japan.,AGC Incorporation New Product R&D Center , 1150 Hazawa-cho , Kanagawa-ku, Yokohama , Kanagawa 221-8755 , Japan
| | - Katja Jankova
- Soft Materials Chemistry, Institute for Materials Chemistry and Engineering , Kyushu University , Build. CE41, 744 Motooka , Nishi-ku, Fukuoka 819-0395 , Japan.,Department of Energy Conversion and Storage , Technical University of Denmark , Elektrovej, Build. 375 , 2800 Kongens Lyngby , Denmark
| | - Noriko Tanabe
- AGC Incorporation Innovative Technology Research Center , 1150 Hazawa-cho , Kanagawa-ku, Yokohama , Kanagawa 221-8755 , Japan
| | - Yosuke Amino
- AGC Incorporation Innovative Technology Research Center , 1150 Hazawa-cho , Kanagawa-ku, Yokohama , Kanagawa 221-8755 , Japan
| | - Yuki Hayasaka
- AGC Incorporation Innovative Technology Research Center , 1150 Hazawa-cho , Kanagawa-ku, Yokohama , Kanagawa 221-8755 , Japan
| | - Daisuke Kobayashi
- AGC Incorporation Innovative Technology Research Center , 1150 Hazawa-cho , Kanagawa-ku, Yokohama , Kanagawa 221-8755 , Japan
| | - Tatsuya Miyajima
- AGC Incorporation Innovative Technology Research Center , 1150 Hazawa-cho , Kanagawa-ku, Yokohama , Kanagawa 221-8755 , Japan
| | - Kyoko Yamamoto
- AGC Incorporation New Product R&D Center , 1150 Hazawa-cho , Kanagawa-ku, Yokohama , Kanagawa 221-8755 , Japan
| | - Masaru Tanaka
- Soft Materials Chemistry, Institute for Materials Chemistry and Engineering , Kyushu University , Build. CE41, 744 Motooka , Nishi-ku, Fukuoka 819-0395 , Japan
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Affiliation(s)
- Ryohei Koguchi
- Institute of Materials Science, Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan
| | - Norifumi Kobayashi
- Institute of Materials Science, Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan
| | - Masashi Kijima
- Institute of Materials Science, Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan
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Koguchi R, Kobayashi N, Shinnai T, Oikawa K, Tsuchiya K, Kijima M. Synthesis of Poly(N
-aryl-2,7-carbazole)s for Efficient Blue Electroluminescence Materials. MACROMOL CHEM PHYS 2007. [DOI: 10.1002/macp.200700448] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Affiliation(s)
- Norifumi Kobayashi
- Institute of Materials Science, Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan
| | - Ryohei Koguchi
- Institute of Materials Science, Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan
| | - Masashi Kijima
- Institute of Materials Science, Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan
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12
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