OHTANI Hajime

写真a

Affiliation Department etc.

Department of Life Science and Applied Chemistry
Department of Life Science and Applied Chemistry

Title

Professor

Mail Address

E-mail address

Degree

  • Nagoya University -  Doctor of Engineering

External Career

  • 1998.04
    -
    2005.03

    Associate Professor, Graduate School of Engineering, Nagoya University   Associate Professor (as old post name)  

  • 1995.04
    -
    1998.03

    Associate Professor, Center for Integrated Research in Science and Engineering   Associate Professor (as old post name)  

  • 1986.07
    -
    1995.03

    Assistant Professor, School of Engineering, Nagoya University   Research Assistant  

Academic Society Affiliations

  • 2014.03
    -
    Now

    The Society of Rubber Science and Technology, Japan

  • 2012.10
    -
    Now

    Tha Mass Specttrometry Society of Japan

  • 2002.06
    -
    2018.06

    American Chemical Society

  • 1998.04
    -
    Now

    Materials Life Society, Japan

  • 1992.05
    -
    Now

    The Japan Scientist Association

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Field of expertise (Grants-in-aid for Scientific Research classification)

  • Polymer chemistry

  • Analytical chemistry

 

Research Career

  • Study on Degradation and Modification of Polymeric Materials

    Collaboration in Japan   (not selected)  

    Project Year:  1986.01  -  Now

  • Basis and Application of Pyrolysis-Gas Chromatography

    International Collaboration   (not selected)  

    Project Year:  1980.04  -  Now

  • Structural Characterization of Polymers

    International Collaboration   (not selected)  

    Project Year:  1980.04  -  Now

Papers

  • Ultralow-Temperature HPLC using Low-Molecular-Weight Hydrocarbons as Mobile Phases

    Tomohiro Motono, Takayuki Kanayama, Shinya Kitagawa, Yoshinori Iiguni, Hajime Ohtani

    Chromatography ( クロマトグラフィー科学会 )  41 ( 3 ) 109 - 114   2020.10  [Refereed]

    Research paper (scientific journal)   Multiple Authorship

    In ultralow-temperature HPLC, analyte retention is often enhanced, inhibiting elution. To solve this problem, we have investigated the use of low-molecular-weight hydrocarbons, methane and ethane, as the mobile phase in a monolithic ODS column. Analyte retention was successfully reduced by the use of these mobile phases, and elution of mono- and di-chloromethane and n-octane, which were not eluted in our previous work using a liquid nitrogen based mobile phase, was achieved. The analysis of octane structural isomers revealed that, in cryogenic HPLC, the retention of branched octanes was significantly reduced compared to the retention of n-octane, i.e., the retention factor of iso-octane (2,2,4-trimethylpentane) was almost negligible. The retention factors of branched octanes were distributed between those of n-pentane and n-heptane in HPLC at -176°C, whereas, in gas chromatography at 50°C, these values were between those of n-heptane and n-octane.

  • Characterizing chain‐end structures formed during initiation reactions of radical polymerization for MMA‐St‐BA terpolymer using pyrolysis‐gas chromatography/atmospheric pressure chemical ionization high‐resolution time‐of‐flight mass spectrometry

    Kenji Kenji Harata, Shinya Kitagawa, Yoshinori Iiguni, Hajime Ohtani, Tatsuya Ezaki

    Rapid Communication in Mass Spectrometry ( Wiley )  34 ( S2 ) e8691   2020.08  [Refereed]

    Research paper (scientific journal)   Multiple Authorship

    Rationale
    Analyzing polymer end groups using pyrolysis (Py) gas chromatography/mass spectrometry (GC/MS) in multi‐component polymer samples is not an easy task because of the insufficient sensitivity, selectivity, and mass resolution of conventional Py‐GC/MS systems.

    Methods
    A new Py‐GC/MS system using an atmospheric pressure chemical ionization (APCI) source combined with high‐resolution time‐of‐flight mass spectrometry (TOFMS) was used for end‐group analysis of a methyl methacrylate (MMA)‐styrene (St)‐butyl acrylate (BA) terpolymer (P (MMA‐St‐BA)), which was radically polymerized using 2,2′‐azobis(2‐methylbutyronitrile) (AMBN) as an initiator.

    Results
    Five possible pyrolyzates, comprising an AMBN fragment and a monomer unit, formed during the initiation reactions from one of the three types of end groups, were selectively detected and exclusively identified in their respective extracted ion chromatograms for molecule‐related ions, such as M+ and [M + H]+, with a narrow mass window of ±2 milli m/z units.

    Conclusions
    It was demonstrated that Py‐APCI‐TOFMS is a powerful technique to characterize in detail the complex end groups in multi‐component polymer samples, because of the soft ionization nature of APCI and the high mass resolution of TOFMS.

  • Online fast pyrolysis of cellulose over titanium dioxide using tandem micro-reactor-GC-MS

    Hiroto Ida, Hajime Ohtani, Selhan Karagöz

    Sustainable Chemistry and Pharmacy ( Elsevier )  16   100268   2020.06  [Refereed]

    Research paper (scientific journal)   Multiple Authorship

    In this work, the catalytic effect of titanium dioxide (TiO2) on the online fast pyrolysis of cellulose was investigated using a tandem micro reactor coupled to a gas chromatograph-mass spectrometer (GC-MS) system. This system was used in the following two different modes: in-situ and ex-situ. The results obtained with TiO2 were compared with those of zeolite (HZSM-5) under identical pyrolysis conditions. Levoglucosan was the major product in the non-catalytic pyrolysis of cellulose. As for the catalytic pyrolysis of cellulose at 500 °C with TiO2 (in-situ), the peak of levoglucosan disappeared whereas aromatic hydrocarbons such as benzene, toluene and naphthalene were newly detected. In this case, oxygenated compounds such as furfural, furan, methylfuran were still observed for TiO2 whereas oxygenated compounds (i.e, furan, benzofuran, methylbenzofuran, acetone and 2-butanone) with low yields were observed for in-situ catalytic pyrolysis with HZSM-5. For ex-situ catalytic pyrolysis of cellulose at 500 °C using TiO2, oxygen-containing compounds were hardly formed, while various aromatic hydrocarbons were detected. When the ex-situ pyrolysis of cellulose with HZSM-5 was carried out, the yields of the aromatic hydrocarbons were comparable to those with TiO2.

  • Identification of polymer species in a complex mixture by pyrolysis-gas chromatography-atmospheric pressure chemical ionization-high resolution time-of-flight mass spectrometry as a basis for environmental microplastic analysis

    Kenji Harata, Shinya Kitagawa, Yoshinori Iiguni, Hajime Ohtani

    Journal of Analytical and Applied Pyrolysis ( Elsevier )  148   104828   2020.06  [Refereed]

    Research paper (scientific journal)   Multiple Authorship

    Pyrolysis-gas chromatography coupled with atmospheric pressure chemical ionization-high resolution time-of-flight mass spectrometry (Py-GC-APCI-TOFMS) was applied for the reliable identification of polymer species in a complex mixture to establish this system as a platform for environmental microplastic analysis. The method was evaluated on a model sample of mixed microplastics comprised of five major polymers: polyethylene (PE), polypropylene (PP), poly(vinyl chloride) (PVC), polystyrene (PSt), and poly(ethylene terephthalate) (PET). The representative ions in the mass spectra of the pyrolyzates were identified by Py-GC-APCI-TOFMS measurements of the individual polymer species. The unique APCI ionization/fragmentation process and the high mass resolution of TOFMS were exploited to confirm the presence of the respective polymer species in the extracted ion chromatograms (EICs) of the mixed sample for the selected key ions. PE and PP were successfully and uniquely identified in the mixed sample by focusing on specific fragment ions of the pyrolyzates formed during APCI (m/z 114.093 ± 0.020 and m/z 156.139 ± 0.020, respectively). The resultant EICs allowed for the specific analysis of these species, even in the presence of interfering species produced from the other polymers. Similar processes were applied to the detection of PVC, PSt, and PET in the mixed sample. These results demonstrated that Py-GC-APCI-TOFMS is a promising tool to characterize a complex mixture of environmental microplastics.

  • Identification algorithm for polymer mixtures based on Py-GC/MS and its application for microplastic analysis in environmental samples

    Kazuko Matsui,Takahisa Ishimura, Marco Mattonai, Itsuko Iwai, Atsushi Watanabe, Norio Teramae, Hajime Ohtani, Chuichi Watanabe

    Journal of Analytical and Applied Pyrolysis ( Elsevier )  149   104834   2020.06  [Refereed]

    Research paper (scientific journal)   Multiple Authorship

    Microplastics pollution is an acknowledged global issue, and new strategies are required to meet the increasing demand of standardized, fast and reliable measurements. Analytical pyrolysis coupled to gas chromatography and mass spectrometry (Py-GC/MS) is a promising technique to obtain qualitative and quantitative data on microplastics mixtures through the selection of a set of characteristic pyrolysis products for each polymer. However, this data processing method is time-consuming, and no automated algorithms are currently available. In the present work, a new method for the qualitative analysis of eleven types of synthetic polymers was developed, automated and implemented in the F-Search software, with the aim of proposing a standardized procedure for data processing in Py-GC/MS analysis of plastics mixtures. The method improves on the current literature, and is based on the generation of summated mass spectra (SMS) for each polymer, obtained by extracting specific m/z and retention index coordinates corresponding to characteristic pyrolysis products. The identification of a polymer is performed by comparing its SMS with those of a built-in library. After validation, the algorithm was tested on a reference sample containing all eleven investigated polymers. The algorithm provided relative standard deviations around 10%, and the results were used to estimate the lowest amount of polymer detectable in a sample, which was found lower than 1 μg for most polymers. The performance of the algorithm was also evaluated on a real sample from ocean water trawling, providing positive results for four different polymers. The performances of the algorithm are discussed, and possible future developments are outlined.

  • Ultraviolet Curing Reaction of Acrylic-maleimideBifunctional Monomer Analyzed by MALDI-MS

    Shotaro Kato, Yoshinori Iiguni, Hajime Ohtani, Hideki Matsubara

    Journal of Network polymer, Japan   41 ( 3 ) 129 - 136   2020.05  [Refereed]

    Research paper (scientific journal)   Multiple Authorship

    The curing reaction of N-(3,4,5,6-tetrahydrophthalimide)ethyl acrylate (THPA), which is a bifunctional monomer having acryloyl and maleimide groups, under ultraviolet (UV) irradiation was analyzed by MALDI-MS. In the case of UVirradiation to THPA alone, the formation of THPA oligomers up to a heptamer was confirmed by the mass spectroscopy.This result indicates that not only the photodimerization of maleimides but also the intermolecular radical coupling between maleimide and acryloyl groups are caused by UV-irradiation to THPA without photoinitiator. A mixture of THPA and neopentyl glycol diacrylate (NPGDA) was then UV-irradiated in the presence of a photoinitiator, hydroxy-2-methylpropiophenone (HMPP), to form a cured sample, which was subjected to supercritical methanolysis. The two series of methyl acrylate oligomers having a THPA unit at a chain end were identified by the MALDI-MS of the methanolysis product. This observation suggests that the UV-curing of THPA-NPGDA in the presence of HMPP might proceed by the polymerization of acryloyl groups initiated not only with a radical formed by the dissociation of HMPP but also with that formed on maleimide moiety.

  • Evaluation of the Interactions Between Palladium(II) and N,N'-Dimethyl-N,N'-di-n-hexyl-thiodiglycolamide in the Presence of Surfactants Using Capillary Electrophoresis

    Nana TANAKA, Shinya KITAGAWA, Hajime OHTANI, Yuki IWAMA, Koichiro KONDO, Yuzo ISHIGAKI, Nobuyuki SHIBATA, Takehiko KINOSHITA, Yuki KAMIMOTO, Ryoichi ICHINO

    Chromatography   40 ( 2 ) 59 - 63   2019.06  [Refereed]

    Research paper (scientific journal)   Multiple Authorship

  • Frequency division multiplex HPLC-MS for simultaneous analyses

    Hiroka Kishi, Takashi Kumazaki, Shinya Kitagawa, Hajime Ohtani

    Analyst   144   2922 - 2928   2019.04  [Refereed]

    Research paper (scientific journal)   Multiple Authorship

  • Electrospray ionization-ion mobility spectrometry-high resolution tandem mass spectrometry with collision induced charge stripping for analysis of highly multiply charged intact polymers

    Yuka Ozeki, Mizuki Omae, Shinya Kitagawa, Hajime Ohtani

    Analyst   144   3428 - 3435   2019.04  [Refereed]

    Research paper (scientific journal)   Multiple Authorship

  • Analysis of Multiply Charged Poly(ethylene oxide-co-propylene oxide) Using Electrospray Ionization–Ion Mobility Spectrometry–Mass Spectrometry

    Kanako ITO, Shinya KITAGAWA, Hajime OHTANI

    Analytical Sciences   35 ( 2 ) 169 - 174   2019.02  [Refereed]

    Research paper (scientific journal)   Multiple Authorship

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Books

  • Practical Gas Chromatography

    Shin TSUGE, Hajime OHTANI (Part: Allotment Writing )

    Springer  2014.12 ISBN: 978-3-642-54640-2

  • Pyrolysis-GC/MS Data Book of Synthetic Polymers

    TSUGE Shin, OHTANI Hajime, WATANABE Chuichi (Part: Multiple Authorship )

    Elsevier  2011.10 ISBN: 978-0-444-53892-5

    This data book provides an extensive reference collection of the behavior of specific polymers during pyrolysis. It fills a big gap in the available standards and data on pyrolysis research, as there are no books that give the same combination of excellent analytical data with such a wide range of polymer systems that are useful to so many areas of multidisciplinary research. The data provided will be useful whenever a new polymer has to be analyzed in order to facilitate the identification or to confirm the results. The book also briefly reviews the instrumentation available in advanced analytical pyrolysis and offers guidance to perform this technique, effectively combining gas chromatography and mass spectrometry. Main contents are comprehensive sample pyrograms, thermograms, identification tables, and representative mass spectra (MS) of pyrolyzates for synthetic polymers. This edition also highlights thermally assisted hydrolysis and methylation techniques effectively applied to 33 basic condensation polymers.

  • Recent Trends of LED-UV Curing Technology and Curing Materials, "jointly worked"

    H. Ohtani (Part: Multiple Authorship )

    CMC Publishing  2010.05 ISBN: 978-4-7813-0221-8

  • Introduction to Polymer Analysis, "jointly works"

    H. Ohtani (Part: Multiple Authorship )

    2010.04 ISBN: 978-4-06-154360-7

  • Conservation of Paper and Books

    H. Ohtnai (Part: Multiple Authorship )

    Iwata-shoin  2009.10 ISBN: 978-4-87294-574-4

  • Crosslinking and Degradation of Polymers for Sustainable Chemistry

    H. Ohtani (Part: Multiple Authorship )

    CMC Publishing  2007.07 ISBN: 978-4-88231-693-0

  • The Fifth Series of Experimental Chemistry 20-1 Analytical Chemistry, "jointly worked"

    H. Ohtani (Part: Multiple Authorship )

    Maruzen  2007.01 ISBN: 978-4-621-07319-3

  • Applied Pyrolysis Handbook second edition, "jointly worked"

    H. Ohtani, S. Tsuge (Part: Multiple Authorship ,  4. Microstructure of Polyolefins, pp.65-80; 5. Degradation Mechanism of Condensation Polymers:Polyesters and Polyamides, pp.81-103;11. Characterization of Condensation Polymers by Pyrolysis-GC in the Presence of Organic Alkali, pp.249-269 )

    CRC Press  2007.01 ISBN: 1-57444-641-X

  • Pyrolysis GC/MS of Highpolymers - Fundamentals and Pyrograms -, "jointly worked"

    S. Tsuge, H. Ohtani, C. Watanabe (Part: Multiple Authorship )

    Technosystem  2006.10 ISBN: 4-924728-51-9

  • Analytical Chemistry, 6th edition, "jointry worked"

    H. Ohtani (Part: Joint Translation )

    Maruzen  2005.03 ISBN: 978-4-621-07554-8

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Review Papers

  • Polymer Analysis by Analytical Pyrolysis

    Journal of the Mass Spectrometry Society of Japan   68 ( 681 ) 13 - 18   2020.09  [Refereed]  [Invited]

    Introduction and explanation (scientific journal)   Single Author

  • Development of Frequency Division Multiplex LC-MS for Simultaneous Analyses

      68 ( 1 ) 13 - 18   2020.02  [Refereed]  [Invited]

    Introduction and explanation (scientific journal)   Multiple Authorship

  • Rapid Evaluation of The Weatherrability of polymers bu Xenon Lamp-Based Online Ultraviolet Irradiation-Pyrolysis-GC/MS

    Science and Industry   88 ( 1 ) 19 - 27   2014.01

    Introduction and explanation (others)   Multiple Authorship

  • Evaluation of Acidic Paper Deterioration in Library Materials by Pyrolysis-Gas Chromatography

    Hajime Ohtani

    Senri Ethnological Studies ( 国立民族学博物館 )  85   11 - 19   2013.12

    Introduction and explanation (others)   Single Author

    Pyrolysis-gas chromatography (Py-GC) was used to evaluate deteriorated acidic paper in old books. A tiny piece (ca. 0.25 mg) of deteriorated paper from each book was subjected to Py-GC measurement at a 300 °C pyrolysis temperature. Levoglucosan and its dehydrated form levoglucosenone were typical degradation products, whereas primarily only levoglucosan was observed in control samples of undamaged new paper. The relative intensity of levoglucosenone was much higher in samples taken at the heavily deteriorated marginal edge than in those taken from the center of the same page of an old book. Accordingly, levoglucosenone observed in the pyrogram can be used as a marker to evaluate the degree of deterioration of acidic paper. The formation of levoglucosenone can be attributed to the slow deterioration process of paper, in which the dehydration reaction plays an important role, accompanied by the chain scission of cellulose. The Py-GC method for paper evaluation was also applied to clarify the effect of storage conditions on the deterioration of paper materials and to evaluate the long-term deterioration of the British Parliamentary Papers (1801–1986) collected at the Kyoto University Library.

  • Direct Analysis of Stabilizers in Plastic Materials by Pyrolysis-GC and MALDI-MS

      47 ( 10 ) 336 - 344   2012.10

    Introduction and explanation (international conference proceedings)   Single Author

  • Polymer Characterization by Mass Spectrometry

    OHTANI Hajime

    Journal of Network Polymer, Japan ( Japan Thermosetting Plastic Industry Association )  32 ( 4 ) 219 - 227   2011.07

    Introduction and explanation (international conference proceedings)   Single Author

  • Ongoing study on the conservation of paper and books: evaluating paper deterioration and strengthening of deteriorated paper

    H, Sonoda, M. Seki, T. Okayama, H. Ohtani

    International Preservation News ( The International Federation of Library Associations and Institutions )  48   27 - 29   2009.08

    Introduction and explanation (international conference proceedings)   Multiple Authorship

  • Structural Characterization of UV-cured Acrylic Ester Resins by Specific Sample Decomposition

    H. Ohtani

    Journal of Network Polymer, Japan ( Japan Thermosetting Plastics Industry Association )  30 ( 1 ) 23 - 32   2009.02

    Introduction and explanation (international conference proceedings)   Single Author

Presentations

  • Analytical Pyrolysis for Environmental Microplastic Analysis: Challenges and Solutions

    大谷 肇  [Invited]

    PyroAsia2020  (オンライン)  2020.12  -  2020.12  PyroAsia組織委員会

  • エレクトロスプレーイオン化イオンモビリティ衝突誘起解離タンデム型質量分析法によるポリブチレンテレフタレートの末端構造解析

    森本雄貴, 北川慎也, 大谷 肇, 川口邦明, 阿久津裕明

    第68回質量分析総合討論会  (オンライン)  2020.05  -  2020.05  日本質量分析学会

  • Identification of polymer species in complex mixture samples by pyrolysis-gas chromatography-atmospheric pressure chemical ionization quadrupole time-of-flight mass spectrometry (Py-APGC-MS) as a basic research for environmental microplastics

    H. Ohtani,K. Harata

    5th International Symposium on Advances in Sustainable Polymers (ASP-19)  (京都工芸繊維大学)  2019.10  -  2019.10 

  • Thermal degradation reaction of 4-vinylpyridine-divinylbenzene copolymer in acetic acid studied by pyrolysis-GC-MS and MALDI-MS

    Y. Ogawa, H. Ohtani, K. Urasaki, R. Kanai

    32nd International Symposium on Polymer Analysis and Characterization (ISPAC2019)  2019.06  -  2019.06 

  • End group analysis of poly(methyl methacrylate) using electrospray ionization-ion mobility-tandem mass spectrometry

    M. Omae, Y. Ozeki, S. Kitagawa, H. Ohtani

    RSC Tokyo International Conference 2018  (幕張メッセ)  2018.09  -  2018.09  日本分析化学会

  • Frequency division multiplex LC-MS for simultaneous analyses of plural samples

    H. Kishi, T. Kumazaki, S. Kitagawa, H. Ohtani

    RSC Tokyo International Conference 2018  (幕張メッセ)  2018.09  -  2018.09  日本分析化学会

  • Thermal decomposition reaction of cured phenol resin in hydrogen donor solvent studied by pyrolysis-GC-MS and MALDI-MS

    Hajime Ohtani, Ryota Kano

    The 10th International Conference of Modification, Degradation and Stabilization of Polymers  (東京大学)  2018.09  -  2018.09  MoDeSt組織委員会

  • Separation of Water-insoluble and Neutral Linear Synthetic Polymer in Non-aqueous Electrophoresis Using Ionic Surfactant

    S. Kitagawa, N. Fukai, S. Uchida, K. Usui, H. Ohtani

    25th International Symposium on Electro- and Liquid Phase-Separation Techniques (ITP2018)  (京都大学桂キャンパス)  2018.08  -  2018.09  ITP2018組織委員会

  • A Novel Multiplex LC-MS Based on Frequency Division Multiplexing for Simultaneous Analyses of Plural Samples

    H. Kishi, T. Kumazaki, S. Kitagawa, H. Ohtani

    25th International Symposium on Electro- and Liquid Phase-Separation Techniques (ITP2018)  (京都大学桂キャンパス)  2018.08  -  2018.09  ITP2018組織委員会

  • HPLC at ultralow-temperatures

    S. Kitagawa, T. Motono, H. Ohtani  [Invited]

    2018 Sino-Japanese Joint Symposium on Separation Sciences  (中国科学院大連化学物理研究所)  2018.07  -  2018.07  中国科学院大連化学物理研究所

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Grant-in-Aid for Scientific Research

  • Applicability of Cellulose Nanofibers for the Conservation of Paper

    Grant-in-Aid for Scientific Research(B)

    Project Year: 2015.04  -  2018.03 

 
 

Academic Activity

  • 2020.04
    -
    Now

    The Japan Society for Analytical Chemistry  

  • 2020.03
    -
    Now

    The Chemical Society of Japan  

  • 2019.05
    -
    Now

    The Japan Society for Analytical Chemistry  

  • 2018.06
    -
    2019.08

    Materials Life Society, Japan  

  • 2018.03
    -
    Now

    The Japan Society for Analytical Chemistry  

  • 2018.03
    -
    2020.02

    The Chemical Society of Japan  

  • 2016.04
    -
    Now

    Tha Mass Specttrometry Society of Japan  

  • 2016.03
    -
    2017.02

    The Japan Society for Analytical Chemistry  

  • 2014.04
    -
    Now

    The Japan Society for Analytical Chemistry  

  • 2014.04
    -
    2015.03

    The Japan Society for Analytical Chemistry  

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