1
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Park Y, Song SW, Hong J, Jang H, Lee GR, Kim GY, Jung YS. Si-Containing Reverse-Gradient Block Copolymer for Inorganic Pattern Amplification in EUV Lithography. ACS Macro Lett 2024:943-950. [PMID: 39008631 DOI: 10.1021/acsmacrolett.4c00285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/17/2024]
Abstract
Although extreme ultraviolet lithography (EUVL) has emerged as a leading technology for achieving high quality sub-10 nm patterns, the insufficient pattern height of photoresist patterns remains a challenge. Directed self-assembly (DSA) of block copolymers (BCPs) is expected to be a complementary technology for EUVL due to its ability to form periodic nanostructures. However, for a combination with EUV patterns, it is essential to develop advanced BCP systems that are suited to inorganic-containing EUV photoresists and offer improved resolution limits, pattern quality, and etch resistance. Here, we report a reverse-gradient BCP system, poly[(styrene-gradient-pentafluorostyrene)-b-4-tert-butyldimetilsiloxystyrene] [P(S-g-PFS)-b-P4BDSS] BCP, which enables universally vertically oriented lamellae even in the absence of a neutral layer, while also containing a Si-containing block with high etch resistance. The gradient block, characterized by a gradual compositional transition from the block junction to the tail, plays a crucial role in creating an adequate surface energy contrast that energetically drives the formation of perpendicular lamellae without neutral layer. When used as a pattern height enhancement layer in EUVL, a high aspect ratio (3.29) of patterns was achieved, thereby offering a supplementary solution for next-generation EUVL.
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Affiliation(s)
- Yemin Park
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Seung Won Song
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Jeehyun Hong
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Hanhwi Jang
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Gyu Rac Lee
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Geon Yeong Kim
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Yeon Sik Jung
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
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2
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Sun YS, Jian YQ, Yang ST, Wang HF, Junisu BA, Chen CY, Lin JM. Epitaxial Growth of Surface Perforations on Parallel Cylinders in Terraced Films of Block Copolymer/Homopolymer Blends. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:7680-7691. [PMID: 38551605 PMCID: PMC11008238 DOI: 10.1021/acs.langmuir.4c00385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 03/05/2024] [Accepted: 03/12/2024] [Indexed: 04/10/2024]
Abstract
Due to incommensurability between initial thickness and interdomain distance, thermal annealing inevitably produces relief surface terraces (islands and holes) of various morphologies in thin films of block copolymers. We have demonstrated three kinds of surface terraces in blend films: polygrain terraces with diffuse edges, polygrain terraces with step edges, and pseudo-monograin terraces with island coarsening. The three morphologies were obtained by three different thermal histories, respectively. The thermal histories were imposed on blend films, which were prepared by mixing a homopolystyrene (hPS, 6.1 kg/mol) with a weakly segregated, symmetry polystyrene-block poly(methyl methacrylate) (PS-b-PMMA, 42 kg/mol) followed by spin coating. At a given weight-fraction ratio of PS-b-PMMA/hPS = 75/25, the interior of the blend films forms parallel cylinders. Nevertheless, the surface of the blend films is always dominated by a skin layer of perforations, which epitaxially grow on top of parallel cylinders. By oxygen plasma etching at various time intervals to probe interior nanodomains, the epitaxial relationship between surface perforations and parallel cylinders has been identified by a scanning electron microscope.
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Affiliation(s)
- Ya-Sen Sun
- Department
of Chemical Engineering, National Cheng
Kung University, Tainan 701, Taiwan
| | - Yi-Qing Jian
- Department
of Chemical and Materials Engineering, National
Central University, Taoyuan 32001, Taiwan
| | - Shin-Tung Yang
- Department
of Chemical and Materials Engineering, National
Central University, Taoyuan 32001, Taiwan
| | - Hsiao-Fang Wang
- Department
of Chemical and Materials Engineering, National
Central University, Taoyuan 32001, Taiwan
| | - Belda Amelia Junisu
- Department
of Chemical Engineering, National Cheng
Kung University, Tainan 701, Taiwan
| | - Chun-Yu Chen
- National
Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
| | - Jhih-Min Lin
- National
Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
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3
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Sun YS, Liao YP, Hung HH, Chiang PH, Su CJ. Molecular-weight effects of a homopolymer on the AB- and ABC-stacks of perforations in block copolymer/homopolymer films. SOFT MATTER 2024; 20:609-620. [PMID: 38131364 DOI: 10.1039/d3sm01249b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2023]
Abstract
We have demonstrated the molecular-weight effects of adding homopolystyrene (hPS) on the evolution of perforated layers and double gyroids in polystyrene-block-poly(methyl methacrylate)-based films during isothermal annealing. Two homopolystyrenes of 2.8 and 17 kg mol-1 were used. To prepare blend films, PS-b-PMMA and hPSx (x: 2.8 or 17) were mixed at a weight-fraction ratio of 75/25 in toluene and then spin-coated at SiOx/Si. Spin coating inevitably produced films with thick edges at the periphery of the substrate. The structural evolution of the spun films was in situ characterized by grazing incidence small-angle X-ray scattering (GISAXS). The annealed films were then characterized using a scanning electron microscope (SEM). We found that thin middle regions behaved differently from thick beads for the films. The middle of the blend films mainly formed perforated layers with different spatial orders and orientations, depending on the molecular weight of added hPS chains. Hexagonally perforated layers quickly formed at 205 °C for PS-b-PMMA/hPS2.8 films. However, when hPS17 was used instead of hPS2.8, perforated layers formed with defects in PS-b-PMMA/hPS17 films annealed at 205 °C. Annealing at 240 °C improved the spatial order and orientation of perforated layers for a PS-b-PMMA/hPS17 film. Nevertheless, annealing at 240 °C inversely depressed the in-plane spatial order of perforated layers for a PS-b-PMMA/hPS2.8 film. The depression in the in-plane spatial order is ascribed to a dilution effect of added short chains. Compared to the middle regions, the thick beads went through several metastable phases, such as perpendicularly oriented perforated layers and double gyroids.
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Affiliation(s)
- Ya-Sen Sun
- Department of Chemical Engineering, National Cheng Kung University, Tainan 701, Taiwan.
| | - Yin-Ping Liao
- Department of Chemical and Materials Engineering, National Central University, Taoyuan 32001, Taiwan
| | - Hsiang-Ho Hung
- Department of Chemical and Materials Engineering, National Central University, Taoyuan 32001, Taiwan
| | - Pei-Hsuan Chiang
- Department of Chemical and Materials Engineering, National Central University, Taoyuan 32001, Taiwan
| | - Chun-Jen Su
- National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
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4
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Sun YS, Jian YQ, Yang ST, Chen CY, Lin JM. Morphologies of Surface Perforations and Parallel Cylinders Coexisting in Terraced Films of Block Copolymer/Homopolymer Blends with Oxygen Plasma Etching. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:16284-16293. [PMID: 37934122 DOI: 10.1021/acs.langmuir.3c01784] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2023]
Abstract
This study has demonstrated how oxygen plasma etching carves surface structures for thin films of polystyrene-block-poly(methyl methacrylate)/homopolystyrene blends. By tuning the weight-fraction ratio, blend films form perforations and cylinders on the SiOx/Si substrate. Since perforations exist only on the free surface and substrate interface, short exposure to oxygen plasma to quickly etch the PMMA component produces distorted hexagonal arrays of nanodots on the free surface. The interior of the blend films forms polygrain micro-structures composed of parallel cylinders with an in-plane random orientation. Oxygen plasma etching imposed on the fractured surfaces results in five morphologies: (i) distorted hexagonal arrays of nanoholes, (ii) layer-by-layer stacks, (iii) zigzag-like arrays, (iv) intertwined rectangular arrays of nanodots and nanoholes, and (v) intertwined parallelogram arrays of nanodots and nanoholes. The morphologies suggest synergic effects of grain orientations, stresses, spatial confinement, local segregation of chains, and etching kinetics on the terraced films with oxygen plasma etching.
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Affiliation(s)
- Ya-Sen Sun
- Department of Chemical Engineering, National Cheng Kung University, Tainan 701, Taiwan
| | - Yi-Qing Jian
- Department of Chemical and Materials Engineering, National Central University, Taoyuan 32001, Taiwan
| | - Shin-Tung Yang
- Department of Chemical and Materials Engineering, National Central University, Taoyuan 32001, Taiwan
| | - Chun-Yu Chen
- National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
| | - Jhih-Min Lin
- National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
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5
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Kang L, Wang Q, Zhang L, Zou H, Gao J, Niu K, Jiang N. Recent Experimental Advances in Characterizing the Self-Assembly and Phase Behavior of Polypeptoids. MATERIALS (BASEL, SWITZERLAND) 2023; 16:ma16114175. [PMID: 37297308 DOI: 10.3390/ma16114175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 05/29/2023] [Accepted: 05/31/2023] [Indexed: 06/12/2023]
Abstract
Polypeptoids are a family of synthetic peptidomimetic polymers featuring N-substituted polyglycine backbones with large chemical and structural diversity. Their synthetic accessibility, tunable property/functionality, and biological relevance make polypeptoids a promising platform for molecular biomimicry and various biotechnological applications. To gain insight into the relationship between the chemical structure, self-assembly behavior, and physicochemical properties of polypeptoids, many efforts have been made using thermal analysis, microscopy, scattering, and spectroscopic techniques. In this review, we summarize recent experimental investigations that have focused on the hierarchical self-assembly and phase behavior of polypeptoids in bulk, thin film, and solution states, highlighting the use of advanced characterization tools such as in situ microscopy and scattering techniques. These methods enable researchers to unravel multiscale structural features and assembly processes of polypeptoids over a wide range of length and time scales, thereby providing new insights into the structure-property relationship of these protein-mimetic materials.
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Affiliation(s)
- Liying Kang
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Qi Wang
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Lei Zhang
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Hang Zou
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Jun Gao
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Kangmin Niu
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Naisheng Jiang
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
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6
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Hu M, Li X, Heller WT, Bras W, Rzayev J, Russell TP. Using Grazing-Incidence Small-Angle Neutron Scattering to Study the Orientation of Block Copolymer Morphologies in Thin Films. Macromolecules 2023. [DOI: 10.1021/acs.macromol.2c02415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/17/2023]
Affiliation(s)
- Mingqiu Hu
- Polymer Science and Engineering Department, University of Massachusetts Amherst, 120 Governors Drive, Amherst, Massachusetts 01003, United States
| | - Xindi Li
- Department of Chemistry, University at Buffalo, The State University of New York, Buffalo, New York 14260-3000, United States
| | - William T. Heller
- Neutron Scattering Division, Oak Ridge National Laboratory, P.O. Box 2008,
MS-6473, Oak Ridge, Tennessee 37831, United States
| | - Wim Bras
- Chemical Sciences Division, Oak Ridge National Laboratory, P.O. Box 2008, MS-6131, Oak Ridge, Tennessee 37831, United States
| | - Javid Rzayev
- Department of Chemistry, University at Buffalo, The State University of New York, Buffalo, New York 14260-3000, United States
| | - Thomas P. Russell
- Polymer Science and Engineering Department, University of Massachusetts Amherst, 120 Governors Drive, Amherst, Massachusetts 01003, United States
- Materials Science Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, United States
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7
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TAKAHARA A, ISHIGE R, HIRAI T, NISHIBORI M, HIGAKI Y, YAMAZOE K, HARADA Y. Characterization of Soft Materials by Synchrotron Radiation X-ray Based Scattering and Spectroscopic Techniques. BUNSEKI KAGAKU 2022. [DOI: 10.2116/bunsekikagaku.71.461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Atsushi TAKAHARA
- Research Center for Negative Emission Technologies, Kyushu University
| | - Ryohei ISHIGE
- Department of Chemical Science and Engineering, Tokyo Institute of Technology
| | - Tomoyasu HIRAI
- Department of Applied Chemistry, Faculty of Engineering, Osaka Institute of Technology
| | - Maiko NISHIBORI
- International Center for Synchrotron Radiation Innovation Smart, Tohoku University
| | - Yuji HIGAKI
- Department of Integrated Science and Technology, Faculty of Science and Technology, Oita University
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8
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Iwao S, Kurono N, Higashiguchi W, Hayakawa T, Ohta N, Kamitani K, Fujii S, Nakamura Y, Hirai T. Ordered Silica Nanostructure by the Calcination of Block Copolymer with Polyhedral Oligomeric Silsesquioxane (POSS) Side Chain. CHEM LETT 2022. [DOI: 10.1246/cl.220180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Sota Iwao
- Depaertment of Applied Chemistry, Faculty of Engineering and Graduate School of Engineering, Osaka Institute of Technology, 5-16-1 Omiya, Asahi-ku, Osaka 535-8585, Japan
| | - Naoki Kurono
- Depaertment of Applied Chemistry, Faculty of Engineering and Graduate School of Engineering, Osaka Institute of Technology, 5-16-1 Omiya, Asahi-ku, Osaka 535-8585, Japan
| | - Wataru Higashiguchi
- Depaertment of Applied Chemistry, Faculty of Engineering and Graduate School of Engineering, Osaka Institute of Technology, 5-16-1 Omiya, Asahi-ku, Osaka 535-8585, Japan
| | - Teruaki Hayakawa
- Department of Materials Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, 2-12-1-S8-36 Ookayama, Meguro-ku, Tokyo 152-8552, Japan
| | - Noboru Ohta
- Japan Synchrotron Radiation Research Institute, SPring-8, Sayo, Hyogo 679-5198, Japan
| | - Kazutaka Kamitani
- Aichi Synchrotron Radiation Center, Aichi Science & Technlogy Foudation, 250-3 Minamiyamaguchi-cho, Seto, Aichi 489-0965, Japan
| | - Syuji Fujii
- Depaertment of Applied Chemistry, Faculty of Engineering and Graduate School of Engineering, Osaka Institute of Technology, 5-16-1 Omiya, Asahi-ku, Osaka 535-8585, Japan
| | - Yoshinobu Nakamura
- Depaertment of Applied Chemistry, Faculty of Engineering and Graduate School of Engineering, Osaka Institute of Technology, 5-16-1 Omiya, Asahi-ku, Osaka 535-8585, Japan
| | - Tomoyasu Hirai
- Depaertment of Applied Chemistry, Faculty of Engineering and Graduate School of Engineering, Osaka Institute of Technology, 5-16-1 Omiya, Asahi-ku, Osaka 535-8585, Japan
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9
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Gao X, Yamamoto K, Hirai T, Ohta N, Uchiyama T, Watanabe T, Imai H, Sugawara S, Shinohara K, Uchimoto Y. Impact of the Composition of Alcohol/Water Dispersion on the Proton Transport and Morphology of Cast Perfluorinated Sulfonic Acid Ionomer Thin Films. ACS OMEGA 2021; 6:14130-14137. [PMID: 34124435 PMCID: PMC8190810 DOI: 10.1021/acsomega.1c00607] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 05/13/2021] [Indexed: 06/12/2023]
Abstract
The dispersion of perfluorinated sulfonic acid ionomers in catalyst inks is an important factor that controls the performance of catalyst layers in membrane electrode assemblies of polymer electrolyte fuel cells. Herein, the effects of water/alcohol compositions on the morphological properties and proton transport are examined by grazing incidence small-angle X-ray scattering, grazing incidence wide-angle X-ray scattering, and electrochemical impedance spectroscopy. The thin films cast by a high water/alcohol ratio Nafion dispersion have high proton conductivity and well-defined hydrophilic/hydrophobic phase separation, which indicates that the proton conductivity and morphology of the Nafion thin films are strongly influenced by the state of dispersion. This finding is expected to further understand the morphology and proton transport properties of Nafion thin films with different water/alcohol ratios, which has implications for the performance of the Pt/Nafion interface.
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Affiliation(s)
- Xiao Gao
- Graduate
School of Human and Environmental Studies, Kyoto University, Yoshida nihonmatsu-cho, Sakyo-ku, Kyoto 606-8316, Japan
| | - Kentaro Yamamoto
- Graduate
School of Human and Environmental Studies, Kyoto University, Yoshida nihonmatsu-cho, Sakyo-ku, Kyoto 606-8316, Japan
| | - Tomoyasu Hirai
- Department
of Applied Chemistry, Osaka Institute of
Technology, 5-16-1 Ohmiya, Asahi-ku, Osaka 535-8585, Japan
| | - Noboru Ohta
- Japan
Synchrotron Radiation Research Institute (JASRI), Sayo-gun, Hyogo 679-5198, Japan
| | - Tomoki Uchiyama
- Graduate
School of Human and Environmental Studies, Kyoto University, Yoshida nihonmatsu-cho, Sakyo-ku, Kyoto 606-8316, Japan
| | - Toshiki Watanabe
- Graduate
School of Human and Environmental Studies, Kyoto University, Yoshida nihonmatsu-cho, Sakyo-ku, Kyoto 606-8316, Japan
| | - Hideto Imai
- Nissan
Analysis and Research Center, 1, Natsushima-cho, Yokosuka-shi, Kanagawa 237-8523, Japan
| | - Seiho Sugawara
- Fuel
Cell Cutting-Edge Research Center Technology Research Association, 2-3-26, Aomi, Koto-ku, Tokyo 135-0064, Japan
| | - Kazuhiko Shinohara
- Fuel
Cell Cutting-Edge Research Center Technology Research Association, 2-3-26, Aomi, Koto-ku, Tokyo 135-0064, Japan
| | - Yoshiharu Uchimoto
- Graduate
School of Human and Environmental Studies, Kyoto University, Yoshida nihonmatsu-cho, Sakyo-ku, Kyoto 606-8316, Japan
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10
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Hamamoto H, Takagi H, Akiba I, Yamamoto K. Analysis of Homopolymer Distribution in a Polymer Blend Thin Film by Anomalous Grazing Incidence Small-Angle X-ray Scattering at the Bromine K-Edge. Macromolecules 2020. [DOI: 10.1021/acs.macromol.0c02017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Hiroki Hamamoto
- Department of Life Science and Applied Chemistry, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555, Japan
| | - Hideaki Takagi
- Photon Factory, Institute of Materials Structure Science, High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - Isamu Akiba
- Department of Chemistry and Biochemistry, The University of Kitakyusyu, 1-1 Hibikino, Kitakyusyu 808-0135, Japan
| | - Katsuhiro Yamamoto
- Department of Life Science and Applied Chemistry, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555, Japan
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11
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Gao X, Yamamoto K, Hirai T, Uchiyama T, Ohta N, Takao N, Matsumoto M, Imai H, Sugawara S, Shinohara K, Uchimoto Y. Morphology Changes in Perfluorosulfonated Ionomer from Thickness and Thermal Treatment Conditions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:3871-3878. [PMID: 32168455 DOI: 10.1021/acs.langmuir.9b03564] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The morphological changes of Nafion thin films with thicknesses from 10 to 200 nm on Pt substrate with various annealing histories (unannealed to 240 °C) were systematically investigated using grazing incidence small-angle X-ray scattering (GISAXS) and grazing incidence wide-angle X-ray scattering (GIWAXS). The results revealed that the hydrophilic ionic domain and hydrophobic backbone in Nafion thin films changed significantly when the annealing treatment exceeded the cluster transition temperature, which decreased proton conductivity, due to the constrained hydrophilic/hydrophobic phase separation, and increased the crystalline-rich domain. This research contributed to the understanding of ionomer thermal stability in the catalyst layer, which is subjected to thermal annealing during the hot-pressing process.
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Affiliation(s)
- Xiao Gao
- Graduated School of Human and Environmental Studies, Kyoto University, Yoshida nihonmatsu-cho, Sakyo-ku, Kyoto, 606-8501, Japan
| | - Kentaro Yamamoto
- Graduated School of Human and Environmental Studies, Kyoto University, Yoshida nihonmatsu-cho, Sakyo-ku, Kyoto, 606-8501, Japan
| | - Tomoyasu Hirai
- Department of Applied Chemistry, Osaka Institute of Technology, 5-16-1 Ohmiya, Asahi-ku, Osaka, 535-8585, Japan
| | - Tomoki Uchiyama
- Graduated School of Human and Environmental Studies, Kyoto University, Yoshida nihonmatsu-cho, Sakyo-ku, Kyoto, 606-8501, Japan
| | - Noboru Ohta
- Japan Synchrotron Radiation Research Institute (JASRI), Sayo-gun, Hyogo 679-5198, Japan
| | - Naoki Takao
- Nissan Analysis and Research Center, 1, Natsushimacho, Yokosuka-shi, Kanagawa 237-8523, Japan
| | - Masashi Matsumoto
- Nissan Analysis and Research Center, 1, Natsushimacho, Yokosuka-shi, Kanagawa 237-8523, Japan
| | - Hideto Imai
- Nissan Analysis and Research Center, 1, Natsushimacho, Yokosuka-shi, Kanagawa 237-8523, Japan
| | - Seiho Sugawara
- Fuel Cell Cutting-Edge Research Center Technology Research Association, 2-3-26, Aomi, Koto-ku, Tokyo 135-0064, Japan
| | - Kazuhiko Shinohara
- Fuel Cell Cutting-Edge Research Center Technology Research Association, 2-3-26, Aomi, Koto-ku, Tokyo 135-0064, Japan
| | - Yoshiharu Uchimoto
- Graduated School of Human and Environmental Studies, Kyoto University, Yoshida nihonmatsu-cho, Sakyo-ku, Kyoto, 606-8501, Japan
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12
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Ogawa H, Ono S, Nishikawa Y, Fujiwara A, Kabe T, Takenaka M. Improving grazing-incidence small-angle X-ray scattering-computed tomography images by total variation minimization. J Appl Crystallogr 2020; 53:140-147. [PMID: 32047408 PMCID: PMC6998772 DOI: 10.1107/s1600576719016558] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Accepted: 12/09/2019] [Indexed: 05/30/2023] Open
Abstract
Grazing-incidence small-angle X-ray scattering coupled with computed tomography (CT) has enabled the visualization of the spatial distribution of nanostructures in thin films. In this study, to optimize the CT image quality, total variation regularization is introduced to minimize sinogram image noise and artifacts. Grazing-incidence small-angle X-ray scattering (GISAXS) coupled with computed tomography (CT) has enabled the visualization of the spatial distribution of nanostructures in thin films. 2D GISAXS images are obtained by scanning along the direction perpendicular to the X-ray beam at each rotation angle. Because the intensities at the q positions contain nanostructural information, the reconstructed CT images individually represent the spatial distributions of this information (e.g. size, shape, surface, characteristic length). These images are reconstructed from the intensities acquired at angular intervals over 180°, but the total measurement time is prolonged. This increase in the radiation dosage can cause damage to the sample. One way to reduce the overall measurement time is to perform a scanning GISAXS measurement along the direction perpendicular to the X-ray beam with a limited interval angle. Using filtered back-projection (FBP), CT images are reconstructed from sinograms with limited interval angles from 3 to 48° (FBP-CT images). However, these images are blurred and have a low image quality. In this study, to optimize the CT image quality, total variation (TV) regularization is introduced to minimize sinogram image noise and artifacts. It is proposed that the TV method can be applied to downsampling of sinograms in order to improve the CT images in comparison with the FBP-CT images.
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Affiliation(s)
- Hiroki Ogawa
- Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan.,JST, PRESTO, 4-1-8 Honcho, Kawaguchi, Saitama 332-001, Japan.,Riken SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan
| | - Shunsuke Ono
- JST, PRESTO, 4-1-8 Honcho, Kawaguchi, Saitama 332-001, Japan.,School of Computing, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8503, Japan
| | - Yukihiro Nishikawa
- Department of Macromolecular Science and Engineering, Kyoto Institute of Technology, Kyoto 606-8585, Japan
| | - Akihiko Fujiwara
- Department of Nanotechnology for Sustainable Energy, Kwansei Gakuin University, Hyogo 669-1337, Japan
| | - Taizo Kabe
- Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo, Hyogo 679-5198, Japan
| | - Mikihito Takenaka
- Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan.,Riken SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan
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13
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Spiridon MC, Demazy N, Brochon C, Cloutet E, Hadziioannou G, Aissou K, Fleury G. Optical Alignment of Si-Containing Nanodomains Formed by Photoresponsive Amorphous Block Copolymer Thin Films. Macromolecules 2020. [DOI: 10.1021/acs.macromol.9b01551] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Nils Demazy
- Univ. Bordeaux, CNRS, Bordeaux INP, LCPO, UMR 5629, F-33600 Pessac, France
| | - Cyril Brochon
- Univ. Bordeaux, CNRS, Bordeaux INP, LCPO, UMR 5629, F-33600 Pessac, France
| | - Eric Cloutet
- Univ. Bordeaux, CNRS, Bordeaux INP, LCPO, UMR 5629, F-33600 Pessac, France
| | | | - Karim Aissou
- Univ. Bordeaux, CNRS, Bordeaux INP, LCPO, UMR 5629, F-33600 Pessac, France
| | - Guillaume Fleury
- Univ. Bordeaux, CNRS, Bordeaux INP, LCPO, UMR 5629, F-33600 Pessac, France
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14
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Hydrophobicity enhancement of polyurethanes by attaching fluorinated end blocks via ATRP and correlation between surface properties and self-assembly nature. POLYMER 2019. [DOI: 10.1016/j.polymer.2019.04.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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15
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Kamitani K, Hamada A, Yokomachi K, Ninomiya K, Uno K, Mukai M, Konishi Y, Ohta N, Nishibori M, Hirai T, Takahara A. Depth-Resolved Characterization of Perylenediimide Side-Chain Polymer Thin Film Structure Using Grazing-Incidence Wide-Angle X-ray Diffraction with Tender X-rays. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:8516-8521. [PMID: 29950098 DOI: 10.1021/acs.langmuir.8b01566] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Polymers with a perylenediimide (PDI) side chain (PAc12PDI) consist of two kinds of crystalline structures with various types of orientations in a thin film. Understanding the population of the microcrystalline structure and its orientation along the thickness is strongly desired. Grazing-incidence wide-angle X-ray diffraction (GIWAXD) measurements with hard X-rays, which are generally chosen as λ = 0.1 nm, are a powerful tool to evaluate the molecular aggregation structure in thin films. A depth-resolved analysis for the outermost surface of the polymeric materials using conventional GIWAXD measurements, however, has limitations on depth resolution because the X-ray penetration depth dramatically increases above the critical angle. Meanwhile, tender X-rays (λ = 0.5 nm) have the potential advantage that the penetration depth gradually increases above the critical angle, leading to precise characterization for the population of crystallite distribution along the thickness. The population of the microcrystalline states in the PAc12PDI thin film was precisely characterized utilizing GIWAXD measurements using tender X-rays. The outermost surface of the PAc12PDI thin film is occupied by a monoclinic lattice with a = 2.38 nm, b = 0.74 nm, c = 5.98 nm, and β = 108.13°, while maintaining the c-axis perpendicular to the substrate surface. Additionally, the presence of solid substrate controls the formation of the crystallite with unidirectional orientation.
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Affiliation(s)
| | | | | | | | | | | | | | - Noboru Ohta
- Japan Synchrotron Radiation Research Institute/SPring-8 , Sayo , Hyogo 679-5198 , Japan
| | - Maiko Nishibori
- Research Center for Synchrotron Light Applications , Kyushu University , 6-1 Kasugakoen , Kasuga , Fukuoka 816-8580 , Japan
| | | | - Atsushi Takahara
- Research Center for Synchrotron Light Applications , Kyushu University , 6-1 Kasugakoen , Kasuga , Fukuoka 816-8580 , Japan
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16
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Pang Y, Wan L, Huang G, Zhang X, Jin X, Xu P, Liu Y, Han M, Wu GP, Ji S. Controlling Block Copolymer–Substrate Interactions by Homopolymer Brushes/Mats. Macromolecules 2017. [DOI: 10.1021/acs.macromol.7b00743] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Yuanyuan Pang
- Key
Laboratory of Polymer Ecomaterials, Changchun Institute of Applied
Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun 130022, China
- University of
Chinese Academy of Sciences, Beijing, China
| | - Lei Wan
- HGST, A Western
Digital Company, 5601 Great Oaks Parkway, San Jose, California 95119, United States
| | - Guangcheng Huang
- Key
Laboratory of Polymer Ecomaterials, Changchun Institute of Applied
Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun 130022, China
- University of
Chinese Academy of Sciences, Beijing, China
| | - Xiaosa Zhang
- Key
Laboratory of Polymer Ecomaterials, Changchun Institute of Applied
Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun 130022, China
- University of
Chinese Academy of Sciences, Beijing, China
| | - Xiaosa Jin
- Key
Laboratory of Polymer Ecomaterials, Changchun Institute of Applied
Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun 130022, China
- University of
Chinese Academy of Sciences, Beijing, China
| | - Peng Xu
- College
of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225009, China
| | - Yadong Liu
- Key
Laboratory of Polymer Ecomaterials, Changchun Institute of Applied
Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun 130022, China
| | - Miaomiao Han
- Key
Laboratory of Polymer Ecomaterials, Changchun Institute of Applied
Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun 130022, China
| | - Guang-Peng Wu
- MOE Laboratory of Macromolecular Synthesis and Functionalization, Adsorption and Separation Materials & Technologies of Zhejiang Province, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Shengxiang Ji
- Key
Laboratory of Polymer Ecomaterials, Changchun Institute of Applied
Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun 130022, China
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17
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Characterization of the surface morphology and grain growth near the surface of a block copolymer thin film with cylindrical microdomains oriented perpendicular to the surface. Polym J 2017. [DOI: 10.1038/pj.2017.36] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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18
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Ferrarese Lupi F, Giammaria TJ, Seguini G, Laus M, Dubček P, Pivac B, Bernstorff S, Perego M. GISAXS Analysis of the In-Depth Morphology of Thick PS-b-PMMA Films. ACS APPLIED MATERIALS & INTERFACES 2017; 9:11054-11063. [PMID: 28263052 DOI: 10.1021/acsami.7b01366] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The morphological evolution of cylinder-forming poly(styrene)-b-poly(methyl methacrylate) block copolymer (BCP) thick films treated at high temperatures in the rapid thermal processing (RTP) machine was monitored by means of in-depth grazing-incidence small-angle X-ray scattering (GISAXS). The use of this nondisruptive technique allowed one to reveal the formation of buried layers composed of both parallel- and perpendicular-oriented cylinders as a function of the film thickness (24 ≤ h ≤ 840 nm) and annealing time (0 ≤ t ≤ 900 s). Three distinct behaviors were observed depending on the film thickness. Up to h ≤ 160 nm, a homogeneous film consisting of perpendicular-oriented cylinders is observed. When h is between 160 and 700 nm, a decoupling process between both the air-BCP and substrate-BCP interfaces takes place, leading to the formation of mixed orientations (parallel and perpendicular) of the cylinders. Finally, for h > 700 nm, the two interfaces are completely decoupled, and the formation of a superficial layer of about 50 nm composed of perpendicular cylinders is observed. Furthermore, the through-film morphology affects the nanodomain long-range order, which substantially decreases in correspondence with the beginning of the decoupling process. When the thick samples are exposed to longer thermal treatments, an increase in the long-range order of the nanodomains occurs, without any sensible variation of the thickness of the superficial layer.
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Affiliation(s)
- Federico Ferrarese Lupi
- Laboratorio MDM, IMM-CNR , Via C. Olivetti 2, 20864 Agrate Brianza, Italy
- Nanoscience and Materials Division, Istituto Nazionale Ricerca Metrologica , Strada delle Cacce 91, 10135 Torino, Italy
| | - Tommaso Jacopo Giammaria
- Laboratorio MDM, IMM-CNR , Via C. Olivetti 2, 20864 Agrate Brianza, Italy
- Dipartimento di Scienze e Innovazione Tecnologica, Università del Piemonte Orientale ''A. Avogadro'' , Viale T. Michel 11, 1512 Alessandria, Italy
| | - Gabriele Seguini
- Laboratorio MDM, IMM-CNR , Via C. Olivetti 2, 20864 Agrate Brianza, Italy
| | - Michele Laus
- Dipartimento di Scienze e Innovazione Tecnologica, Università del Piemonte Orientale ''A. Avogadro'' , Viale T. Michel 11, 1512 Alessandria, Italy
| | - Pavo Dubček
- Institut Ruđer Bošković , Bijenička cesta 54, 10000 Zagreb, Croatia
| | - Branko Pivac
- Institut Ruđer Bošković , Bijenička cesta 54, 10000 Zagreb, Croatia
| | - Sigrid Bernstorff
- Elettra-Sincrotrone Trieste , SS 14, Km 163.5, in AREA Science Park, 34149 Basovizza (TS), Italy
| | - Michele Perego
- Laboratorio MDM, IMM-CNR , Via C. Olivetti 2, 20864 Agrate Brianza, Italy
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19
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OGAWA H, TSUJIOKA K, TAKENAKA M, KAMITANI K, SUGIYAMA T, KANAYA T, TAKAHARA A. Depth-Dependent Structural Analyses in PS- b-P2VP Thin Films as Revealed by Grazing Incidence Small Angle Scattering in the Tender Energy Region. KOBUNSHI RONBUNSHU 2017. [DOI: 10.1295/koron.2016-0058] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Hiroki OGAWA
- Institute for Chemical Research, Kyoto University
| | | | - Mikihito TAKENAKA
- Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University
| | | | - Takeharu SUGIYAMA
- Research Center for Synchrotron Light Applications, Kyushu University
| | | | - Atsushi TAKAHARA
- Institute for Material Chemistry and Engineering, Kyushu University
- Research Center for Synchrotron Light Applications, Kyushu University
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20
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Block copolymer thin films: Characterizing nanostructure evolution with in situ X-ray and neutron scattering. POLYMER 2016. [DOI: 10.1016/j.polymer.2016.06.069] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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21
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Majewski PW, Yager KG. Rapid ordering of block copolymer thin films. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2016; 28:403002. [PMID: 27537062 DOI: 10.1088/0953-8984/28/40/403002] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Block-copolymers self-assemble into diverse morphologies, where nanoscale order can be finely tuned via block architecture and processing conditions. However, the ultimate usage of these materials in real-world applications may be hampered by the extremely long thermal annealing times-hours or days-required to achieve good order. Here, we provide an overview of the fundamentals of block-copolymer self-assembly kinetics, and review the techniques that have been demonstrated to influence, and enhance, these ordering kinetics. We discuss the inherent tradeoffs between oven annealing, solvent annealing, microwave annealing, zone annealing, and other directed self-assembly methods; including an assessment of spatial and temporal characteristics. We also review both real-space and reciprocal-space analysis techniques for quantifying order in these systems.
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Affiliation(s)
- Pawel W Majewski
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY, USA. Department of Chemistry, University of Warsaw, Warsaw, Poland
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22
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Sakurai S. Recent developments in polymer applications of synchrotron small-angle X-ray scattering. POLYM INT 2016. [DOI: 10.1002/pi.5136] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Shinichi Sakurai
- Department of Biobased Materials Science; Kyoto Institute of Technology; Matsugasaki Sakyo-ku, Kyoto 606-8585 Japan
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23
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Tanaka D, Mizuno T, Hara M, Nagano S, Saito I, Yamamoto K, Seki T. Evaluations of Mesogen Orientation in Thin Films of Polyacrylate with Cyanobiphenyl Side Chain. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:3737-3745. [PMID: 27031094 DOI: 10.1021/acs.langmuir.6b00538] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The orientation behavior of mesogens in a polyacrylate with cyanobiphenyl (CB) side chain in thin films was investigated in detail by UV-vis absorption spectroscopy and grazing incidence small-angle X-ray scattering (GI-SAXS) measurements using both high-energy X-rays of Cu Kα line (λ = 0.154 nm) and low-energy synchrotron X-rays (λ = 0.539 nm). By changing the film thickness ranging 7-200 nm, it is concluded that the planar orientation is predominant for thin films with thickness below 10-15 nm. This planar mesogen orientation near the substrate surface coexists with the homeotropically aligned CB mesogens in films thicker than 30 nm. For the thinnest 7 nm film, the planar orientation is unexpectedly lost, which is in consort with a disordering of smectic layer structure. Peculiar orienting characteristics of CB mesogen are suggested, which probably stem from the tendency to form an antiparallel arrangement of mesogens due to the strong dipole moment of the terminal cyano group.
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Affiliation(s)
| | | | | | | | - Itsuki Saito
- Department of Materials Science and Engineering, Graduate School of Engineering, Nagoya Institute of Technology , Gokiso, Showa, Nagoya 466-8555, Japan
| | - Katsuhiro Yamamoto
- Department of Materials Science and Engineering, Graduate School of Engineering, Nagoya Institute of Technology , Gokiso, Showa, Nagoya 466-8555, Japan
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24
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Orientation and relaxation behaviors of lamellar microdomains of poly(methyl methacrylate)-b-poly(n-butyl acrylate) thin films as revealed by grazing-incidence small-angle X-ray scattering. Polym J 2016. [DOI: 10.1038/pj.2016.2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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25
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Nakai T, Tanaka D, Hara M, Nagano S, Seki T. Free Surface Command Layer for Photoswitchable Out-of-Plane Alignment Control in Liquid Crystalline Polymer Films. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:909-914. [PMID: 26734930 DOI: 10.1021/acs.langmuir.5b04325] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
To date, reversible alignment controls of liquid crystalline materials have widely been achieved by photoreactive layers on solid substrates. In contrast, this work demonstrates the reversible out-of-plane photocontrols of liquid crystalline polymer films by using a photoresponsive skin layer existing at the free surface. A polymethacrylate containing a cyanobiphenyl side-chain mesogen adopts the planar orientation. Upon blending a small amount of azobenzene-containing side-chain polymer followed by successive annealing, segregation of the azobenzene polymer at the free surface occurs and induces a planar to homeotropic orientation transition of cyanobiphenyl mesogens underneath. By irradiation with UV light, the mesogen orientation turns into the planar orientation. The orientation reverts to the homeotropic state upon visible light irradiation or thermally, and such cyclic processes can be repeated many times. On the basis of this principle, erasable optical patterning is performed by irradiating UV light through a photomask.
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Affiliation(s)
- Takashi Nakai
- Department of Molecular Design and Engineering, Graduate School of Engineering and ‡Nagoya University Venture Business Laboratory, Nagoya University , Furo-cho, Chikusa, Nagoya 464-8603, Japan
| | - Daisuke Tanaka
- Department of Molecular Design and Engineering, Graduate School of Engineering and ‡Nagoya University Venture Business Laboratory, Nagoya University , Furo-cho, Chikusa, Nagoya 464-8603, Japan
| | - Mitsuo Hara
- Department of Molecular Design and Engineering, Graduate School of Engineering and ‡Nagoya University Venture Business Laboratory, Nagoya University , Furo-cho, Chikusa, Nagoya 464-8603, Japan
| | - Shusaku Nagano
- Department of Molecular Design and Engineering, Graduate School of Engineering and ‡Nagoya University Venture Business Laboratory, Nagoya University , Furo-cho, Chikusa, Nagoya 464-8603, Japan
| | - Takahiro Seki
- Department of Molecular Design and Engineering, Graduate School of Engineering and ‡Nagoya University Venture Business Laboratory, Nagoya University , Furo-cho, Chikusa, Nagoya 464-8603, Japan
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