POLYMERS Vol.68 No.6
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Carbon Polymers
COVER STORY: Highlight Reviews
Carbon Nanotubes as a Polymer Tsuyohiko FUJIGAYA
<Abstract> Carbon nanotubes (CNTs) can be recognized as a polymer with π-conjugated one-dimensional cylindrical structure. On the other hand, CNTs can be understood as a nanoparticle since it has a large surface area consisting of a hydrophobic graphitic surface. Both aspects are quite important to explain the properties of the dispersion of CNTs in dispersant molecules such as surfactants. Recent developments of the CNT dispersion technology enables a precise separation of the single-walled carbon nanotubes (SWNT) with different diameter and extraction of the semiconducting SWNTs together with a novel polymer coating technique. These findings will be explained by classical colloid science and will lead to new applications of CNTs.
Keywords: Carbon Nanotube / Dispersion / Colloid / Semiconducting / Polymer Coating / Surface Engineering / Near IR / Surfactant
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Bottom-Up Synthesis of Graphene Nanoribbons as Structurally Well-Defined, Quasi-One-Dimensional Carbon Materials Akimitsu NARITA
<Abstract> Bottom-up synthesis can provide graphene nanoribbons (GNRs) with well defined structures. In addition to solution synthesis based on conventional methods of organic and polymer chemistry, on-surface synthesis based on the modern methods of surface science enabled fabrication of various GNRs with different structures and unique properties. This article provides an overview of the field, including introduction of different polymerization methods for the solution synthesis of GNRs, edge functionalization of GNRs for achieving novel properties, and the latest developments in the on-surface synthesis of GNRs.
Keywords: Graphene / Graphenene Nanoribbon / Polycyclic Aromatic Hydrocarbon / Cyclodehydrogenation / Suzuki Polymerization / Yamamoto Polymerization / Diels-Alder Polymerization / Surface Synthesis
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Liquid Nanocarbons Takashi NAKANISHI
<Abstract> Nanocarbons, i.e. fullerenes, carbon nanotubes, and graphene, have been pulling the scientific fields of nano-science and materials chemistry for over 20 years, due to their intrinsic unique structural geometry, excellent reactivity, optoelectronic functions as well as mechanical properties. Materialization by liquefaction of those nanocarbons is an unprecedented and quite exotic methodology. The key technique for the purpose is basically reducing their π-π interactions by attaching bulky and flexible side-chains or polymers. This allows nanocarbons to form a solvent-free, nonvolatile, room-temperature, high-viscosity liquid state. Herein, I describe the novel liquid nanocarbon science, how to liquefy nanocarbons by chemical functionalization, their bulk-state function, and self-assembly phenomena and also introduce their future potential applications.
Keywords: Room-Temperature Liquid / Fullerene / Carbon Nanotube / Graphene / Carbon Quantum Dots / Alkyl-π Engineering / Self-Assembly
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COVER STORY: Topics and Products
Carbon Materials Retaining the Structures of Precursor Organic Crystals Hirotomo NISHIHARA
<Abstract> One of the recent challenging targets in the field of carbon materials is the synthesis of well-organized nanocarbons and carbon-based materials by chemically sophisticated techniques. In this context, carbonization of organic-based crystalline solids such as metal-organic frameworks and organic crystals has been intensively investigated to date. However, organic-based crystals are always converted into intrinsically amorphous carbonaceous frameworks, and the structural regularity, as well as the major molecular features of the precursors, is totally lost by carbonization. We have recently demonstrated the successful conversion of organic crystals into carbonaceous frameworks that inherit the ordered structure as well as the molecular fragments of the original crystals. The resulting ordered carbonaceous frameworks exhibit an intermediate structure, between an organic-based framework and carbon material, with advantages from both structures.
Keywords: Metal-Organic Frameworks / Covalent-Organic Frameworks / Porous Carbons / Carbon Alloys
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Graphdiyne: 2D Carbon Created by Polymer Synthesis Ryota SAKAMOTO, Hiroshi NISHIHARA
<Abstract> The nanosheet is a 2D matter, the thickness of which reaches less than 1 nm. In addition to inorganic nanosheets like graphene and transition metal dichalcogenides, recent progress in synthetic and analytical chemistry allows researcher to create molecule-based nanosheets. This article reviews graphdiyne, a kind of 2D allotrope of graphene, which belongs to both inorganic and molecule-based nanosheet series.
Keywords: Graphdiyne / Interfacial Synthesis / 2D Carbon / Nanocarbon / Molecule-Based Nanosheet
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Sputtered Nanocarbon Film Electrodes Capable of Controlling sp2/sp3 Ratio Dai KATO, Osamu NIWA
<Abstract> This topic introduces our developed sputtered nanocarbon film electrodes and their applications to sensing platforms for trace amounts of various analytes. We have been studying nanocarbon film electrodes formed by an electron cyclotron resonance sputtering or an unbalanced magnetron sputtering method. The film provides a nanocrystalline sp2 and sp3 mixed bond structure with an atomically flat surface (surface roughness of 0.1 nm) and high conductivity without doping. The film electrode has excellent properties including a low background current, a wide electrochemical potential window, and little surface fouling, while maintaining relatively high electrode activity. These characteristics allow the detection of various analytes, especially ultratrace amounts of biomolecules. For example, the nanocarbon film electrode can quantitatively measure all the DNA bases and cerebral gliotransmitter, which are difficult to measure at conventional carbon electrodes.
Keywords: Sputtering / Nanocarbon Film / sp2/sp3 / Electroanalysis / Biosensing
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Fluidized-Bed Production and Battery Application of Long Carbon Nanotubes Suguru NODA
<Abstract> Carbon nanotubes (CNTs) are attracting much attention owing to its unique 1D nanostructure and properties. CNTs can be synthesized by various methods, and the characteristics of their production methods and resulting structures are introduced. Rapid, millimeter-scale growth of CNTs on 2D substrates has been established, and such CNTs can now be produced in 3D by fluidized-bed chemical vapor deposition using spherical ceramic beads. Acetylene is converted to 99 wt%-pure, sub-millimeter-long, few-wall CNTs efficiently at 70% yield in 0.3 s residence time. Self-supporting, sponge-like papers can be easily fabricated by dispersion and filtration, which work as light-weight, 3D current collectors for rechargeable batteries. A full lithium ion cell of LiCoO2-1 wt% CNT cathode and graphite-1 wt% CNT anode is developed without using metallic foils nor polymer binder. CNTs have rich varieties in their structure and production methods. They can be regarded as polymer made of only carbon, and will have rich opportunities for practical applications.
Keywords: Carbon Nanotubes / Chemical Vapor Deposition / Fluidized Bed / Battery
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Polymer Science and I: A Personal Account
My Heroes Daisuke SUZUKI
<Abstract> My research experiences benefitting by learning from my heroes is described. I do research enjoying both independent action and working as a team with collaborators. As successful as this is I hope that also the next 10 years will be such a fruitful research life.
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Front-Line Polymer Science
States of Water Molecules at the Biointerface – What is the Roles of Intermediate Water ? Masaru TANAKA
<Abstract> When the biomaterials come into contact with the biological fluids, water molecules immediately adsorb onto the surface of the materials. To understand the origin of the crucial roles of water molecules in biological interfaces, it is necessary to relate particular stats of hydration water to various physicochemical properties of hydrated polymers. Here, advances of intermediate water concept are reviewed. This paper provides an overview of the progress made in the design of multi-functional biomedical polymers by controlling the bio-interfacial water states.
Keywords: Water / Biomaterial / Surface / Interface / Biointerface / Cell Adhesion / Cold Crystallization / Intermediate Water
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