A5067502323- Advanced Polymer Synthesis and Characterization
- Material Dynamics and Properties
- Polymer crystallization and properties
- Block Copolymer Self-Assembly
- Force Microscopy Techniques and Applications
- Spectroscopy and Quantum Chemical Studies
- Polymer Nanocomposites and Properties
- Polymer Surface Interaction Studies
- Photochemistry and Electron Transfer Studies
- Synthesis and properties of polymers
- Hepatocellular Carcinoma Treatment and Prognosis
- Surfactants and Colloidal Systems
- RNA and protein synthesis mechanisms
- Conducting polymers and applications
- Material Properties and Processing
- Surface Modification and Superhydrophobicity
- Fuel Cells and Related Materials
- Rheology and Fluid Dynamics Studies
- Silicone and Siloxane Chemistry
- Electrostatics and Colloid Interactions
- Organic Electronics and Photovoltaics
- Integrated Circuits and Semiconductor Failure Analysis
- biodegradable polymer synthesis and properties
- Laser Material Processing Techniques
- Advanced Surface Polishing Techniques
The University of Tokyo
2023-2025
Nagoya University
2010-2025
Hitachi (United States)
2025
Kyushu University
2015-2024
Hamamatsu Photonics (Japan)
2017-2024
Saitama University
2021-2024
Interface (United States)
2023
Interface (United Kingdom)
2021
Hamamatsu Photonics (United Kingdom)
2017-2020
Public Works Research Institute
2020
The melt rheology of highly-purified ring polystyrenes in a wide range molecular weights (10K ≤ Mw 240K g/mol) was investigated. All the rings revealed no obvious rubbery plateau and faster terminal relaxation compared to linear counterparts. rheological data obtained were with some theoretical models such as Rouse model lattice-animal model. Moreover, two parameters, zero-shear viscosities η0 steady-state recoverable compliances Je, estimated, their dependence discussed. From these...
Starting with the clinical application of two vaccines in 2020, mRNA therapeutics are currently being investigated for a variety applications. Removing immunogenic uncapped from transcribed is critical research and Commonly used capping methods provide maximum efficiency around 80-90% widely Cap-0- Cap-1-type mRNAs. However, capped possesses almost identical physicochemical properties, posing challenges to their physical separation. In this work, we develop hydrophobic photocaged...
Ring polystyrenes (PSs) were synthesized by anionic polymerization technique and purified with preparative size-exclusion chromatography (SEC). Seven ring PSs their weight-average molecular weight (Mw) ranging from 17k to 570k prepared they confirmed have high purities all over 96% liquid at the chromatographic critical condition (LCCC) analyses. Their radii of gyration (Rgs) determined in benzene-d6 as a good solvent cyclohexane-d12 or cyclohexane-h12 Θ solvents small-angle neutron...
We report the structural relaxation process of irreversibly adsorbed polymer chains via thermal annealing that lie flat on a solid ("flattened chains"). Amorphous polystyrene and quartz, which together constitute weakly attractive system, was used as model where local chain conformations flattened were investigated by sum frequency generation spectroscopy (SFG). Two different film preparation processes (i.e., spin coating dip methods) utilized to create initial conformations. The spin-coated...
The relaxation dynamics of polyisoprene (PI) and nitrile butadiene rubber (NBR) chains at the SiO2 interface were directly probed as a function distance from surface using time-resolved evanescent wave-induced fluorescence anisotropy, dielectric spectroscopy, sum-frequency generation spectroscopy. We found presence gradient in interfacial region with tried to assign it two kinds adsorbed chains, namely, loosely strongly adsorbed, interface. segmental layer could be slower than that bulk by...
A better understanding of the aggregation states adhesive molecules in interfacial region with an adherend is crucial for controlling adhesion strength and great inherent academic interest. The mechanism has been described through four theories: adsorption, mechanical, diffusion, electronic. While characterization techniques have developed to validate aforementioned theories, that related electronic theory not yet thoroughly studied. We here directly detected interaction between a commonly...
Although many kinds of synthetic polymers have been investigated to construct blood-compatible materials, only a few achieved success. To establish molecular designs for polymers, the chain structure and dynamics at water interface must be understood using solid evidence as first bench mark. Here we show that polymer impacts on interfacial water, resulting in change protein adsorption platelet adhesion. As particular material, blend composed poly(2-methoxyethyl acrylate) (PMEA) poly(methyl...
The local conformation of poly(styrene-co-butadiene) rubber (SBR) chains in direct contact with a quartz substrate was examined by interface-sensitive sum-frequency generation (SFG) spectroscopy. SFG signals, which could be obtained from functional groups only oriented at the interface, were clearly observed for SBR film room temperature much higher than bulk glass transition (Tg). When thermally annealed, interface changed their to one lower energy state, accompanied randomization both main...
The performance of a polymer composite material, in which inorganic fillers are dispersed, is closely related to the aggregation states and dynamics chains at interface with filler. In this study, local conformation polyisoprene (PI) quartz substrate was studied as model system for rubber/filler material. PI films were prepared from toluene solution onto substrates by spin-coating method. Sum-frequency generation spectroscopy revealed that depended on spinning rate. tilt angle methyl groups...
The local conformation of polystyrene (PS) and deuterated PS at the interface with quartz substrates, which were covered phenyl groups using phenyltrimethoxysilane (PTS) under various conditions, was examined by sum frequency generation spectroscopy. As evidenced red-shift wavenumber v2 vibration mode for groups, it claimed that PTS standing vertically from surface induced perpendicular orientation rings energetically favorable parallel-displaced π–π interactions interface. chains strongly...
Abstract Messenger RNAs (mRNAs) with phosphorothioate modification (PS‐mRNA) to the phosphate site of A, G, C, and U all 16 possible combinations were prepared, translation reaction was evaluated using an E. coli cell‐free system. Protein synthesis from PS‐mRNA increased in 12 15 patterns when compared that unmodified mRNA. The protein yield 22‐fold at A/C sites introduced into region 5′‐end initiation codon. Single‐turnover analysis showed increases number translating ribosomes, thus...
The adsorbed layer on a solid surface plays crucial role in the dynamics of nanoconfinement polymer materials. However, influence is complex, and clarifying this confined polymers remains major challenge. In paper, SiO2-Si substrates with various thicknesses layers PS molecular weights were used to reveal effect corresponding segmental supported thin films. Strongly suppressed films observed for thicker or prepared using higher weight. Neutron reflectivity revealed that overlap region...
Site-specific chemical modification of mRNA can improve its translational efficiency and stability. For this purpose, it is desirable to develop a complete synthesis method for chemically modified mRNA. The key reaction that introduces cap structure into the synthesized RNA. In study, we developed fast quantitative capping between 5′-phosphorylated RNA N7-methylated GDP imidazolide in presence 1-methylimidazole organic solvent dimethyl sulfoxide. It enabled preparation within 3 h. We...
Surface mobility in polystyrene (PS) films was studied using (PS/deuterated PS) bilayer films, which were prepared by attaching original two surfaces together. Time evolution of the interface at various temperatures examined dynamic secondary ion mass spectroscopy conjunction with neutron reflectivity. When annealed a temperature above bulk glass transition temperature, Tgb, interfacial thickening well expressed context Fickian diffusion. On other hand, case an annealing surface Tgs, and...
Cyclization reaction product synthesized by the end-to-end ring closure of a telechelic polystyrene with molecular weight 38K in extremely dilute conditions was carefully characterized using two kinds HPLC techniques, that is, liquid chromatography at critical condition (LCCC) and size exclusion (SEC). First, cyclization coarsely separated into linear species cyclic ones LCCC; second, each fraction further high-resolution SEC. It found from analyses contains both condensation products....
ADVERTISEMENT RETURN TO ISSUEPREVCommunication to the...Communication the EditorNEXTComparison of Interdiffusion Behavior between Cyclic and Linear Polystyrenes with High Molecular WeightsDaisuke Kawaguchi, Keisuke Masuoka, Atsushi Takano, Keiji Tanaka, Toshihiko Nagamura, Naoya Torikai, Robert M. Dalgliesh, Sean Langridge, Yushu MatsushitaView Author Information Department Applied Chemistry, Graduate School Engineering, Nagoya University, Furo-cho, Chikusa-ku, 464-8603, Japan; Faculty...
The nature of the polymer-water interface in poly(methyl 2-propenyl ether) (PMPE)-water model system is investigated by sum-frequency generation spectroscopy, which at moment gives best depth resolution among available techniques. PMPE, synthesized via living cationic polymerization, structurally similar to methacrylate) (PMMA) except for lacking a carbonyl group. We here probe polymer local conformation as well aggregation states water interface. Comparing results our measurements...
Water sorption kinetics in thin Nafion films prepared on silver and silicon oxide substrates was examined by surface plasmon resonance neutron reflectivity measurements. It found that the thickened three regimes. The asymptotic swelling ratios regimes I, II, III were 1.05, 1.26, 1.41, respectively. These values independent of substrate species coincident with transition points different hydration states bulk Nafion; water binding to sulfonic acid groups, formation sphere-like ionic clusters,...
Thin amorphous poly(ethylene terephthalate) (PET) films covered with/without a crystallized surface layer were prepared onto silicon wafers. In the former and latter cases, mobility in film was depressed enhanced, respectively. The glass transition temperature (Tg) of PET decreased with reduction thickness, exhibiting remarkable nanoconfinement effect. However, once region thin crystallized, or frozen terms segmental motion, Tg recovered to that bulk. Concurrently, apparent activation energy...
Poly(2-methoxyethyl acrylate) (PMEA) segregation to the water interface in a blend film disturbed network structure of molecules, resulting effective suppression platelet adhesion.