受賞国：日本国

受賞国：日本国

受賞区分：学会誌・学術雑誌による顕彰  受賞国：日本国

受賞国：日本国

受賞区分：国内外の国際的学術賞  受賞国：デンマーク王国

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Chemical Physics  

Reverse nonequilibrium molecular dynamics (RNEMD) simulations impose a flux by swapping the velocities of two particles. This method allows for the calculation of transport coefficients, such as thermal conductivity and viscosity. The relation between the induced fluxes and the control parameters of RNEMD (such as the time interval between successive swap events) is not clear. Thus, trial-and-error is required to realize the desired fluxes in RNEMD simulations. In this study, we develop a theoretical framework using extreme value statistics to estimate the relation between the time interval and the resulting induced fluxes. Our RNEMD simulations, conducted with varying time intervals, confirm that the theoretical predictions are quantitatively consistent with the simulation results when the time interval exceeds the momentum relaxation time. Our RNEMD simulations also show that our theoretical predictions, which are valid for a large number of particles for swap candidates, work well even for a relatively small number of particles for swap candidates. These findings demonstrate that the induced fluxes can be reliably estimated, providing a valuable tool for selecting appropriate RNEMD parameters for simulations.

DOI： 10.1063/5.0236799

Web of Science

Scopus

PubMed

researchmap

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Polymer Journal  

According to a recent simulation study [Masubuchi et al., Macromolecules, 56, 9359 (2023)], the cycle rank plays a significant role in determining the fracture characteristics of network polymers. However, the previous studies considered only energy-minimized networks without including the effects of thermal agitation. To address this gap, this study conducted Brownian dynamics simulations at various stretch rates. The results showed that even with Brownian motion, the strain and stress at break obtained for different node functionalities and conversion ratios exhibited master curves when plotted versus the cycle rank. These master curves depend on the strain rate, indicating that the strain and stress at break decrease with decreasing strain rate. The curves are qualitatively similar to those observed in energy-minimized simulations, even though the competition among Brownian motion, elongation, and bond scission affects the fracture process.

DOI： 10.1038/s41428-024-00992-9

Web of Science

Scopus

researchmap

担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Chemical Theory and Computation  

Although the reverse nonequilibrium molecular dynamics (RNEMD) simulation method has been widely employed, the range of applicability is yet to be discussed. In this study, for the first time, we systematically examine the method against an unentangled melt of the Kremer-Grest type chain. The simulation results indicate that as the shear rate increases, the temperature and density become inhomogeneous. However, the average viscosity remains consistent with the results obtained using the SLLOD method under homogeneous temperature and density. We also confirm that the temperature-density inhomogeneity does not significantly affect polymer conformation.

DOI： 10.1021/acs.jctc.4c01007

Web of Science

Scopus

PubMed

researchmap

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Soft Matter  

Despite many attempts, the relationship between the fracture and structure of polymer networks is yet to be clarified. For this problem, a recent study on phantom chain simulations [Y. Masubuchi et al., Macromolecules, 2023, 56, 9359-9367.] has demonstrated that the fracture characteristics obtained for polymer networks with various node functionalities and conversion ratios lie on master curves if they are plotted against cycle rank, which is the number of closed loops in the network per network node. In this study, we extended the simulation to the effect of prepolymer concentration c on the relationships between the cycle rank and fracture characteristics within the concentration range of 1 ≲ c/c* ≲ 10, concerning the overlapping concentration c*. We created networks from sols of star-branched phantom bead-spring chains via an end-linking reaction between different chains through Brownian dynamics simulations upon varying the number of branching arms f from 1 to 8, and the conversion ratio φc from 0.6 to 0.95. For the resultant networks, the cycle rank ξ was consistent with the mean-field theory. The networks were uniaxially stretched with energy minimization until break to obtain modulus G, strain at break ϵb, stress at break σb, and work for fracture Wb. As reported earlier, ϵb data for various f and φc are located on a master curve if plotted against ξ. The other quantities also draw master curves as functions of ξ if normalized by the branch point density υbr. The master curves depend on c; as c increases, all the mechanical characteristics monotonically increase. If we plot σb/υbr and Wb/υbr against G/υbr, the data for various f and φc lie on master curves but depending on c. Consequently, the fracture characteristics are not solely described by the modulus.

DOI： 10.1039/d4sm00726c

Web of Science

Scopus

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Gels  

Recently, cellulose and other biomass nanofibers (NFs) have been increasingly utilized in the design of sustainable materials for environmental, biomedical, and other applications. However, the past literature lacks a comparison of the macromolecular and nanofibrous states of biopolymers in various materials, and the advantages and limitations of using nanofibers (NF) instead of conventional polymers are poorly understood. To address this question, hydrogels based on interpolyelectrolyte complexes (IPECs) between carboxymethyl cellulose nanofibers (CMCNFs) and chitosan (CS) were prepared by ele+ctrostatic cross-linking and compared with the hydrogels of carboxymethyl cellulose (CMC) and CS biopolymers. The presence of the rigid CMCNF altered the mechanism of the IPEC assembly and drastically affected the structure of IPEC hydrogels. The swelling ratios of CMCNF-CS hydrogels of ca. 40% were notably lower than the ca. 100–300% swelling of CMC-CS hydrogels. The rheological measurements revealed a higher storage modulus ((Formula presented.)) of the CMCNF-CS hydrogel, reaching 13.3 kPa compared to only 3.5 kPa measured for the CMC-CS hydrogel. Further comparison of the adsorption characteristics of the CMCNF-CS and CMC-CS hydrogels toward Cu2+, Cd2+, and Hg2+ ions showed the slightly higher adsorption capacity of CMC-CS for Cu2+ but similar adsorption capacities for Cd2+ and Hg2+. The adsorption kinetics obeyed the pseudo-second-order adsorption model in both cases. Overall, while the replacement of CMC with CMCNF in hydrogel does not significantly affect the performance of such systems as adsorbents, CMCNF imparts IPEC hydrogel with higher stiffness and a frequency-independent loss ((Formula presented.)) modulus and suppresses the hydrogel swelling, so can be beneficial in practical applications that require stable performance under various dynamic conditions.

DOI： 10.3390/gels10090604

Scopus

担当区分：最終著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Polymer Journal  

Recently, we developed an oxidative aging simulation technique that explicitly considers the transport of radicals by combining oxidation kinetics with coarse-grained molecular dynamics [1]. The current study explores the role of the free radical diffusivity of oxidative aging in polymers, with a focus on its effects on the heterogeneity of spatiotemporal structures and reaction kinetics, through coarse-grained simulations. By examining two distinct systems, including a heterosystem with a high reaction rate and a quasi-homosystem with a low reaction rate, we investigated how the diffusivity of free radicals influences the oxidative aging process. We examined three different diffusivity levels of radicals. For the slowest case, the radical diffusivity is slightly faster than that of the single polymer segment, whereas for the fastest case, the radical diffuses infinitely faster than the polymers. The aging simulations revealed that the variations in free radical diffusivity quantitatively change the reaction kinetics and spatiotemporal structures without qualitatively altering the overall aging behavior. Specifically, in a heterosystem, lower radical diffusivity slows the oxidation kinetics by increasing fluctuations in the local conversion ratios. In contrast, in a quasi-homosystem, reduced radical diffusivity slightly amplifies the heterogeneity of structures in the early aging stages; however, in a high-conversion region, the aged state becomes homogeneous regardless of the degree of radical diffusivity.

DOI： 10.1038/s41428-024-00942-5

Web of Science

Scopus

researchmap

その他リンク： https://www.nature.com/articles/s41428-024-00942-5

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Polymers  

A few experiments have reported that the time development of shear stress under fast-startup shear deformations exhibits double peaks before reaching a steady state for bimodal blends of entangled linear polymers under specific conditions. To understand this phenomenon, multi-chain slip-link simulations, based on the primitive chain network model, were conducted on the literature data of a bimodal polystyrene solution. Owing to reasonable agreement between their data and our simulation results, the stress was decomposed into contributions from long- and short-chain components and decoupled into segment number, stretch, and orientation. The analysis revealed that the first and second peaks correspond to the short-chain orientation and the long-chain stretch, respectively. The results also implied that the peak positions are not affected by the mixing of short and long chains, although the intensity of the second peak depends on mixing conditions in a complicated manner.

DOI： 10.3390/polym16111455

Scopus

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Macromolecules  

Slip-spring models are valuable tools for simulating entangled polymers, bridging the gap between bead-spring models with excluded volume and network models with presumed reptation motion. This study focuses on the DPD-SS (Dissipative Particle Dynamics-Slip-Spring) model, which introduces slip springs into the standard DPD polymer model with soft-core interactions. By systematically adjusting the activity of slip springs, the density of slip springs within the system is varied. Simulation results demonstrate the compatibility of models with different slip-spring densities in terms of diffusion and linear relaxation modulus when the average number of slip springs per chain is the same. The conversion between DPD-SS models concerning length and time is achieved through Rouse scaling, which utilizes the average number of DPD beads between consecutive anchoring points of slip springs. Additionally, the modulus conversion is accomplished through the plateau modulus that takes account of fluctuations around entanglement. Notably, diffusion and relaxation modulus from the DPD-SS model align with those reported for standard Kremer-Grest and DPD models featuring strong repulsive interactions.

DOI： 10.1021/acs.macromol.4c00280

Web of Science

Scopus

researchmap

担当区分：最終著者,　責任著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Nihon Reoroji Gakkaishi  

We investigated the effect of surface treatment for iron particles in the magnetorheological fluids (MRFs) on rheological properties. Silane coupling treatment with an excess amount of dodecyltrimethoxysilane (DTMS) was conducted for iron particles. MRFs were prepared by dispersing iron particles with and without the silane coupling treatment. MRFs with iron particles washed with n-hexane after the silane coupling treatment was also prepared. The rheological properties of MRFs were measured in the presence and absence of a magnetic field. Without a magnetic field, MRFs with the silanecoupled particles exhibited higher stress than the untreated particles. Under a magnetic field, MRFs with the silane-coupled particles showed lower stress than the untreated analogue. These results imply that the silane coupling treatment enhances the aggregation of particles without a magnetic field but suppresses the cluster formation under the magnetic field. MRFs with the washed iron particles exhibited almost the same rheological properties as that with the untreated particles. Thus we suggest that DTMS is mainly physically absorbed on the surface of iron particles, without forming chemical bonds.

DOI： 10.1678/rheology.52.99

Scopus

CiNii Research

researchmap

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Nihon Reoroji Gakkaishi  

Anisotropic shear relaxation is an interesting but rarely discussed issue in polymer dynamics under confinement. According to the earlier study of bead spring simulations for an unentangled polymer melt confined between two flat plates, the shear relaxation modulus taken perpendicular to the interface is accelerated by decreasing the distance between plates, whereas the parallel component is unchanged [Abberton et al., Macromolecules, 48, 7631, 2015]. This study observed similar anisotropic shear relaxation for entangled polymer melts under confinement in multi-chain slip-link simulations (primitive chain network simulations) for shear relaxation moduli obtained by the Green-Kubo formula. The analysis demonstrated that the accelerated relaxation in the perpendicular component reflects the Rouse-type constraint release dynamics, for which the coarsening is upper-limited by the geometry. This result suggests a novel mechanism for anisotropic shear relaxation different from the modified chain statistics under confinement considered for unentangled systems unless the obtained relaxation moduli reflect artifacts from the use of the Green-Kubo formula under confinement.

DOI： 10.1678/RHEOLOGY.52.77

Scopus

CiNii Research

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.polymer.2024.126880

researchmap

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1678/rheology.52.21

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Polymer Journal  

Fujiyabu et al. [1] experimentally reported that mixing of 3-arm star prepolymers into 4-arm analogs improves the toughness of the resultant polymer networks compared to that of the base network composed of only 4-arm star polymers. The present study investigated the mechanism of this phenomenon based on phantom chain simulations for polymer networks consisting of mixtures of star branch prepolymers with equal arm length and different arm numbers, (f1,f2)=(3, 4) , (3, 6) and (3, 8) , for various f1= 3 prepolymer fractions φ3 . These networks were created via end-linking reactions between prepolymers traced by a Brownian dynamics scheme, and the network structure was stored at different conversion ratios φc , ranging from 0.6 to 0.9. The cycle rank of the gelated networks ξ is entirely consistent with that given by mean-field theory, demonstrating that the examined network structure is statistically valid. The networks were stretched with energy minimization until the break, and fracture characteristics including strain at break εb , stress at break σb , work for fracture Wb , and the ratio of broken strands φbb , were obtained. Plots of εb , σb/ φbb , and Wb/ φbb versus ξ roughly follow the master curves reported for the base networks without mixing, implying that the change of fracture properties by the mixing of f1= 3 mainly corresponds to a decrease in ξ . The mixing slightly suppresses σb/ φbb and Wb/ φbb for large f2 cases compared to the base networks because of a biased breakage at the network strands without extenders, which are prepolymers with only two reacted arms. The analysis also revealed a new master curve for the ξ -dependence of the molecular weight of broken strands.

DOI： 10.1038/s41428-023-00862-w

Scopus

担当区分：最終著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Macromolecules  

This study presents a coarse-grained molecular dynamics simulation model to investigate the process of oxidative aging in polymers. The chemical aging effect is attributed to the autoxidation mechanism, which is initiated by radicals, leading to the chain scission and cross-linking of polymer chains. In this study, we integrate a thermal oxidation kinetic model in the oxygen excess regime into the Kremer-Grest model, thereby enabling a reactive coarse-grained molecular dynamics simulation to capture the process of oxidative degradation. Our simulation reveals that when the time scale of the characteristic reaction step of oxidative degradation is shorter than the longest relaxation time of polymer chains, the scission sites exhibit spatial heterogeneity. This innovative simulation model possesses the potential to enhance our comprehension of polymer aging phenomena, thus making noteworthy contributions to the realm of polymer science and degradation chemistry.

DOI： 10.1021/acs.macromol.3c01708

Scopus

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Molecular Simulation  

In some binary fluids, mass transport is observed under a temperature gradient. This phenomenon is called the Soret effect. In this study, we discuss the influence of inter-particle interaction. We considered equimolar binary Lennard–Jones fluids with a mass contrast, whereas the interaction was common for all the particle pairs with various cut-off lengths. We performed molecular dynamics simulations of such fluids under equilibrium to obtain the cross-transport coefficients (Formula presented.) between the fluxes of mass and heat. The simulation revealed that this quantity strongly depends on the cut-off length. Further, we decomposed the heat flux into kinetic and potential contributions and calculated the cross-correlations between decomposed fluxes and the mass flux. The result indicates that the potential contribution dominates (Formula presented.), implying that the Soret coefficient is altered by the inter-particle interaction.

DOI： 10.1080/08927022.2023.2268730

Web of Science

Scopus

researchmap

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Nihon Reoroji Gakkaishi  

In the multi-chain slip-spring, the dynamics of Rouse chains connected by virtual springs called slip-springs that hop along the chain are considered. Although this approach has been proven to reproduce entangled polymer dynamics efficiently, the settings of the artificially introduced slip-springs should be carefully examined. In this study, we discussed the effect of the slip-spring degeneracy by limiting the number of anchored slip-springs on each Rouse bead to zero and one. According to the altered slip-spring statistics, we derived the compensation potential to eliminate the artifact of slip-springs on the chain statistics. With this potential, we performed numerical simulations. The results demonstrated that although we reasonably retain the Gaussian chain statistics, the dynamics deviate from the established entangled polymer dynamics because of the significant slow-down in the chain motion induced by the correlation between different slip-springs. The observed deceleration can be explained by the fact that the movement of slip-springs can be cast into an asymmetric exclusion process.

DOI： 10.1678/rheology.51.211

Web of Science

Scopus

CiNii Research

researchmap

担当区分：最終著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：International Journal for Numerical Methods in Fluids  

We develop a novel Moving Particle Simulation (MPS) method to reproduce the motion of fibers floating in sheared liquids accurately. In conventional MPS schemes, if a fiber suspended in a liquid is represented by a one-dimensional array of MPS particles, it is entirely aligned to the flow direction due to the lack of shear stress difference between fiber–liquid interfaces. To address this problem, we employ the micropolar fluid model to introduce rotational degrees of freedom into the MPS particles. The translational motion of liquid and solid particles and the rotation of solid particles are calculated with the explicit MPS algorithm. The fiber is modeled as an array of micropolar fluid particles bonded with stretching, bending and torsional potentials. The motion of a single rigid fiber is simulated in a three-dimensional shear flow generated between two moving solid walls. We show that the proposed method is capable of reproducing the fiber motion predicted by Jeffery's theory which is different from the conventional MPS simulations.

DOI： 10.1002/fld.5235

Scopus

researchmap

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.macromol.3c01291

Web of Science

researchmap

担当区分：最終著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Polymer Journal  

Two-dimensional sheet-shaped poly(methyl methacrylate) (2d-PMMA) with crosslinking only in the two-dimensional direction was synthesized via planar polymerization of MMA monomer in montmorillonite (MMT) nanolayers by using γ-ray irradiation, and the samples obtained were characterized. Size-exclusion chromatography with a multi-angle light scattering (SEC-MALS) measurements of the obtained sample showed bimodal peaks: a main peak with a longer elution time and an apparent molecular weight M w,app and radius of gyration R g in tetrahydrofuran (THF) similar to those for linear PMMA samples, and a subpeak with a shorter elution time and M w,app and R g evidently lower than those for the linear PMMA samples. This result indicated that polymers with moderate branching and crosslinking were contained in the subpeak. Atomic force microscopy (AFM) observation of the sample showed the presence of sheet-shaped molecules with a height of ca. 0.6 nm, corresponding to the thickness of one MMA monomer, and a width of several to several tens of nanometers, showing a broad distribution in molecular width. The subpeak portion was isolated via SEC fractionation, and its AFM observation showed thin circular disk-shaped molecules with relatively uniform size (i.e., a width of several tens of nanometers). However, in these molecules, two types of molecular heights (i.e., 0.6 and 1.2 nm) were identified. This result indicated that MMA monomers were filled as two layers within one MMT interlayer, and the polymerization reaction proceeded in that state. The similarity in the molecular size of 2d-PMMA observed via AFM and SEC-MALS was confirmed. These results demonstrated that the desired sheet-shaped polymers were obtained through the above synthesis and fractionation process.

DOI： 10.1038/s41428-023-00795-4

Scopus

researchmap

その他リンク： https://www.nature.com/articles/s41428-023-00795-4

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Non-Newtonian Fluid Mechanics  

We revisit the transient response of entangled polymers in shear startup. Evidence from state-of-the-art experiments, modeling and simulations suggests the presence in fast flows of a weak (albeit unambiguous) undershoot, following the overshoot, i.e., while approaching the steady state. Recent sliplink simulations confirmed that the undershoot is not due to slip at the wall, and hence it is intrinsic to polymer rheology. Here, we further examine some features of the undershoot by blending two entangled homopolymers at different compositions. Since blending affects the distribution of relaxation times, it is here shown to also affect the undershoot, probably by broadening the tumbling-time distribution. Indeed, by appropriately modifying our tube-based model, that invokes tumbling to account for the undershoot, and (in parallel) by using simulations, we show how the undershoot depends on the blend composition. We map the experimental results into a diagram of terminal relaxation time versus composition, which identifies regimes where the undershoot is present. Blending is therefore proposed as a molecular mechanism to tailor the shear stress growth function signal, particularly the undershoot.

DOI： 10.1016/j.jnnfm.2023.105028

Web of Science

Scopus

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Non-Newtonian Fluid Mechanics  

Description of the elongational rheology of concentrated polymers appears to require that in fast flows the friction coefficient decreases with respect to its equilibrium value. However, the proposed models typically maintain the validity of the fluctuation-dissipation theorem (FDT) out of equilibrium. On the other hand, FDT is routed in local equilibrium, the latter being clearly violated by the flow-induced monomer coalignment that induces friction change. A recent analysis by Watanabe et al. [Macromolecules, 54, 3700 (2021)] of unentangled polystyrene (PS) melts, based on a nonlinear extension of the Rouse model, indicates that FDT is indeed violated in fast flows. According to their analysis, the Brownian force intensity remains almost independent of the flow rate, even though the friction coefficient drastically decreases. A different violation of FDT is shown by previous nonequilibrium molecular dynamics simulations of PS oligomers [Ianniruberto et al., Macromolecules, 45, 8058 (2012)] where the diffusion coefficient grows more than the inverse friction coefficient. In this paper, Brownian simulations using a multi-chain sliplink model (the so-called primitive chain network model) are reported for two monodisperse entangled PS melts, for which nonlinear shear and elongational data were published. Two different friction reduction models are examined, and the effect of switching FDT on and off is tested. Results demonstrate that, irrespective of FDT, both friction models can reasonably well reproduce the behavior shown by the data. This result lends support to models that retain FDT since its violation appears not to significantly affect predictions of nonlinear rheology.

DOI： 10.1016/j.jnnfm.2023.105019

Web of Science

Scopus

担当区分：最終著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Physical Review E  

Rod-shaped particles embedded in certain matrices have been reported to exhibit an increase in their center of mass diffusivity upon increasing the matrix density. This increase has been considered to be caused by a kinetic constraint in analogy with tube models. We investigate a mobile rodlike particle in a sea of immobile point obstacles using a kinetic Monte Carlo scheme equipped with a Markovian process, that generates gaslike collision statistics, so that such kinetic constraints do essentially not exist. Even in such a system, provided the particle's aspect ratio exceeds a threshold value of about 24, the unusual increase in the rod diffusivity emerges. This result implies that the kinetic constraint is not a necessary condition for the increase in the diffusivity.

DOI： 10.1103/PhysRevE.107.044604

Web of Science

Scopus

researchmap

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Macromolecules  

Effects of branch functionality on mechanical properties of polymer networks are yet to be fully elucidated, although multi-functional approaches have been mainly attempted. For instance, Fujiyabu et al. [Sci. Adv. 2022, 8, abk0010] recently reported that polymer networks made from tri-branch prepolymers exhibit superior mechanical properties to tetra-branch analogues. Although they attribute the difference to stretch-induced crystallization observed in tri-branch poly (ethylene glycol) networks, the mechanism still needs to be clarified. In this study, we performed coarse-grained molecular simulations to extract the effect of branch functionality. The prepolymers were replaced by bead-spring phantom chains, and gelation was simulated by a Brownian dynamics scheme. We subjected the resultant networks to energy minimization and uniaxial stretch by introducing breakage for elongated segments. In the stress-strain relation thus obtained, stress and strain at the break were larger for tri-branch networks than that for tetra-branch analogues, consistent with the experiment. The superiority of tri-branch networks is observed in a wide range of the conversion ratio in gelation, molecular weights of prepolymers, and polymer concentrations. The result implies that the mechanical superiority of tri-branch networks to tetra-branch ones is due to a fundamental structural difference generated during gelation.

DOI： 10.1021/acs.macromol.3c00047

Web of Science

Scopus

researchmap

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：The Society of Rheology, Japan  

<p>In the framework of the tube model, the survival fraction of dilated tube, φʹ(<i>t</i>), is essential since the relaxation of the entire system is described according to this quantity. However, a method to define it in multi-chain simulations has yet to be considered. In this study, primitive chain network simulations were performed, and a few structural quantities were discussed as possible candidates for use as φʹ(<i>t</i>). Before analysis, the simulation was evaluated against literature data for linear polyisoprene melts, and quantitative agreement was obtained for viscoelastic and dielectric relaxations. Afterward, the end-to-end relaxation function was compared to survival probability of the slip link φ_s(<i>t</i>) and the ratio of monomers between the most distant surviving slip link pair to the total number of monomers <i>n</i>_s(<i>t</i>)/<i>n</i>_t. The result implies that <i>n</i>_s(<i>t</i>)/<i>n</i>_t is comparable to φʹ(<i>t</i>). Comparison to atomistic molecular dynamics (MD) simulations for polyethylene showed similar results, implying that φʹ(<i>t</i>) can be obtained even in MD simulations if the surviving entanglement points can be specified.</p>

DOI： 10.1678/rheology.51.19

CiNii Research

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Physical Review E  

Diffusivity in some soft matter and biological systems changes with time, called the fluctuating diffusivity. In this work, we propose a novel origin for fluctuating diffusivity based on stochastic simulations of binary gas mixtures. In this system, the fraction of one component is significantly small, and the mass of the minor component molecule is different from that of the major component. The minor component exhibits fluctuating diffusivity when its mass is sufficiently smaller than that of the major component. We elucidate that this fluctuating diffusivity is caused by the time scale separation between the relaxation of the velocity direction and the speed of the minor component molecule.

DOI： 10.1103/PhysRevE.107.014605

Scopus

担当区分：最終著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Rheologica Acta  

In fast elongational flows, linear polymer melts exhibit a monotonic decrease of the viscosity with increasing strain rate, even beyond the contraction rate of the polymer defined by the Rouse time. We consider two possible explanations of this phenomenon: (a) the reduction of monomeric friction and (b) the reduction of the tube diameter with increasing deformation leading to an Enhanced Relaxation of Stretch (ERS) on smaller length scales. (Masubuchi et al. (2022) reported Primitive Chain Network (PCN) simulations using an empirical friction reduction model depending on segmental orientation and could reproduce the elongational viscosity data of three poly(propylene carbonate) melts and a polystyrene melt. Here, we show that the mesoscopic tube-based ESR model (Wagner and Narimissa 2021) provides quantitative agreement with the same data set based exclusively on the linear-viscoelastic characterization and the Rouse time. From the ERS model, a parameter-free universal relation of monomeric friction reduction as a function of segmental stretch can be derived. PCN simulations using this friction reduction relation are shown to reproduce quantitatively the experimental data even without any fitting parameter. The comparison with results of the earlier PCN simulation results with friction depending on segmental orientation demonstrates that the two friction relations examined work equally well which implies that the physical mechanisms of friction reduction are still open for discussion.

DOI： 10.1007/s00397-022-01373-w

Web of Science

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry Letters  

We report carbon nanotube (CNT) gels, formed by mechanically mixing CNTs, organic solvents, and a small molecule, Trip-Phz, that have a strong affinity for fullerene materials. There is a clear threshold value in the amount of Trip-Phz needed for the transition from soft to hard gels.

DOI： 10.1246/cl.220319

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Polymer Journal  

In this study, we examined the viscoelastic properties of a series of comb-shaped ring (RC) polystyrene samples with different branch chain lengths, i.e., the molecular weights of the ring backbone Mbb (≃ 4Me where Me is the entanglement molecular weight) and branch chains Mbr (≃ Me, 2Me, and 4Me). Even for the RC sample with the shortest branch chains, a plateau region was observed for the dynamic modulus G*(ω) in the middle angular frequency ω region, suggesting that intermolecular branch chain entanglement occurred. In the ω region between the plateau and terminal regions, G*(ω) was observed with a weaker ω dependence than the terminal relaxation. This behavior was more pronounced for RC samples with shorter branch chains and for the corresponding linear comb (LC) samples than for the RC ones. The molecular weight dependence of the zero-shear viscosity η0 and the steady-state recoverable compliance Jeo of the RC and LC samples was evaluated, and the effects of different backbone molecular structures (i.e., ring or linear) on the terminal relaxation behavior was discussed. Moreover, the G*(ω) data were analyzed with two models: the comb-Rouse model, in which the structures of the RC/LC molecules are taken into account by graph theory, and the Milner-McLeish model for entangled star-shaped polymers. The former model qualitatively described the terminal relaxation behavior of G*(ω) at low ω but failed to reproduce the plateau in the middle ω range. Conversely, the latter model described the entanglement plateau in the middle ω range, but the difference in the terminal relaxation regime for the RC/LC samples seen in the data and the comb-Rouse model disappeared.

DOI： 10.1038/s41428-022-00686-0

Scopus

担当区分：最終著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：The Society of Rheology, Japan  

<p>We derive the stress tensor of a rigid dumbbell by using the virtual work method. In the virtual work method, we virtually apply a small deformation to the system, and relate the change of the energy to the work done by the stress tensor. A rigid dumbbell consists of two particles connected by a rigid bond of which length is constant (the rigid constraint). The energy of the rigid dumbbell consists only on the kinetic energy. Also, only the deformations which do not violate the rigid constraint are allowed. Thus we need the dynamic equations which are consistent with the rigid constraint to apply the virtual deformation. We rewrite the dynamic equations for the underdamped SLLOD-type dynamic equations into the forms which are consistent with the rigid constraint. Then we apply the virtual deformation to a rigid dumbbell based on the obtained dynamic equations. We derive the stress tensor for the rigid dumbbell model from the change of the kinetic energy. Finally, we take the overdamped limit and derive the stress tensor and the dynamic equation for the overdamped rigid dumbbell. We show that the Green-Kubo type linear response formula can be reproduced by combining the stress tensor and the dynamic equation at the overdamped limit.</p>

DOI： 10.1678/rheology.50.313

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：The Society of Rheology, Japan  

<p>Although chemistry dependence in the non-linear rheology of polymers has been rather established for uniaxial elongations, it has not been frequently discussed for fast shear. In this study, to see the effect of orientation-dependent monomeric friction on the shear rheology, we conducted primitive chain network simulations for a few poly(propylene carbonate) melts, for which we have determined the friction model from the uniaxial data recently [Yang <i>et al.</i>, Nihon Reoroji Gakkaishi, 50, 127–135 (2022)]. The simulation qualitatively reproduced typical non-linear behaviors, such as shear thinning and stress overshoot, under fast shears. The agreement with experimental data became better when the friction was varied according to the segment orientation. In particular, the shear rate dependence of the peak position for the stress overshoot (<i>i.e.</i>, the peak stress and the strain at the peak) was better reproduced. This result implies that chemistry-dependent friction may probably be discussed from the stress overshoot under high shear.</p>

DOI： 10.1678/rheology.50.305

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Soft Matter  

We studied the effect of arm length contrast of prepolymers on the mechanical properties of tetra-branched networks via Brownian dynamics simulations. We employed a bead-spring model without the excluded volume interactions, and we did not consider the solvent explicitly. Each examined 4-arm star branch prepolymer has uneven arm lengths to attain two-against-two (2a2) or one-against-three (1a3) configurations. The arm length contrast was varied from 38-2 to 20-20 for 2a2, and from 5-25 to 65-5 for 1a3, with the fixed total bead number of 81, including the single bead located at the branch point for prepolymers. We distributed 400 molecules in the simulation box with periodic boundary conditions, and the bead number density was fixed at 4. We created polymer networks by cross-end-coupling of equilibrated tetra-branched prepolymers. To mimic the experiments of tetra gels, we discriminated the molecules into two types and allowed the reaction only between different types of molecules at their end beads. The final conversion ratio was more than 99%, at which unreacted dangling ends are negligible. We found that the fraction of double linkage, in which two of the four arms connect a pair of branch points, increases from 3% to 15% by increasing the arm length contrast. We stretched the resultant tetra-type networks to obtain the ratio of mechanically effective strands. We found that the ratio is 96% for the monodisperse system, decreasing to 90% for high arm length contrast. We introduced bond scission according to the bond stretching to observe the network fracture under sufficiently slow elongation. The fracture behavior was not correlated with the fraction of double linkage because the scission occurs at single linkages.

DOI： 10.1039/d2sm00488g

Web of Science

Scopus

researchmap

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Physical Chemistry B  

The multichain slip-spring (MCSS) model is one of the coarse-grained models of polymers developed in the niche between bead-spring models and tube type descriptions. In this model, polymers are represented by Rouse chains connected by virtual springs that temporally connect the chains, hop along the chain, and are constructed and annihilated at the chain ends. Earlier studies have shown that MCSS simulations can nicely reproduce entangled and unentangled polymer dynamics. However, the model parameters have been chosen arbitrarily, and their effects have not been reported. In this study, for the first time, we systematically investigated the effects of model parameters: fugacity of virtual springs, its intensity, and the Rouse bead density. We validated the employed simulation code by confirming that the statistics of the system follow the theoretical setup. Namely, the virtual spring density is correctly controlled, and polymer chains exhibit ideal chain statistics irrespective of the chosen parameter values. For diffusion and linear viscoelasticity, simulation results obtained for different parameters can be superposed with each other by conversion factors for the bead number per chain and units of length, time, and modulus. These conversion factors follow scaling laws concerning the number of Rouse segments between two consecutive anchoring points of virtual springs along the polymer chain. Besides, diffusion and viscoelasticity excellently agree with literature data for the standard bead-spring simulation. These results imply that the coarse-graining level for the MCSS model can be arbitrarily chosen and controlled by model parameters.

DOI： 10.1021/acs.jpcb.2c00697

Web of Science

Scopus

CiNii Research

researchmap

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Polymers  

It has been established that the elongational rheology of polymers depends on their chemistry. However, the analysis of experimental data has been reported for only a few polymers. In this study, we analyzed the elongational viscosity of poly (propylene carbonate) (PPC) melts in terms of monomeric friction via primitive chain network simulations. By incorporating a small polydispersity of materials, the linear viscoelastic response was semi-quantitatively reproduced. Owing to this agreement, we determined units of time and modulus to carry out elongational simulations. The simulation with constant monomeric friction overestimated elongational viscosity, whereas it nicely captured the experimental data if friction decreased with increasing segment orientation. To see the effect of chemistry, we also conducted the simulation for a polystyrene (PS) melt, which has a similar entanglement number per chain and a polydispersity index. The results imply that PPC and PS behave similarly in terms of the reduction of friction under fast deformations.

DOI： 10.3390/polym14040741

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Nihon Reoroji Gakkaishi  

Nonlinear shear and elongational rheology of entangled poly(propylene carbonate) (PPC) melts having different molecular weights with relatively narrow molecular weight distribution are examined. In shear measurements, the PPCs exhibit a typical shear thinning behavior with stress overshoot at high shear rates. In the shear rate dependence of the steadystate viscosity, the PPCs do not violate the empirical Cox-Merz rule, which is known to be valid for many other entangled polymer melts. In uniaxial elongational measurements, the viscosity growth functions of the PPCs show a weak deviation from the linear viscoelastic (LVE) envelope to the higher side at the high Weissenberg number Wid (= ͘ετd, where ͘ε is the elongation rate and τd is the characteristic disengagement time). The steady-state viscosity of the PPCs shows an elongational thinning as a function of ͘ε −0.5 within an error. These results are similar to some other polymer melts such as polystyrene (PS). In addition, the normalized elongational viscosity growth functions of PPC and PS with a similar entanglement number Z, are compared. The PPC exhibits a similar viscosity growth curve to the PS at the same Wid. This result suggests that the degree of the monomeric friction reduction originated from the stretch/orientation of PPC under fast elongational flow might occur at the same level as PS.

DOI： 10.1678/rheology.50.127

Scopus

担当区分：最終著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Rheologica Acta  

We synthesized model polyethylene (PE) samples with nearly monodispersed molecular weight distribution and different fractions of short-chain branches to investigate the influences of the branch structure on the rheological properties. The activation energy of the flow process showed linear relations with the weight fractions of comonomer and the short-chain branch. These results suggest that the friction of the chain motion is dominated by the amount of the short-chain branch. The zero-shear viscosity showed a power law to Mw with an exponent of about 3.3 for all linear and branched PEs. The branched PEs showed large entanglement molecular weights compared with the linear PEs because the introduction of the short-chain branches results in the increase of the average molecular weight per backbone unit. Moreover, the introduction of the short-chain branches has no influence on the strain-hardening under an extensional elongation process, indicating that the short-chain branches only affect the friction.

DOI： 10.1007/s00397-021-01286-0

Scopus

researchmap

その他リンク： https://link.springer.com/article/10.1007/s00397-021-01286-0/fulltext.html

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Rheology  

DOI： 10.1122/8.0000194

Scopus

担当区分：最終著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Chemical Physics  

DOI： 10.1063/5.0036555

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ACS Applied Bio Materials  

DOI： 10.1021/acsabm.0c01533

Scopus

担当区分：最終著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Macromolecules  

DOI： 10.1021/acs.macromol.0c01790

Scopus

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Nihon Reoroji Gakkaishi  

Although the entanglement network among polymers has been widely investigated, the spatial distribution of entanglement nodes has been rarely discussed. In this study, we obtained the radial distribution functions (RDFs) for the entanglement nodes from the snapshots of multi-chain slip-link simulations. The model employed in this study is the primitive chain network (PCN) model, which has been validated to reproduce the entangled polymer dynamics semi-quantitatively. The statistics of captured entanglement networks were compared to those reported for the primitive path network extracted by the CReTA procedure from the full-atomistic molecular model of a polyethylene melt. In the range of distance longer than the average strand length, the network structure from PCN does not show any structural correlation, and the intra-chain correlation is close to that for Gaussian chains with non-interacting slip-links. These features are consistent with the CReTA network and the conventional assumptions made for single-chain models. Meanwhile, in the short-range, the structural correlation in PCN is much weaker than that in CReTA. This discrepancy is because the short-range structure in PCN is realized as a result of imposed fluctuations, whereas it is determined by the minimization of the primitive path in CReTA.

DOI： 10.1678/rheology.49.337

Web of Science

Scopus

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Nihon Reoroji Gakkaishi  

Ianniruberto and Marrucci [Macromolecules, 46, 267-275, 2013] developed a theory whereby entangled branched polymers behave like linear ones in fast elongational flows. In order to test such prediction, Huang et al [Macromolecules, 49, 6694-6699, 2016] performed elongational measurements on star polymer melts, indeed revealing that, in fast flows, the elongational viscosity is insensitive to the molecular structure, provided the molecular weight of the "backbone" (spanning the largest end-to-end distance of the molecule) is the same. Inspired by these studies, we here report on results obtained with multi-chain sliplink simulations for symmetric and asymmetric star polymer melts, as well as calculations of the Rouse time of the examined branched structures (not previously determined by Ianniruberto and Marrucci). The simulations semi-quantitatively reproduce the experimental data if the Kuhn-segment orientation-induced reduction of friction (SORF) is accounted for. The observed insensitivity of the nonlinear elongational viscosity to the molecular structure for the same span molar mass may be due to several factors. In the symmetric case, the calculated Rouse time of the star marginally differs from that of the linear molecule, so that possible differences in the observed stress fall within the experimental uncertainty. Secondly, it is possible that flow-induced formation of hooked star pairs (or even larger aggregates) makes the effective Rouse time of the aggregate even closer to that of the linear polymer because the friction center moves towards the branchpoint of the star molecule. In the asymmetric case, it is shown that the stress contributed by the short arms is negligible with respect to that of the long ones. However, such stress reduction is balanced by a dilution effect whereby the unstretched arms reduce SORF as they decrease the Kuhn-segment order parameter of the system. As a result of that dilution, the stress contributed by the backbone is larger. The two effects compensate one another, so that the overall stress is virtually the same of the other architectures.

DOI： 10.1678/rheology.49.171

Scopus

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Nihon Reoroji Gakkaishi  

Primitive chain network simulations for randomly cross-linked slip-link networks were performed. For the percolated networks, the stress-strain relationship was compared to the theories by Ball et al. [Polymer, 22, 1010 (1981)] and Rubinstein and Panyukov [Macromolecules, 35, 6670 (2002)]. The simulation results are reasonably reproduced by both theories when the contributions from cross-links and slip-links are determined irrespective of the network structure. The fraction of slip-links contained in the network thus obtained is model dependent, and it does not coincide with the number of active slip-links in the actual networks. This discrepancy between the theories and the simulation results is due to the network inhomogeneity.

DOI： 10.1678/rheology.49.73

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：一般社団法人 日本レオロジー学会  

<p>The linear viscoelastic properties of poly(propylene carbonate) (PPC) melts having different molecular weights and narrow molecular weight distributions were studied. Some linear viscoelasticity parameters, including the plateau modulus and zero shear viscosity of PPC, were evaluated. The entanglement molecular weight of PPC was estimated to be 5.9 kg/mol, which is considerably lower than that previously reported for PPC with a broad molecular weight distribution.</p>

DOI： 10.1678/rheology.49.267

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.patter.2020.100135

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Physical Review E  

DOI： 10.1103/PhysRevE.102.032104

Web of Science

Scopus

researchmap

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Soft Matter  

DOI： 10.1039/d0sm00654h

Web of Science

Scopus

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Rheology  

DOI： 10.1122/8.0000046

Web of Science

Scopus

researchmap

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Soft Matter  

DOI： 10.1039/c9sm01971e

Web of Science

Scopus

researchmap

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Nihon Reoroji Gakkaishi  

DOI： 10.1678/rheology.48.37

Web of Science

Scopus

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Nihon Reoroji Gakkaishi  

DOI： 10.1678/rheology.48.43

Web of Science

Scopus

researchmap

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Korea Australia Rheology Journal  

DOI： 10.1007/s13367-019-0024-3

Web of Science

Scopus

researchmap

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/C9SM00681H

担当区分：最終著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Rheologica Acta  

DOI： 10.1007/s00397-019-01136-0

Web of Science

Scopus

researchmap

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/polym11020370

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ECS Transactions  

DOI： 10.1149/08801.0161ecst

Scopus

researchmap

担当区分：最終著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Nihon Reoroji Gakkaishi  

<p>The overdamped (inertialess) dumbbell model is widely utilized to study rheological properties of polymers or other soft matters. In most cases, the effect of inertia is merely neglected because the momentum relaxation is much faster than the bond relaxation. We theoretically analyze the effect of inertia on the linear viscoelasticity of the harmonic dumbbell model. We show that the momentum and bond relaxation modes are kinetically coupled and the inertia can affect the bond relaxation if the momentum relaxation is not sufficiently fast. We derive an overdamped Langevin equation for the dumbbell model, which incorporates the weak inertia effect. Our model predicts the bond relaxation dynamics with the weak inertia effect correctly. We discuss how the weak inertia affects the linear viscoelasticity of a simple harmonic dumbbell model and the Rouse model.</p>

DOI： 10.1678/rheology.47.143

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Macromolecules  

DOI： 10.1021/acs.macromol.8b01954

Web of Science

Scopus

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.7566/JPSJ.87.104602

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1678/rheology.46.171

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c8sm00948a

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.macromol.8b00447

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1038/s41467-018-04533-w

Web of Science

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

担当区分：最終著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1678/rheology.46.145

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1063/1.5001960

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c7sm01316g

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c7sm01229b

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1038/s41598-017-08501-0

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.macromol.7b00572

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acsmacrolett.7b00153

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.macromol.6b00823

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/polym9010024

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

担当区分：最終著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1080/08927022.2017.1334883

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.macromol.6b01971

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.macromol.6b01642

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.compscitech.2016.08.007

Web of Science

担当区分：最終著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

担当区分：最終著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：論文集(書籍)内論文   出版者・発行元：Computer Simulation of Polymeric Materials: Applications of the OCTA System  

DOI： 10.1007/978-981-10-0815-3_6

Web of Science

Scopus

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1063/1.4937172

Web of Science

担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1186/s40323-015-0035-7

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.macromol.5b00409

Web of Science

担当区分：最終著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

担当区分：最終著者,　責任著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1063/1.4901425

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/ma501561y

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/mz500627r

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/ma5016165

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/ma500357g

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/ma402100t

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1063/1.4794156

Web of Science

担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

担当区分：最終著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1063/1.4758320

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/app.36593

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/ma202525v

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s00397-011-0574-x

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/ma202167q

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WORLD SCIENTIFIC  

DOI： 10.1142/9789814360630_0002

CiNii Research

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/ma202166y

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/ma201717e

Web of Science

担当区分：最終著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1063/1.3658775

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s00397-011-0554-1

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.polymer.2011.03.044

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1063/1.3590276

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/ma102595f

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1063/1.3502681

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1063/1.3370346

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：一般社団法人 日本ゴム協会  

Prediction of relaxation behavior of polymeric materials from molecular architecture attracts industrial interests and scientific challenges. In this study a coarse-grained molecular model called primitive chain network model is developed. The model is capable for quantitative prediction of linear and non-linear viscoelasticity of entangled polymers. Also it is indicated that the simulation for cross-linked network is fair, though quantitative test is demanded.

DOI： 10.2324/gomu.82.459

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1063/1.3225994

Web of Science

担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1063/1.3216110

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1063/1.3140941

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/polb.21715

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/polb.21708

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/bm801442g

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.polymer.2008.10.024

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/ma8013417

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/ma800954q

Web of Science

担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s00397-008-0258-3

Web of Science

担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3139/217.2030

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1063/1.2899653

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.polymer.2007.12.032

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.jnnfm.2007.02.014

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1063/1.2790007

Web of Science

担当区分：最終著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1063/1.2747240

Web of Science

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：The Society of Polymer Science, Japan  

高分子溶融体のダイナミクスを支配するといわれる"からみ合い"だが,管模型などのからみ合いを前提とした理論の発展とは対照的にその具体的な描像の理解は遅れている。本稿では分子シミュレーションによる単一分子観察を中心に,からみ合いそのものに関する最近の研究動向を紹介する。

DOI： 10.1295/kobunshi.56.412

Scopus

CiNii Books

CiNii Research

researchmap

その他リンク： https://jlc.jst.go.jp/DN/JALC/00295142546?from=CiNii

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.colsurfb.2007.01.020

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/app.24492

Web of Science

担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s00397-006-0112-4

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.jnoncrysol.2006.01.144

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

担当区分：最終著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/masy.200651021

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/app.21503

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1063/1.1819311

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Robotics and Mechatronics  

This paper discusses a fully decentralized algorithm able to create a coherent swarm of autonomous mobile robots from the viewpoint of computational physics. To this end, we focus on Molecular Dynamics and Stokesian Dynamics, both of which are widely used to investigate many-body systems. To verify the feasibility of our approach, this idea has been implemented to a swarm of 2-D radio-connected autonomous mobile robots as a practical example. Simulation results indicate that the proposed algorithm can control the shape of the swarm appropriately based on the current situation without losing the coherence of the swarm nor exchanging global information among modules. Furthermore, we found that local interaction used to exploit Stokesian Dynamics plays an essential role to maintain the coherence of the swarm particularly in an unstructured environment.

DOI： 10.20965/jrm.2004.p0271

Scopus

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：一般社団法人 日本家政学会  

DOI： 10.11428/jhej1987.55.145

CiNii Research

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1063/1.1605382

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/S0032-3861(03)00604-9

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s00397-002-0287-2

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：一般社団法人 日本家政学会  

DOI： 10.11428/jhej1987.54.343

CiNii Research

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1122/1.1516787

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：一般社団法人 プラスチック成形加工学会  

A technique to measure planar elongational viscosity and step-planar stress relaxation, by using a lubricated squeeze flow method with PS and LDPE, has been optimized and established. The effect of experimental conditions, i.e., the viscosity of silicone oil as a lubricant, appeared in the measurement of the planar elongational viscosity. The dependence of the uniform planar deformation behavior on the silicone oil viscosity was greater in LDPE than in PS. A high viscosity silicone oil (3.0&times;10²Pa-s) was chosen to minimize the loss of lubricant. Although the step-planar stress relaxation experiments required speeds that exceeded the testing machine specification to achieve the step deformation, this problem was successfully solved by inserting a metal spacer between the lower plate and the sample. The high viscosity silicone oil produced uniform deformation in both materials with minimal loss of the lubricant, however, the high viscosity of the silicone oil was believed to lead larger measured G⁰(t) results than the predicted values. The silicone oil viscosity was optimized at a lower value of 1.0&times;10¹Pa-s which minimized the influence of the silicone oil on the results while still producing substantial lubricity. The measurement of planar elongational viscosity by using this optimal silicone oil showed strain-hardening in both samples, with LDPE showing a stronger dependence. &ldquo;Time-strain separability&rdquo; within a certain time period was confirmed for the step planar stress relaxation modulus under the optimized conditions.

DOI： 10.4325/seikeikakou.13.563

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Polymer  

Recently viscoelastic measurement has received considerable attention as a complementary method to estimate the crystallization dynamics under shear. However, because of the complex relationship between the crystallization fraction and dynamic mechanical results, it has been difficult to obtain accurate crystallization fraction under shear. To conduct the direct determination of crystallization fraction under shear, the shear flow thermal rheometer (SFTR) having differential thermal analysis (DTA) has been successfully developed using a rotational shear rheometer. Two thermocouples to measure the reference and the sample temperatures were installed at each optimal position as DTA equipment. Two sheets of polyetheretherketone (PEEK) were put on two aluminum plates to prevent heat transfer between the sample and the aluminum plates for accurate measurement of DTA. The influences of using PEEK, instead of an aluminum plate and the thermocouple on rheology results were confirmed to be negligible. In the SFTR, shear strain was given from the lower plate. Both stress and differential temperature responses were simultaneously detected by the upper plate and thermocouples, respectively. The advantage of the SFTR over conventional rheometers was that the crystallinity fraction was able to be directly determined from DTA. In non-isothermal and isothermal preliminary experiments of iso-polypropylene, it was demonstrated that the SFTR provided two kinds of data by the simultaneous measurement of DTA and viscosity. The crystallinity fraction under shear was directly estimated from DTA in the SFTR.

DOI： 10.1016/S0032-3861(99)00226-8

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

担当区分：筆頭著者   記述言語：英語  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語  

Web of Science

記述言語：英語  

Web of Science

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：一般社団法人 プラスチック成形加工学会  

Measurements of uniaxial, biaxial, and planar elongational viscosity and step stress relaxation of a low density polyethylene (LDPE) melt were carried out. The description of experimental uniaxial, biaxial, and planar elongational viscosities results by the Kaye-Bernstein-Kearsley-Zapas (K-BKZ) constitutive equation was examined. Three types of damping function forms, Wagner-Demarmels (WD) model, Papanastasiou-Scriven-Macosko (PSM) model, and Luo-Tanner (LT) model, have been proposed in the K-BKZ constitutive equation. These three damping function forms were examined to see which was able to describe the experimental shear, biaxial, and planar damping functions. The experimental shear and biaxial damping functions were described by the LT and PSM models better than the WD model, however, the experimental planar damping function was not described well by any of the three models. After estimating the best parameters in each model by fitting the three experimental damping functions, the uniaxial, biaxial, and planar elongational viscosity was calculated by the estimated parameters. The uniaxial elongational viscosity was predicted best by the LT model, then by the WD, and PSM models. For biaxial and planar elongational viscosity, none of the three models predicted well, thus the lack of suitability of the biaxial and planar elongational viscosity to the K-BKZ model was suggested.

DOI： 10.4325/seikeikakou.11.517

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Macromolecular Science - Physics  

Homogeneous polymer melts show strain hardening, while recent uniaxial elongational studies have revealed that some heterogeneous polymer melts show strain softening. A systematic description and explanation about strain hardening of homogeneous polymers and strain softening of heterogeneous polymers is still needed. Here, the Bernstein, Kearsley, and Zapas (BKZ) model is applied to give a systematic description using model relaxation spectra and model damping functions. The effects of damping function and the longest relaxation time on the strain hardening or softening are investigated in terms of intensity and critical strain. The intensity, that is, the degree of hardening or softening, is defined as the degree of positive or negative deviation from the Trouton rule. The critical strain is defined as the strain at which the deviation starts. The intensity is strongly affected by the damping function. If α, the damping parameter in the said damping function, is more than 2, strain hardening appears. With α less than 2, strain softening occurs. It is suggested that strain hardening or softening in various polymer melts is able to be characterized by showing the location of each polymer in the proposed figures. It is proposed that a systematic description in terms of the BKZ model is capable of explaining not only the strain hardening of homogeneous polymer melts, but also the strain softening of heterogeneous polymer melts.

Scopus

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Molecular Simulation  

The effect of the molecular entanglement on the elongational viscosity was investigated by Brownian dynamics simulation in 2-dimension. The polymer was represented by freely-rotated bead-rod model. The entanglement constraint was assumed by a repulsive interaction between bonds in the chain and randomly located obstacles. Under an elongational flow, affine deformation was applied to spatial distribution of the obstacles. Varying lifetime and density of the obstacles, we investigated these effect on elongational viscosity. We found that (i) linear viscosity increases with increasing density while it is independent of the lifetime, that (ii) critical strain rate at which the strain hardening begins is independent of both the lifetime and the density, that (iii) the longer lifetime gives the stronger strain hardening, and that (iv) when the density becomes higher than entanglement threshold of the chain, the strain hardening is discontinuously enlarged. Brownian dynamics; polymer rheology; strain hardening; polymer entanglement; elongational flow; elongational viscosity.

DOI： 10.1080/08927029908022068

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Zairyo/Journal of the Society of Materials Science, Japan  

Biaxial elongational rheometer using lubricated squeezing method has been installed. To start up the rheometer and to obtain reproducible and reliable data, the effects of experimental conditions on biaxial elongational viscosity data were investigated. Constant area method was preferable rather than constant volume method. It was concluded that the effects of the viscosity of silicone oil and the shape were neglisible when method of constant area was employed.

DOI： 10.2472/jsms.47.1296

Scopus

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：繊維学会  

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：繊維学会  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Web of Science

記述言語：日本語

記述言語：日本語

記述言語：日本語

記述言語：日本語

記述言語：日本語

記述言語：日本語

担当ページ：391-392   記述言語：日本語

担当ページ：339-342   記述言語：日本語

担当ページ：607-612   記述言語：日本語

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：英語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

担当区分：筆頭著者,　責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）   出版者・発行元：一般社団法人 日本レオロジー学会  

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）   出版者・発行元：一般社団法人 日本レオロジー学会  

DOI： 10.1678/rheology.50.391

CiNii Research

researchmap

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

DOI： 10.1678/rheology.50.339

DOI： 10.1678/rheology.50.339

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）   出版者・発行元：一般社団法人 日本レオロジー学会  

DOI： 10.1678/rheology.50.1

CiNii Research

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）   出版者・発行元：一般社団法人 日本トライボロジー学会  

<p>Rheology is the science for flow and deformation of matters. Although rheology is closely related to tribology as seen in the Stribeck diagram, it must be separately considered. For instance, rheology has been developed for linear viscoelasticity owing to the linear response theory, whereas the material response discussed in tribology is in general under highly non-equilibrium. Besides, even under fast and large deformations, rheological measurements are usually performed under laminar flows and non-slip boundary conditions, which are far from the tribological conditions.</p>

DOI： 10.18914/tribologist.67.01_8

CiNii Research

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：英語   掲載種別：記事・総説・解説・論説等（学術雑誌）   出版者・発行元：Nihon Reoroji Gakkaishi  

Nihon Reoroji Gakkaishi, the Journal of the Society of Rheology, Japan, has reached the milestone, the 50 th volume. We wish to rejoice with all the current and past members of the society in this memorable event. The first issue of our journal appeared in 1973 in conjunction with the founding of the society. In the greeting for the first issue, Professor Masao Horio 1), the founding president, expressed his pleasure at the launch of the journal. He described the role that the journal should play: to disseminate Japanese rheological research both domestically and internationally, introduce the situation overseas to the members, and enlighten knowledge through review articles and commentaries. These missions naturally came from the success of the 5 th International Congress on Rheology in Kyoto. (Remarkably, the Japanese rheologists organized the event before the foundation of the Japanese Society of Rheology.) Although the second one has been somewhat diminishing in recent years with the development of the internet and online publishing, the missions have been fulfilled by significant efforts by society members. In this article, let us retrospect the journal’s history according to some records to express our respect for the accumulated contributions.

DOI： 10.1678/rheology.50.147

Scopus

担当区分：筆頭著者,　責任著者   記述言語：日本語   出版者・発行元：一般社団法人 日本レオロジー学会  

DOI： 10.1678/rheology.49.49

Web of Science

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

DOI： 10.1678/rheology.48.177

記述言語：英語   掲載種別：会議報告等  

researchmap

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

DOI： 10.5650/oleoscience.19.461

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語  

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

担当区分：最終著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）   出版者・発行元：THE SOCIRETY OF RUBBER SCIENCE AND TECHNOLOGYY, JAPAN  

Although molecular simulations are useful tool for material design, it is not straightforward to apply the technique to polymeric materials due to the long relaxation time. The widely used strategy to overcome this difficulty is 'coarse-graining' where a set of slow variables is chosen and the other state variables are statistically embedded into the time evolution of the chosen variables. However, there has not been any established method in this coarse-graining procedure, and thus, semi-empirical models have been proposed for each specific problem. This review showcases such models to clarify the position of each model in the context of the coarse-graining.

DOI： 10.2324/gomu.86.113

CiNii Books

researchmap

その他リンク： https://jlc.jst.go.jp/DN/JALC/10018161280?from=CiNii

担当区分：最終著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

記述言語：日本語  

CiNii Books

researchmap

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   出版者・発行元：プラスチック成形加工学会  

CiNii Books

researchmap

担当区分：最終著者,　責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

記述言語：日本語  

CiNii Books

researchmap

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   出版者・発行元：プラスチック成形加工学会  

CiNii Books

researchmap

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   出版者・発行元：日本レオロジー学会  

CiNii Books

researchmap

担当区分：筆頭著者,　責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）   出版者・発行元：物性研究刊行会  

この論文は国立情報学研究所の電子図書館事業により電子化されました。

CiNii Research

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：会議報告等   出版者・発行元：一般社団法人 プラスチック成形加工学会  

DOI： 10.4325/seikeikakou.15.547

CiNii Research

担当区分：筆頭著者,　責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）   出版者・発行元：化学工学会  

CiNii Books

researchmap

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：会議報告等   出版者・発行元：一般社団法人 プラスチック成形加工学会  

DOI： 10.4325/seikeikakou.14.40

CiNii Research

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）   出版者・発行元：公益社団法人 日本化学会・情報化学部会  

.

DOI： 10.11546/cicsj.20.88

担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：会議報告等   出版者・発行元：一般社団法人 プラスチック成形加工学会  

DOI： 10.4325/seikeikakou.13.689

CiNii Research