著者

松本 憲治 太田 光浩 岩田 修一

出版者

一般社団法人 日本レオロジー学会

雑誌

日本レオロジー学会誌 (ISSN:03871533)

巻号頁・発行日

vol.44, no.3, pp.159-166, 2016-07-15 (Released:2016-07-15)

参考文献数

4

被引用文献数

1

---

Three-dimensional numerical simulations of the flow dynamics of milk using a volume-of-fluid (VOF) method were carried out in order to optimize the process in which milk is filled into a gable top carton with a volume of 1,000 mL. In the numerical simulations, the shear-thinning property of milk was modeled with the Carreau-Yasuda model. The sensitivity of the milk flow dynamics due to the prescribed lifting motion of the gable top carton and due to the filling speed (the number of milk cartons filled per hour) was investigated. When there was no prescribed lifting motion, it was computationally shown that milk which impinged on the bottom of the carton largely jumped and flowed outside the carton. In other words, it was found that a prescribed lifting motion can significantly reduce the amount of milk that escapes the carton. Also, it was found that the efficiency for filling a milk carton was sensitive to the filling speed. The optimum filling speed determined from fully three-dimensional numerical simulations was found to be consistent with previous investigations that used two-dimensional numerical simulations.

著者

堀中 順一

出版者

一般社団法人 日本レオロジー学会

雑誌

日本レオロジー学会誌 (ISSN:03871533)

巻号頁・発行日

vol.47, no.1, pp.31-32, 2019-02-15 (Released:2019-05-17)

著者

高橋 雅興

出版者

一般社団法人 日本レオロジー学会

雑誌

日本レオロジー学会誌 (ISSN:03871533)

巻号頁・発行日

vol.49, no.5, pp.347-359, 2021-12-15 (Released:2022-01-15)

参考文献数

64

被引用文献数

1 2

著者

岩崎 祥平 山崎 敦朗 畠山 広大 内山 陽平 井上 貴博 新田 晃平 山口 政之

出版者

一般社団法人 日本レオロジー学会

雑誌

日本レオロジー学会誌 (ISSN:03871533)

巻号頁・発行日

vol.50, no.2, pp.171-179, 2022-04-15 (Released:2022-05-15)

参考文献数

50

被引用文献数

2

---

Microporous films were obtained from an extruded sheet of isotactic polypropylene (PP) containing N,N’-dicyclohexyl-2,6-naphthalene dicarboxamide as a crystal nucleating agent under suitable hot-stretching conditions. The crystalline structure before and after the stretching operations was evaluated by two-dimensional wide-angle X-ray diffraction, and it was found that the original sheet contains a large amount of β-form crystals oriented to the transversal direction (TD) by the extrusion at 200 °C, which is lower than the dissolution temperature of the nucleating agent in PP. During stretching of the sheet, α-form crystals oriented to the stretching direction appeared by the transformation from β- to α-form crystals. Moreover, numerous microvoids were generated by stretching around at 100 °C to the machine or flow direction (MD) of the sheet, although the microvoids were prolonged. The sequential TD stretching, however, expanded the area of voids, leading to a microporous film with a pronounced porosity.

著者

小林 祥子 金田 勇

出版者

一般社団法人 日本レオロジー学会

雑誌

日本レオロジー学会誌 (ISSN:03871533)

巻号頁・発行日

vol.46, no.3, pp.139-143, 2018-06-15 (Released:2018-08-31)

参考文献数

8

被引用文献数

1

---

UDON is a type of traditional Japanese noodles. “TEUCHI UDON” are made by kneading and rolling wheat flour, cutting it into strips, and then boiling them. One of the visible characteristics of “TEUCHI UDON” is sharp edge that appears in the ridge of the noodles, and such visual effect, in addition to the mechanical properties of noodles, greatly enhances the taste. To understand why the “edge” appears in the UDON noodles, we investigated the change in the shape and mechanical properties of UDON noodles during cooking. Moreover, we performed quantitative evaluation of the “edge” using image analysis of the cross-section of the UDON noodles during cooking. Image analysis showed that the structure of the gluten network and shape of the starch granules observed in the rolling side was different from that in the cut end. Furthermore, results of compression test revealed that the mechanical characteristics of these two ends were different from each other. We suppose that there is anisotropy in the swelling behavior of UDON noodles.

著者

筒井 晃一 小林 敏勝 西沢 宏司 上野 太三郎 景山 洋行

出版者

一般社団法人 日本レオロジー学会

雑誌

日本レオロジー学会誌 (ISSN:03871533)

巻号頁・発行日

vol.25, no.5, pp.267-273, 1997-12-15 (Released:2012-11-20)

参考文献数

9

被引用文献数

2 2

---

Pigment dispersion technology plays an important role in attaining basic coating qualities such as a ”high quality appearance” and ”high durability”. Authors' experiments have quantitatively proved that a basic principle in pigment dispersion was an ”acid-base interaction between pigment and resin” in either non-aqueous or aqueous mediums, by optical and rheological measurements of pigment dispersions. These dispersions were prepared from pigments, acid-base characteristics of which were measured by a new method developed in our laboratory.A conventional pigment dispersing resin, called an ”amphoteric resin”, was also developed using a new idea that any conventional pigment having a variety of acid-base characteristics must be well dispersed, when a resin containing both acid and base functions was used.Pigments with almost no acid and/or base characteristic could be, however, well dispersed when the pigments were surface modified to have either an acid or base characteristic by plasma surface treatment. This result also supported that the ”acid-base interaction” was important in pigment dispersion.

著者

升田 利史郎 桐栄 敬二 来田村 実信 小野木 重治

出版者

一般社団法人 日本レオロジー学会

雑誌

日本レオロジー学会誌 (ISSN:03871533)

巻号頁・発行日

vol.9, no.2, pp.77-82, 1981-06-30 (Released:2012-11-20)

参考文献数

7

被引用文献数

1

---

Extensional properties at constant rates were measured for styrene-butadiene copolymers having various molecular weights and compositions. The result shows that the extensional behavior of block copolymers is affected strongly by the phase structure. Samples of intermediate compositions form two-phase structure composed of polybutadiene (PB) and polystyrene (PS) phases. Both the initial modulus of extension and failure behavior are mainly dominated by the deformation of the PB phase. The flow of PB chains at and beyond the failure point is obstructed by the PS phase. Deformation and flow of PS chains are dominant in the extensional behavior of the samples having low butadiene contents, in which the PS phase is plasticized by short PB chains. Time-temperature superposition can be applied to strain-rate dependence curves of failure stress and strain measured at different temperatures. The temperature dependence of shift factor aT obtained for the samples, which form two-phase structure, agree well with that for homo-polybutadiene, reflecting that the onset of flow of PB chains is the dominant factor governing the failure phenomenon. However, aT for the samples having low butadiene content is higher than that for other samples.

著者

小林 秀雄 浦川 理 金子 文俊 井上 正志

出版者

The Society of Rheology, Japan

雑誌

日本レオロジー学会誌 (ISSN:03871533)

巻号頁・発行日

vol.42, no.1, pp.19-23, 2014

被引用文献数

4

---

The δ-cocrystal of syndiotactic polystyrene (sPS) can capsulate various small guest molecules in the cavity of the crystalline region. We examined the rotational motion of isolated polar guest molecule, benzonitrile (BN), caged in the crystalline cavities by dielectric spectroscopy and the results were compared with the previously reported data of sPS / methyl ethyl ketone (MEK) system. The relaxation of BN in the crystalline region was specified from the comparison with the dielectric data of atactic-PS / BN system in which only the amorphous phase exists. The rotational relaxation time of BN in the crystalline cavity was 6 orders of magnitude longer, and the activation energy of BN was twice larger than those of MEK. These results suggest that spatial restriction due to the small cavity size strongly retards the rotational dynamics of the larger guest molecule, BN. Two-site model could successfully describe the temperature dependence of the dielectric intensity for sPS / BN system, revealing that there exist two stable states of BN molecules with energy difference of 7.42 kJmol^{<font size="-1">-1</font>} in the crystalline cavity.

著者

川﨑 猛史

出版者

一般社団法人 日本レオロジー学会

雑誌

日本レオロジー学会誌 (ISSN:03871533)

巻号頁・発行日

vol.50, no.1, pp.63-67, 2022-02-15 (Released:2022-03-15)

参考文献数

28

被引用文献数

1

---

Flow curves on dense suspensions exhibit highly nonlinear behaviors consisting of shear thinning, shear thickening, and multiple Newtonian regions. Moreover, it has recently been revealed that each Newtonian viscosity diverges individually with increasing density and is respectively related to the glass and jamming transitions. In this review, recent advances in physics are introduced regarding the complex flow behaviors in dense suspensions and its relation to the glass and jamming transitions. In addition, a numerical simulation model, focusing mainly on discontinuous shear thickening, is presented to provide microscopic insight into the complex flow behaviors, i.e., the role of thermal fluctuations and interparticle forces acting on the particles. Finally, a perspective on discontinuous shear thickening is presented with reviewing recent experimental and theoretical (numerical) works.

著者

山口 政之 木田 拓充

出版者

一般社団法人 日本レオロジー学会

雑誌

日本レオロジー学会誌 (ISSN:03871533)

巻号頁・発行日

vol.49, no.5, pp.361-363, 2021-12-15 (Released:2022-01-15)

参考文献数

10

著者

梅屋 薫 菅野 隆志 我妻 誠 五十嵐 秀明

出版者

一般社団法人 日本レオロジー学会

雑誌

日本レオロジー学会誌 (ISSN:03871533)

巻号頁・発行日

vol.3, no.4, pp.145-148, 1975-12-31 (Released:2012-11-20)

参考文献数

10

被引用文献数

1

著者

三浦 靖

出版者

一般社団法人 日本レオロジー学会

雑誌

日本レオロジー学会誌 (ISSN:03871533)

巻号頁・発行日

vol.42, no.4, pp.265-266, 2014-10-15 (Released:2014-10-08)

参考文献数

1

被引用文献数

1 4

著者

Yusuke Yasuda Hiroki Matsunobu Tetsuharu Narita Hideaki Yokoyama Koichi Mayumi Kohzo Ito

出版者

The Society of Rheology, Japan

雑誌

日本レオロジー学会誌 (ISSN:03871533)

巻号頁・発行日

vol.48, no.3, pp.161-168, 2020-06-15 (Released:2020-07-15)

参考文献数

27

被引用文献数

1

---

In slide-ring (SR) gels, polymer chains are cross-linked by rings and can slide through the cross-linking points. The high chain mobility in SR gels is responsible for their unique physical properties such as softness, high deformability, and crack resistance. In this study, the dynamics of the polymer network in SR gels was investigated by the microrheological technique. The diffusion coefficients of the silica nanoparticles in SR gels with different cross-linking densities were measured by dynamic light scattering (DLS). It was found that the diffusion coefficient of the probe particles in the SR gels does not decrease monotonically with increasing cross-linking density even though their mesh sizes are close to the particle size. This suggests that the slidability of the cross-linking points enhances fluctuation of the polymer networks in the SR gels.

著者

中村 浩 舘 和幸

出版者

一般社団法人 日本レオロジー学会

雑誌

日本レオロジー学会誌 (ISSN:03871533)

巻号頁・発行日

vol.27, no.3, pp.161-164, 1999-09-15 (Released:2000-03-28)

参考文献数

8

被引用文献数

3 3

---

Effects of base hydrophobicity on a flow behavior and a microstructure of aqueous suspension of core-shell type carboxylated polymer particle have been studis. The suspension was neutralized by NaOH, dimetylaminoethanol(DMAE), dimetylaminopropanol(DMAP) and dimetylaminobutanol(DMAB). Steady shear flow was measured with a coni-clinder rotational rheometer, and microstructure was examined with a dynamic oscillating shear method and the small angle X-ray scattering(SAXS) method. The hydrophobicity is DMAB>DMAP>DMAE>NaOH. The distance ξ between center to center of neighboring particles in ordered structure made of the particles was measured by SAXS method. In case of NaOH, the suspension indicated shear-thinning flow. Loss tangent tan δ was below 1(G'>G") in all frequency region and a diffraction peak in SAXS profile was detected. These results show the three dimensional network structure of ordered structure is formed in the suspension. As the hydrophobicity increased, viscosity and degree of shear-thinning decreased, tan δ became above 1 in almost frequency region and the height of diffraction peak decreased without changing ξ. These results suggest that, as the base hydrophobicity increased, the three dimensional network structure reduces to the isolated domain structure, though the distance between neighboring particles in ordered structure does not change.

著者

松本 浩次郎 西岡 利恭 藤田 和代

出版者

日本レオロジー学会誌

雑誌

日本レオロジー学会誌 (ISSN:03871533)

巻号頁・発行日

vol.17, no.3, pp.135-144, 1989

被引用文献数

1

著者

西成 勝好

出版者

一般社団法人 日本レオロジー学会

雑誌

日本レオロジー学会誌 (ISSN:03871533)

巻号頁・発行日

vol.36, no.5, pp.195-202, 2008-12-15 (Released:2009-02-17)

参考文献数

54

被引用文献数

1 1

---

Rheological and related physicochemical studies on biopolymers are reviewed. Methods of determining viscoelastic constants of cylindrical gels were proposed and applied to various polymer gels. This was convenient to study the rheological changes induced by diffusion of ions into gels, and those induced by retrogradation of starch gels. A reel-chain model was proposed to understand the temperature dependence of elastic modulus of thermoreversible gels such as agarose, gelatin, poly(vinyl alcohol), gellan etc. This model was extended recently to understand the large deformation and yield behaviour of physical gels. Gelation process of various food biopolymers, soybean protein, casein, konjac glucomannan, gellan as well as the interaction between different biopolymers have been studied by dynamic viscoelastic measurement in combination with other physicochemical methods. Rheological behaviors of hyaluronan, a major component of synovial fluid, and of schizophyllan, anti-tumor active and very rigid rod polysaccharide, were studied. Viscoelastic properties of films of polysaccharides, amylose, pullulan, cellulose derivatives, konjac glucomannan were studied as a function of temperature and were analysed from the view point of molecular motion with NMR and dielectric studies as a basis of molecular understanding of biodegradability.

著者

栄永 義之 藤田 博

出版者

一般社団法人 日本レオロジー学会

雑誌

日本レオロジー学会誌 (ISSN:03871533)

巻号頁・発行日

vol.12, no.3, pp.136-141, 1984-09-20 (Released:2012-11-20)

参考文献数

35

被引用文献数

4

---

Literature data on the self-diffusion coefficient Ds of linear polymers in bulk and solution have been reexamined. The major conclusions are as follows:(a) The currently accepted relation for Ds as a function of polymer molecular weight M and concentration cp, i. e., Ds∝M-2,p-1.75 (i) is not exactly followed by the data, though it is usually taken as evidence for the reptation motion of a polymer chain assumed in the tube theory and also for the scaling theory.(b) The experimental data examined suggest that Ds tends to obey the relation Ds∝M-2.5 (ii) for M>Mc, the critical molecular weight for the onset of entanglement, and Ds∝M-1 (iii) for M<Mc, with a smooth transition between the two regions. Equation (ii) is consistent with the relation expected from viscoelastic data on polymer concentrates.

著者

八尾 滋 宮川 淑人 松本 孝芳

出版者

一般社団法人 日本レオロジー学会

雑誌

日本レオロジー学会誌 (ISSN:03871533)

巻号頁・発行日

vol.14, no.2, pp.77-81, 1986-06-20 (Released:2012-11-20)

参考文献数

11

---

Linear and nonlinear viscoelastic properties of disperse systems of photosensitive particles were studied in relation to the degree of aggregation of dispersing particles. The disperse system has the characteristic long-time relaxation process attributed to the aggregate structure of dispersing particles. In that relaxation process, the system in which the dispersing particles aggregate in some degree shows markedly nonlinear viscoelasticity. The characteristic relaxation time in the long-time relaxation process can be closely related with the rotational diffusion of the aggregate. It is also shown that the characteristic relaxation time is independent of the dynamic strain amplitude.

著者

二瓶 智也 山縣 義文 山本 信之

出版者

一般社団法人 日本レオロジー学会

雑誌

日本レオロジー学会誌 (ISSN:03871533)

巻号頁・発行日

vol.34, no.2, pp.83-89, 2006 (Released:2006-06-14)

参考文献数

33

被引用文献数

1

---

We have developed a non-water gel comprised of polyethylene glycol (PEG) and hydroxypropylcellulose (HPC) as a gelling agent. We investigated the gelation mechanism of the HPC/PEG system on the basis of a stress-controlled rheometer and an X-ray diffractometer. From these results, we found that two gelation mechanisms coexisted in the HPC/PEG system; the entanglement of interacting HPC polymer chains which behave like a flexible polymer and the cross-linking of the microcrystalline domains of the HPC main chains. In the lower HPC concentration range, the gelation is dominated by the cross-linking of the microcrystalline domains of the HPC main chains. In the higher HPC concentration range, on the other hand, the gelation is dominated by the entanglement of interacting HPC polymer chains.

著者

原田 雅史 舘 和幸 鈴木 泰彦 池野 順一 梅村 晋

出版者

一般社団法人 日本レオロジー学会

雑誌

日本レオロジー学会誌 (ISSN:03871533)

巻号頁・発行日

vol.34, no.2, pp.71-75, 2006 (Released:2006-06-14)

参考文献数

10

被引用文献数

2

---

Viscosity is a key property controlling the appearance of automotive coatings. However, the direct measurements of the viscosity in automotive coatings have not been achieved, since the automotive coating is a complex system consisting of a multilayer where mass transfer occurs between each thin layers. Using the laser trapping method, we have developed a rheometer to realize non-destructive viscosity measurements of the multilayers. Applying the new rheometer to automotive coatings, the viscosity has been estimated for (A) a clearcoat itself, (B) a clearcoat on a basecoat, and (C) a clearcoat on a basecoat and a surfacer. The results demonstrate an increase of viscosity in the order of (A) < (B) < (C), depending on the thickness of the lower layers. The viscosity increase suggests that the concentration of the clearcoat is likely to increase due to the diffusion of the solvent into the lower layers.