巻号一覧
22 巻 (1994)
- 4 号 p. 185-
- 3 号 p. 111-
- 2 号 p. 57-
- 1 号 p. 5-
22 巻, 3 号
選択された号の論文の8件中1～8を表示しています
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1. ゼロずり粘度大島 淳行, 工藤 博幸, 佐藤 尚弘, 寺本 明夫1994 年 22 巻 3 号 p. 111-116
発行日: 1994/09/15
公開日: 2012/11/20
ジャーナル フリーZero shear viscosities η0 were measured for toluene solutions of ten fractionated poly (n-hexyl isocyanate) (PHIC) samples from dilute regime to concentrated isotropic regime. PHIC is a semiflexible polymer with the persistence length q=37 nm in toluene. For six PHIC samples with the molecular weight less than 14×104, the dependence of η0 on the polymer concentration c did not obey any power law, while for the higher molecular weight samples, η0 was almost proportional to c3.2 in a high c region. At fixed c, η0 was almost proportional to Mv4 in a high Mv region (Mv: viscosity average molecular weight). These concentration and molecular weight dependences are distinct from not only those for flexible polymer solutions but also those for much stiffer polymer solutions (e. g., schizophyllan (q=200 nm) and xanthan (q=120 nm)).
The results of η0 for PHIC solutions obtained were compared with Teraoka-Hayakawa's theory for rodlike polymer solutions and with our fuzzy cylinder model theory for semiflexible polymer solutions. The former theory agreed with the experimental results only for the second lowest molecular weight sample with a rodlike conformation. On the other hand, the latter theory succeeded in explaining quantitatively the results for 7 samples with intermediate molecular weights. Neither of the theories agree with the data for the lowest molecular weight sample, because they neglected the intermolecular hydrodynamic interaction which becomes important for short chain polymers. For the two highest molecular weight samples, the fuzzy cylinder model theory failed to describe the η0 data, because of some additional flexibility effect which is not cleared yet.抄録全体を表示PDF形式でダウンロード (925K) -
2. 誘電分散浅野 昌史, 楠岡 裕幸, 大島 淳行, 佐藤 尚弘, 寺本 明夫1994 年 22 巻 3 号 p. 117-122
発行日: 1994/09/15
公開日: 2012/11/20
ジャーナル フリーDielectric dispersion were measured for a semiflexible polymer, poly (n-hexyl isocyanate) (PHIC), in dilute through concentrated, isotropic solutions. Since PHIC has a dipole moment parallel to the chain contour, its dielectric dispersion reflects the fluctuation of the end-to-end vector of the polymer. For lower molecular weight PHIC samples with rodlike nature (the Kuhn statistical segment number N?0.53), the dispersion for the permittivity ε′ and the loss factor ε″ almost obeyed the simple Debye relation irrespective of the polymer concentration c, and the c dependence of the dielectric relaxation time τD was favorably compared with the fuzzy cylinder model theory. On the other hand, for higher molecular weight PHIC samples (N?0.69), the dispersion curves for ε′ and ε″ deviated from the Debye relation and the c dependence of τD did not agree with the prediction of the fuzzy cylinder model theory. These disagreements may ascribe to the chain flexibility effect for the higher molecular weight samples.抄録全体を表示PDF形式でダウンロード (738K) -
石室 良孝, 石切山 一彦, 北野 幸重, 藤井 能成1994 年 22 巻 3 号 p. 123-128
発行日: 1994/09/15
公開日: 2012/11/20
ジャーナル フリーThe isothermal crystallization of poly (phenylene sulfidesulfone) (PPSS) from N-methylpyrrolidone (NMP) solutions has been monitored by a viscoelastic technique. We have observed four characteristic changes which occur with increasing time in 20wt% solution at 24°C; (i) a decrease in η*, (ii) a steep incrase in G′, (iii) a slightly decrease in η*, and (iv) an incrase in η* and G′. These changes indicate the crystallization process from a nucleation to a aggregation. Furthermore, the crystallization at several temperatures and of poly (ethylene terephthalate) (PET), poly (buthylene terephthalate) (PBT) melts was measured similarly. It was found that the rate of crystallization of PPSS from NMP solutions is very slow, and its temperature dependence is very small.抄録全体を表示PDF形式でダウンロード (703K) -
黄 義正, 井上 正志, 尾崎 邦宏, 高野 敦志1994 年 22 巻 3 号 p. 129-134
発行日: 1994/09/15
公開日: 2012/11/20
ジャーナル フリーComplex Young's modulus, E*(ω), and complex strain-optical coefficient, O*(ω), of Poly (2-vinylnaphthalene) (P2VN) were studied in the glass-to-rubber transition zone at frequencies ranging from 1 to 130 Hz at various temperatures between 145°C and 200°C. In comparing the master curves of E*(ω) and O*(ω), we apply the modified stress-optical rule to deliberate the glass transition modulus attributable to different relaxation mechanisms. The characteristics of master curves are also compared with those of polystyrene (PS), poly(α-methylstyrene) (PMS), and polycarbonate (PC) in view of their chemical structures. The stress-optical coefficient, CR, determined in the rubbery zone, is -8.3×10-9Pa-1, which is 1.6 times larger than that of PS. The large negative value may be due to the large optical anisotropy of naphthyl side group. In the glassy zone, the relative rate of decrease of E″(ω) with ω is lower compared with the other polymers. This behavior is believed to be attributed to β relaxation of large naphthyl side group. Compared with the strain-optical coefficients of three other polymers, the O″(ω) of P2VN is found to be inactive to the β relaxation.抄録全体を表示PDF形式でダウンロード (929K) -
Numerical AnalysisHiroshi YAMAGUCHI1994 年 22 巻 3 号 p. 135-143
発行日: 1994/09/15
公開日: 2012/11/20
ジャーナル フリーViscoelastic flow at a region of a circular pipe entrance was examined numerically. The numerical calculation was achieved by using I. C. E (Implicit Continuous-fluid Eulerian) technique with the K-BKZ type consitutive equation. The transient flow characteristics with the sudden stand-up were obtained. The resultant flow field and its associated flow parameters of the K-BKZ integral consitutive equation were compared with the Newtonian case and the Oldroyd-B model. It is revealed that flow is largely affected by a choise of the Deborah number. When the Deborah number is high enough for a fixed Reynolds number, there would be a circulation zone at the entrance region of the pipe by the effects of the viscoelasticity, which cannot be observed with the Newtonian flow.抄録全体を表示PDF形式でダウンロード (1133K) -
前田 修一, 亀井 衛一1994 年 22 巻 3 号 p. 145-154
発行日: 1994/09/15
公開日: 2012/11/20
ジャーナル フリーDynamic viscoelastic properties of phase-separated polypropylene (PP)/styrene-acrylonitrile copolymer (SAN), PP/ethylene-propylene-rubber (EPR) and nylon6 (PA)/SAN blends prepared by melt-blending were measured in molten state. As characteristic to heterogeneous liquids, slow relaxation mechanisms due to domain structures of sizes ≅ 0.1-20 μm were found for dynamic moduli of three blends. These moduli were compared with predictions of an emulsion model of Palierne developed for concentrated emulsions. The emulsion model with parameters determined for the components extracted from the blends quantitatively described the properties of the blends. This result suggested that the slow relaxation mechanisms of incompatible polymer blends were attributed to recovery of domain shape and different in nature from those of polymeric systems being filled with inorganic solids and/or cross-linked rubber particles.抄録全体を表示PDF形式でダウンロード (1456K) -
野村 孝夫, 西尾 武純, 前田 修一, 亀井 衛一1994 年 22 巻 3 号 p. 155-164
発行日: 1994/09/15
公開日: 2012/11/20
ジャーナル フリーHeterogeneous textures due to phase separation in molten polypropylene (PP) / ethylene-propylene-rubber (EPR) blends were investigated in relation to their dynamic viscoelastic properties. As characteristic to heterogeneous liquids, slow relaxation mechanisms due to the existence of such phases were found for dynamic moduli of PP/EPR blends. These moduli were analyzed by using the linear viscoelastic constitutive equation for an emulsion model developed for the concentrated emulsion and the blending equation for dissimilar polymer system. The results show that the matrix of PP/EPR blends is not pure PP but the mixture of PP and EPR. For the same blend composition, the EPR concentration in the matrix PP phase was larger for EPR containing more propylene units. For the blends having the same EPR, the EPR concentration in the matrix was larger for higher EPR content.抄録全体を表示PDF形式でダウンロード (1452K) -
野村 孝夫, 西尾 武純, 前田 修一, 亀井 衛一1994 年 22 巻 3 号 p. 165-172
発行日: 1994/09/15
公開日: 2012/11/20
ジャーナル フリーHeterogeneous textures in phase separated, solid polypropylene (PP) /ethylene-propylene-rubber (EPR) blends were investigated in relation to their dynamic viscoelastic properties. The glass transition temperature (Tg) of amorphous PP phase in PP/EPR blend quenched from molten state varies with propylene content of EPR as well as EPR content in blend. The Tg depends on the concentration of EPR dissolved in the amorphous PP phase. On the other hand, the Tg of EPR phase in PP/EPR blend is about the same as that of pure EPR. This fact means that PP molecules were not dissolved in EPR phase. For the same blending composition, the EPR concentration in matrix PP phase was larger for EPR having more propylene units. When the same EPR was used, the EPR concentration in the matrix was larger for blends with larger EPR content. The EPR concentration in the amorphous PP phase of PP/EPR blend in solid state is about the same as that in molten state, indicating that the EPR concentration in solid state was essentially determined by the EPR concentration in molten state.抄録全体を表示PDF形式でダウンロード (1598K)
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