巻号一覧
55 巻, 11 号
選択された号の論文の12件中1～12を表示しています
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Masatoshi Tokita, Seizo Miyata, Kensuke Osada, Junji Watanabe1999 年 55 巻 11 号 p. 502-510
発行日: 1999/11/10
公開日: 2008/11/28
ジャーナル フリーThe solid state morphology of poly (methylene p, p′-bibenzoate) (BB-n) was studied by the small-angle X-ray scattering (SAXS) method. The BB-n polyesters with n of 6 and 8 form isotropic, smectic A, and crystal phases in the order of decreasing temperature; thereby their crystallization taking place from the smectic A phase. The SAXS for the crystalline specimens shows the well-defined reflection maxima which are attributable to the stacked lamellar structure. The lamellar spacings are distributed around 250-300 Å so that an appreciable number of chain foldings are included in a chain. The lamellar size is increased by annealing the crystal like in other crystalline polymers. In contrast, it is not essentially altered by annealing the preceding smectic A phase. Most interesting is that the lamellar spacing increases with a decrease in the crystallization temperature. The trend is contrary to that observed in conventional polymers as well as in BB-10 and BB-12 which crystallize from the isotropic melt and can be explained if in the preceding smectic A phase the chain foldings exist at a thermodynamic equilibrium as an entropy effect. Such a chain folding was also predicted from anomalous orientation of molecules in the fibers drawn from the smectic melt. In these fibers, the polymer chains align in a direction perpendicular to the fiber axis. This orientation is completely retained even if the fiber is further elongated up to the strain of 100%. These results suggest that the chain foldings take place at a limited space to form the lamellar smectic domain.抄録全体を表示PDF形式でダウンロード (2596K) -
辻 正樹, 辻本 純一, 村上 昌三, 〓谷 信三1999 年 55 巻 11 号 p. 511-521
発行日: 1999/11/10
公開日: 2008/11/28
ジャーナル フリーUnaxially oriented films of poly (tetramethylene succinate) [PTMS] were prepared by drawing at room temperature [r. t.]. The films were deformed by tensile extension at r. t., held under a fixed-strain condition at r. t. or at 107°C, and then strain-released at r. t. These processes were examined by the stress-strain [S-S] measurement and the in situ time-resolved wide-angle X-ray diffraction [WAXD] using an Imaging Plate system. The range of strain (ε) utilized in this study was 0_??_ε<25%.
In the range of ε where the α_??_β crystalline phase transition takes place, the slope of the S-S curve for each of the extension and strain-releasing processes was smaller than those before and after this range of ε. In the holding processes at a fixed strain (ε=22_??_23%), any significant difference in WAXD pattern was not recognized between the holding at r. t. and that at 107°C, though the crystalline reflections became sharp and the stress relaxation was fairly promoted at the higher temperature. In the strain-releasing process at r. t. after holding at 107°C, however, the range of ε for the α_??_β transition was shifted to the higher strain side. It was concluded that “stress”, not strain, should be a major factor for inducing the transition, and the “critical stress” at r. t. was estimated at about 100MPa.
As a mechanical model for the uniaxially oriented PTMS film, the Series-Parallel model with two kinds of amorphous components was found to be adequate for tensile extension at r. t.: One amorphous component is connected in series to the crystalline component, and the other is connected in parallel to the composite of crystalline and amorphous components which are in series. It is considered that the series component has a long relaxation time, but that the parallel one has a shorter relaxation time and can be readily relaxed even at r. t.抄録全体を表示PDF形式でダウンロード (2630K) -
Yasuo Gotoh, Yutaka Ohkoshi, Masanobu Nagura1999 年 55 巻 11 号 p. 522-527
発行日: 1999/11/10
公開日: 2008/11/28
ジャーナル フリーFilms of zinc, calcium and aluminum salts of poly (acrylic acid) (PAA) were prepared from their powdery salts by compression molding at 190_??_200°C, 600MPa for 0.5hr and their mechanical and thermal properties were investigated. From the results of the dynamic mechanical thermal analysis the storage modulus of each PAA salts exhibited about 20GPa at room temperature because of highly intermolecular crosslinking of PAA by metal ions. Modulus of PAA calcium salt was 7GPa even at 400°C, while modulus of zinc salt and aluminum salt of PAA decreased abruptly above 200°C. This decrease of modulus was attributed to the abrupt elimination of H2O, which coordinated to metal ions, from specimens at high temperature.抄録全体を表示PDF形式でダウンロード (1084K) -
Shigenobu Yamanaka, Yoshiaki Yuguchi, Hiroshi Urakawa, Kanji Kajiwara, ...1999 年 55 巻 11 号 p. 528-532
発行日: 1999/11/10
公開日: 2008/11/28
ジャーナル フリーThe enzymatic degradation by β-galactosidase results in the thermoreversible gelation of TSP xyloglucan aqueous solution. Its gelling process was observed by time-resolved small-angle X-ray scattering, and the results were analyzed according to the classic Flory-Stockmayer theory, where the tree-like model was modified in order to take into account the formation of ordered condensed phase composed of aligned xyloglucan chains in parallel. The analysis yielded the formation of the ordered condensed phase progressing with time up to a gel point. Here the ordered phase functions as a branch unit in the model analysis.抄録全体を表示PDF形式でダウンロード (378K) -
Masaya Ueda, Shinichi Sakurai, Shunji Nomura1999 年 55 巻 11 号 p. 533-541
発行日: 1999/11/10
公開日: 2008/11/28
ジャーナル フリーCrystallization behavior and structure in crystalline block copolymer and its blend with crystalline homopolymer were studied using differential scanning calorimetry (DSC), small-angle X-ray scattering (SAXS), and small-angle light scattering (SALS). The crystalline block copolymer subjected to present work was polyethylene-block-poly (ethylene-alt-propylene), PE-PEP, which was used for crystalline block component of the crystalline homopolymer/crystalline block copolymer blend. Hydrogenated polybutadiene (HBD-2) was chosen as the crystalline homopolymer component of the blend. The HBD-2/PE-PEP (50/50 by weight) blend provided characteristic cocrystallization, which was confirmed by DSC, SAXS and SALS, resulting from the similar polyethylene-like segments in both components. In the blend, two crystallizable components cocrystallized into a single type of lamellar structures as revealed by single peak in DSC. The spherulites sizes and integrated intensities change during crystallization both obtained from SALS measurements supported cocrystallization. Both in block copolymer and the blend, multiple SAXS peaks suggested that microphase separation driven by crystallization took place in microscopic scale, whereas spherulites formation in macroscopic scale was also developed, which was confirmed by SALS results.抄録全体を表示PDF形式でダウンロード (1367K) -
Ken Miyata, Hiroshi Ito, Takeshi Kikutani, Norimasa Okui1999 年 55 巻 11 号 p. 542-551
発行日: 1999/11/10
公開日: 2008/11/28
ジャーナル フリーThe as-spun poly (ethylene 2, 6-naphthalene dicarboxylate) (PEN) fibers prepared at take-up velocities of 3, 5, 7 and 9km/min were annealed. The annealing was done at 200, 240, 280 and 290 °C at a fixed length and the structure and properties of the annealed fibers were investigated. The wide-angle X-ray diffraction (WAXD) measurements revealed that α and β form crystals coexist in both the as-spun and annealed fibers. The weight fractions of α and β form crystals and amorphous phase were evaluated combining the data from WAXD and density measurements. The α form crystals dominated the fiber structure when the PEN fibers prepared at low take-up velocities were annealed at low temperatures whereas the β form crystals dominated the fiber structure when the PEN fibers prepared at high take-up velocities were annealed at high temperatures. When the PEN fibers obtained at 9km/min were annealed at 290°C, the weight fraction of β modification crystals reached 49%. Amorphous birefringence of annealed fibers was also evaluated from birefringence and crystalline orientation factors considering the difference in the intrinsic birefringence of α and β form crystals. The properties of PEN fibers with high β form content can be characterized by the relatively low amorphous orientation, high density and high melting point.抄録全体を表示PDF形式でダウンロード (706K) -
山口 貞充, 辻 正樹1999 年 55 巻 11 号 p. 552-554
発行日: 1999/11/10
公開日: 2008/11/28
ジャーナル フリーA thin film of poly (vinylidene fluoride) [PVDF] was made by casting its solution in N, N-dimethylacetamide [DMA] onto the water surface, and was examined by transmission electron microscopy [TEM]. Particle-like objects of ca. 0.2_??_0.3μm in diameter were observed in the film. Then, each particle-like object was found to be made up of fine particles, and was similar in morphology to the emulsion particle of PVDF.
Fibrous precipitates were prepared by pouring the solution into well- stirred water. By TEM of the three-stage surface replica of the fibrous precipitates, fine particles of 20_??_40nm in diameter were recognized on the surfaces of the precipitates.
These results, therefore, suggest that PVDF might be dissolved in DMA with its fine-particle shape being weakly maintained.抄録全体を表示PDF形式でダウンロード (1728K) -
原田 昭1999 年 55 巻 11 号 p. P374-P380
発行日: 1999/11/10
公開日: 2008/11/28
ジャーナル フリーPDF形式でダウンロード (4851K) -
今岡 春樹1999 年 55 巻 11 号 p. P382-P385
発行日: 1999/11/10
公開日: 2008/11/28
ジャーナル フリーPDF形式でダウンロード (951K) -
中嶋 利夫1999 年 55 巻 11 号 p. P386-P390
発行日: 1999/11/10
公開日: 2008/11/28
ジャーナル フリーPDF形式でダウンロード (2830K) -
鞠谷 雄士1999 年 55 巻 11 号 p. P391-P396
発行日: 1999/11/10
公開日: 2008/11/28
ジャーナル フリーPDF形式でダウンロード (2624K) -
梶山 宏史1999 年 55 巻 11 号 p. P397-P399
発行日: 1999/11/10
公開日: 2008/11/28
ジャーナル フリーPDF形式でダウンロード (846K)
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