巻号一覧
42 巻 (2016)
- 6 号 p. 203-
- 5 号 p. 163-
- 4 号 p. 125-
- 3 号 p. 89-
- 2 号 p. 49-
- 1 号 p. 2-
42 巻, 2 号
選択された号の論文の5件中1～5を表示しています
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研究論文
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田中 基嗣, 安部 俊一郎, 野原 勇太, 瀬戸 直樹, 斉藤 博嗣, 金原 勲2016 年 42 巻 2 号 p. 49-58
発行日: 2016/03/15
公開日: 2017/04/06
ジャーナル フリーThe purpose of this study was the clarification of mechanisms where the introduction of photo-dissociable protecting groups affects mechanical and hydrolysis properties of PLA, by combination of experiments and molecular simulation, aiming to obtain a guideline to design the optimum introduction condition. First, the mechanism of decreasing in elastic modulus of PLA by introduction of protecting groups was discussed using a molecular dynamics simulation. As a result, it was suggested that the deflection of helical molecular structure of PLA is one of the main reasons. Secondary, the change in introduction efficiency of protecting groups was experimentally evaluated using a FT-IR. Here, the temperature of introduction process and the amount of protecting groups was varied. In addition, its mechanism was discussed based on a molecular orbital calculation. As results, it was suggested that the introduction efficiency of protecting groups into carboxyl end groups of PLA is determined by the relation between the total energy of the reaction field and the activation energy between protecting groups and reaction sites, resulting in elucidation of existing range of the optimum introduction condition.抄録全体を表示PDF形式でダウンロード (1622K) -
仁内 隆志, 小柳 潤, 井上 遼, 向後 保雄2016 年 42 巻 2 号 p. 59-66
発行日: 2016/03/15
公開日: 2017/04/06
ジャーナル フリーThe interfacial strength between carbon and phenolic resin is studied by using molecular dynamics simulations in order that carbon reinforced carbon matrix composites (C/C composites) has better the tensile strength. Simulations are performed by two carbon fiber models, one of which has only carbon atoms and the other has carbon atoms and some fluorinated carbon groups. Carbon fiber models are regarded as two-layer graphite and phenolic resin model is treated as cross linked structures. All force field parameters are based on Dreiding force field. Tensile stress and interfacial fracture energy are calculated for the estimation of interfacial strength. Results of the model including fluorinated carbon groups get lower interfacial strength than that of having only carbon atoms up to a certain coating ratio of fluorinated carbon groups. In the same way, within the limits of coating ratio, it shows that interfacial fracture energy of fluorinated carbon fiber model becomes lower than that of carbon fiber model having only carbon atoms.抄録全体を表示PDF形式でダウンロード (7665K) -
竹内 健都, 松崎 亮介, 岡部 朋永, 大矢 豊大2016 年 42 巻 2 号 p. 67-75
発行日: 2016/03/15
公開日: 2017/04/06
ジャーナル フリーThe study worked out an efficient optimization of heat fusion conditions between thermoplastics using molecular dynamics (MD) and a response surface method. The heat fusion process between polypropylene (PP) and polyethylene (PE) and the uniaxial elongation for evaluation of the interfacial bonding strength were modeled by using coarse-grained MD simulation. To determine the optimal conditions of heat fusion, experimental points were selected on the basis of a central composite design, and a second-order polynomial response surface was created by setting temperature, pressure, and polymerization degree as explanatory variables and the strength of fused interface as the response. The obtained optimal solution under constrained conditions yielded the highest strength compared with other experimental points and random points.抄録全体を表示PDF形式でダウンロード (7355K) -
大矢 豊大, 犬山 恭介, 岡部 朋永, 小柳 潤, 松崎 亮介2016 年 42 巻 2 号 p. 76-81
発行日: 2016/03/15
公開日: 2017/04/06
ジャーナル フリーCharacteristics of laminated graphene oxide (LGO) nanocomposite, expected for high functional composites, are known to be related to its microstructure. In this study, we investigated influences of both hydrogen-bonding and cross-linked network structures on initial stiffness and yield stress by molecular dynamics simulations. Our results showed each structure improved the mechanical properties, and the combination of these structures made the properties stronger. Moreover, we revealed the physical origin of the enhancement is caused by cross-linked networks generate stretched polymers that connect graphene sheets. Our study is expected to give a suggestion to appropriate selection of materials for highly performance LGO nanocomposite.抄録全体を表示PDF形式でダウンロード (1163K) -
影山 友哉, 小柳 潤, 喜多村 竜太, 荻原 慎二2016 年 42 巻 2 号 p. 82-87
発行日: 2016/03/15
公開日: 2017/04/06
ジャーナル フリーGenerally, polymer materials such as polypropylene shows a strong time and temperature dependence (viscoelastic behavior). It is reported that deformation could be predict by applying time–temperature superposition principle to long-term viscoelastic behavior. In this study, whether time–temperature superposition principle completed in deformation was checked using a molecular dynamics. Therefore, stress-relaxation test and constant strain rate tensile test were employed for amorphous polypropylene by molecular dynamics. Stress-relaxation tests were performed in 5 temperature standards, and relaxation moduli were gotten. Using the results, master curve was drawn, and shift factor were gotten. Next, the constant strain rate tensile tests were performed in 4 strain speed and 5 temperature standards. The results agree well with the theory curve that demanded from the parameter mentioned above, and Arrhenius equation was applied between temperature–time. Furthermore, the temperature dependence of the volume was checked, and a flexural point was occurred in shift factor. This flexure point almost accorded with a glass transition point (307[K]). It was suggested that time–temperature superposition principle completed in the small transformation of polymer materials.抄録全体を表示PDF形式でダウンロード (2000K)
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