Yoshiro Takada  Kiyomi Shinbo  Yoshihiro Someya  Mitsuhiro Shibata 《应用聚合物科学杂志》2009,113(1):479-484

Glycerol polyglycidyl ether (GPE) and polyglycerol polyglycidyl ether (PGPE) were cured with ε‐poly(L ‐lysine) (PL) using epoxy/amine ratios of 1 : 1 and 2 : 1 to create bio‐based epoxy cross‐linked resins. When PGPE was used as an epoxy resin and the epoxy/amine ratio was 1 : 1, the cured neat resin showed the greatest glass transition temperature (T_g), as measured by differential scanning calorimetry. Next, the mixture of PGPE, PL, and montomorillonite (MMT) at an epoxy/amine ratio of 1 : 1 in water was dried and cured finally at 110°C to create PGPE‐PL/MMT composites. The X‐ray diffraction and transmission electron microscopy measurements revealed that the composites with MMT content 7–15 wt % were exfoliated nanocomposites and the composite with MMT content 20 wt % was an intercalated nanocomposite. The T_g and storage modulus at 50–100°C for the PGPE‐PL/MMT composites measured by DMA increased with increasing MMT content until 15 wt % and decreased at 20 wt %. The tensile strength and modulus of the PGPE‐PL/MMT composites (MMT content 15 wt %: 42 and 5300 MPa) were much greater than those of the cured PGPE‐PL resin (4 and 6 MPa). Aerobic biodegradability of the PGPE‐PL in an aqueous medium was ～ 4% after 90 days, and the PGPE‐PL/MMT nanocomposites with MMT content 7–15 wt % showed lower biodegradability. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

    

Takayuki Maehara  Junji Takenaka  Kenji Tanaka  Masao Yamaguchi  Hiromasa Yamamoto  Joji Ohshita 《应用聚合物科学杂志》2009,112(1):496-504

Three adamantane derivatives substituted by epoxy groups, 1,3‐bis(glycidyloxy)adamantane ( 2a ), 5,7‐dimethyl‐1,3‐bis(glycidyloxy)adamantane ( 2b ), 1,3,5‐tris(glycidyloxy)adamantane ( 2c ), were synthesized from the corresponding adamantanediol or triol in good yields. These three epoxy compounds were polymerized with an acid anhydride, and the heat resistance of the resulting resins was evaluated. The resin prepared from 2c exhibited high heat resistance with the glass transition temperature (T_g) of 208°C and low degree of coloring by heating. The epoxy compounds were also found to be potentially useful as the precursors of high heat‐resistant resins by thermal homopolymerization. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

    

Masayuki Yamaguchi  Takashi Wakabayashi  Taichi Kanoh 《应用聚合物科学杂志》2008,107(4):2665-2670

The optical properties and rheological properties were studied for binary reactive blends composed of poly(ethylene terephthalate‐co‐ethylene isophthalate) [P(ET–EI)] and a styrene–acrylate based copolymer with glycidyl functionality. The blade rotation speed in the internal mixer greatly affected the structure and properties for the blend system. Intensive mixing at a high rotation speed enhanced the optical transparency because of the reduced particle size of the dispersed phase. The graft copolymer generated by the reaction between P(ET–EI) and the modifier was responsible for the fine morphology. Furthermore, the copolymer also enhanced the elastic nature in the molten state because it acted as a long‐chain branched polymer. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008  相似文献   

    

Gérard Palavit  Cyrille Mercier  Lionel Montagne  Michel Drache  Yoshihiro Abe 《Journal of the American Ceramic Society》1998,81(6):1521-1524

The chemical reactions between P₂O₅-ZnO-H₂O ultraphosphate glasses and water were characterized between room temperature and 500°C, using thermogravimetry, differential scanning calorimetry, X-ray diffraction, and ³¹P nuclear magnetic resonance. Water adsorption and hydrolysis reactions of the glass leads to the formation of H₃PO₄ and crystalline ZnH₂P₂O₇ below 200°C. The rate of water adsorption increases, owing to the hygroscopicity of the hydrolysis products of the glass. Devitrification occurs at 250°C via surface reactions. The microstructure of the devitrified glass consists of crystalline Zn₂P₄O₁₂ and a liquid phase containing hydrolysis products of P₂O₅ like metaphosphoric acid (HPO₃) _n. Devitrification is finally followed by water desorption at higher temperatures.  相似文献   

    

Hideaki Takahashi  Toshio Kasai  Kizashi Yamaguchi  Hansjuergen H. Loesch 《Israel journal of chemistry》1997,37(4):359-365

Three dimensional (3D) wavepacket simulation on the H atom scattering is carried out for a full reaction of CF₃H + Ar(³P) → CF₃* + H + Ar for the H-end orientation since our previous study on the 2D wavepacket simulation showed a quantum interference effect only for collisions at the H-end of CF₃H. We treat the present 3D wavepacket simulation in a time-dependent SCF (TDSCF) scheme, which enables us to reduce 3D to a coupled two and one dimensional (2D+1D) problem. The initial wavepacket of CF₃H is prepared in the lowest rotational state, i.e., |JKM > = |111>. The calculated snapshots of the scattered wavepacket for the Fiend orientation show a clear quantum interference effect again in the angular distribution of the product H atom due to the so-called one-atom cage effect on the heavy-light-heavy collision configuration. Thus the present simulation suggests that a continuous wave character of the wavepacket would be responsible for such a relatively clear interference effect in the full reaction, unlike a blurred interference effect with a pulse-type of wavepacket excitation in the half reaction.  相似文献   

    

T. Nakano  K. Suzuki  T. Yamaguchi 《The Journal of Adhesion》1994,46(1):131-144

The RuO₂-glass interaction has been studied by analyzing the growth of RuO₂ particles in glasses. The size of RuO₂ particles was determined by TEM and X-ray line broadening. The RuO₂/glass interfacial energy was evaluated by spreading and penetration experiments.

Changes in size and shape of RuO₂ particles indicated that coarsening proceeded by the diffusion-controlled dissolution-precipitation process. The growth rate of RuO₂ particles at temperatures giving the same viscosity was dependent on the glass composition. Kinetics of the Ostwald ripening and values of glass surface energy implied that the solubility of RuO₂ in glass is a critical factor. Results indicated that the solubility of RuO₂ in glass decreases with increasing PbO content and with increasing SiO₂ substitution for B₂O₃. Dissolution of Al₂O₃ from substrate retarded the Ostwald ripening.  相似文献   

    

Michio Inagaki  Yutaka Kaburagi  Yoshihiro Hishiyama 《Advanced Engineering Materials》2014,16(5):494-506

  相似文献   

    

S J Denholme  H Okazaki  S Demura  K Deguchi  M Fujioka  T Yamaguchi 《Science and Technology of Advanced Materials》2014,15(5)

  相似文献   

    

Kinya Iwatsuka  Katsuhiro Inada  Hiroki Ueoka  Tadashi Otsuka  Masaki Maeda  Masazumi Yamaguchi 《Drug development and industrial pharmacy》2015,41(9):1526-1531

Context: Ophthalmic solutions are usually filled in a plastic bottle due to its durability and disposability. In Japan, photostability is one of the concerns for the quality control because an eye drop bottle must be a transparent container.

Objective: The present work studied the effect of textured eye drop bottles on its light blocking to improve the photostability of ophthalmic solutions.

Materials and methods: We investigated the photostability of Pranoprofen ophthalmic solution filled in a variety of textured eye drop bottles. Pranoprofen content was analyzed by high-performance liquid chromatography and surface structure of textured eye drop bottles was evaluated by transmittance, calculated average roughness (Ra) and haze intensity.

Results: We observed that eye drop bottle which had greater than Ra value of 1.0?µm and haze intensity 62% clearly showed photostability improvement.

Conclusions: This report is the first one which shows that photostability of ophthalmic solution is improved by using textured eye drop bottle. Moreover, this approach is a simple and effective method to improve the photostability. This method is available for not only various ophthalmic applications but also other liquid pharmaceuticals or food products.  相似文献   

    

T. Yasuda  I. Yamaguchi  T. Yamamoto 《Advanced materials (Deerfield Beach, Fla.)》2003,15(4):293-296

  相似文献