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81.
Koji Honda Ikuo Yamamoto Masamichi Morita Hiroki Yamaguchi Hiroshi Arita Ryohei Ishige Yuji Higaki Atsushi Takahara 《Polymer》2014
The effect of α-substituent on the molecular motion and wetting behavior of poly{2-(perfluorobutyl)ethyl acrylate} [PFA-C4], poly{2-(perfluorobutyl)ethyl methacrylate} [PFMA-C4], poly{2-(perfluorobutyl)ethyl α-fluoroacrylate} [PFFA-C4], and poly{2-(perfluorobutyl)ethyl α-chloroacrylate} [PFClA-C4] films were characterized by dynamic contact angle measurement, lateral force microscopy (LFM), wide angle X-ray diffraction (WAXD), and X-ray photoelectron spectroscopy (XPS). WAXD of oriented PFClA-C4 fiber suggested the presence of rod-like chain due to the presence of bulky α-substituent. The glass transition temperature (Tg) of PFFA-C4 and PFClA-C4 were well above the room temperature. The water repellencies of PFFA-C4 and PFClA-C4 were as high as that of PFMA-C4 and their oil repellency of PFFA-C4 and PFClA-C4 was higher than the PFMA-C4. This result was originated from the low main chain mobility of PFFA-C4 and PFClA-C4 due to the presence of bulky α-substituents. The effect of molecular motion on water repellency was clarified by the results of temperature dependence studies of dynamic contact angle, LFM, and surface chemical composition measured by XPS. 相似文献
82.
Naohiro Gotoh Shino Miyake Hiroko Takei Kumi Sasaki Saori Okuda Michitaka Ishinaga Shun Wada 《Food Analytical Methods》2011,4(4):525-530
We developed a simple method for quantification of the peroxide value (PV) in colored lipids on the basis of the reaction
between triphenylphosphine (TPP) and oxidized oil to afford triphenylphosphineoxide (TPPO). Diphenylphosphineoxide (DPPO)
was employed as internal standard. The formed TPPO was analyzed by high-pressure liquid chromatography–UV spectroscopy with
absorption at 260 nm. The conditions that gave the highest correlative calibration curve between the peak area on the chromatogram
and peroxide value were identified: the optimum TPP–oxidized oil mix ratio, reaction temperature, and reaction time were found
to be 2:1, 40 °C, and 30 min, respectively. Linear calibration curves, passing through the origin, were obtained for PV versus
TPPO and TPPO versus DPPO. The quantification limit for this method was 2.01 pmol hydroperoxyl group, which corresponds to
a PV value of 0.2 meq/kg in a 10-mg oil sample. This method was used to measure the PV in colored fats and oils or lipids
extracted from dark meat and processed food containing a coloring agent. Though the official method could not measure the
PVs in the colored lipids, the method proposed here, which uses an inexpensive chemical reagent and machine, could. The developed
method could play an important role for food quality control. 相似文献
83.
Compression molding and melt‐spinning of the blends of poly(lactic acid) and poly(butylene succinate‐co‐adipate)
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Weraporn Pivsa‐Art Sommai Pivsa‐Art Kazunori Fujii Keiichiro Nomura Kiyoaki Ishimoto Yuji Aso Hideki Yamane Hitomi Ohara 《应用聚合物科学杂志》2015,132(16)
Poly(lactic acid) (PLA) is a biobased polymer made from biomass having high mechanical properties for engineering materials applications. However, PLA has certain limited properties such as its brittleness and low heat distortion temperature. Thus, the aim of this study is to improve toughness of PLA by blending with poly(butylene succinate‐co‐adipate) (PBSA), the biodegradable polymer having high toughness. Polymer blends of PLA and PBSA were prepared using a twin screw extruder. The melt rheology and the thermal property of the blends were examined. Further the blends were fabricated into compression molded parts and melt‐spun fiber and were subjected to tensile and impact tests. When the PBSA content was low, PBSA phase was finely dispersed in the PLA matrix. On the other hand, when the PBSA content was high, this minor phase dispersed as a large droplet. Mechanical properties of the compression molded parts were affected by the dispersion state of PBSA minor component in PLA matrix. Impact strength of the compression molded parts was also improved by the addition of soft PBSA. The improvement was pronounced when the PBSA phase was finely dispersed in PLA matrix. However, the mechanical property of the blend fibers was affected by the postdrawing condition as well as the PBSA content. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41856. 相似文献
84.
85.
To understand the adsorption properties of a styrene–divinylbenzene copolymer functionalized with N,N,N-trimethylglycine, AMP03, the adsorption behaviours for platinoid ions (Ru(III), Rh(III) and Pd(II)) were examined. Furthermore, we performed adsorption experiments using sample solutions by adding triethylamine, thiourea and N,N,N-trimethylglycine. Based on the adsorption data obtained in this study, we performed chromatographic experiments. The results indicated that all platinoid ions in the feed solution completely adsorbed on AMP03, and almost 80% of the adsorbed platinoid ions were recovered. These results show that AMP03 has the potential to recover Ru(III), Rh(III) and Pd(II) from high-level liquid waste. 相似文献
86.
Use of polyethylene films photografted with 2‐(dimethylamino)ethyl methacrylate as a potential adsorbent for removal of chromium (VI) from aqueous medium
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Hiromichi Asamoto Yuji Kimura Yohei Ishiguro Hiroaki Minamisawa Kazunori Yamada 《应用聚合物科学杂志》2016,133(18)
A new polymeric adsorbent material based on polyethylene (PE) was prepared by photografting of 2‐(dimethylamino)ethyl methacrylate (DMAEMA) as a positively chargeable monomer to a PE film. The effects of the experimental parameters, such as the pH value, temperature, and grafted amount on adsorption of chromium(VI) (Cr(VI)) ions were investigated for the DMAEMA‐grafted PE (PE‐g‐PDAMEMA) films. The maximum adsorption capacity was obtained at the initial pH value of 3.0 for a PE‐g‐PDMAEMA film with 1.8 mmol/g and the maximum adsorption capacity obtained was higher than or compatible to those of many of the other polymeric adsorbents prepared for Cr(VI) ions. The adsorption kinetics obeyed the mechanism of the pseudo‐second order kinetic model and adsorption of Cr(VI) ions on PE‐g‐PDMAEMA films was well expressed by the Langmuir isotherm model. A high Langmuir adsorption constant suggests that the adsorption of Cr(VI) ions occurs between protonated dimethylamino groups and ions mainly through the electrostatic interaction. Cr(VI) ions adsorbed were successfully desorbed from a PE‐g‐PDMAEMA film in solutions of NaCl, NH4Cl, NH4Cl containing NaOH, and NaOH and a PE‐g‐PDMAEMA film was regenerated and repeatedly used for adsorption of Cr(VI) ions without appreciable loss in the adsorption capacity. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43360. 相似文献
87.
Characterization of alternative plasticizers in poly(vinyl chloride) sheets for blood containers
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Yuji Haishima Tsuyoshi Kawakami Chie Fukui Akito Tanoue Toshiyasu Yuba Satoru Ozono Hidehumi Kumada Kaoru Inoue Tomomi Morikawa Miwa Takahashi Ayano Fujisawa Kayo Yamasaki Yusuke Nomura Kazuo Isama Ung‐il Chung Kumiko Ogawa Shingo Niimi Midori Yoshida 《乙烯基与添加剂工艺杂志》2016,22(4):520-528
This study aimed to optimize the ratio of dioctyl 4‐cyclohexene‐1,2‐dicarboxylate (DOTH) and di‐isononyl‐cyclohexane‐1,2‐dicarboxylate (DINCH®) for use as plasticizers in poly(vinyl chloride) (PVC) sheets. We also evaluated the biological safety of DOTH for its potential to be part of a safe PVC‐based blood container. The suppression of hemolysis in mannitol‐adenine‐phosphate / red cell concentrates (MAP/RCC) with DOTH/(DINCH®‐PVC) sheets and the elution of plasticizers from the sheets increased with higher DOTH compositions. The properties of the PVC sheet containing DOTH and DINCH® in the ratio of 25:33 parts against PVC 100 parts as a weight were almost identical to the PVC sheet made of di(2‐ethylhexyl) phthalate. From a subchronic toxicity test, DOTH did not show any adverse effects on all organs, including the testes, epididymis, liver, and kidneys. The no‐observed‐adverse‐effect level was 300 mg/kg body weight/day in a rat. These results suggest that DOTH/DINCH® (25:33) is a promising candidate for the replacement of di(2‐ethylhexyl) phthalate in blood containers. J. VINYL ADDIT. TECHNOL., 22:520–528, 2016. © 2015 Society of Plastics Engineers 相似文献
88.
以单水氢氧化锂和四氧化三锰为原料,用固相法制备出锂离子筛锰酸锂,改变n(锂)/n(锰)之后,用同样的方法制备出另一物质Li1.33Mn1.67O4,经硝酸洗涤脱锂后制备了锂离子筛MnO2·0.4H2O。测定了酸洗时前驱体的锂洗脱率、锰溶损率,研究了锂离子筛MnO2·0.4H2O的饱和吸附量、稳定性、pH滴定曲线。结果表明,前驱体Li1.33Mn1.67O4经硝酸二次酸洗后,锂洗脱率和锰溶损率分别为62.7%和6.0%。在含0.1 mol/L氢氧化钠和10 mmol/L氯化锂的溶液中,经固相法制备的锂离子筛MnO2·0.4H2O对锂离子的饱和吸附量达到24.6 mg/g,并且具有较好的稳定性,pH滴定曲线表明锂离子筛对锂离子具有很好的选择性。 相似文献
89.
Shi‐Kuan Sun Ya‐Ru Zhang Yuji Masubuchi Teruki Motohashi Shinichi Kikkawa 《Journal of the American Ceramic Society》2014,97(4):1023-1027
The maintaining of the chemical composition and electrical insulativity of SrTaO2N ceramics was investigated during sintering and annealing, using powders prepared by the nitridation of Sr2Ta2O7. Due to the low thermal stability of SrTaO2N, the partial loss of SrO and nitrogen induced the formation of a TaO0.9 impurity after heat‐treating at above 1100°C. The sintering additive SrCO3 and postannealing in NH3 were employed to compensate for the loss of SrO and nitrogen to obtain ceramics with the original chemical composition. The as‐sintered SrTaO2N ceramics with various relative density (RD) were annealed in NH3 to observe the recovery of color and electrical insulativity. It was found that the inner part of the well‐sintered samples with RD = 95.1% could not be recovered by annealing, and continued to exhibit semiconducting behavior and a black color. On the other hand, for the as‐sintered SrTaO2N ceramics with RD < 84%, both the nitrogen content and electrically insulating behavior were completely recovered after annealing. The postannealed SrTaO2N ceramics (RD = 83.3%) possessed a relatively large dielectric constant of 450 with a low dielectric loss of less than 0.1 at 100 Hz, almost independent of frequency and temperature. 相似文献
90.
Dynamic mechanical properties of three‐component composites (acrylic polymer/epoxy/SiO2) in the glass‐transition region
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Hideyuki Uematsu Takashi Nishimoto Shuichi Tanoue Yoshiyuki Iemoto Yuji Aoki Masataka Sugimoto Kiyohito Koyama 《应用聚合物科学杂志》2014,131(13)
In previous studies, we reported the linear and nonlinear rheological properties of three‐component composites consisting of acrylic polymer (AP), epoxy resin (EP), and various SiO2 contents (AP/EP/SiO2) in the molten state. In this study, the dynamic mechanical properties of AP/EP/SiO2 composites with different particle sizes (0.5 and 8 μm) were investigated in the glass‐transition region. The EP consisted of three kinds of EP components. The α relaxation due to the glass transition shifted to a higher temperature with an increase in the volume fraction (?) for the AP/EP/SiO2 composites having a particle size of 0.5 μm, but the α relaxation scarcely shifted for the composite having a particle size of 8 μm as a general result. This result suggested that the SiO2 nanoparticles that were 0.5 μm in size adsorbed a lot of the low‐glass‐transition‐temperature (Tg) component because of their large surface area. The AP/SiO2 composites did not exhibit a shift in Tg; this indicated that the composite did not adsorb any component. The modulus in the glassy state (E′g) exhibited a very weak &phis; dependence for the AP/EP/SiO2 composites having particle sizes of 0.5 and 8 μm, although E′g of the AP/SiO2 composites increased with &phis;. The AP/EP/SiO2 composites exhibited a peculiar dynamic mechanical behavior, although the AP/SiO2 composites showed the behavior of general two‐component composites. Scanning electron microscopic observations indicated that some components in the EP were adsorbed on the surface of the SiO2 particles. We concluded that the peculiar behavior of the AP/EP/SiO2 composites was due to the selective adsorption of the EP component. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40409. 相似文献