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641.
Effect of ammonium polyphosphate and fillers on flame retardant and mechanical properties of recycled PET injection molded 下载免费PDF全文
Supaphorn Thumsorn Takanori Negoro Wiranphat Thodsaratpreeyakul Hiroyuki Inoya Masayuki Okoshi Hiroyuki Hamada 《先进技术聚合物》2017,28(8):979-985
Ammonium polyphosphate (APP) and inorganic fillers were applied for improving flame retardancy and mechanical performance of recycled poly(ethylene terephthalate) (RPET). RPET was compounded with 5–10 wt% of talc and glass bead using twin screw extruder then were injection molded with 2 wt% of APP. The effects of fillers contents and APP on properties and flame retardancy of RPET composites were investigated. The incorporation of talc and glass bead as well as the adding of APP significantly improved tensile and flexural modulus of RPET composites. Scanning electron microscope micrographs indicated good distribution of talc, while glass bead was agglomerated on the RPET matrix. Flame‐retardant property of neat RPET and the RPET composites revealed V‐2 of UL‐94 flammability rating. It can be noted that the composites were less dripping because of the synergistic effect of adding talc and glass bead with APP. From thermogravimetric analysis results, larger of residual char contents and lower values of the activation energy were considered for enhancing flame retardancy in the RPET composites. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
642.
Takanori Hatano Brad M. Rosen Virgil Percec 《Journal of polymer science. Part A, Polymer chemistry》2010,48(1):164-172
The single‐electron transfer living radical polymerization (SET‐LRP) of vinyl chloride (VC) initiated with CHBr3 in dimethylsulfoxide (DMSO) at 25 °C was investigated using Cu(0) powder and Cu(0) wire as the catalyst. It was determined that living kinetics and high conversion are achieved only through the proper calibration of the ratio between Cu(0) and TREN and the concentration of VC in DMSO. For both Cu(0) powder and Cu(0) wire, optimum conversion was achieved with higher levels of TREN than reported in earlier preliminary reports and under more dilute conditions. Using these conditions, 85+% conversion of VC could be achieved with Cu(0) powder and wire to produce white poly(vinyl chloride) (PVC) with Mn = 20,000 and Mw/Mn = 1.4–1.6 in 360 min. The use of Cu(0) wire provides the most effective catalytic system for the LRP of PVC allowing for simple removal and recycling of the catalyst. In the Cu(0) wire‐catalyzed SET‐LRP of VC, the consumption of Cu(0) was monitored as a function of conversion. From these studies, it is evident that the catalyst can be recycled extensively before significant exchange of Cu(0) into Cu(II)X2 and change in catalyst surface area is observed. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 164–172, 2010 相似文献
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Hidetoshi Kawai Takanori Suzuki Masakazu Ohkita Takashi Tsuji 《Angewandte Chemie (International ed. in English)》1998,37(6):817-819
Benzene rings severely bent and closely stacked face-to-face are revealed in the crystal structure of the [1.1]paracyclophane derivative 1 , which could be isolated thanks to the kinetic stabilization provided by the steric shielding of the bridgehead sites by the substituents. 相似文献
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Kazuaki Ito Takanori Ohta Yoshihiro Ohba Tyo Sone 《Journal of heterocyclic chemistry》2000,37(1):79-85
Chiral bishomodiazacalix[4]arenes containing amino acid residues were prepared. The 1H and 13C nmr spectra indicated that the macrocycles preferably adopted a cone conformation, which suggested that the cyclophane moiety was in a chiral twisted form. Circular dichroism spectra supported the existence of the chirality of the cyclophane unit, and showed that intramolecular hydrogen bonding plays an important role in the transmission of the chirality from the amino acid residues to the cyclophane moiety. Macrocycles bearing a tyrosine residue have a π‐base cavity large enough to include the ammonium ion, and can serve as a shift reagent for the racemic ammonium ions upon complexation during a 1H nmr analysis. 相似文献
648.
Toshihide Tsuda Eiji Yamamoto Akira Babazono Yoshio Mino Yoshiki Kishi Norio Kurumatani Takanori Ogawa Hideyasu Aoyama 《应用有机金属化学》1994,8(3):237-244
Survival analysis was used to analyze follow-up data on an arsenic-poisoned area, identified in 1959, in order to assess the effect of arsenic on survival time. The subjects were 443 residents of Namiki-cho, Nakajo-machi, Niigata Prefecture, Japan, who ingested well water contaminated with arsenic between 1955 and 1959. Their exposure to arsenic was only by ingestion of well water. We observed this historical cohort from October 1959 to February 1992. Survival time was calculated in two ways: from 1959 (the end of exposure) until death or until 1992 (the termination of follow-up); or from birth until death or until 1992. The entire cohort was divided into two groups according to the arsenic concentration measured in the wells in 1959. Different survival curves of the two were drawn using the Kaplan–Meier method. The lifetime survival curves indicate that the lifetimes of arsenic-exposed residents were significantly shorter than that of the low-dose exposure group or of unexposed residents. From the differences in the estimated lifetime survival curves, the effect of arsenic on the mortality of the residents can be inferred. 相似文献
649.
Takanori Tanaka 《Tetrahedron letters》2005,46(30):4989-4991
Nitrobenzene was found to work as an efficient hydrogen acceptor in the oxidation of allylic alcohols to give the corresponding enones in high yields. 相似文献
650.
The 1,3-dipolar cycloaddition reactivity and regioselectivity of methyleneadamantane 1, ethyl adamantylideneacetate 7a, adamantylideneacetonitrile 7b and ω-methoxymethyleneadamantane 7c with substituted benzonitrile oxides 3a-i were calculated by CNDO/2 method using the perturbation equation derived by Klopman and Salem. The calculation predicted an exclusive formation of adamantan - 2 - spiro - 5' - 3' - aryl - Δ2' - isooxazoline 4a-i in the reactions of 1, 7a and 7b with 3a-i, and a formation of 67–69:33-31 mixture of 4a-i and isomeric 5a-i in the reaction of 7c with 3a-i. The predicted exclusive formation of 4a-i were experimentally observed in the reactions of 1,7a and 7b with 3a-i generated from 2a-i with Et3N or thermally, but the reaction of 7c with 3a did not afford the corresponding adducts. A considerably higher reactivity of CN triple bond than CC double bond was observed in the reaction of 7b with 3a and 1,2,4-oxadiazole derivative 11 was obtained as the major product. 相似文献