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991.
气相色谱法测定大气中的丙烯酸及其酯类化合物 总被引:1,自引:0,他引:1
用活性炭采集大气样品,OV-101(30m×0.32 mm i. d.)弹性石英毛细管柱分离丙烯酸和3种丙烯酸酯类化合物,氢火焰离子化检测器测定,建立了气相色谱法测定大气中丙烯酸及其酯类化合物的方法。该方法有较宽的线性范围,相关系数达到0.996以上,相对标准偏差为3.16%~5.83%,回收率为84.4%~95.4%,检出限为0.003~0.03 mg/m~3(采样体积为20L)。 相似文献
992.
Kazumasa Funabiki Naoyuki Sugiyama Ji-Ye Jin Yasutake Kato Masaki Matsui 《Journal of fluorine chemistry》2006,127(2):257-262
Four kinds of ring-fluorinated fluoresceins and sulfofluorescein from tetrafluororesorcinol and/or tetrafluorophthalic anhydride have been synthesized and the photochemical properties of the zinc oxide nanocrystalline electrode sensitized by the ring-fluorinated fluoresceins were investigated. 相似文献
993.
Interpolymer complexes of poly(acrylic acid) with poly(2-hydroxyethyl acrylate) in aqueous solutions
Grigoriy?A.?MunEmail author Vitaliy?V.?Khutoryanskiy Gulnara?T.?Akhmetkalieva Sergey?N.?Shmakov Artem?V.?Dubolazov Zauresh?S.?Nurkeeva Kinam?Park 《Colloid and polymer science》2004,283(2):174-181
Complexes formed from poly(acrylic acid) and poly(2-hydroxyethyl acrylate) were studied in aqueous solutions by viscometric, turbidimetric, FTIR spectroscopic, and thermogravimetric analysis methods. The formation of interpolymer complexes stabilized by hydrogen bonds was observed. It was found that the compositions of these interpolymer complexes are strongly dependent on the concentration of polymers, the order of mixing the solutions, and the pH. It was demonstrated that the complexation ability of poly(2-hydroxyethyl acrylate) is relatively low compared to other known nonionic water-soluble polymers. However, it can be significantly increased via hydrophobic modification of the poly(acrylic acid) using cetyl pyridinium bromide. 相似文献
994.
995.
996.
UV Curable Hard Transparent Hybrid Coating Materials on Polycarbonate Prepared by the Sol-Gel Method
Gilberts J. Tinnemans A.H.A. Hogerheide M.P. Koster T.P.M. 《Journal of Sol-Gel Science and Technology》1998,11(2):153-159
UV curable, hard, transparent inorganic/organic composites with covalent links between the inorganic and the organic networks were prepared by the sol-gel method. These hybrid coating materials were synthesized using a commercially available, acrylate end-capped polyester or polyurethane oligomeric resin (EBC80, EBC284), hexanedioldiacrylate (HDDA) as a reactive solvent, 3-(trimethoxysilyl)propoxymethacrylate (TMSPM) as a coupling agent between the organic and inorganic phase, and a metal alkoxide, tetraethylorthosilicate (TEOS). The materials were applied on primer or oxygen plasma pretreated polycarbonate sheets and UV cured, followed by a thermal treatment to give a transparent coating with a good adhesion and abrasion resistance. The high transmission and the thermogravimetric behavior indicate the presence of a nanoscale hybrid composite, as is confirmed by SAXS and TEM measurements. In a Taber Abrasion Test, uncoated polycarbonate sheets exhibit a 48% decrease in light transmittance at 600 nm after 300 wear cycles, whereas the EBC80 hybrid coating system containing 9 wt% SiO2 (EBC80/25Si) shows only 28% decrease in light transmittance. A maximal improvement of the abrasion resistance is achieved when 23 wt% SiO2 is incorporated (EBC80/60Si, EBC284/60Si) with only 20% decrease in light transmittance. The abrasion resistance of glass is not yet encountered. For optimal results, it is essential that the rate of condensation of the silanol groups is sufficiently high to form a dense three-dimensional network. 相似文献
997.
Polymer coated quartz crystal microbalance (QCM) sensor based on the frequency shifts due to the adsorption of compounds at the surface of modified quartz crystal electrode is an effective method for detection of sarin (GB) which is a highly toxic nerve warfare agent. A new fluorosiloxane polymer has been synthesized through 6 steps from trifluoromethyl benzene. The synthesis was achieved from trifluoromethyl benzene through nitration, hydrogenation. The obtained m-nitrotrifluoromethyl aniline was treated with NANO2, and then hydrolyzed to m-nitrotrifluoromethyl phenol, m-nitrotrifluoromethyl phenol was reacted with allyl bromide to the ether product. The product was rearranged by Claisen rearrangement, and then reacted with polymethylhydrosiloxane under catalyst of Pt/DVTMS. The fluorosiloxane polymer can be obtained. The polymer has been successfully used as QCM coating material 相似文献
998.
部分水解聚(丙烯酸甲酯-乙酸乙烯酯-甲基丙烯酸甲酯)高吸水性树脂的合成及结构研究 总被引:4,自引:0,他引:4
研究了部分水解聚(丙烯酸甲酯-乙酸乙烯酯-甲基丙烯酸甲酯)高吸水性树脂-HP(MA-VAc-MMA)的合成,讨论了聚合,水解工艺条件对该树脂吸水(液)性能的影响,用红外,X-射线衍射和电子衍射等方法测定了共聚物的结构。结果表明,HP(MA-VAc-MMA)树脂的吸水能力为:去离子水837ml/g、自来水440ml/g、0.9%NaCl溶液ml/g、合成血119ml/g、合成尿73ml/g;该树脂具有结晶结构,与PVC树脂共混可制备吸水膨胀性材料。 相似文献
999.
1000.
Reza Arshady Fereidoon Fallah 《Journal of polymer science. Part A, Polymer chemistry》1992,30(8):1705-1716
A new class of “amphiphilic” copoly(styrene-acrylamide)s of potential interest for peptide synthesis is described. As examples of the new polymers, those carrying nitrophenol or piperazine functionality were used for model reactions in peptide synthesis, and were found to be substantially more efficient than similar reagents derived from polystyrene, polydimethylacrylamide or silica gel. Due to their amphiphilic structure, the new resins have general substrate compatibility and are permeated by all of the commonly used solvents, including toluene and ethyl acetate on the one hand, through dimethylformamide, to dimethylsulfoxide and water on the other. The improved performance of the new polymers is attributed to their alternating amphiphilic structure and favorable polymer–solvent–substrate interactions. © 1992 John Wiley & Sons, Inc. 相似文献