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1.
The α,ω-diiodoperfluorooctane is added to undecyl-10-en-1-ol through AIBN initiation yielding the monoadduct in good yield (1,2-dichloroethane, 52%). This is added to N-allylphthalimide (AIBN initiation, 1,2-dichloroethane, 81%). The resulting diiodo compound is hydrodeiodinated with Bu3SnH (toluene, 70%) and the alcohol function is converted to thioacetate through the Mitsunobu reaction (PPh3, DIAD, THF, 75%). The two protecting groups, phthalimide and thioacetate, are removed with hydrazine to give the expected amino terminated semifluorinated long-chain alkanethiol (ethanol, 80%). This compound has been designed in order to form mixed fluorinated self-assembled monolayers (SAMs) with semifluorinated long-chain alkanethiol giving access to a new platform system for biosensors. Similar results are reported starting from the α,ω-diiodoperfluorohexane.  相似文献   

2.
Two sets of styrene‐based semifluorinated block copolymers, one with a perfluoroether pendant group and another with a perfluoroalkyl group, were synthesized by atom transfer radical polymerization. Microphase separation of the block copolymers was established by small‐angle X‐ray scattering and differential scanning calorimetry (DSC). DSC measurements also showed that the perfluoroether‐based polymer had a low glass‐transition temperature (?44 °C). Contact‐angle measurements indicated that the semifluorinated block copolymers had low surface energies (ca. 13 mJ/m2). These materials hold promise as low‐surface‐energy additives or surfactants for supercritical CO2 applications. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 853–861, 2004  相似文献   

3.
The goal of the investigation presented here was to evaluate the influence of semifluorinated side chains on the bulk structure and the surface properties of polysulfones with different chain structure. Thus, segmented block copolymers consisting of polysulfone and semifluorinated aromatic polyester segments as well as polysulfones having semifluorinated side chains randomly distributed over the polymer backbone were synthesized and characterized. Oxydecylperfluorodecyl side chains were used because of their strong tendency for self-organization. The influence of the chain architecture on the self-organization as well as on the surface properties, particularly the wetting behavior, was examined. It could be shown that despite of the higher self-organizing tendency of block copolymers the surface properties of both polymer types are comparable and depend only on the concentration of side chains.  相似文献   

4.
A fluorinated diamine monomer containing flexible ether linkage and bulky trifluoromethyl substituents, namely, bis(4‐amino‐2‐trifluoromethylphenyl) ether (a), is employed to react with nonfluorinated 1,4‐bis(3,4‐dicarboxyphenoxy) benzene dianhydride (3) and CF3‐free 2,2‐bis[4‐(3,4‐dicarboxyphenoxy)phenyl] propane dianhydride (4), respectively, to prepare 2 novel soluble and optically transparent semi‐fluorinated poly (ether imide)s (PEIs; 3a and 4a). Compared with the corresponding PEIs based on nonfluorinated 4,4′‐diaminodiphenyl ether (b) and CF3‐free pyromellitic dianhydride (5), the novel semifluorinated PEIs 3a and 4a not only display better solubility in some organic solvents and higher optical transparency with cutoff absorption wavelength (λ0) below 370 nm but also maintain outstanding mechanical properties and thermal stability. 3a and 4a have tensile strength beyond 80 MPa and possess glass‐transition temperatures (Tg) beyond 210°C, coupled with the temperatures of 5% weight loss (T5%) exceeding 500°C. It is also found that 3a and 4a exhibit contact angles against water beyond 110° and water absorptions below 0.8% together with dielectric constants less than 3.2.  相似文献   

5.
卿胜波  黄卫  颜德岳 《化学学报》2005,63(7):667-670
采用5-磺酸钠间苯二甲酸、双(苯甲酸)六氟丙烷与3,3',4,4'-四氨基联苯在多聚磷酸中通过共缩聚反应, 合成了一系列磺化度(定义为100个重复单元中所含的磺酸基个数, SD)可控的含氟磺化聚苯并咪唑(sPBI), 并利用红外光谱、核磁共振、凝胶色谱和热失重分析等手段对其结构、分子量与热稳定性进行了表征, 还考察了其溶解性和成膜性. 结果表明, sPBI的数均分子量(Mn)为61300~86000, 多分散指数介于1.96~2.34之间, 并且sPBI具有良好的成膜性和优异的热稳定性能, 其5%和10%热失重对应温度均随着SD的增加而有所提高, 在SD为70%时分别为549和576 ℃. 此类聚合物在质子交换膜材料方面具有一定的应用前景.  相似文献   

6.
A new facile preparative method for the synthesis of organocyclosiloxanes is reported. Ring closure of the dichlorosilanes with NaHCO 3 and pyridine gave mixture of organocyclosiloxanes with cyclotrisiloxane as a main product.  相似文献   

7.
The surface energy of a semifluorinated salicylaldimine liquid crystal has been characterised by inverse gas chromatography over the temperature range 303 to 323 K using n-alkanes, tetrahydrofurane, dichloromethane, chloroform, acetone and ethyl acetate molecular probes. The dispersive component of the surface free energy of the adsorbent surface studied was calculated according to the approaches of Fowkes and Dorris–Gray in the infinite dilution region. The specific free energy, enthalpy and entropy of adsorption of polar probes on the liquid crystal were determined. The values of the specific enthalpy of adsorption were correlated with both the donor and the acceptor numbers of the probes to quantify the acidic and the basic parameters of the liquid crystal surface. The surface of the semifluorinated salicylaldimine liquid crystal was found to show a basic nature, which determined the nature of its interaction with the polar probes.  相似文献   

8.
A straight forward synthesis and efficient introduction of fluoromethyl group in nitrogen heterocycles is reported. Starting from the respective NH heterocycles fluoromethylation is performed with fluoroiodomethane and proceeds under mild reaction conditions. Structural information of monofluoromethylated nitrogen-containing cyclic compounds containing the biologically active NCH2F moiety are reported. The particularly impressively change of physical and spectroscopic properties by the substitution of a methyl group by a monofluoromethyl group is discussed based on these examples.  相似文献   

9.
含氟二芳基取代乙炔的合成   总被引:2,自引:0,他引:2  
含氟二芳基取代乙炔的合成;ZnCl2/SiO2;含氟芳基取代乙炔;合成  相似文献   

10.
The synthesis, micelle formation, and bulk properties of semifluorinated amphiphilic poly(ethylene glycol)‐b‐poly(pentafluorostyrene)‐g‐cubic polyhedral oligomeric silsesquioxane (PEG‐b‐PPFS‐g‐POSS) hybrid copolymers is reported. The synthesis of amphiphilic PEG‐b‐PPFS block copolymers are achieved using atom transfer radical polymerization (ATRP) at 100 °C in trifluorotoluene using modified poly(ethylene glycol) as a macroinitiator. Subsequently, a proportion of the reactive para‐F functionality on the pentafluorostyrene units was replaced with aminopropylisobutyl POSS through aromatic nucleophilic substitution reactions. The products were fully characterized by 1H‐NMR and GPC. The products, PEG‐b‐PPFS and PEG‐b‐PPFS‐g‐POSS, were subsequently self‐assembled in aqueous solutions to form micellar structures. The critical micelle concentrations (cmc) were estimated using two different techniques: fluorescence spectroscopy and dynamic light scattering (DLS). The cmc was found to decrease concomitantly with the number of POSS particles grafted per copolymer chain. The hydrodynamic particle sizes (Rh) of the micelles, calculated from DLS data, increase as the number of POSS molecules grafted per copolymer chain increases. For example, Rh increased from ~60 nm for PEG‐b‐PPFS to ~80 nm for PEG‐b‐PPFS‐g‐POSS25 (25 is the average number of POSS particles grafted copolymer chain). Static light scattering (SLS) data confirm that the formation of larger micelles by higher POSS containing copolymers results from higher aggregation numbers (Nagg), caused by increased hydrophobicity. The Rg/Rh values, where Rg is the radius of gyration calculated from SLS data, are consistent with a spherical particle model having a core‐shell structure. Thermal characterization by differential scanning calorimetry (DSC) reveals that the grafted POSS acts as a plasticizer; the glass transition temperature (Tg) of the PPFS block in the copolymer decreases significantly with increasing POSS content. Finally, the rhombohedral crystal structure of POSS in PEG‐b‐PPFS‐g‐POSS was verified by wide angle X‐ray diffraction measurements. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 152–163, 2010  相似文献   

11.
Summary A study was made of the reaction of phenylacetylene and diphenylacetylene with tetramethyl- and dimethyldiethyl dihydridedisiloxanes in the presence of H2PtCl6 as the catalyst. Some new five-membered organocyclosiloxanes were obtained and their structure was determined.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimisheskaya, No. 7, pp. 1267–1268, July, 1965  相似文献   

12.
Conclusions The heterofunctional condensation reaction gave for the first time organocyclosiloxanes with an endo-ethylene bridge between Si atoms; their structures were confirmed by29Si and13C NMR spectroscopy.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 657–662, March, 1988.  相似文献   

13.
新型含氟吡唑酰胺衍生物的合成   总被引:2,自引:1,他引:1  
以苯肼和乙酰乙酸乙酯为原料,设计并合成了8个未见报道的含氟吡唑甲酰胺衍生物,其结构经1H NMR, IR和元素分析表征.  相似文献   

14.
We explored phase separation and self‐assembly of perfluoroalkyl segments at the surface of polymer films obtained from latices of semifluorinated acrylate copolymers and the corresponding latex blends of nonfluorinated and semifluorinated polyacrylates. With laser‐induced secondary mass spectrometry the fluorine distribution was measured after annealing above the minimum film‐forming temperature of the polymers up to a depth of several micrometers. Depth profiles of a semifluorinated acrylate homopolymer and latex blends thereof with fluorine‐free alkylacrylates with 25, 50, and 75 mol % semifluorinated acrylate as well as a copolymer comprised of alkyl acrylate and semifluorinated acrylate (50/50 mol %) were investigated. In the case of latex blends containing both semifluorinated polyacrylates and fluorine‐free or low‐fluorine polymers, self‐assembly accounted for enrichment of the perfluoroalkyl segments at the surface. Coatings exhibiting low surface energy and having a substantially reduced total fluorine content were obtained. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 360–367, 2003  相似文献   

15.
从含氟取代基的芳醛从发,制备-系列贫电子烯烃(3);3与鉮盐反应,高立体选择性地合成了含氟贫电子环丙烷衍生物,其结构经1H NMR,13C NMR,IR,MS和元素分析表征,立体构型由二维NOE实验确定.  相似文献   

16.
A series of triblock semifluorinated n-alkanes of general formula F(CF2)n(CH2)m(CF2)nF (n = 6, 8 and m = 4, 6, 8) have been synthesized and characterized. The synthesis of triblock compounds was performed in two different ways according to the length of the hydrogenated moiety. Coupling of two molecules of β-(perfluoro-n-alkyl)ethyl iodides leads to the triblock materials F(CF2)6(CH2)4(CF2)6F and F(CF2)8(CH2)4(CF2)8F. The synthesis of compounds with larger hydrogenated part is accomplished in two steps by the addition of perfluoro-n-alkyl iodide F(CF2)nI to 1,5-hexadiene and 1,7-octadiene, respectively to give the diiodo-adducts which are subsequently deiodinated to the final triblock products F(CF2)6(CH2)6(CF2)6F, F(CF2)6(CH2)8(CF2)6F, F(CF2)8(CH2)6(CF2)8F and F(CF2)8(CH2)8(CF2)8F. The obtained triblock semifluorinated n-alkanes are characterized by low surface free energies with good lubricant properties usable as additives in ski-wax formulations.  相似文献   

17.
Chiral α-aminophosphonates were synthesized using (R) or (S)-1-phenylethylamine in the presence of BF3·Et2O under microwave irradiation in moderate to good yields. The new compounds were identified by ^1H NMR, ^19F NMR, IR and elemental analysis. Their antifungal activities were evaluated and some compounds were found to exhibit excellent antifungal activities. To the best of our knowledge, this is the first report on antifungal activity of chiral α-aminophosphonates containing fluorine moiety.  相似文献   

18.
A series of partially fluorinated ethers PFE-m,n with general formula F(CF2)mCH2CH2O(CH2)nH (m = 4, 6, 8 and n = 2, 3, 5, 8, 14, 18, 21) has been synthesized and characterized. The present work aimed to investigate the synthesis of PFE-m,n and evaluate some of their fundamental physico-chemical properties such as: specific gravity, refractive index, viscosity, solid-solid transitions, solubility and amphiphile surface activity in a variety of solvents. Further, a comparison between PFE-m,n and the well known semifluorinated n-alkanes F(CF2)m-(CH2)nH (FHm, n) with the same value of the m/n ratio have been reported.  相似文献   

19.
含氟侧基聚芳醚酮的合成与表征   总被引:15,自引:2,他引:13  
聚芳醚酮具有优异的化学、物理和机械性能 ,被广泛用于结构材料、高分子膜、航空航天和电子工业中所需的涂敷材料 [1,2 ] .传统的聚芳醚酮由于主链的规整性和刚性 ,使其难熔难溶 ,给加工和应用带来一定的困难 .许多研究者对其进行了大量的改性研究 [3,4 ] .氟元素具有较强的电负性 ,尺寸较小 ,可以形成强化学键和具有较好的电性能等 ,使其在化学物质的分子设计中成为极有价值的取代基 .含氟聚合物可以影响聚合物的溶解性、阻燃性、热稳定性、玻璃化转变温度、颜色、结晶性、介电常数和吸水性等性能 [5,6 ] .为了改善聚芳醚酮的溶解性、结晶…  相似文献   

20.
Europium and terbium salts of methacrylic acid (MA) and octanoic acid (OCA) were prepared by a method similar to that described in the literature. Either Eu(MA)3 or Tb(MA)3 with three double bonds (C?C) was used as a crosslinker containing rare earth metal ions, but the octanoic acid salts were used as additives. The salts were dissolved in methacrylic acid (<20%) and then copolymerized with methyl methacrylate (>80%) using AIBN (0.2 wt%) as initiator. The two types of polymers, one containing Eu(MA)3 or Tb(MA)3 and the other with Eu(OCA)3 or Tb(OCA)3, were synthesized by bulk copolymerization in molds made of two glass plates and characterized. The fluorescence spectroscopy of these polymers under ultraviolet/visible excitation light was investigated. The fluorescence excitation and emission spectra of the polymers showed the characteristic spectra of the free Eu3+ or Tb3+. The fluorescence intensity of the rare earth metal ions increased with increasing rare earth metal content. Fluorescence measurements for Eu(MA)3, Tb(MA)3, and Eu(OCA)3 polymers do not display fluorescence quenching behavior within the range of the rare earth metal content used in our experiments. But for Tb(OCA)3 polymers, this phenomenon was observed, illustrating that ionic aggregates exist in Tb(OCA)3 polymeric systems.  相似文献   

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