- Synthesis and characterization of a novel fluorinated polyether glycol with fluorinated side chains via "living/controlled" cationic polymerization
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A novel fluorinated polyether glycol with fluorinated side chains is synthesized via "living/controlled" cationic ring-opening polymerization of tetrahydrofuran and fluorine-containing epoxy compounds (FO). The effects of polymerization conditions on monomer conversion, number-average molecular weight (Mn), molecular weight distribution (Mw/Mn) are measured. Our investigations have shown that the use of a mixed solvent (dichloromethane/1,4-dioxane) can prevent intra- and intermolecular transfer reactions, due to more nucleophilic oxygen atom in 1,4-dioxane. Using BF3·CH3OH/CH2OHCH2OH as initiation system, polymers with predictable number-average molecular weight, narrow molecular weight distribution (1.03 w/Mn 1.08) were produced. On the basis of the reactivity ratio of FO/THF and monomer conversion, a mechanism of living/controlled polymerization has been proposed.
- Li, Lingling,Li, Ying,Wang, Xia,Qi, Yuanchun,Hu, Jiaojiao,Fang, Zhou,Dong, Qingzhi
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- The surface properties and corrosion resistance of fluorinated polyurethane coatings
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Fluorine-containing epoxy (FO) compounds were synthesized through a one-step process from 2,2,3,3-tetrafluoro-1-propanol (TFP) and epichlorohydrin (ECH). Cationic polymerization was adopted to prepare fluorinated polyglycol with controllable molecular weight. The structure of FO and FPO were studied by FTIR, NMR and GPC and a two-component fluorinated polyurethane coating was synthesized using FPO and methyl diphenylenediisocyanate (MDI) with a room temperature curing method. We characterized the contact angle of the surface of the coating. The water resistance and resistance to salt spray as well as SEM imaging of the film surface indicates that hydrophobicity, water resistance, and corrosion resistance are improved due to surface migration of the fluorine element.
- Wang, Xia,Hu, Jiaojiao,Li, Ying,Zhang, Jinrui,Ding, Yuanyuan
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- The synthesis and curing kinetics study of a new fluorinated polyurethane with fluorinated side chains attached to soft blocks
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Fluorinated polyurethane (FPU) with fluorine in the side chain was obtained using fluorinated polyether glycol (FPO) with fluorinated side chains and 4,4′-diphenyl methane diisocyanate (MDI). The direct visual inspection of microstructures by SEM revealed that the separation degree of soft and hard segments decreased with the introduction of fluorinated groups into polyurethane soft segments, leading to a decrease in the crystallinity of FPU. The glass transition temperatures (Tg) measured by DMA indicated that the optimal working temperature window of FPU separating soft and hard glass transitions became narrow. And the mechanical properties and surface properties of the FPU were also measured. Curing kinetics of FPU was studied using a rotational rheometer, and the activation energy of FPU was obtained. The relationship between the curing temperature and the mobility of fluorinated groups was characterized by XPS. The result showed that F content in the FPU surface decreased with increasing curing temperature.
- Li, Lingling,Wang, Xia,Li, Zan,Bi, Wei,Li, Ying,Qi, Yuanchun,Dong, Qingzhi
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- Synthesis and properties of fluorinated thermoplastic polyurethane elastomer
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A series of fluorinated thermoplastic polyurethane elastomers (FTPU) based on self-synthesized fluorinate polyether diol (PFGE) were prepared by two-step polymerization. For the purpose of improving the molecular weight and mechanical property of FTPU, polybutylene adipate (PBA) was used to be compounded with PFGE as the soft-segment of FTPU. Effects of the mass ratio of PFGE/PBA and the mass fraction of hard-segment on the mechanical property of FTPU were investigated. The structure and morphology of FTPU were characterized by FTIR, GPC, DMA, surface tension and AFM analysis.
- Liu, Tao,Ye, Lin
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- Rational design 2-hydroxypropylphosphonium salts as cancer cell mitochondria-targeted vectors: Synthesis, structure, and biological properties
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It has been shown for a wide range of epoxy compounds that their interaction with triphenylphosphonium triflate occurs with a high chemoselectivity and leads to the formation of (2-hydroxypropyl)triphenylphosphonium triflates 3 substituted in the 3-position with an alkoxy, alkylcarboxyl group, or halogen, which were isolated in a high yield. Using the methodology for the disclosure of epichlorohydrin with alcohols in the presence of boron trifluoride ether-ate, followed by the substitution of iodine for chlorine and treatment with triphenylphosphine, 2-hydroxypropyltriphenylphosphonium iodides 4 were also obtained. The molecular and supramolec-ular structure of the obtained phosphonium salts was established, and their high antitumor activity was revealed in relation to duodenal adenocarcinoma. The formation of liposomal systems based on phosphonium salt 3 and L-α-phosphatidylcholine (PC) was employed for improving the bioavailabil-ity and reducing the toxicity. They were produced by the thin film rehydration method and exhibited cytotoxic properties. This rational design of phosphonium salts 3 and 4 has promising potential of new vectors for targeted delivery into mitochondria of tumor cells.
- Amerhanova, Syumbelya K.,Dimukhametov, Mudaris N.,Gubaidullin, Aidar T.,Islamov, Daut R.,Litvinov, Igor A.,Lyubina, Anna P.,Mironov, Vladimir F.,Nemtarev, Andrey V.,Pashirova, Tatiana N.,Titov, Eugenii A.,Tsepaeva, Olga V.,Voloshina, Alexandra D.
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- Thermal desulfurization of (Alkoxymethyl)thiiranes
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Reaction of (alkoxymethyl)oxiranes with thiourea in methanol has afforded the corresponding thiiranes, and catalyst-free thermal desulfurization of the products has been studied. The major products of desulfurization are alcohols and alkenes, both in the cases of (polyfluoroalkyloxymethyl)thiiranes and their non-fluorinated analogs. Longer alkyl chain in thiiranes favors formation of alcohols over alkenes formation in the course of desulfurization.
- Nalet'Ko,Pervova,Gorbunova,Zapevalov, A. Ya,Toporova,Saloutin
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p. 2120 - 2124
(2015/02/02)
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- [(Polyfluoroalkoxy)methyl]thiiranes and 2-anilinoethanethiols
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By reaction of appropriate oxiranes with thiourea [(polyfluoroalkoxy) methyl]-substituted thiiranes were obtained that are key compounds for the synthesis of perfluoro-containing 1,2-aminopropanethiols.
- Guseinova,Magerramov,Allakhverdiev
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experimental part
p. 946 - 949
(2009/06/18)
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- Promising prospects for using partially fluorinated alcohols as O-nucleophilic reagents in organofluoric synthesis
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Perfluoroolefins react with isopropyl alcohol under the conditions of radical initiation to form partially fluorinated aliphatic alcohols. The reactions of these alcohols with hexafluoropropylene and compounds containing labile halogen atoms (in particular, with allyl bromide and epichlorohydrin) were studied.
- Il'in,Il'in,Bakhmutov,Furin,Pokrovskii
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p. 405 - 418
(2008/02/02)
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- FLUORINE-CONTAINING 2,3-EPOXYPROPYL ETHERS. SYNTHESIS AND SPECTRAL CHARACTERISTICS
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Polyfluoroalkyl 2,3-epoxypropyl ethers were prepared by the reactions of fluoro olefins with 2,3-epoxy-1-propanol in presence of potassium fluoride and under the conditions of phase-transfer catalysis. 1H and 19F NMR- and mass-spectral characteristics of the polyfluoroalkyl ethers were determined.
- Solov'ev, D. V.,Kolomenskaya, L. V.,Rodin, A. A.,Zenkevich, I. G.,Lavrent'ev, A. N.
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p. 611 - 615
(2007/10/02)
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