Search results for "Cyanate"
showing 10 items of 210 documents
On the use of Persian gum for the development of antiviral edible coatings against murine norovirus of interest in blueberries.
2021
In the last decades, berries have been identified as important vehicles for the transmission of foodborne viruses and different strategies are being explored to eliminate or reduce viral contamination in these fruits. The aim of this work was to develop novel edible coatings with antiviral properties for inactivating and reducing murine norovirus (MNV). Firstly, the effect of gelatin (G) addition on Persian gum (PG) films was studied in terms of microstructural, mechanical, optical, and water barrier properties. The following PG:G ratios were considered: 100:0, 75:25, 50:50, 25:75, and 0:100. Microstructure analysis revealed the compatibility of both hydrocolloids since no phase separation …
Synthesis, Crystal Structure and Magneto‐Structural Correlation of an Unusual Thiocyanato‐Bridged Nickel( II ) Compound, [Ni(μ‐NCS)(dpt)(NCS)] 2 [Ni(…
2003
Reaction of Ni(ClO4)2·6H2O with bis(3-aminopropyl)amine (dpt) and ammonium thiocyanate produces the novel thiocyanato-bridged nickel(II) compound [Ni(μ-NCS)(dpt)(NCS)]2[Ni(μ-NCS)(dpt)(NCS)]4, which has been structurally characterised. The structure determination reveals that there are two different molecules in the crystal lattice; one is dinuclear and other is tetranuclear. Low-temperature magnetic measurements show that there are ferro- as well as antiferromagnetic interactions. The ferromagnetic interaction arises from the dinuclear part and the doubly bridged part of the tetranuclear unit; the antiferromagnetic interaction occurs between singly bridged nickel centres in the tetranuclear…
Cure kinetics of a cobalt catalysed dicyanate ester monomer in air and argon atmospheres from DSC data
2004
A kinetic analysis of the cyclotrimerisation reaction of a dicyanate ester monomer catalysed by cobalt(II) acetylacetonate and nonylphenol in air and argon atmospheres has been carried out by differential scanning calorimetry (DSC). Dynamic and isothermal DSC scans as well as the glass transition temperature are the experimental data obtained. From isothermal scans a higher cyanate conversion in air than in argon was obtained. The cyanate conversions are satisfactorily described with a second-order kinetic equation in the kinetically controlled region, and by m-order (m<1) equation after vitrification is reached. Activation energies determined by different procedures agree among them, showi…
Thioether-Bearing Hyperbranched Polyether Polyols with Methionine-Like Side-Chains: A Versatile Platform for Orthogonal Functionalization
2016
The synthesis of thioether-bearing hyperbranched polyether polyols based on an AB/AB2 type copolymerization (cyclic latent monomers) is introduced. The polymers are prepared by anionic ring-opening multibranching copolymerization of glycidol and 2-(methylthio)ethyl glycidyl ether (MTEGE), which is conveniently accessible in a single etherification step. Slow monomer addition provides control over molecular weights. Moderate dispersities (Đ = 1.48–1.85) are obtained, given the hyperbranched structure. In situ 1H NMR copolymerization kinetics reveal reactivity ratios of rG = 3.7 and rMTEGE = 0.27. Using slow monomer addition, copolymer composition can be systematically varied, allowing for th…
Lineare polyester mit carboxylendgruppen und deren bestimmung
1955
Durch Umsetzung von „alkoholischen” Bernsteinsaure-1,6-Hexandiol-Polyestern mit Bernsteinsaureanhydrid in Benzol werden kettenanaloge Polyester mit endstandigen Carboxylgruppen hergestellt. Die Titration dieser Carboxylgruppen ergibt Molgewichte bis ∼ 7 · 103. Mit Phenylisocyanat in indifferenten Losungsmitteln reagieren Polyesterdicarbonsauren unter Kettenverlangerung und Bildung von kettenstandigen Carbonsaureanhydridgruppen. Die Umsetzung der Polyester-dicarbonsauren in Phenylisocyanat ohne Verdunnungsmittel erfolgt kettenanalog unter Bildung von Carboxanilidendgruppen. Durch photometrische Anilinbestimmung nach der Hydrolyse konnen diese Endgruppen quantitativ bestimmt und Molgewichte b…
Crystal structure, spectroscopic characterization and Hirshfeld surface analysis of trans-diaqua[2,5-bis(pyridin-4-yl)-1,3,4-oxadiazole]dithioc…
2019
The NiII atom in the mononuclear title complex has an almost regular octahedral N4O2 coordination geometry. In the crystal, the complex molecules are linked in a three-dimensional network through strong O—H⋯N hydrogen bonds.
Synthesis, structure, physicochemical characterization and theoretical evaluation of non-covalent interaction energy of a polymeric copper(II)-hydraz…
2019
Abstract One dimensional polymeric copper-hydrazone complex {[Cu(H0.5L)(µ1,3-SCN)]0.5ClO4·0.5MeOH}n (1) has been synthesized with Cu(ClO4)2·xH2O and N'-(1-(pyridin-2-yl)ethylidene)acetohydrazide (HL) in presence of NaSCN. The ligand and the complex have been characterized by several spectroscopic techniques (IR, UV–Vis and EPR), cyclic voltammetry and the structure of 1 has been determined by single crystal X-ray diffraction. The complex is an infinite one dimensional polymer bridged by thiocyanate. The magneto-structural correlation has been determined and the non-covalent interactions present in the molecule have been energetically evaluated by means of DFT calculations.
Controlled Synthesis of Multi-Arm Star Polyether-Polycarbonate Polyols Based on Propylene Oxide and CO2
2013
Multi-arm star copolymers based on a hyperbranched poly(propylene oxide) polyether-polyol (hbPPO) as a core and poly(propylene carbonate) (PPC) arms are synthesized in two steps from propylene oxide (PO), a small amount of glycidol and CO2 . The PPC arms are prepared via carbon dioxide (CO2 )/PO copolymerization, using hbPPO as a multifunctional macroinitiator and the (R,R)-(salcy)CoOBzF5 catalyst. Star copolymers with 14 and 28 PPC arms, respectively, and controlled molecular weights in the range of 2700-8800 g mol(-1) are prepared (Mw /Mn = 1.23-1.61). Thermal analysis reveals lowered glass transition temperatures in the range of -8 to 10 °C for the PPC star polymers compared with linear …
Synthese von 2-Acyloxy- und 2-Alkyloxy-3-ketoglycalen und ihren Bromaddukten
1983
Die an den Hydroxygruppen acetyl-, pivaloyl- und methylgeschutzten 2-Hydroxy-3-ketoglycale 5a, 5b bzw. 11 werden durch Oxidation der entsprechenden 1-O-Acylglucopyranosen 3a, 3b bzw. 9 an der freien 3-Hydroxygruppe mit Dimethylsulfoxid/Acetanhydrid oder Chlorsulfonylisocyanat hergestellt und charakterisiert. Nur beim Acetylderivat 3a verlaufen die Oxidation und die Eliminierung des 1-Acetyloxysubstituenten in einem Schritt. Beim Pivaloylderivat 3b und beim Methylderivat 9 mus die Eliminierung aus der 3-Ulose 4 bzw. 10 mit Diazabicycloundecen (DBU) vervollstandigt werden. – Die geschutzten Hex-1-enopyran-3-ulosen 5a, 5b und 11 addieren Brom stereoselektiv unter Bildung der D-ribo-konfigurier…
Thermophysical Properties of Mixtures of 1-Ethyl-3-methylimidazolium Methylsulfate or 1-Ethyl-3-methylimidazolium Thiocyanate with Alcohols
2021
In the present paper, densities, speeds of sound, and viscosities of four binary mixtures containing the ionic liquids 1-ethyl-3-methylimidazolium methylsulfate and 1-ethyl-3-methylimidazolium thio...