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  • 1
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 188 (1987), S. 2141-2150 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Fumaric esters of poly(ethylene glycol) (1a-d) were prepared as macromonomers. The halfesters 1a and 1c were obtained by interaction of maleic anhydride with the monoethers of poly(ethylene glycol) (2a and 2b) in the presence of 4-dimethylaminopyridine, and the diesters 1b and 1d by esterification of methyl hydrogen fumarate (13) with the monoethers of poly(ethylene glycol) (2a and 2b). The macromonomers were found to homopolymerize and to copolymerize with styrene and methyl methacrylate following a radical polymerization mechanism.
    Additional Material: 2 Ill.
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  • 2
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 115 (1968), S. 56-63 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Um Copolymere des Trioxans mit Acenaphthylen zu erhalten wurde ein Gemisch beider Monomerer in Benzol oder Tetrachlormethan sowie in Schmelze mittels Bortrifluoriddiäthylätherat polymerisiert. Bei den meisten Monomerenverhältnissen wurden unabhängig vom Umsatz Produkte erhalten, die aus zwei Fraktionen bestehen. Die eine Fraktion ist schmelzbar, in Benzol löslich und enthält fast nur Polyacenaphthylen, die andere unschmelzbar, unlöslich in organischen Lösungsmitteln und mit hohem Polyformaldehydgehalt. Bei der Polymerisation eines Gemisches aus beiden Monomeren unter der Wirkung von γ-Strahlen wurden nur unlösliche Produkte erhalten. Auf Grund der Versuchsergebnisse und der Literaturangaben wurde die Bildung der unlöslichen Produkte zu erklären versucht. Nach Ansicht der Autoren dürfte unter den gegebenen experimentellen Bedingungen kaum eine Copolymerisation der beiden Monomeren stattfinden.
    Notes: With the aim of preparing copolymers of trioxane with acenaphthylene, the polymerization of a mixture of both monomers was carried out in the presence of boron trifluoridediethyl etherate in benzene and tetrachloromethane and in melt. In most monomer ratios, irrespective of the degree of conversion, products were obtained, which were composed of two fractions: one fusible and soluble in benzene and tetrachloromethane, containing almost pure polyacenaphthylene, and another infusible and insoluble in organic solvents with a high polyformaldehyde content. On polymerization of the monomer mixture under the action of γ-rays only insoluble and infusible products were formed. On the basis of the experimental results and the literature data an attempt is made to explain the formation of insoluble products and an opinion is expressed, that no copolymerization of the monomers is likely to take place under the experimental conditions employed.
    Additional Material: 5 Ill.
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  • 3
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Es wurde der Einfluß von Elektronacceptoren auf das Dissoziationsgleichgewicht im System BF3·Et2O/π-Elektronenacceptor in Dichloräthan konduktometrisch untersucht. Als Acceptoren dienten Tetracyanäthylen (TCNE) und 1.3.5-Trinitrobenzol (TNB) in mit dem Katalysator vergleichbaren Mengen. In Lösungen mit niedriger Dielektrizitätskonstante verhält sich BF3·Et2O wie ein schwach dissoziierter Elektrolyt. Der Wert der Dissoziationskonstante ist 1,64·10-9. Die Anwesenheit von Elektronenacceptoren erhöhte die Äquivalenzleitfähigkeit des Systems. Beide Dissoziationskonstanten betragen in Anwesenheit von TNB und TCNE 2,88·10-9 bzw. 3,25·10-9.Die Funktion log λ = f(log c) ist in allen drei Systemen linear. Sie besteht jedoch aus zwei geraden Teilen mit verschiedenen Steigungen, was auf eine Veränderung der elektrochemischen Eigenschaften der Systeme hinweist. Bei Konzentrationserhöhung vermindert sich die Leitfähigkeit langsamer, was wahrscheinlich auf die Bildung von Ionenassoziaten zurückzuführen ist.
    Notes: The effect of strong π-electron acceptors on the ion equilibrium in the system boron fluoride-diethyl etherate (BFE)/ethylene dichloride was investigated by means of conductivity measurements. The acceptors used were tetracyanoethylene (TCNE) and 1.3.5-trinitrobenzene (TNB) in amounts commensurate with the catalyst concentration. In the solvent used BFE behaves as a weakly dissociated electrolyte with a dissociation constant of about 1.64·10-9 mole/l. The electron acceptors presented increase the equivalent conductance of the system. The dissociation constants in the presence of TNB and TCNE are 2.88·10-9 and 3.25·10-9 mole/l., respectively. Plots of log λ vs. log c for each of the systems show two straight parts with different slopes, which indicates a change in the electrolyte behaviour. This relative increase in conductivity with increasing concentration can be due to association between ion pairs and free ions.
    Additional Material: 2 Ill.
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  • 4
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Die durch Anionen-Radikale wie Kaliumdiphenylketyl oder Kaliumdihydronaphthylid und die Kalium-Graphit-Einschlußverbindungen C8K, C16K, C24K, und C32K initiierte Polymerisation von Methacrylaldehyd (Methacrolein, MAC) und Crotonaldehyd (CA) wurde untersucht, um Polymerisationsbedingungen aufzufinden, unter denen Nebenreaktionen mit Aldehydgruppen im Polymeren in möglichst geringem Umfang stattfinden. Die Struktur der Polymeren wurde durch IR- und NMR-Spektroskopie bestimmt. Es wurde gefunden, daß Polymethacrylaldehyd (PMAC) einen hohen Gehalt an Tetrahydropyranringen hat. Mit Hilfe quantenchemischer Methoden wurde gezeigt, daß die Bildung von Komplexen aus dem wachsenden Kettenende und dem Monomeren energetisch bevorzugt ist und zur Bildung von Tetrahydropyranringen während der Wachstumsreaktion von MAC führt.
    Notes: The polymerization of methacrylaldehyde (methacrolein; MAC) and crotonaldehyde (CA) initiated by the anion-radical type initiators potassium diphenylketyl, potassium dihydronaphthylide and the potassium-graphite inclusion compounds C8K, C16K, C24, and C32K was investigated with the intention to find polymerization conditions under which side reactions with aldehyde groups in the polymer do not proceed to a considerable degree. The structures of polymethacrylaldehyde (PMAC) and polycrotonaldehyde were determined by IR and NMR spectroscopy. It was established that PMAC has a high content of tetrahydropyran rings. With the aid of quantum chemical methods it was shown that the formation of complexes between the propagating polymer end and the monomer molecule is energetically advantageous and leads to the formation of tetrahydropyran rings in the propagation reaction of MAC.
    Additional Material: 4 Ill.
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  • 5
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 175 (1974), S. 3305-3307 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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  • 6
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 7
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 181 (1980), S. 671-675 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The photolysis of triphenylmethyl salts with anions such as SbCl-6, FeCl-4 and AsF-6 was investigated in inert and oxygen atmosphere. On irradiation by visible light the characteristic bands of the cation disappeared in 20 min and in 15 h at concentrations of 10-4 M and 10-3 M, respectively. The main photolytes identified were triphenylmethane, triphenylchloromethane, triphenylcarbinol, benzophenone, fluorenone, fluorene, 9-hydroxy-9-phenylfluorene, 9-phenylfluorene besides 2-3% nonidentified products. The results showed that the product composition of the photolyzed mixture depended only slightly on the atmosphere used, the differences in the amounts of the products being more significant.
    Additional Material: 2 Ill.
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  • 9
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The nature of alkali derivatives of acetone (ADA) and active centres (AC) in the anionic polymerization of isopropenyl methyl ket one (IMK) was studied by means of IR spectroscopy. Solutions of ADA and of the AC of IMK in tetrahydrofuran show a characteristic absorption at 1560 - 1610 cm-1, due to the stretching vibrations of the delocalized isopropenyl oxide group. Two kinds of equimolar complexes are formed between acetone and ADA, depending on the nature of the counterion (Li+, Na+, K+, Cs+). The same interaction is observed between the AC of oligo (IMK) and the carbonyl group of the last but one monomeric unit (penultimate effect).
    Additional Material: 10 Ill.
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  • 10
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Amphiphilic block macromonomers possessing a central unsaturation were synthesized by condensation of polystyrene half-ester of maleic acid {α-[2-(3-carboxyacryloyloxy)ethyl]-ω-sec-butylpoly[1-phenylethylene]} with poly(ethylene glycol) monoether or polystyrene-block-poly(ethylene oxide). In the radical monomer cis-trans-isomerization homopolymerization of the diblock macromonomers, four-to eight-armed amphiphilic star-shaped copolymers were obtained. Radical copolymerization of the diblock macromonomers with styrene led to graft copolymers with low degree of grafting. The triblock macromonomers proved to be unable to polymerize.
    Additional Material: 2 Ill.
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