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  • 1
    Electronic Resource
    Electronic Resource
    Water-soluble copolymers. VI. Dilute solution viscosity studies of random copolymers of acrylamide with sulfonated comonomers (1984)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 29 (1984), S. 713-730 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Dilute solution viscosity of a series of random copolymers of acrylamide (AM) with sodium-2-acrylamido-2-methylpropane sulfonate (NaAMPS) and with sodium-2-sulfoethylmethacrylate (NaSEM) has been studied using a four-bulb shear dilution capillary viscometer. The hydrodynamic volume of the copolymers in aqueous media was determined as a function of salt concentration, temperature, shear rate, and time. A linear relationship was observed between the intrinsic viscosity [η]0 and the reciprocal of the square root of ionic strength in sodium chloride solutions, with salt concentrations varying from 0.043M to 0.257M. Negative temperature coefficients for [η]0 indicate a decrease in the hydrodynamic volume of the ionic polymer molecules with increasing temperature. The relative zero-shear-intrinsic-viscosity change in distilled water to 0.257M sodium chloride aqueous media is used to elucidate viscosity-structure relationships. A maximum value is reached for this parameter at a composition of about 30 mol % of ionic comonomers for AM-NaAMPS and AM-NaSEM copolymer series.
    Additional Material: 14 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1984.070290301
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  • 2
    Electronic Resource
    Electronic Resource
    Über den einfluß ungesättigter verbindungen auf die polymerisation des trioxansHerrn Prof. Dr. K. HAMANN zum 60. Geburtstag gewidmet (1966)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 99 (1966), S. 35-48 
    Details
    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: The Polymerization of trioxan in the presence of small amounts of unsaturated compounds acting as chain transfer agents is described, The resulting polymers contain a larger alkali and temperature stable fraction. The chain transfer action of the unsaturated compounds can be explained by addition of the Polyoxymethlene cation to the carbon double bond followed by cleavage of a proton. Copolymerization may also occur to a smaller extent, this explains the increasing amounts of stable polymer.Most of the unsatitrated compounds investigated lower the conversion of the trioxan polymerization. The reason for this is an inhibiting interaction the between the catalyst and the unsaturatedc compound.
    Notes: Die Polymerisation des Trioxans in Gegenwart kleiner Mengen an ungesättigten Verbindungen als Kettenüberträer wird beschrieben. Sie führ zu Polymerisaten mit einein erhöhten alkali-und temperaturbeständigen Antell. Die Kettenübertragung kann durch eine Anlagerung des Polyoxymethylen-Kations an die Kohlenstoff-Doppelbindung und anschlißende Abspaltung eines Protons erklärt werden. Daneben erfolgt in geringern Umfang, eine Copolymerisation, welche die Zunahme des stabilen Polymeranteils bewirkt.Die meisten der untersuchten ungesättigten Verbindungen erniedrigen den Umsatz bei der Trioxanpolymerisation. Als Ursache dafür ist eine aktivitAtshemmende Weebselwirkung zwischen Katalysator und ungesättigter Verbindung anzusehen.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1966.020990104
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  • 3
    Electronic Resource
    Electronic Resource
    Die copolymerisation des trioxans mit substituierten 1.3-dioxacycloalkanenVorgetragen von K. WEISSERMEL auf dem IUPAC-Symposium fü Makromolekulare Chemie am 4. 10. 1966 in Kyoto. (1967)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 107 (1967), S. 149-157 
    Details
    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: 2-Substituted 1.3-dioxacycloalkanes wbich are easily available from diols and aldehydes or ketones show an unusual behaviour in the copolymerization with trioxane. At first, ring scission of trioxane leads to the formation of formaldehyde which subsequently reacts during the induction period with the substituted dioxacycloalkane forming the cyclic formal and liberating the carbonyl-component. Only after this re-acetalization is nearly finished, the ceiling-concentration of monomeric formaldehyde is attained which allows the copolymerization of trioxane and the unsubstituted 1.3-dioxacycloalkane to proceed.
    Notes: In 2-Stellung substituierte 1.3-Dioxacycloalkane sind aus zweiwertigen Alkoholen und Aldehyden oder Ketonen leicht zugänglich. Sie zeigen bei der Copolymerisation mit Trioxan ein ungewöhnliches Verhalten. Es wird zunächst aus Trioxan unter Ringöffnung Formaldehyd abgespalten, der in einer Induktionsperiode mit dem substituierten Dioxacryloalkan unter Bildung von cyclischen Formalen und Freisetzung der Carbonylkomponente reagiert. Erst wenn these Umacetalisierung weitgehend beendet ist, kann sich monomerer Formaldehyd im Reaktionsgemisch bis zur ceiling-Konzentration anreichern, so daß schließlich eine Copolymerisation von Trioxan mit unsubstituiertem 1.3-Dioxacycloalkan ausgelöst wird.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1967.021070115
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  • 4
    Electronic Resource
    Electronic Resource
    Isolierung und charakterisierung von cyclischen oligomeren des formaldehydsVorgetragen von K. H. BURG auf dem Makromolekularen Kolloquium in Freiburg am 10. März 1967. (1968)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 111 (1968), S. 181-193 
    Details
    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: Residues from the polymerization of trioxane were analysed. Besides trioxane and tetroxane higher cyclic oligomers of formaldehyde could be isolated. The cyclic pentamer was obtained using preparative gaschromatography. The zone melting technique was suitable to isolate a ring containing 15 formaldehyde units.The acid-catalyzed pyrolysis of polytrioxane also leads to higher oligomers of formaldehyde. Gaschromatographic investigations indicate the formation of pentoxane, and Probably also of hexoxane.The cyclic acetals are characterized on the basis of their IR, NMR, and mass spectra.
    Notes: Bei der Aufarbeitung von Rückständen aus der Polymerisation von Trioxan konnten neben Trioxan und Tetroxan auch höhere cyclische Oligomere des Formaldehyds isoliert werden. Das Pentamere wurde dabei mit Hilfe der präparativen Gaschromatographie gewonnen, während zur Isolierung eines Ringes mit 15 Formaldehydeinheiten die Methode des Zonenschmelzens geeignet war. Die durch saure Agentien katalysierte Pyrolyse von Polytrioxan führt ebenfalls zu höheren cyclischen Oligomeren des Formaldehyds. Durch pyrolse-gaschromatographische Untersuchungen wurde die Bildung von Pentoxan sichergestellt und das Entstehen von Hexoxan wahrscheinlich gemacht. Zur Charakterisierung der isolierten ringfömigen Acetale wurden ihre Polymerisierbarkeit, ihre Schmelzpunkte und ihre IR-, Kernresonanz- und Massenspektren herangezogen.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1968.021110117
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  • 5
    Electronic Resource
    Electronic Resource
    Copolymerization of trioxane by γ-radiation (1967)
    New York : Wiley-Blackwell
    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 183-192 
    Details
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: High molecular copolymers of trioxane with different cyclic ethers and formals were produced by γ-radiation from a 60Co source. It was polymerized in the solid state at 53°C. Polymerization does not occur in the melt. Irradiation was carried out with exclusion of air at a dose rate of 7 × 103 rad/hr. The polymerization rate was increased very considerably in the presence of 1,3-dioxolane and epichlorhydrin; the addition of other comonomers may reduce the yield. The concentration of the comonomer is generally higher in the polymer than in the initial mix. These comonomers which increase the polymerization rate are introduced preferentially into the polymer chain; this is proved by the unstable polymer part and the thermal stability. Experiments with the trioxane-1,3-dioxolane system revealed that the unstable polymer part is markedly reduced and the heat stability considerably inproved with rising concentrations of this monomer. The thermal stability and the reduced viscosity of these copolymers are within the range of technical processability.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1967.150050117
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