Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Stat-poly(Ethylene oxide-co-propylene oxide). Synthesis, NMR characterization and crystallinity studies. Correlation with monte carlo simulation (1996)
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 237 (1996), S. 55-77 
    Details
    ISSN: 0003-3146
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Durch anionische Polymerisation nach einem bereits beschriebenen neuartigen heterogen-katalysierten Prozeß wurden statistische Poly(ethylenoxid-co-propylen-oxid)-Copolymere mit niedrigen Molekulargewichten hergestellt. Die Copolymeren wurden mit 1H NMR-und 13C NMR-Spektroskopie charakterisiert, um zum einen die Verteilung der um eine Ethylenoxid-Gruppe gebildeten Triaden und zum anderen die durchschnittliche Länge der Poly(ethylenoxid)-Sequenzen zu bestimmen. DSC-Messungen ergaben niedrige Kristallisationsgrade. Die so erhaltenen Copolymeren wurden erfolgreich als polymere Feststoffelektrolyte eingesetzt und zeigen bei Raumtemperatur hohe Leitfähigkeitswerte. Die Ergebnisse stimmen gut mit den Resultaten einer unter Verwendung des für die radikalische Polymerisation entwickelten Copolymerisations-Terminal-Modells durchgeführten Monte Carlo-Simulation überein.
    Notes: Low-molecular-weight stat-poly(ethylene oxide-co-propylene oxide) polymers have been prepared anionically using a new heterogeneous catalytic process previously reported. They were fully characterized by 1H and 13C NMR spectroscopy in order to determine the distribution of the ethylene oxide (EO)-centered triads, as well as the average lengths of poly(ethylene oxide) (PEO) sequences. Low degrees of crystallization were determined by DSC. These copolymers have been successfully used for applications in the solid polymer electrolytes field and high levels of conductivity at room temperature have been measured. The results are in good agreement with those obtained from a Monte Carlo simulation method using the copolymerization terminal model developed for radical polymerization.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/apmc.1996.052370103
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Catalyseurs Ziegler-Natta supportés sur MgCl2 pour la polymérisation du propène. I. Etude de la réaction entre le triéthylaluminium et le benzoate d'ethyle (1984)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2611-2624 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In this article we describe a study of the reaction between triethylaluminium (TEA) and ethylbenzoate (BE) in a heptane solution by Fourier transform, infrared (IR), and ultraviolet (UV) spectroscopy. These compounds were chosen as a model of the cocatalytic solution used with a Ziegler-Natta catalyst supported on MgCl2 for the stereospecific polymerization of propene. In the polymerization concentration range a 2 TEA:1 BE yellow complex was added to the solution and no free BE could be detected at a AI/BE molar ratio above 2: the solution contained only free and complexed TEA. The complex decomposed spontaneously to a colorless aluminium alcoholate. The rate of decomposition remained slow at room temperature and the reaction was enhanced by heating or by a high AI/BE ratio or high AI concentration. The decomposition was inhibited in the presence of an olefin.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1984.170221027
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Anomalies in the rheological behavior of polyethylene with very broad molecular weight distribution (1987)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 34 (1987), S. 1335-1343 
    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: The rheological behavior of high density polyethylenes with very broad molecular weight distribution is studied in the molten state starting from freshly synthesized powders. The complex viscosity increases slowly up to a limiting value as a function of ageing of the polymer and faster when the molten polymer is stirred. The phenomena are explained by an heterogeneous distribution of very high molecular weight nodules in the polymer arising from the synthesis and is proved by the preparation and characterization of polymers presenting the opposite heterogeneity and behavior (very low molecular weight nodules).
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1987.070340401
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Superantiferromagnétisme des catalyseurs de polymérisation à base de Ticl3 (1972)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 157 (1972), S. 307-310 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1972.021570131
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Preparation of bisupported catalysts for ethylene polymerization (1990)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 191 (1990), S. 3087-3096 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: SiO2-MgCl2 supports were prepared thermally at moderate temperature. The preparation was improved by the use of an additive stabilizing MgCl2-ammonium chloride. The best supports contain less than 5 wt.-% Mg with about 2/3 of Mg as MgCl2 and keep most of the porous properties of the starting silica. Bisupported catalysts obtained after TiCl4 impregnation (2-4 wt.-% Ti) present high activities and productivities in gas-phase ethylene polymerization and copolymerization.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1990.021911227
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Molecular weight control of linear polyethylenes prepared in gas phase with Ziegler catalysts (1991)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 192 (1991), S. 1509-1515 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Linear polyethylenes covering the range from high to low density were prepared in gas phase using an MgCl2-supported Ziegler catalyst deposited on silica (bisupported catalyst). The comonomer used was 1-butene. Molecular weights are dependent both on 1-butene concentration and hydrogen pressure. The interaction of these two factors can be interpreted by the enhancement of the transfer reactions after 1-butene insertion.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1991.021920705
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Irreversible activation effects in ethylene polymerization (1993)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 194 (1993), S. 451-461 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Activation and deactivation phenomena commonly observed in the case of slurry or gas phase ethylene polymerization kinetics are associated to molecular aspects of the formation and inhibition of active centers. As a preliminary study of the problem, we have to identify what step during the formation or action of the active centers is concerned by the well-known activating agents: temperature, ethylene pressure and α-olefins addition. They all lead to an irreversible increase in the polymerization rate, which can be attributed to the creation of new active centers. Hydrogen was also considered, since it is an activator for propene polymerization, but it deactivates ethylene polymerization. This deactivation is often partially reversible. Different explanations of this complex behaviour are presented.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1993.021940208
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Caractérisation texturale de résines en milieu réactionnel (1981)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 182 (1981), S. 873-882 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Thermoporometry, a method based on the microcalorimetric analysis of liquid-solid state transformation inside porous substances, gives access to porous volume versus pore size distribution. For the first time, this method is applied to the analysis of flexible products swellable in the reference medium. Conditions for applying transposition thermoporometry to this new class of porous substances are discussed. An example is given, which leads to suggest a model for the swelling process of a macroporous resin. Generalization of this method would induce a major progress in the study of swollen systems and enable better understanding of their structures.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1981.021820319
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Caractérisation texturale par thermoporométrie, à l'état gonflé par l'eau, de résines échangeuses d'anions (1984)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 185 (1984), S. 1105-1116 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Thermoporometry is used to determine the size and the volume of the cavities of anion exchange resins swollen in water. The conditions of the application of thermoporometry are different of those met with non-functionalised resins. An important fraction of the water remains bond to the polymer and does not change its state when cooling. Nevertheless, it is possible to deduce from the freezing of the non-bound water the geometrical characteristics of the cavities of the resin which determine the fluid inside circulation. In most cases it is possible to confirm the pore size distribution by nitrogen adsorption and mercury porosimetry on resins partly swollen with water.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1984.021850604
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Supported Ziegler-Natta catalysts for propene polymerization: Grinding and co-grinding effects on catalyst improvement (1988)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 189 (1988), S. 549-558 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Solid ternary MgCl2/aromatic ester (A. E.)/TiCl4 catalysts are obtained by grinding MgCl2 followed by co-grinding MgCl2 and A. E. and then by TiCl4 impregnation. The productivity increases with grinding time up to a maximum value and the stereospecificity decreases continuously. A convenient choice of the A. E. improves the results. The productivity seems to be correlated with details of the pore size distribution. Infrared analysis of the catalyst reveals different ways of Ti-fixation but without clear relation to the catalytic properties.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1988.021890308
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...