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
    Die kristallisation eines geschmolzenen molekülkomplexes aus hochmolekularem polyoxyethylen und harnstoff (1992)
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 195 (1992), S. 165-170 
    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: The structural transformation of a molecular complex (MC) of polyoxyethylene and urea on cooling from the molten state has been investigated by DSC and X-ray analysis. A high-temperature polymorphic from of the MC was found to be formed, which transforms into the known crystal form of the MC with a hexagonal crystal modification on cooling.
    Notes: Die Strukturveränderungen eines Molekülkomplexes (MK) aus Polyoxyethylen und Harnstoff beim Abkühlen aus dem geschmolzenen Zustand werden kalorimetrisch und röntgenographisch untersucht. Es wird festgestellt, daß eine polymorphe Hochtemperaturform des MK entsteht, die beim Abkühlen in die bekannte Kristallform des MK mit hexagonaler Kristallmodifikation übergeht.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/apmc.1992.051950113
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Phase transformation on heating of undercooled melt of poly(ethylene oxide)-urea molecular complex (1994)
    Weinheim : Wiley-Blackwell
    Macromolecular Chemistry and Physics 195 (1994), S. 2227-2231 
    Details
    ISSN: 1022-1352
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: X-ray and calorimetric investigations of the structure and transformations on heating of quenched (undercooled) samples of poly(ethylene oxide)-urea molecular complexes are discussed. It was established that at room temperature the undercooled melt of the molecular complex contains free urea in a tetragonal crystal modification and a high-temperature poly(ethylene oxide)-urea molecular complex whose crystal modification does not coincide with the known hexagonal crystal structure of the molecular complex obtained from solution or by slow cooling from the melt. It was shown that on heating this molecular complex to a temperature between 87,5 and 90°C, the hexagonal crystal modification, stable at room temperature, is obtained.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1994.021950628
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Complexation of poly(ethylene oxide) and urea (1994)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part B: Polymer Physics 32 (1994), S. 387-394 
    Details
    ISSN: 0887-6266
    Keywords: poly(ethylene oxide) ; urea ; molecular complex ; infrared spectroscopy ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The complexation of ultrahigh-molecular-weight poly(ethylene oxide) (PEO) with urea in both the solid and molten states was studied by infrared spectroscopy. Information about the temperature dependences of the absorption bands in the 3600-2600 and 1300-600 cm-1 region on heating and cooling was obtained. Some conclusions concerning the interaction between PEO and urea were also made. The formation of a high temperature, metastable molecular complex between PEO and urea, which is susceptible to undercooling, was confirmed spectroscopically. Heating to 85-90°C resulted in a molecular complex stable at room temperature.© 1994 John Wiley & Sons, Inc.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/polb.1994.090320222
    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...