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  • 1
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 23 (1979), S. 927-939 
    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 texture and the pore size distribution of a set of styrene divinylbenzene copolymers, prepared by suspension polymerization with various compositions and various amounts of ethyl-2-hexanoic acid as diluent, have been studied using nitrogen adsorption-desorption isotherms, mercury porosimetry, and scanning-electron microscopy. It appears that pore volume and surface area may be well predicted in a large range of conditions (divinylbenzene contents between 20 and 60%, ethyl-2-hexanoic acid contents between 35% and 60%). In this range of conditions there are three structures: the elementary nuclei are spherical particles of about 100-200 Å in diameter. They are organized in microspheres of about 500-1000 Å, and the microspheres form aggregates (2500-5000 Å) more or less separated by large holes. The smaller pores (〈40 Å) are in the microspheres, between the nuclei; they are present only if the amount of divinylbenzene is high enough. Intermediate pores (40-500 Å) are, in the aggregates, between the microspheres, although the larger pores between the aggregates range from about 500 Å to more than 10,000 Å, depending on the amount of diluent.
    Additional Material: 13 Ill.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 106 (1982), S. 67-77 
    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: Abhängig von der Menge an porenerzeugender Substanz (Toluol) oder Vernetzer (Divinylbenzol), führt die Suspensionscopolymerisation von Styrol-Divinylbenzol (DVB) - Vinylbenzylchlorid (VBC) zu gelartigen oder makroporösen Harzen. Der teilweise Ersatz von Styrol durch VCB ändert nur unwesentlich die Morphologie der Harze. Eine ziemlich scharfe Grenze wird zwischen den zwei Harzen beobachtet, makroporöse Harze können als kleine Bereiche hochvernetzten Materials betrachtet werden, die durch lose Ketten verbunden sind, die im trockenen Zustand gestreckt (enge Verteilung sehr kleiner Poren) und im gequollenen entspannt sind und so die sehr hohe Quellung erklären, die in Lösungsmitteln oder in Nichtlösern beobachtet wird.
    Notes: Depending on the amount of porogenic (toluene) or crosslinking (divinyl benzene) agent, the suspension copolymerization of styrene-divinyl benzene (DVB)  -  vinyl benzylchloride (VBC) leads to gel type or macroporous resins. Partial replacement of styrene by VBC does not change much the morphology of the resins. A rather sharp boundary is observed between the two kinds of resins, macroporous resins can be visualized as small nodules of highly crosslinked material linked by loose chains strained in the dry state (narrow distribution of very small pores) and relaxed in the swollen state, thus accounting for the very high swelling ratio observed either in the solvent or in nonsolvent.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 80 (1979), S. 31-51 
    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: Les résines macroporeuses styrène-divinylbenzène préparées en présence d'agents réticulants comme porogènes ont été étudiées. Une définition du domaine macroporeux est donnée en se fondant sur l'homogénéité des propriétés et des structures. L'existence de ce domaine macroporeux apparaît comme un des traits caractéristiques des résines macroporeuses. La position de ce domaine est donnée pour 4 porogènes differénts. L'évolution de la texture des résines est analysée et discutée en fonction de leur localisation à l'intérieur ou à l'extérieur du domaine macroporeux.
    Notes: Macroporous styrene-divinylbenzene resins are studied using precipitating agents as diluents. A definition of the macroporous domain is given, based on homogeneous properties and structures. The existence of this macroporous domain is proved to be a general feature of the macroporous resins field. The position of this domain is specified for 4 different diluents. The evolution of the texture of the resins, according to their position inside or outside the macroporous domain is analyzed and discussed.
    Additional Material: 16 Ill.
    Type of Medium: Electronic Resource
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