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  • 1
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Journal of the American Chemical Society 107 (1985), S. 5798-5800 
    ISSN: 1520-5126
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 120 (1984), S. 43-59 
    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: Die Polykondensationsreaktion von Polydimethylsiloxanen und α,ω-bifunktionellen Polystyrolen (oder substituierten Polystyrolen) verläuft sehr schnell, obwohl das Reaktionsgemisch heterogen ist. Im ersten Teil dieser Arbeit wird die Beziehung zwischen Reaktion und mikroskopischer Struktur des Gemisches qualitativ untersucht. Der zweite Teil ist dem mechanischen und thermomechanischen Verhalten der erhaltenen Block-Copolymeren gewidmet, deren Eigenschaften durch die Phasentrennung zwischen den unverträglichen Blöcken bestimmt werden.
    Notes: The polycondensation reaction between telechelic poly(dimethylsiloxanes) and α,ω-difunctional polystyrenes (or substituted polystyrenes) in toluene solution is very fast, in spite of the heterogeneous nature of the reaction medium. In the first part of the article is reported a qualitative approach of the condensation reaction in relation to the microscopic structure of the reaction medium. The second part is devoted to an investigation of the mechanical and thermomechanical behaviour of the multiblock copolymers which results from intramolecular phase separation.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Macromolecular Theory and Simulations 4 (1995), S. 1105-1126 
    ISSN: 1022-1344
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Hemibenzopinacolate radicals may be incorporated in a polymer chain and the latter used as a macromolecular initiator. Kinetics of polymerization are strongly dependent on the substitution of the pinacolate. A large family of substituted (CH3)3SiOC(C6H5)2 radicals has been synthesized and studied by electron spin resonance (ESR) and semiempirical molecular orbital calculations. ESR spectra are well resolved and, except for one derivative, allow an unambiguous determination of the hyperfine coupling splitting (HFS) constants. The ground state properties have been calculated within different approximations, namely MNDO, AM1 and PM3 for the geometry optimization and INDO for spin density. Geometries obtained within AM1 and PM3 approximations are satisfactory. The HFS constants evaluated using McConnell type relations and spin densities are in a quite good agreement with the experimental ones. It turns out that the effect of substitution on kinetics of polymerization cannot be attributed to any drastic change in the charge distribution.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 175 (1974), S. 2069-2077 
    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 preparation of (2,2-dimethyl-1,3-dioxolan-4-yl)methyl methacrylate is carried out using the reaction between a mixture of methacrylic acid and thionyl chloride with 2,3-O-isopropylideneglycerol in an HMPT/ether medium.Anionic polymerization of the obtained monomer yields linear polymers of low polydispersity, provided the experimental conditions are satisfactory.Using anionic block copolymerization, model-networks of poly[(2,2-dimethyl-1,3-dioxolan-4-yl)methyl methacrylate] [poly(4)] have been obtained with ethylene dimethacrylate as bifunctional second monomer. The obtained gels are characterized by the quasi-constant molecular weight of the elastic chains between two successive branch points.The acidic hydrolysis of the acetal functions of the linear poly(4) yields poly(2,3-dihydroxypropyl methacrylate).
    Notes: La préparation du méthacrylate de (diméthyl-2,2 dioxolann-1,3 yle-4) méthyle (4) a été mise au point par réaction en milieu HMPT/éther d'un mélange d'acide méthacrylique et de chlorure de thionyle avec l'O-isopropylidène-2,3 glycérol (3).La polymérisation anionique de ce monomère donne naissance à des polymères de faible polydispersité en masse moléculaire.Si le poly[méthacrylate de (diméthyl-2,2 dioxolann-1,3 yle-4) méthyle] [poly(4)] α,ω-d+arbanionique «vivant» est utilisé comme promoteur pour la polymérisation d'une +ible quantité de diméthacrylate d'éthylène, la réaction conduit à la formation de réticu+ +odèle homogènes caractérisés par la longueur quasi-constante de leurs éléments linéaires.L'hydrolyse acide de la fonction acétal du poly(4) linéaire conduit au poly(méthacrylate de dihydroxy-2,3 propyle).
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 183 (1982), S. 1181-1190 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: p-Trimethylsilylstyrene was found to be polymerisable anionically. When the reaction is carried out at low temperature in THF as solvent the polymer - poly(p-trimethylsilylstyrene) - is obtained in a quantitative yield and exhibits a low polydispersity. The glass transition temperature, viscosity-molecular weight relationships, and 1H and 13C NMR spectra were investigated in order to compare the influence of the trimethylsilyl group located at the benzene nucleus with respect to polystyrene and some other p-subtituted polystyrenes. The presence of the trimethylsilyl group in para position of the aromatic nucleus results in an increase of the rigidity of the polymer chain and in an increase of the glass transition temperature.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 183 (1982), S. 2787-2797 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The anionic polymerization of 1,3 and 1,4-diisopropenylbenzene (DIB) was found to be characterized by a rather low ceiling temperature and by rather strong differences in reactivity between the two double bonds. At low degrees of conversion the polymers formed are essentially linear and carry one pendant double bond per monomeric unit. Branching and crosslinking can occur only at higher conversion. 1,3-DIB can be copolymerized anionically with α-methylstyrene. Grafting reactions were carried out on polymer backbones with pendant unsaturated groups, using two different pathways. The occurence of coupling reaction can be avoided by a proper choice of experimental conditions.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 194 (1993), S. 3183-3193 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The reaction of plurilithiated polystyrenes with oxirane in the presence of N,N,N′,N′-tetramethylethylenediamine yields not only the expected polymers fitted with pendent 2-hydroxyethyl groups but also couples and branched products. The side reactions are rather important when using a stoichiometric amount of oxirane with regard to the lithiated sites but can be partly suppressed in presence of an excess of oxirane. A possible reaction pathway was established on the basis of a model reaction: under similar conditions the reaction of phenyllithium with oxirane leads to 2-phenylethanol and to a few percents of 3,4-diphenyl-1-butanol and 2-(3,4-diphenylbutoxy)ethanol. However, the presence of these two diphenyl derivatives among the reaction products may explain the existence of coupled and branched species in the functionalized polystyrene.
    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 179 (1978), S. 551-555 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Addition of two molecules of sec-butyllithium to one molecule of m-diisopropenylbenzene produces a bifunctional initiator which is soluble in non-polar solvents. This initiator is quite efficient for the polymerization of isoprene and butadiene and allows the preparation of samples of particular interest: bifunctional polydienes with high 1,4-cis and 1,4 contents, respectively, and by using a cross-linking agent elastomeric gels even after removal of the solvent.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 186 (1985), S. 1351-1364 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The reaction of sec-butyllithium with 1,1-bis(4-isopropenylphenyl)-1-phenyltridecane (3) yields carbanionic species which are soluble in a non-polar solvent. The long hydrocarbon “tail” of the molecule and the tendency of the organolithium compounds to associate may be the reason for the high solubility, possibly due to micel-formation. In the absence of any sidereaction, the addition reaction should lead to a difunctional organolithium compound. However, UV spectrometric measurements and characterization by size exclusion chromatography of the species obtained after protonation of the anionic sites, show that oligomerization accompanies the di-addition reaction with formation of principally dimeric and a small fraction of trimeric molecules. This implies the existence of di-, tri- and tetracarbanionic species in the “living” reaction media.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 189 (1988), S. 2521-2532 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: 1-Phenylethylpotassium (5), an efficient anionic polymerization initiator in tetrahydrofuran (THF) solution serving as a substitute for 1-methyl-1-phenylethylpotassium in most of its applications, was obtained by cleavage of bis(1-phenylethyl) ether (1) with potassium. Ether cleavage reactions were carried out in THF at mole ratios potassium/1 = 2/1 and 1/1, and the resulting solutions were submitted to careful analysis. All by-products formed in the reaction media were unambiguously identified and their mole fractions in the resulting mixture determined. The presence of these by-products was found not to influence the initiator efficiency.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
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