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  • 1
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1011-1019 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The characteristics of the photoinduced electron transfer reaction from polystyrene pendant tris(2,2′-bipyridyl)ruthenium (II) complex [Ru(bpy)32+] to methylviologen (MV2+) were studied. The rate constant k1 from the excited state of the complex, Ru(bpy)32+*, to MV2+ were determined for both the polymeric and monomeric complexes from the lifetime τ of Ru(bpy)32+* and the quenching rate of Ru(bpy)32+* by MV2+. The polymer pendant Ru(bpy)32+* showed three kinds of τ components ranging from 7 to 474 ns, in contrast to the monomeric complex, which showed one component of 350 ns. The k1 values for both complexes were almost the same, on the order of 108 L/mol s. The photoinduced electron transfer from solid-phase Ru(bpy)32+ to liquid-phase MV2+ was realized by utilizing the polymer complex, and the solid-liquid interphase reaction system is discussed.
    Additional Material: 7 Ill.
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  • 2
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 13 (1975), S. 2581-2590 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Spiro[2,4]hepta-4,6-diene, a derivative of cyclopentadiene, was polymerized at -76°C with various triphenylmethyl salts as initiator. The polymer consists only of the 1,2- and 1,4-addition structures, and their contents can be determined by the relative area of the olefin proton peaks. The polymer structure changed characteristically with the polymerization conditions. The content of 1,4-structure decreased with increasing polarity of the medium from 45-70 in toluene to 25-30% in 7:3 CH2Cl2-CH3CN. In 1:1 CH2Cl2-toluene, the 1,4-structure content decreased from 70% to 40% with increasing radii of counteranions. These results were interpreted according to the model of the cationic propagation proposed earlier, as arising from the different tightness of the propagating ion pair. In the case of pentacoordinate counteranions, in particular SnCl5-, the 1,4-structure content was greater than expected from the anion size alone and decreased with increasing initiator concentrations, in contrast with the behavior of the other tetra- and hexacoordinate anions. This was attributed to the possibly facile aggregation of the pentacoordinate anion. However, the common ion effect was not observed.
    Additional Material: 4 Ill.
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  • 3
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 14 (1976), S. 1221-1234 
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Dynamic viscoelastic measurements, E′ and E″, were carried out on solution-crystallized and melt-crystallized samples of fractionated isotactic polypropylene over the temperature range of -100°C to 150°C. The molecular weight ranged from 1.26 × 104 to 1.77 × 105. The effects of swelling and annealing on the α and β peaks were more pronounced for the lower molecular weight fraction than for the higher one. It was found that both the untreated solution-crystallized and quenched melt-crystallized samples contain a fair amounts of a constrained amorphous phase in which the molecular motions were so depressed that the corresponding peak could be observed as the low-temperature component of the α peak. These constraints on the molecular motions are considered to originate from the spatial restrictions imposed by the presence of the surrounding crystallities.
    Additional Material: 10 Ill.
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  • 4
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 18 (1980), S. 2149-2153 
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 3 Ill.
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  • 5
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 12 (1974), S. 2267-2280 
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The effects of swelling and annealing treatments on viscoelastic behavior were studied in melt-crystallized and solution-crystallized samples of isotactic polypropylene (iso-PP) over the temperature range -150 to 150°C. The log E″ versus T curves exhibited α, β, and γ peaks in order of decreasing temperature. The β peak of the melt-crystallized sample shifted to higher temperatures after annealing, but was not affected by swelling. The α peak of melt-crystallized polymer was affected by swelling treatments. It increased in height and shifted to lower temperatures almost linearly with the volume fraction of absorbed solvent. The magnitude of the shift was independent of the solvent species - toluene, p-xylene, tetralin, carbon tetrachloride - however, it depended significantly on the temperature at which the sample had been heat treated. For solution-crystallized polymer, no peaks in log E″ were observed in the temperature range of the β peak of melt-crystallized material, but the α peak appeared larger and broader, and at higher temperature than the corresponding peak in the melt-crystallized polymer. After swelling or annealing, the low-temperature component of the α peak of the solution-crystallized sample decreased in height and at the same time a new loss peak appeared at -55 and 0°C, respectively, is swollen and annealed samples. In particular, in the case of annealing treatments, the high-temperature component of the α peak shifted to still higher temperatures. From these results on the solution-crystallized sample it can be deduced that the segmental motions in the amorphous phase are very strongly constrained by surrounding crystalline phases as compared with those in the amorphous phase of the melt-crystallized sample, and the constraints imposed on the segmental motions are released to a great extent by both treatments. Finally, swelling effects on the γ peak were examined. The γ peak of the melt-crystallized sample decreased in height after swelling. On the other hand, the γ peak of the solution-crystallized sample separated into two peaks, which might be attributed to the mechanical relaxations in the crystalline and amorphous phases.
    Additional Material: 9 Ill.
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  • 6
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science Part A-2: Polymer Physics 9 (1971), S. 1629-1640 
    ISSN: 0449-2978
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The sorption properties of atactic polypropylene (APP) and isotactic polypropylene (IPP) were studied by equilibrium sorption of various organic solvents. The variation of the Flory-Huggins interaction parameter χ for the APP-CCl4 system at 25°C was expressed as a function of the volume fraction v2 of polymer by the relation: x = 0.113 exp {1.879 v2}. The average molecular weight Mc of the polymer chains between successive crystallites for IPP subjected to different thermal treatments was calculated to be 250 to 350 by the equation of Flory and Rehner. From the variation of Mc with solvent concentration, we estimated the number fraction of polymer chains actually contributing to elastic deformation. The clustering function for solvent in the polymer calculated by the method of Zimm and Lundberg decreased linearly from a positive value to -1 with increasing solvent concentration. Clustering of solvent molecules was found to occur more easily in APP than in IPP.
    Additional Material: 6 Ill.
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  • 7
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science Part A-2: Polymer Physics 9 (1971), S. 431-435 
    ISSN: 0449-2978
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The effects of stereoregularity on the low-temperature relaxation processes were studied by dynamic mechanical measurements on isotactic and syndiotactic polyisobutyl methacrylates (iso-PiBMA and syn-PiBMA). The α, β, and γ relaxation processes were observed in both stereoregular forms. Both the α, and β loss peaks were at lower temperatures for iso-PiBMA than for syn-PiBMA. The γ loss peak was observed at about -155°C at 30 Hz for both forms, and the apparent activation energy of this process was same for both samples within experimental error (6.7 ± 0.5 kcal/mole). It was reduced from these results that the α and β processes are both considerably influenced by the isotactic configuration but the γ process is not.
    Additional Material: 2 Ill.
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  • 8
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 67 (1934), S. 1011-1021 
    ISSN: 0365-9631
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 4 Tab.
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  • 9
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 68 (1935), S. 570-581 
    ISSN: 0365-9631
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 69 (1936), S. 2238-2242 
    ISSN: 0365-9631
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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