ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

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
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 1304-1312 
    ISSN: 0032-3888
    Keywords: Chemistry ; Chemical Engineering
    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: We have determined the degree of stiffness of a poly(γ-benzyl α, L-glutamate) (PBLG) chain in benzyl alcohol by measuring the intrinsic viscosities of dilute Solutions with differing molecular weights. Viscoelastic properties in oscillatory shear flow have been studied and the dependence of the loss and storage moduli on temperature, composition, and frequency are reported. We have also studied the transient shear stress relaxation behavior of the PBLG gel at different temperatures and concentrations. A comparison has been made between these gels and a classical poly(dimethyl siloxane) (PDMS) network, as well as, typical glassy polymers. Shear creep and recovery measurements have been made for this system. Some extensional step strain experiments using lubricated squeezing have been investigated. Tensile experiments have been made to determine stress-strain relationship during elongation. Preliminary experiments using the impulse approach to viscoelasticity further indicate the high elastic contribution in the gel.
    Additional Material: 13 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 44 (1992), S. 2115-2125 
    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: We report the concentration and temperature dependencies of the diffusion coefficients obtained from dynamic light-scattering studies for the poly(γ-benzyl α, l-glutamate)-benzyl alcohol (PBLG-BA) system. These studies were made at dilute and semidilute polymer concentrations, mainly in the isotropic phase. The measured translational and rotational diffusion coefficients in dilute solutions are consistent with predictions based on wormlike chain models. The mutual diffusion coefficient in semidilute solutions shows a marked deviation from scaling predictions, demonstrating the strong coupling between the translational and rotational motions. The measured time evolution of the scattered intensity after the PBLG-BA system is suddenly quenched into the gel phase demonstrates that aggregation is a significant mechanism in the formation of the gel phase.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part B: Polymer Physics 29 (1991), S. 1373-1387 
    ISSN: 0887-6266
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The cholesteric mesophase of the PBLG-BA system in concentrated solutions and in the gel phase has been investigated by static laser light scattering. The observed ‘distortion’ of the patterns in terms of their dependence on the azimuthal angle was studied. Effect of form-optical rotation on the pattern is discussed. The manner of distortion in the Hv pattern determines the sense of cholesteric twisting. The observed scattering patterns are analogous to those obtained by previous investigators in other solvents. Quantitative measurements of the intensity as a function of scattering vector provide information on the sense and pitch of the cholesteric twisting, as a function of temperature and concentration. Optical microscopy studies reveal onset and build-up of the cholesteric structure. Optical rotation and differential scanning calorimetry (DSC) studies support the conclusions obtained from light-scattering experiments.
    Additional Material: 19 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part B: Polymer Physics 34 (1996), S. 649-656 
    ISSN: 0887-6266
    Keywords: liquid crystalline polymer ; quasielastic neutron scattering ; gelation ; rotational dynamics ; poly(γ-benzyl L-glutamate) ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Quasielastic neutron scattering has been used to study the motion of protons in two solutions of poly(γ-benzyl L-glutamate) (PBLG) and deuterated benzyl alcohol (DBA) as they are brought from the high temperature (cholesteric and isotropic) phase towards the gel. Quasielastic neutron scattering results demonstrate that, in both the isotropic and cholesteric phases, the local rotational dynamics of the polymer are continuous in the high temperature phases, but become more constrained as the system approaches and enters the gel phase. The results also show that the energetics of the rotational motion of the protons below the gelation threshold are independent of the initial phase and the protons are not rendered immobile in the gel phase. © 1996 John Wiley & Sons, Inc.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Letters Edition 28 (1990), S. 247-252 
    ISSN: 0887-6258
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...