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
Filter
  • Polymer and Materials Science  (2)
Collection
Publisher
Years
  • 1
    ISSN: 0887-6266
    Keywords: optically active polymers ; gel permeation chromatography ; laser light scattering ; GPC calibration ; rodlike conformation ; Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: By combining the offline static and dynamic laser light scattering (LLS) and gel permeation chromatography (GPC) results of a broadly distributed polymer sample, we were able to characterize a series of chiral binaphthyl-based polyarylenes and poly(aryleneethnylene)s in THF at 25°C. For each of the samples, we obtained not only the weight-average molar mass Mw, the second virial coefficient A2 and the z-average translational diffusion coefficient 〈D〉, but also two calibrations: V = A + Blog(M) and D = kD M-αD, where V, D, and M are the elution volume, the translational diffusion coefficient and the molar mass for monodisperse polymer chains, respectively, and A, B, kD, and αD are four calibration constants. Using these calibrations, we estimated the molar mass distributions of these novel polymers. We showed that using polystyrene to calibrate the GPC columns could lead to a smaller Mw. Our results indicate that all the polymers studied have a rigid chain conformation in THF at 25°C and the introduction of the  - NO2 groups into the monomer can greatly promote the polymer solubility in THF.© 1998 John Wiley & Sons, Inc. J. Polym. Sci. B Polym. Phys. 36: 2615-2622, 1998
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Macromolecular Chemistry and Physics 199 (1998), S. 2395-2401 
    ISSN: 1022-1352
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: A chiral binaphthyl monomer (R)-9a that contains a terminal alkyne and an aryl iodide function has been synthesized. Homopolymerization of (R)-9a in the presence of Pd(PPh3)4/Cul catalysts leads to the formation of polymer (R)-6. This polymer represents a new type of chiral conjugated materials with the dipole units oriented into one direction along the rigid polymer chain. Materials of this structure may have interesting nonlinear optical properties. (R)-6 is soluble in common organic solvents. Gel permeation chromatography (GPC) analysis shows Mw = 34000 and Mn = 17000 (polydispersity index PDI = 1.97). Its specific optical rotation is [α]D = -197.6 (c = 0.16, CH2Cl2). At lower concentration of (R)-9a, self-coupling produces a series of multipolar chiral macrocycles.
    Additional Material: 1 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...