ISSN:
1435-1536
Keywords:
Photon correlation spectroscopy
;
orientation relaxation
;
rotational diffusion
;
hairy rod polymers
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract Photon correlation spectroscopy in the depolarized geometry was employed to measure the orientation relaxation correlation functionC(q,t) in poly(p-2,5-dodecyl-1,4-phenylene)/toluene solutions at different scattering wavevectorsq. The large optical anisotropy of this hairy rod molecule with an average lengthL=117 nm allowed a detailed analysis of both amplitude and shape ofC(q,t) that revealed two mechanisms for relaxing the orientation fluctuations in the concentrated regime (10〈cL 3〈230). The comparison of the rotational diffusivity and the anisotropic scattering intensity with theoretical, simulation and experimental results of rigid rods indicated quantitatively different behavior for the present stiff-chain bearing two long side groups per repeating unit.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00654176
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