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:
The viscoelastic properties of aqueous solution of methylcellulose were investigated using three types of rheometers, which enabled us to cover more than 8 decades of frequency range. At first, the entanglement density X/q at various temperatures was estimated by comparing G′, and G″ curves and relaxation spectra experimentally obtained with those calculated from Hayashi's theory. At lower temperatures, the concentration dependence of X/q was small as observed for polyelectrolytes, but increased at higher temperatures. The same tendency was observed in the concentration dependence of the entanglement function GeN. It is supposed that water molecules adsorbed on methylcellulose and depressing the entanglement formation dissociate with increasing temperature. The relaxation mechanism was then examined from the concentration dependences of G′, η′, and ηo at various temperatures and frequencies. It is concluded that the structural networks in a solution become closer with increasing temperature, and the corresponding viscoelastic mechanism varies from the intermolecular interaction such as entanglements to the intramolecular motion with increasing frequency.
Additional Material:
17 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/app.1973.070170222
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