ISSN:
0887-6266
Keywords:
blends, polystyrene/poly (vinyl methyl ether), rheology near phase transition in
;
rheology of polystyrene/poly (vinyl methyl ether) blends near phase transition
;
viscoelasticity of blends near critical point
;
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
Mixtures are expected to show anomalous behavior in their viscoelastic properties close to a critical point. In this study, the reheological behavior of blends of polystyrene and poly (vinyl methyl ether) below, close to, and above the phase separation temperature Ts was investigated. Rheological measurements were carried out at three different compositions in the melt. Below and far from Ts, a satisfactory superposition of the storage and loss moduli G' and G″ was observed at all temperatures and frequencies. Close to Ts deviations were observed for G' at low frequencies (the so-called terminal zone). Above Ts G″ values was still observed over the whole range of frequencies and temperatures. The deviations observed for G' near Ts can be interpreted as due to the presence of significant concentration fluctuations. Plots of log (G'/G″2) as a function of temperature were shown to be sensitive to this anomalous behavior.
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/polb.1991.090291301
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