ISSN:
1435-1536
Keywords:
Dielectric relaxation
;
time-domain spectrometry
;
KWW function
;
PMMA
;
NBR
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 The time-domain dielectric response (after-effect) of poly(methyl methacrylate) (PMMA) and nitrile butadiene rubber (NBR) to a voltage step (100 V) was measured at varying temperatures. From the variation of the sample capacitanceC with time, we determined the ratioF d/ΔC, withF d=(dC/dlnt)max and ΔC denoting the difference between the initial and the extrapolated equilibrium capacitance values. For PMMA around room temperature (RT) this ratio assumed values similar to those reported for mechanical stress relaxation. With NBR, such values were observed only at temperatures significantly below RT. A modified Kohlrausch-Williams-Watts (stretched exponential) function provided a good fit to the measuredC(t) data.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00660090
