ISSN:
1436-2449
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
Summary In this work are examined changes of the α relaxation spectrum of PMA during the structural relaxation process which follows a quenching from a temperature To above Tg to another T1 below Tg, which is mantained constant. It is found that the relaxation times spectrum is shifted towards longer times as the ageing time increases. At the same time, its form becomes more and more wide, approaching the form of the relaxation times spectrum calculated at temperatures above Tg from alternative dielectric measurements. A parameter measuring the shift of the spectrum, a(ta), is defined and its dependence on ageing time and annealig temperature is studied. The effective relaxation time of the structural relaxation process is calculated from a(ta) and it is found dependent on the temperature of annealing as well as on the value of a(ta)itself.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00254914
