M. Kluppel, NETWORK STRUCTURE AND MECHANICAL-PROPERTIES OF ELASTOMERS .2. INFLUENCE OF STRESS-INDUCED CRYSTALLIZATION ON STRESS-STRAIN DATA, Kautschuk und Gummi, Kunststoffe, 47(4), 1994, pp. 242-247
Uniaxial stress-strain properties of thiuram-cured natural rubbers are
discussed in the framework of a non-Gaussian network model. The finit
e extensibility component of the reduced stress is evaluated by using
a series expansion of the inverse Langevin function. From the resultin
g Gaussian contribution to the reduced stress, the effect of stress-in
duced crystallization on stress-strain data Is extracted by comparing
measurements at room temperature (24-degrees-C) and 80-degrees-C, It i
s seen that at 24-degrees-C stress-induced crystallization leads to po
sitive deviations from the linear behavior of the Gaussian contributio
n to the reduced stress in Mooney-Rivlin plots for extensions larger t
han about 100 %-200 %. At extensions larger than about 400 %, the obse
rved deviations increase very rapidely and stress-induced crystallizat
ion becomes dominant A qualitative different picture is found for the
measurements at 80-degrees-C, which means that stress-induced crystall
ization is not significant at this temperature.