TY - JOUR
T1 - SUPERPOSITION OF SMALL DEFORMATIONS ON LARGE DEFORMATIONS
T2 - MEASUREMENTS OF THE INCREMENTAL RELAXATION MODULUS FOR A POLYISOBUTYLENE SOLUTION.
AU - McKenna, G. B.
AU - Zapas, L. J.
PY - 1985
Y1 - 1985
N2 - The incremental relaxation modulus DELTA G(t) for a concentrated solution of polyisobutylene has been determined from step-shear experiments in which a small deformation DELTA gamma was superimposed on a large deformation gamma //1; DELTA G(t) was found to decrease with increasing gamma //1 and to increase with the time t//e after the imposition of the large deformation. It was also observed that the 'apparent relaxation spectrum' associated with DELTA G(t) narrows and shifts to shorter times when compared to the spectrum associated with the linear viscoelastic relaxation modulus G(t). The results are well described by the nonlinear constitutive equation of the BKZ elastic fluid theory.
AB - The incremental relaxation modulus DELTA G(t) for a concentrated solution of polyisobutylene has been determined from step-shear experiments in which a small deformation DELTA gamma was superimposed on a large deformation gamma //1; DELTA G(t) was found to decrease with increasing gamma //1 and to increase with the time t//e after the imposition of the large deformation. It was also observed that the 'apparent relaxation spectrum' associated with DELTA G(t) narrows and shifts to shorter times when compared to the spectrum associated with the linear viscoelastic relaxation modulus G(t). The results are well described by the nonlinear constitutive equation of the BKZ elastic fluid theory.
UR - http://www.scopus.com/inward/record.url?scp=0042021659&partnerID=8YFLogxK
U2 - 10.1002/pol.1985.180230816
DO - 10.1002/pol.1985.180230816
M3 - Article
AN - SCOPUS:0042021659
VL - 23
SP - 1647
EP - 1656
JO - Journal of polymer science. Part A-2, Polymer physics
JF - Journal of polymer science. Part A-2, Polymer physics
SN - 0449-2978
IS - 8
ER -