of the Peeling of
and other Elastomers
Coloplast Research, Bakkegardsvej
406A, DK-3050 Humlebaek, Denmark.
Dept. Mechanical Engineering,
77 Mass. Avenue, Cambridge
MA 02139, USA
The transient extensional
viscosity of a polyisobutylene (PIB)-based pressure-sensitive adhesive
(PSA) is measured in a filament stretching instrument at three stretch
rates, and compared with theoretical predictions based on the linear viscoelastic
(LVE) properties of the PSA and the use of linear and non-linear constitutive
equations. Based on previously reported adhesive stretch rate profiles
across the peel front, a model predicting peel force from peel rate is
proposed and evaluated for each constitutive equation. A new expression
for the relative contributions of the individual relaxation modes of the
polymeric material to the total measured peel force is derived and the
result is discussed with regard to correlation of LVE data to peel performance.
Comparison of predicted and measured peel force values reveals that peeling
of this PSA is only qualitatively described by linear viscoelasticity;
quantitative agreement is obtained when the strain-hardening behaviour
of the adhesive is properly modelled.
J. Adhesion & Adhesives, 18(5), 1998, p. 333-343