Unsteady peeling accompanied by oscillations of adhesive tape from a soft adherend.

Peel angle dependence of the peel force was investigated using cross-linked polydimethylsiloxane (PDMS) covered with a pressure-sensitive adhesive tape. In our previous report, the peeling behavior at peel angles below 90° was discussed. The study revealed that an unsteady peeling occurs due to the extreme effects of the shear force on the adhered portion of the tape before the peeling starts.

Effects of degree of cross-links on adhesion curves of cross-linked polymers observed by a point-contact method.

The effects of degree of cross-links on the adhesion properties of polydimethylsiloxane (PDMS) were investigated with the use of a point-contact method in air at room temperature. The degree of cross-links, rho, was varied in a wide range, inducing changes in the rheology of the cross-linked PDMS from viscous solution to elastic gel, and the adhesion properties were examined by changing the separation velocity under a constant normal load and waiting period prior to separation. As a result, the adhesion force, F(A), strongly depended on rho and showed a maximum at a characteristic rho around the loss tangent (tan delta) = 1.