Relationship between Viscoelastic and Peeling Properties of Model Adhesives. Part 1. Cohesive Fracture

Micromechanisms of Tack of Soft Adhesives Based on Styrenic Block Copolymers

“…On the first question, it has been shown that the shift in time of certain characteristic relaxation times of a polymer led to a shift of the same magnitude in the debonding rate at which a transition from cohesive to adhesive failure was observed in peel tests, implying therefore that the rheological properties of the adhesive control its adhesive behavior. [49,50] On the second question, however, a direct prediction of r max , e max or W from the small-strain viscoelastic properties and a surface property such as the surface tension of the substrate is currently not possible. According to recent studies, [24,51,52] a quantitative prediction of peel forces of fibrillating adhesives requires data on the elongational properties of these polymers.…”

Micromechanics of flat-probe adhesion tests of soft viscoelastic polymer films

“…This problem is really a problem of a uniaxial tensile test (in solid mechanics terms) or of an elongational flow (in fluid mechanics terms). 12,41 The behavior of an adhesive in this regime will be closely related to its molecular structure, and although a detailed description of the structure-property relationship is beyond the scope of this article, several remarks can be made.…”

“…However, the mechanism of separation between adhesive and substrate for a typical soft adhesive can be quite complex and involves highly nonhomogeneous deformation and formation of fibrils. 9,[11][12][13] These fibrils strongly modify the stress field at the crack tip and make a micromechanical analysis of the fibril formation very difficult.…”

Molecular and nanoscale factors governing pressure‐sensitive adhesion strength of viscoelastic polymers

“…Moreover, cohesive and interfacial types of adhesive debonding also relate to the linear elastic properties of the PSAs. [8][9][10][11] In 1996, de Gennes 18 proposed a simple theoretical picture, known as the trumpet model, to explain the strong adhesion properties of weakly crosslinked rubbers. This model qualitatively describes the transition between the cohesive fracture domain and the interfacial fracture domain observed in peeling experiments performed with lightly crosslinked elastomers typically used for soft adhesive applications.…”

“…[5][6][7][8][9][10][11][12][13][14][15][16] The designation ''pressure-sensitive adhesion'' attributes the behavior of PSAs to their rheological nature and the contribution of shear deformation under compressive adhesive-bonding, and adhesion strength can be predicted from rheological behavior of the PSAs in the linear domain. 5,[10][11][12]16 Time-temperature equivalence, a typical feature of rubber-like polymers, 17 applies to all PSAs, [6][7][8][9][10][11]13,14 indicating that they are viscoelastic materials. Moreover, cohesive and interfacial types of adhesive debonding also relate to the linear elastic properties of the PSAs.…”