The effect of bond formation on the tack of polymers

The tack of polymers to be used as adhesives is measured by a two-stage process of bond formation and bond separation. Bond formation is governed by the contact time, the contact force, the roughness of the surfaces, surface and interfacial tensions, and the mechanical or viscoelastic properties of the adhesive and substrate. This paper presents experimental studies of the contact formation of various model polymers on steel surfaces with well-defined and different degrees of roughness. The tack was measured with an instrument of the probe tack type, which determines the adhesive (interfacial) fracture energy per unit of interface as a measure of the tack and by means of which the most important parameters during bond formation and separation, such as the contact time, contact force, rate of separation, and temperature, can be adjusted and measured over sufficiently wide ranges. In the typical time interval for the contact time, the polymers are found in the plateau range of their viscoelastic spectrum. T...