UNIVERSAL SCALING BEHAVIOR OF THE TACKINESS OF POLYMER MELTS

Abstract

ABSTRACTTack properties of nine linear polyisoprenes (PIPs) with molecular weights ranging from 84 to 476 kg/mol and two star-branched PIPs with molecular weights ranging from 609 to 1130 kg/mol were investigated on various surfaces, such as stainless steel, aluminum, copper, quartz, and plastics. In the investigation, a finger-sized cylindrical rod having a flat end face was brought into contact with a PIP polymer. After equilibrium was reached, the cylindrical rod was removed from the substrate at a constant pull-off velocity, Vs. We found that when the pulling speed (Vs) is greater than a critical speed (Vc), the maximum tack force (Fmax) can be generally described by the following scaling relationships: Fmax ∼ Vs1/3 and Fmax ∼ tmax−1/2, where tmax is the time when the maximum force is reached in the force–time profile. Remarkably, this scaling behavior of the tackiness appears to be universal, as it is independent of the adhered surface preparation, the molecular weight distribution, and the linear or branched chain structure of a polymer melt.