Influence of miscibility between the base polymer and the tackifier in acrylic pressure-sensitive adhesives upon the rate-dependence of their rolling friction coefficient

摘要

In this study, the influence of miscibility between the components in acrylic pressure-sensitive adhesives upon the rate-dependence of their rolling friction coefficient has been clarified. In case of miscible blend systems, incorporation of a tackifier resins into the pressure-sensitive adhesives resulted in the systematic modification of the rolling friction coefficient. Each rolling friction coefficient vs. velocity (fvs. log v) curve had two peaks or shoulder at some rates. Cohesive failure occurred in lower rate side of the lower peak, and interfacial failure or stick-slip occurred in higher rate side of the higher peak, and complicated mixed failure occurred between two peaks. As the concentration of the tackifier became higher, the peaks of the curves shifted toward lower rate. In case of immiscible blends where two phases existed in the system, as tackifier content became higher, the curves did not vary greatly along the rate axis, but the absolute value of rolling friction coefficient decreased. It is evident that rolling friction coefficient mostly depends upon the viscoelastic properties of the matrix phase, and that a dispersed phase acts as a kind of filler.