| Abstract: | The miscibility between an acrylic copolymer and a tackifier resin was investigated in terms of phase diagrams, glass transition temperatures (Tg's), and dynamic mechanical properties of blends. Shear creep resistance (holding power, tb) of the blends was measured as a function of both temperature and stress (σ0) in order to obtain the master curves. It was found that the shear creep resistance of the pressure-sensitive adhesives (PSAs) was closely related to the miscibility between the components and viscoelastic properties of the blends. The master curve of the miscible blends shifts toward a longer time scale as the amount of tackifier resin in the blend is increased as a result of the modification of the bulk properties, and their behavior greatly depends on the glass transition temperature (Tg) and storage modulus (G′) of the blends. However, the master curve of immiscible blends where two phases exist in the system does not shift greatly toward a longer time scale, because Tg and the storage modulus of the blend do not change greatly. © 1995 John Wiley & Sons, Inc. |
