Mechanical Properties of Slide-ring Materials

The chapter describes the mechanical properties and stretch-induced swelling properties of the slide-ring gels. After a brief review of conventional rubbers and gels, with the historical background, the most important features of the slide-ring materials are introduced: the pulley effect and the entropy of the rings, which yield the peculiar mechanical properties of the slide-ring materials, which are quite different from usual rubbers and gels with fixed cross-links. These two competitive effects result in the sliding elasticity, and low Young's modulus of the slide-ring materials, which is evaluated theoretically here. Subsequently, some anomalies in the experimental results of viscoelastic profiles, biaxial tensile properties, and stretch-driven volume changes are reviewed, which support the existence of the pulley effect and the entropy of the rings.