Rubber composition

Abstract

A rubber composition is provided comprising a rubber component and a water-absorbing agent, wherein the rubber composition is a reversible rubber composition whose physical properties change reversibly between a water-absorbed state and a dry state, wherein a rectangular parallelepiped specimen with a length of 30 mm, a width of 20 mm and a thickness of 2 mm, cut from the rubber composition, exhibits a water absorption rate VWAB of 0.020 g / day or more from the dry state and an evaporation rate VWEV of 0.030 g / day or more from a water-saturated state, and wherein a ratio, tan δSAT / tan δDRY, of a loss factor in the water-saturated state at 30 °C, tan δSAT, to a loss factor in the dry state at 30 °C, tan δDRY, is 1.05 or more.The aim of the present invention is to improve adhesion under conditions in which dry and wet conditions alternate.