A novel approach to prepare a gradient polymer with a wide damping temperature range by in-situ chemical modification of rubber during vulcanization

Based on the fact that rubber can be chemically modified by sulfur, and sulfur can diffuse into rubber driven by a concentration gradient and chemical reaction, a new approach for the preparation of a polymer with a gradient from rubbery to glassy phase has been developed using the sulfur-vulcanization reaction of rubber. The gradient polymer obtained exhibits a wide transition range spanning over 100°C with a peak half-width of 69°C. The mechanism of forming the gradient structure is also discussed.