Variation of the States of Rubber

2.The States of Rubber : State of Rubber and Tensile Properties

Abstract

The relations between the tensile properties of filled rubbers and the states of filled rubber are discussed.
Crosslinking in terms of stress can be estimated most properly with the stress at 100% strain M₁₀₀. The variation of M₁₀₀ among the rubbers with the same formulation originates from those of crosslink density, due to variation of crosslinking in the bound rubber, and filler volume effect, due to variation of dispersion.
Unique relations exist between the extension ratio at break λ_b and M₁₀₀; With amorphous polymers, λ_b = A M₁₀₀^–0.75. With crystalline polymers, λ_b = A’ M₁₀₀^–0.25.