A NEW MOLECULAR THEORY OF RUBBER ELASTICITY WITH CONSTRAINTS OF JUNCTIONS AND TRAPPED ENTANGLEMENTS

A new molecular theory of rubber elasticity with constraints of junctions and trapped entanglements is presented. It succeeds in relating the elastic equation of state to molecular constitution by three molecular quantities (C₁₀₀, C₀₂₀ and C₂₀₀), in which the severity of junction and entanglement constraints are characterized by two important parameters Φ_Ac and Φ_Ae. The theoretical stress to strain curves for five types of deformation derived from this theory were all verified by experiments. It shows that this theory can predict the rubberlike elasticity quantitatively and can explain the role of entanglement and the dependence of the reduction of junction fluctuations on the functionality （f） and Φ_A.