Formation of Multiple Networks in Cis-1, 4-Polybutadiene: Dynamical Viscoelasticity, Gel Content and Cross-Link Density

Abstract

Abstract The formation of multiple networks of cis-1, 4-polybutadiene rubber (BR) with sulfur and carbon black (CB) were discussed by analysing the curing curve, gel content, cross-linking density (XLD) and dynamic viscoelasticity. XLD and gel test show the network from chains entanglement and sulfur cross-link existing in unfilled BR, in addition there is another network from CB in filled BR. Networks from sulfur and CB cross-links has two different peaks of loss modulus (G”) and loss tangent at different dynamic strain. Furthermore, the average bonding number of each chain to form the network is calculated from the sulfur cross-link density. There is two percolation of G‘0.01Hz or gel content as the average bonding number increased in curing.