Neutron scattering has shown the first diffraction peak in the structure factor of a 1,4-polybutadiene melt under compression to move to larger q values as expected but to decrease significantly in intensity. Simulations reveal that this behavior does not result from loss of structure in the polymer melt upon compression but rather from the generic effects of differences in the pressure depende...

2014 The ionic aggregates in bulk halato-telechelic polymers, a class of ion-containing polymers with well controlled molecular characteristics, have a high degree of local order, as shown by EXAFS spectroscopy. In zinc neutralized carboxy telechelic polybutadiene each cation is surrounded by an average of 6 oxygen neighbours as well as by a second shell of up to 5 zinc atoms at a distance of 3...

We model the arm of a star polymer as an anchored random walk in an array of fixed obstacles with the added assumption of an energetic cost associated with the walk retracing its previous step. By including this energetic penalty for such “hairpin” turns on the chain, we are able to account for the thermorheological complexity of long-branched hydrogenated polybutadiene yet not introduce deviat...

Molecular dynamics simulations of a melt of freely rotating chains of 1,4-polybutadiene (FRC-PBD) have been performed over a wide range of temperature. Removal of the dihedral barriers in FRC-PBD allows for complete resolution of the Johari-Goldstein beta process from the primary alpha process in the simulation time window. We find that relaxation in the beta regime occurs as the result of larg...

Mooney viscosity is one of the important quality properties of polybutadiene rubber (PBR). It is important to implement appropriate measures to maintain and guarantee a uniform product quality required by the rubber processing industries. One major step towards quality assurance is the on line quality prediction of the product from the process parameters. This can be accomplished by developing ...