DEFORMATION, ORIENTATION, AND SCATTERING FROM POLYMER-CHAINS IN SHEAR-FLOW - A BROWNIAN DYNAMICS SIMULATION STUDY

The conformation of polymer chains in shear flow is simulated by applying the Brownian dynamics technique to bead-and-spring model chains without and with hydrodynamic interaction (HI). The deformation of the chain is characterized as the variation of the components of the square radius of gyration tensor with shear rate. Our simulation results for the increase in the radius of gyration agree with early results without HI and confirm recent renormalization group predictions with HI. Available experimental data from neutron scattering are discussed in terms of these theoretical and simulation results. We predict the scattering intensities for a simulated experiment in which the orientation of the scattering vector with respect to the flow direction is continuously varied. We also consider the deformation and orientation of subchains in the polymer, looking at the stretching and orientation of the individual springs in the model as functions of their position along the chain.