Using nonequilibrium Brownian dynamics computer simulations, we have investigated the steadystate statistics of a polymer chain under three different shear environments: (i) linear shear flow inthe bulk (no interfaces), (ii) shear vorticity normal to the adsorbing interface, and (iii) shear gradientnormal to the adsorbing interface. The statistical distribution of the chain end-to-end distance and itsorientational angles are calculated within our computer simulations. Over a wide range of shearrates, this distribution can be mapped onto a simple theoretical finite-extensible-nonlinear-elasticdumbbell model with fitted anisotropic effective spring constants. The tails of the angulardistribution functions are consistent with scaling predictions borrowed from the bulk dumbbellmodel. Finally, the frequency of the characteristic periodic tumbling motion has been investigatedby simulation as well and was found to be sublinear with the shear rate for the three setups, whichextends earlier results done in experiments and simulations for free and tethered polymer moleculeswithout adsorption.
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