  Polymers and rod-like colloids (PaRC) adopt a favorable orientation under
sufficiently strong flows. However, how the flow kinematics affect the
alignment of such nanostructures according to their extensibility remains
unclear. By analysing the shear- and extension-induced alignment of chemically
and structurally different PaRC, we show that extensibility is a key
determinant of the structural response to the imposed kinematics. We propose a
unified description of the effectiveness of extensional flow, compared to
shearing flow, at aligning PaRC of different extensibility.
