Slip of a polymer as it flows through a conduit has been modeled by applying the concept of junctions at the conduit/polymer interface as well as in the bulk of the polymer fluid. This model has been combined with a kinetic equation describing a reaction, to which activation rate theory applies, between bonded and free macromolecules at the interface. The result is a prediction of the temperature dependence of wall slip velocities. The prediction was found to be consistent with published data for an ethylene‐propylene copolymer. It was also found that at constant temperature a power‐law relation provides a good description of the dependence of wall slip velocity on wall shear stress.