The adhesion between two immiscible polymers stitched together via mobile chains is studied with large scale molecular simulations employing a coarse-grained bead-spring model. An adhesion model is presented that incorporates both connector molecular slipping out viscously and bulk dissipation in two dissimilar glassy polymers, in which one is dense melt and another is loose. The contributions to the separation work from thermodynamics and chain suction are studied in dependence of the connector length, at constant temperature, and at fixed basic molecular parameters. It is shown that connector length relative to its entanglement length can enhance the adhesion toughness and interfacial strength. Bulk dissipation is not considerable with low connector areal density in mushroom regime, while becomes more evident in the loose melt with increasing connector length when the coverage density is increased up to overlapping brush regime. The results provide insight into the structure evolution of adhesion interface with mobile promoter molecular, which are useful for future developments of continuum cohesive models for fracture of polymer polymer interfaces. (C) 2013 Elsevier Ltd. All rights reserved.