Polymer is thought to be constructing a random structure in molten state. Especially, longer the longest relaxation time, polymer is in a relaxed state with lost the orientation history. Moreover, the amorphous polymer, cooled and solidified from such molten stage is thought to have no structural morphology and show stable mechanical property. However, we had investigated mechanical properties of virgin and recycled polystyrene and found that the mechanical properties of the recycled sample were much better than the virgin sample. Moreover, we had found that with increasing the holding time (longer than the longest relaxation time) in a compression molding, the mechanical properties of polystyrene increased so much. These results suggest that 1.The recycled polymer retains its molding history in its inner structure even if it is remolded at a high molten temperature and longer than the longest relaxation time. 2. The amorphous polymer has a possibility to construct an ordered structure in molten state longer than the longest relaxation time. In this study, we have measured the time dependence of shear stress at very slow shear rate region in the molten state. And we found that the shear stress grows even after the longest relaxation time.