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A new method to investigate the evolution of chain entanglement of ultrahigh molecular weight polyethylene(UHMWPE)in dilute solution blends was reported.The systems prepared from blending polyethylene wax and UHMWPE.Component one had a molecular weight(Mw=1000 g/mol)slightly less than the critical entanglement molecular weight(Me=4ρRT/5GN).Component two had an ultrahigh molecular weight(Mw =4500 000 g/mol).The fraction of component two was 2.5 wt%.Such a blend was referred as the dilute solution blend.The evolvement of chain entanglement during annealing was monitored by rheology.The morphology of the crystallized blends after different stage of annealing was investigated through scanning electron microscope,differential scanning calorimeter,small angle X-ray scattering and rheology,respectively.It was showed that the blends would transfer from heterogeneous melt to homogenous melt with the increasing of annealing time.The entanglement density first decreased and then increased to thermodynamic stable state upon annealing.Finally,the mechanism for the transition of melts was discussed.