Segment confinement is constructed by the coordination effect between copper(Ⅱ) and poly-(ethylene oxide).The crystallization and melting behaviors of PEO under segment confinement are studied.Broadband dielectric spectroscopy(BDS) is used to characterize the relaxation behaviors of PEO under confinement.The characteristic relaxation time of and process of PEO is found to be increased with copper(Ⅱ) contents

which indicates the cooperative motion of PEO segments and twisting motion of main chain are frustrated.The relaxation time obtained from BDS provides a quantitative evaluation of confinement degree.DSC results show a significant increase of glass transition temperature of PEO with increasing copper(Ⅱ) contents and cold crystallization is observed

which indicates the coordination effect of copper(Ⅱ) has actually restricted the segment motion of PEO.Meanwhile

the crystallinity and melting temperature of PEO decrease with the increase of copper(Ⅱ) contents.WAXD shows that copper(Ⅱ) bromide does not crystallize in the blends.No crystal modification of PEO is observed.AFM shows that in all thin films of PEO/CuBr2 blends

PEO forms extended chain crystals(IF(0)) and the lamella thickness of PEO does not change with copper(Ⅱ) contents.However

much more screw dislocations are observed as the copper(Ⅱ) content increases

which indicates a large number of defects are formed in the PEO crystals.Similar with the situation of metal material

the defects should be responsible for the melting point depression.