Abstract: The copolymerization of ethylene and butadiene with a supported titanium catalyst is described.It is found that in this catalyst system ethylene is more reactive than butadiene.Although the catalytic efficiency of copolymerization is lower than that of homopolymerizations,it can still be maintained at a good level.The copolymerization products were extracted successively with a series of solvents and characterized by means of IRspectra,13CNMRspectra,X-ray diffraction analysis,differential thermal analysis and electron micrograph.The IRstudy showed that the butadiene units are substantially in trans-1,4 configuration.The ¹³CNMRstudy showed a PE/PBblock-type structure.The DTAand X-ray diffraction analysis showed that two crystalline phases exist in the products.The systematic solvent extraction and the TEMstudy showed that the solubility and the morphological structure of the copolymerization products are quite different from that of the blend of two homopolymers.The ethylene-butadiene copolymerization products can be chemically graphed with some polar monomers such as MMAand Maleic anhydride.It was found that the presence of a low content of unsaturated units ( 5 mol% ) greatly promote the capability of graft polymerization,which offers a possibility for modifying the properties of polymer.