The chemical states of titanium of TiCl4·donor

and MgCl2-supported Ziegler-Natta catalysts obtained by milling method and precipitation method

and the interactions between TiCl4

donor

and MgCl2 were studied by XPS and IR methods

and the electron binding energies of Ti2p3 in TiCl4·Mgcl2

TiCl4·donor and TiCl4·MgCl2·donor and the characteristic adsorption peaks of C＝O bond or c—O—c bend in MgCL2·donor

TiCL4·donor and TiCL4·MgCL2·donor were compared．The results showed that the oxidation states of titanium species in Ziegler-Nana catalysts using different compounds

such as benzoate

phthalate

1

3-diether as internal electron donors weRE different．The internal donor did not react directly on titanium

but transfered electron to titanium through MgcL2 as medium

and inereased the electron-cloud density of Ti species

and thus decreased the oxidation state and electron binding energy of Ti species．