Preparation And Application Of Graphene Based Support For Ethylene Polymerization

In this thesis,graphene/SiO2 spherical nanocomposite as new kinds of support for Z-N catalyst was synthesized.Compared with methods directly using graphene nanosheet dispersions in solvent as the support,this has reduced 23%defect.The composites were characterized systematically by SEM,TEM,XRD,FT-IR,Raman and TG.The composites loading by Ziegler Natta catalyst were applied in the synthesis of ethylene.The main results were as follows:Graphene oxide(GO)dispersion was prepared by a modified Hummer's method,and the average thickness of GO is about 0.7nm.Shell-like graphene oxide particles has been prepared by spray drying while flower-like graphene oxide particles being prepared by spray freeze drying.Nano-SiO2 whose particle size ranged from 20nm to 70nm was prepared by Stober.A process of combining ultrasound induced self-assembly to preparation synthesized Sandwich structure and using spray freezes drying and thermal reduction to obtain RGO/SiO2.Bowl-like particles have been prepared by spray drying.Z-N catalyst was prepared with 5%wt Ti,Spherical GO and GO will fragmentation and agglomeration in the reaction,RGO-SiO2 was slightly damaged,the spherical porous structure maintenance.Spherical GO and GO increase defect after reacts with BuMgCl,an ordered arrangement of the graphene layers in the complexes are not destroyed severely after reacts with BuMgCl.UHMWPE/Graphene was prepared after polymerization reaction.Samples were gray powder,liquid,no lumps and spherical shape with an average grain size of 150?m,which is the carrier of size three times.