A novel high performance MgCl

2

/TiCl

4

catalyst with tetrabutyloxsilicane as electron donor was prepared for ethylene slurry polymerization process. The properties of the catalyst such as particle size distribution

catalytic activity

hydrogen responsibility and copolymerization performance were investigated and compared with commercial catalyst (imported catalyst). Copolymerization of ethylene and 1-butylene using the catalyst was studied in a pilot plant. The composition

structure and property of the copolymer were characterized by

13

C nuclear magnetic resonance (

13

C NMR) and gel permeation chromatography-Infrared (GPC-IR)

and compared with those of the copolymer obtained from a commercial catalyst. In comparison with the commercial catalyst

the novel catalyst had a higher activity (up to 34.6 kg·g

-1

) and a better particle size distribution (PSD)

and produced polymers having higher bulk density (up to 0.37 g·cm

-3

) with less fine resin. Meanwhile

the novel catalyst showed a higher hydrogen responsibility and better copolymerization performance. The results indicated that the copolymer obtained from the novel catalyst has a higher branch in the high molecular weight fraction and lower branch in the low molecular weight fraction.