The immobolization technology and the selection of carrier of homogeneous Zeigler-Natta and metallocene catalysts were introduced. The major factors of carrier selection depend on strength

density

total pore volume

pore distribution

pore size

particle size and shape

and other physical properties of the carrier. The structure and performance characteristics of silica gel as polyolefin catalysts support were also reviewed

and the synthesis mechanism and influence factors in the process of silica gel preparation were introduced in details. The silica gel prepared have typical properties with specific surface area ranged from 280 m

2

/g to 320m

2

/g

bulk density 0.28-0.32g/cm

3

porosity volume 1.40-1.70 cm

3

/g and average pore diameter 18-22 nm. Research on silica gel with different properties (such as smaller particle size and modified silica gel

etc.) for special requirements of catalysts was proposed.