The invention discloses a class of
fluorine-containing alpha-
diimine nickel coordination compounds for preparing a
polyolefin elastomer, and an intermediate thereof, wherein the coordination compoundhas a single catalytic activity center, the molecular weight of a
polymer can be regulated and controlled by changing a ligand structure and
polymerization conditions, and the coordination compound has the advantages of high catalytic activity, low cost, stable performance and the like. The invention further provides preparation methods of an asymmetric alpha-
diimine nickel coordination compound containing a difluoro group, and an intermediate thereof, wherein the two preparation methods have the advantages of mild
reaction conditions, short period, simple operation conditions and the like. The invention also provides uses of a
metal nickel coordination compound and a catalyst
system thereof, wherein the
metal nickel coordination compound is used for catalyzing
ethylene polymerization, shows good catalytic activity and obtains a
polyethylene elastomer material with narrow molecular
weight distribution. The obtained
polyethylene elastomer material is high in branching degree, has good tensile strength, elongation at break and elastic resilience, is a
thermoplastic elastomer material and has great industrial application potential.