Preparation of polyolefin

A method for forming resin particles, comprising:

• forming a catalyst compound comprising hafnium;
• mixing the catalyst compound with an activator to form a catalyst complex;
• and
• combining the catalyst complex with a silica support to form a supported polymerization catalyst, wherein the supported polymerization catalyst has a productivity of at least about 7000 g polymer per g catalyst;
• reacting the supported polymerization catalyst with at least ethylene in a polymerization reactor to form resin particles, wherein the resin particles have:
• an average polymer particle size of at least about 0.660 mm;
• a size distribution of at least about 20% greater than 1 mm in diameter;
• and
• a ratio of fluidized bulk density to settled bulk density (FBD/SBD) of at least about 0.570.