US Patent 7592410 Polyethylene resin with narrow particle size distribution

The present invention relates to a polyethylene resin comprising A) a first ethylene homo- or copolymer fraction, and B) a second ethylene homo- or copolymer fraction, wherein fraction (A) has a lower molecular weight than fraction (B), characterized in that the polymer resin powder obtained directly after the final polymerisation step has a particle size distribution PSD95/5 equal to or smaller than 12. Furthermore, the invention relates to a process for the production of a polymer composition comprising: (i) a step in which ethylene monomers, and optionally further alpha-olefin-comonomers, are polymerised in liquid phase in the presence of a polymerisation catalyst, (ii) a step in which ethylene monomers, and optionally further alpha-olefin comonomers, are polymerised in the gas phase in the presence of a polymerisation catalyst, and (iii) obtaining a polymer resin powder after the final polymerisation step wherein the powder has a particle size distribution PSD95/5 equal to or smaller than 12.