Uncompounded polyolefin powder which is multimodal and has a particle size distribution such that D95 is less than 355 μm, D5 is at least 60 μm, and (D90−D10)/D50 is less than 1.2, where D95, D90, D50 and D10 are defined such that 95 wt %, 90 wt %, 50 wt % and 10 wt % of the polymer particles have a diameter of less than D95, D90, D50 and D10 respectively.