Polyolefin resin powder suitable for selective laser sintering and its preparation method

A method for preparing a polyolefin resin powder, comprising:

• a) heating and dissolving a polyolefin resin in an organic solvent having a solubility parameter less than or equal to a solubility parameter of the polyolefin resin to obtain a polyolefin resin solution;
• b) cooling the polyolefin resin solution to cause precipitation of a solid, thereby obtaining a solid-liquid mixture;
• c) optionally adding an adjuvant to the solid-liquid mixture;
• and
• d) conducting solid-liquid separation and drying the separated solid to obtain a polyolefin resin powder,
• wherein a difference between the solubility parameter of the organic solvent and the solubility parameter of the polyolefin resin is within 0-20% of the solubility parameter of the polyolefin resin,
• wherein, in the polyolefin resin solution, an amount of the organic solvent is 600-1200 parts by weight, based on an amount of 100 parts by weight of the polyolefin resin,
• wherein, in step b), the polyolefin resin solution is cooled to a target temperature via one or more intermediate temperatures and held for 30-90 minutes at each of said one or more intermediate temperatures,
• wherein the one or more intermediate temperatures are in the range of 40-100° C., and
• wherein the polyolefin resin powder obtained from step d) contains particles that are spherical or spheroidal particles having a particle size of 25-150 μm, and a particle size distribution D10=43-69 μm, D50=61-103 μm, and D90=85-138 μm.