| 摘要 |
The invention relates to a process for the preparation of porous polyolefin particles, which process comprises the following steps: 1) dissolution of at least one crystallizable polyolefin in a solvent, which results in a solution being formed which comprises 0.1-50 wt. % polyolefin, and the initial polyolefin solution formed containing between 5 ppm and 20 wt. % of nucleating agent, 2) dispersion of the resulting polyolefin solution in a non-solvent, at a temperature that is higher than the crystallization temperature of the polyolefin in the polyolefin solution, upon which a multiphase system is formed, 3) cooling of the multiphase system, with simultaneous stirring, the cooling rate being between 0.05 and 10 DEG C./min, down to a temperature which is below the crystallization temperature of the polyolefin in the polyolefin solution, so that strong, polyolefin-containing particles are formed, 4) separation of the polyolefin-containing particles from the liquid(s), 5) drying of the polyolefin-containing particles at a temperature that is below the crystallization temperature of the polyolefin in the initial polyolefin solution. |
