A method for preparing ultrafine powders based on polymaiden, ultrafine polyamide powders, as well as their use

摘要

A method for preparing ultrafine powders based on polyamides, in which polyamides with a relative solution viscosity eta φ re φ l in the range of 1,5 to 2,0, measured in 0,5% - strength m - cresol solution at 25 deg c, under the action of pressure and / or temperature for generating an at least partial solution with an alcoholic medium in the presence of inorganic particles in contact, and then the polyamide from the at least partial solution precipitating, characterized in that a suspension of the inorganic particles suspended in an alcoholic medium starts. The resulting ultrafine polyamide powders have a specific surface area according to bet in the range of 5 - 100 m · 2 · / g; a fineness d φ 50 φ of less than 70 mu m; a bulk density sd in the range from 250 to 1000 g / l and a particle content of from 0,1 to 80 w -% of inorganic particles, based on the total weight of the polyamide. They are equally suitable for coatings as well as for the form of - and components with improved mechanical properties.