Prodn. of mono:dispersed thermoplastic fine powder - by feeding to extruder and grinding while controlling temp., cooling in vortex zone and re-grinding coarse particles

摘要

A process for producing a mono-dispersed thermoplastic powder, includes feeding the material to be ground into an extruder, advancing the material to a primary grinding stage, grinding the material and advancing it, until the material is a fine powder and the temp. is 60-150 deg.C. The powder is then cooled to 40-100 deg.C in an advancing and vortex zone. The remaining coarse components are ground in a secondary grinding stage. The temp. of the powder at the secondary grinding stage is 60-150 deg.C. The extruder speed is between 60 and 180 rpm. ADVANTAGE - The process is simple and economic