Powder containing a plastic except PVC, is formed by spraying a viscous material in a spray unit, to form melt droplets, and then cooling

摘要

A process for producing a powder containing a plastic comprises producing a viscous starting material (20) in at least one extruder (10), spraying the material in an in-line spray unit (11) to form melt droplets, and then cooling the droplets in an in-line cooling unit (12) to form powder particles with no surface adhesion. A process for producing a powder containing a plastic, especially a PVC free plastic, comprises producing a viscous starting material (20) in at least one extruder (10), spraying the material in an in-line spray unit (11) to form melt droplets, and then cooling the droplets in an in-line cooling unit (12) to form powder particles with no surface adhesion. The spray gas is sprayed through a nozzle and consists of air, a noble gas e.g. argon or helium, or nitrogen. The gas is passed into the spray unit at increased temperature, e.g. 200-300[deg]C. The starting material consists of at least one thermoplastic elastomer and/or a thermoplaste except PVC. The arrangement used to carry out the process includes a gas supply unit (27).