Free-flowing, thermoplastically processible and post-crosslinkable polyurethane powders

A process for production of free-flowing polyurethane powders comprising:

• a) producing a non-aqueous emulsion of fine droplets of a first component, stabilized by a surface-active compound, wherein said first component is selected from the group consisting of IA) a component having free NCO groups and IB) a component IB having groups reactive towards NCO groups,
• b) reacting said emulsion with a second component reactive with said first component, said second component selected from the group consisting of IIA) a component having an average of two hydrogen atoms reactive towards NCO groups per molecule and IIB) a component having an average of two NCO groups per molecule, with the proviso that if the emulsion of step a) is based upon component IA), then said second component is IIA) and if the emulsion of step a) is based upon component IB), then said second component is IIB), wherein step b) is conducted in the presence of a separately produced component III that contains at least partially blocked isocyanate groups, and in the presence of an inert organic liquid carrier phase in which the components IA or IB and the respective reaction product are insoluble, and
• c) separating the reaction product from said inert organic carrier.