Process for producing a polyamide powder by precipitation

A process for producing a polyamide powder (PP) comprising at least one semicrystalline polyamide (P) and at least one additive (A) selected from the group consisting of inorganic pigments and stabilizers, comprising the steps of

• a) compounding the at least one semicrystalline polyamide (P) and the at least one additive (A) in an extruder to obtain a compounded mixture (cM) comprising the at least one semicrystalline polyamide (P) and the at least one additive (A),
• b) extruding the compounded mixture (cM) obtained in step a) from the extruder to obtain an extruded mixture (eM) comprising the at least one semicrystalline polyamide (P) and the at least one additive (A),
• c) introducing the extruded mixture (eM) obtained in step b) into a solvent (SV) to obtain a first suspension (S1) comprising the extruded mixture (eM) and the solvent (SV), wherein the solvent (SV) comprises lactam and water,
• d) heating the first suspension (S1) obtained in step c) to a first temperature (T1) wherein the at least one semicrystalline polyamide (P) present in the extruded mixture (eM) dissolves in the solvent (SV) to obtain a mixture (G) comprising the at least one semicrystalline polyamide (P) dissolved in the solvent (SV) and the at least one additive (A),
• e) cooling the mixture (G) obtained in step d) to a second temperature (T2) wherein the at least one semicrystalline polyamide (P) crystallizes to obtain a second suspension (S2) comprising the polyamide powder (PP) suspended in the solvent (SV), and
• f) separating the polyamide powder (PP) from the second suspension (S2) obtained in step e).