Abstract: The present invention relates to a process for the preparation of polyamide-12 powder by anionic polymerization of lauryllactam in solution in a solvent of the lactam, the polyamide-12 powder being insoluble in this solvent, the polymerization being carried out: in the presence of a catalyst and of an activator; in the presence of a finely divided organic or inorganic filler, the proportion of this filler being less than or equal to 1.5 g per 1000 g of lauryllactam; and in the presence of an amide of formula R1—NH—CO—R2 in which R1 can be replaced by an R3—CO—NH— or R3—O— radical and in which R1, R2 and R3 denote an aryl, alkyl or cycloalkyl radical, the proportion of this compound being between 0.001 mol and 0.030 mol per 1000 g of lauryllactam.

Abstract: The present invention relates to a process for the preparation of polyamide-12 powder by anionic polymerization of lauryllactam in solution in a solvent of the said lactam, the polyamide-12 powder being insoluble in this solvent, the said polymerization being carried out: in the presence of a catalyst and of an activator; in the presence of a finely divided organic or inorganic filler, the proportion of this filler being less than or equal to 1.5 g per 1000 g of lauryllactam; and in the presence of an amide of formula R1—NH—CO—R2 in which R1 can be replaced by an R3—CO—NH— or R3—O— radical and in which R1, R2 and R3 denote an aryl, alkyl or cycloalkyl radical, the proportion of this compound being between 0.001 mol and 0.030 mol per 1000 g of lauryllactam.