High crystallinity polyamide foam particles and foam moldings

A process for preparing polyamide foam particles, comprising the steps of:

• a) Providing a polymer mixture comprising:
• (A) from 25 to 95 wt.-% of at least one polyamide;
• (B) from 5 to 75 wt.-% of at least one copolyamide prepared by polymerizing the following components:
• (B1) from 15 to 84 wt.-% of at least one lactam;
• and
• (B2) from 16 to 85 wt.-% of monomer mixture (M) comprising;
• (M1) at least one C32-C40 dimer acid;
• and
• (M2) at least one C4-C12 diamine;
• wherein the sum of the components (B1) and (B2) are 100 wt.-%;
• b) melting the polymer mixture and adding 0 to 5 wt.-%, based on 100% of the polymer mixture, of a nucleating agent before or after melting;
• c) impregnating the melted polymer mixture with 0.1 to 4.0 wt.-% carbon dioxide, nitrogen or mixtures thereof, based on 100% of the polymer mixture, to form an impregnated polymer melt;
• and
• d) extruding and granulating the impregnated polymer melt in an underwater pelletizer to form polyamide foam particles.