Method for producing an intrinsically foamed polyamide and a shaped article therefrom

An intrinsically foamed polyamide comprising

• (a) 10 wt % to 80 wt % of a polyamide having a viscosity number in between 90 ml/g to 350 ml/g determined according to ISO 307;
• (b) 0.1 wt % to 10 wt % of a copolymer having a weight average molecular weight in between 5000 g/mol to 15000 g/mol, wherein said copolymer is obtained by reacting a mixture comprising (b1) maleic acid and/or maleic anhydride, and (b2) a vinyl monomer, wherein the molar ratio of (b1) to (b2) is in between 1:1 to 5:1;
• and
• (c) 20 wt % to 70 wt % of a reinforcing agent selected from metal fiber, metalized synthetic fiber, glass fiber, carbon fiber, ceramic fiber, mineral fiber, basalt fiber, inorganic fiber, kenaf fiber, jute fiber, flax fiber, hemp fiber, cellulosic fiber, sisal fiber and coir fiber,
• wherein the intrinsically foamed polyamide has a void fraction in between 1% to 60% determined from scanning electron microscopy and a foam density of less than 1500 kg/m3 determined according to ISO 1183/A.