Method for recycling filtering facepiece respirators

A method for recycling respiratory protection masks containing from 98.5% to 99.5% by weight of a predominant thermoplastic polymer chosen from polypropylene, polyethylene terephthalate, polylactic acid, homopolymers and copolymers of polyamide 6 (PA6) and aliphatic polyamides having an average number of carbons per each nitrogen atom of greater than 8.5, and from 0.05% to 1.5% of PVDF in the form of nanofibers, said method comprising a step of grinding the masks leading to the obtaining of flakes, and a step of granulating said flakes, leading to the obtaining of a masterbatch in the form of granules.