A process for producing a polymer by polymerizing at least one fluorinated monomer in the presence of a radical initiator and a surfactant in a polymerization medium containing essentially only carbon dioxide. The surfactant is a functional (per)fluoropolyether having recurring units (R1) and at least one functional group containing a heteroatom other than fluorine, the recurring units containing at least one ether linkage in the main chain and at least one fluorine atom. Molded article containing the polymer obtained from the process.