To obtain ethylene/tetrafluoroethylene(ETFE) (co)polymers and ethylene/chlorotrifluoroethylene(ECTFE) (co)polymers exhibiting high softness which cannot be attained by the use of a plasticizer.

A composition comprises a polymer mixture A of polymers composed of (a) 10-70 mole % of ethylene (E), (b) 30-90 mole % of a fluorinated monomer selected among tetrafluoroethylene(TFE), chlorotrifluoroethylene(CTFE) and a mixture thereof, and (c) 0.1-30 mole %, based on the total amount of monomers (a) and (b), of an acrylic monomer, where the polymer mixture A contains polymer fractions having different acrylic comonomer contents and the modulus of the polymer mixture A at 23°C (ASTM D1708) is lower than at least 10% of the modulus of a polymer composed of monomers (a), (b) and (c), the polymer fraction having substantially the same acrylic comonomer content.