A butene-1 polymer having: a) a Melt Flow Rate value of from 20 to less than 100 g/10 min., measured according to ISO 1133 at 190° C. with a load of 2.16 kg; b) an intrinsic viscosity (IV) measured in tetrahydronaphthalene (THN) at 135° C. equal to lower than 0.95 dl/g; c) a Mw/Mn value equal to or lower than 3.5 and a lower limit of 1.5; d) a Mz value of 180,000 g/mol or higher; and e) optionally, a comonomer content of up to 10% by weight.