Propylene terpolymer

A terpolymer composition comprising:

• A) From 80 wt % to 97 wt %;
• of a first propylene, ethylene, 1-butene terpolymer having:
• i) the content of ethylene derived units ranging from 0.5 wt % to 3.2 wt %, based upon the total weight of the first terpolymer;
• ii) the content of 1-butene derived units ranging from 7.2 wt % to 14.8 wt % based upon the total weight of the first terpolymer;
• iii) the xylene soluble fraction at 25° C. ranging from 7.2 wt % to 13.4 wt %, based upon the total weight of the first terpolymer;
• iv) the melting point determined by differential scanning calorimetry (DSC), according to ISO 11357-3, with a heating rate of 20° C./minute ranging from 123° C. to 138° C.;
• v) the C13 NMR sequences EEE ranging from 0.16 mol % to 0.40 mol %;
• and
• vi) the melt flow rate, MFR, measured according to ISO 1133 at 230° C. with a load of 2.16 kg, ranging from 1.0 g/10 min to 20.0 g/10 min;
• and
• B) From 20 wt % to 3 wt %;
• of a second propylene, ethylene, 1-butene terpolymer having:
• i) the content of ethylene derived units ranging from 0.5 wt % to 3.2 wt %, based upon the total weight of the second terpolymer;
• ii) the content of 1-butene derived units ranging from 14.4 wt % to 26.5 wt % based upon the total weight of the second terpolymer;
• and
• iii) the xylene soluble fraction at 25° C. ranging from 38.2 wt % to 60.2 wt % based upon the total weight of the second terpolymer;
• wherein the content of 1-butene derived units of component A) is lower than the amount of the content of 1-butene derived units of component B);
• and
• the terpolymer composition having -the melt flow rate, MFR, measured according to ISO 1133 at 230° C. with a load of 2.16 kg, ranging from 3.0 g/10 min to 20.0 g/10 min;
• the sum of the amounts of A) and B) being 100 wt %.