Superior C2C3C4 terpolymer based cast film and C2C3C4 terpolymer

Cast film made from an ethylene-propylene-1-butene terpolymer, wherein the ethylene-propylene-1-butene terpolymer includes

• a) units derived from ethylene in an amount of 0.2 to 1.2 mol-% with respect to a total terpolymer;
• and
• b) units derived from propylene in an amount of 93.6 to 95.3 mol-% with respect to the total terpolymer;
• and
• c) units derived from 1-butene in an amount of 4.5 to 5.2 mol-% with respect to the total terpolymer,
• d) wherein the units derived from ethylene, propylene and 1-butene add up to 100 mol-% and
• e) a total amount of units derived from ethylene and 1-butene of 4.8 to 6.5 mol-%, and
• f) 2,1 regioinversions in an amount of 0.36 to 0.55 mol-% as determined by 13C-NMR analysis;
• and
• g) a melt flow rate MFR2 (230° C./2.16 kg) measured according to ISO 1133 in a range from 10 to 14.5 g/10 min, and
• h) a melting temperature Tm measured by differential scanning calorimetry (DSC) following the equation
• Tm
• ≥
• [
• 150
• -
• 1.6
• *
• (
• defects
• )
• -
• 0.12
• *
• (
• defects
• )
• 2
• ]
• ⁢
• °
• ⁢
• C
• ,
• wherein defects denote a sum of units derived from ethylene, units derived from 1-butene and 2,1 regioinversions, all values in mol-%,
• wherein the film has a sealing initiation temperature (SIT) (as determined by a method described in the experimental part) below 112° C.