PROPYLENE COPOLYMER Russian patent published in 2023 - IPC C08F210/06 C08F210/08 C08F2/18 C08F2/34 C08F4/6592 C08J5/18 C08L23/14 C08L23/18 

FIELD: copolymers.

SUBSTANCE: present invention is related to a multimodal random copolymer of propylene and butene suitable for film formation, having a melt flow rate (MFR₂) from 2.5 to 16.0 g/10 min and a butene content from 2.0 to 7.0 wt.%, while the flexural modulus of the specified copolymer ranges from 850 MPa to 1600 MPa, the specified copolymer is obtained using a metallocene catalyst and the specified copolymer contains: (i) from 40 to 60 wt.% fraction (A) of propylene and butene having MFR₂ from 0.5 to 10.0 g/10 min and a butene content from 0.5 to 10.0 wt.%, and (ii) from 60 to 40 wt.% fraction (B) of propylene and butene, having MFR₂ from 0.5 to 10.0 g/10 min and a butene content from 1.0 to less than 6.0 wt.%, while fractions (A) and (B) are different. The invention is also related to a method for producing the above-mentioned multimodal random copolymer of propylene and butene, to a film made from it, and to its use for the manufacture of film.

EFFECT: technical result is production of a new material suitable for use as packaging, in particular a film, which combines very good mechanical properties in terms of rigidity, measured by tensile modulus, with attractive sealing properties, for example in terms of low sealing temperature, and good sterilization behaviour in terms of maintaining low turbidity after sterilization and strength.

11 cl, 3 tbl