COPOLYMERS OF PROPYLENE AND BUTENE 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 5.0 to 20.0 wt.%, while the flexural modulus of the specified copolymer ranges from 750 to 1600 MPa, the specified copolymer is obtained using a metallocene catalyst, and the specified copolymer contains: (i) from 30 to 55 wt.% a fraction of copolymer (A) of propylene and butene having MFR₂ of 0.5 to 10.0 g/10 min and a butene content of 2.0 to 10.0 wt.%, and (ii) from 70 to 45 wt.% fractions of copolymer (B) of propylene and butene, having MFR₂ from 0.5 to 10.0 g/10 min and butene content from 6.0 to 20.0 wt.%, and 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: production of a new material suitable for use as 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 behaviour during sterilization in terms of maintaining low levels of turbidity after sterilization and strength.

10 cl, 3 tbl