POLYMER COMPOSITION SUITABLE FOR MAKING FILMS BY EXTRUSION BLOWING Russian patent published in 2025 - IPC C08J5/18 C08L23/14 C08K3/01 B65D1/00 

FIELD: chemistry.

SUBSTANCE: group of inventions relates to a blown film containing a polymer composition, and a flexible packaging system selected from bags or pouches for food and pharmaceutical packaging, including such a blown film. Film produced by extrusion blowing contains a polymer composition consisting of: A) from 70.0 wt.% to 95.0 wt.% in terms of total weight of polymer composition C₂C₃ random copolymer, wherein said C₂C₃ random copolymer has a melting point of 110 °C to 140 °C, determined by differential scanning calorimetry according to ISO 11357-3, melt flow index MFR₂ at 230°C, 2.16 kg, determined according to ISO 1133, from 0.5 g to 4.0 g/10 min, and total content of C2 from 1 wt.% to 10 wt.% based on total weight of C₂C₃ random copolymer, B) from 5.0 wt.% to 30.0 wt.% of LDPE in terms of total weight of polymer composition; wherein said LDPE has density, determined according to ISO 1183, from 915 kg/m³ to 922 kg/m³ and MFR₂ at 190 °C, 2.16 kg, determined according to ISO 1133, from 0.9 g to 20.0 g/10 min, and optionally C) additives, provided that the weight fractions of components (A) and (B) and additives, if present, total 100 wt.%. Described also is a flexible packaging system selected from bags or bags for food and pharmaceutical packaging, including a blown film.

EFFECT: providing the film produced by extrusion blowing, having improved optical properties, especially low turbidity, and at the same time demonstrating good mechanical and sealing properties.

12 cl, 4 tbl, 3 ex