HIGH MELT FLOW POLYPROPYLENE COMPOSITION Russian patent published in 2025 - IPC C08L23/12 

FIELD: chemistry.

SUBSTANCE: group of inventions relates to a polypropylene composition with high melt fluidity, which includes mixtures based on mixed plastics with polypropylene. Described is a composition suitable for making articles, obtained by mixing at least components (A), (B) and (C) at the following ratio of components: (A) from 25 wt.% to 75 wt.% of a mixture of mixed plastics with polypropylene, which is produced from wastes after consumption and/or industrial wastes; (B) from 17 wt.% to 65 wt.% of a first propylene homopolymer; and (C) from 3 wt.% to 30 wt.% of a second propylene homopolymer, all percentages being relative to the total amount of the composition. Mixture (A) of mixed plastics with polypropylene has: content of crystalline fraction (CF), determined according to CRYSTEX QC analysis data, in range from 82.5 to 96.0 wt. %, and content of soluble fraction (SF) determined by CRYSTEX QC analysis data in range of 4.0 to 17.5 wt.%, wherein said crystalline fraction (CF) has an ethylene content (C2(CF)), determined by FTIR spectroscopy, calibrated by quantitative ¹³C-NMR spectroscopy, in range of 1.0 to 12.5 wt.%; and said soluble fraction (SF) has an intrinsic viscosity (IV(SF)) in range of 0.9 to below 2.5 dl/g; first propylene homopolymer (B) has: melt flow index MFR₂ (230 °C, 2.16 kg, ISO 1133) from 500 to 1,100 g/10 min; and second propylene homopolymer (C) has melt flow index MFR₂ (230 °C, 2.16 kg, ISO 1133) from 80 to 200 g/10 min; and modulus of elasticity in tension from 1,500 to 2,100 MPa, and composition has melt flow index MFR₂ (230 °C, 2.16 kg, ISO 1133) from 50 to 100 g/10 min. An article containing the composition and use of the composition for making articles are also described.

EFFECT: providing a composition based on polypropylene and mixed plastics obtained from secondary used polyolefin streams, characterized by a balance of properties with respect to impact properties and especially mechanical properties, such as tensile properties and fluidity, which is manifested in high melt flow index.

16 cl, 4 tbl, 7 ex