POLYPROPYLENE COMPOSITION FOR EXTERNAL APPLICATIONS IN CARS Russian patent published in 2025 - IPC C08L23/12 C08L23/16 C08K3/34 

FIELD: chemistry.

SUBSTANCE: group of inventions relates to polypropylene compositions suitable, in particular, for external applications in cars, including mixed plastics, mixtures based on polypropylene and inorganic fillers. Composition suitable for use in automobiles is obtained by mixing at least components (A), (B), (C) and (D): (A) from 15 to 50 wt.% of a mixture of mixed plastics and polypropylene; (B) from 20 to 50 wt.% of a heterophasic propylene copolymer; (C) 5 to 25 wt.% ethylene-based plastomer and (D) 5 to 25 wt.% talc; wherein all percentages relate to the entire composition. Mixture (A) of mixed plastics and polypropylene has: content of the crystalline fraction (CF), determined according to the CRYSTEX QC analysis, in range of 85.0 to 96.0 wt.% and the content of the soluble fraction (SF), determined by CRYSTEX QC analysis, in range of 4.0 to 15.0 wt.%, wherein said crystalline fraction (CF) has ethylene content (C2(CF)), determined by infrared Fourier spectroscopy, calibrated by quantitative ¹³C-NMR spectroscopy, in range of 1.0 to 10.0 wt.%; and said soluble fraction (SF) has characteristic viscosity (IV(SF)) in range of 0.9 to 2.1 dl/g. Heterophasic propylene copolymer (B) comprises a matrix phase and an elastomeric phase dispersed therein and has a melt flow rate MFR₂ (230 °C, 2.16 kg, ISO 1133) from 85 to 250 g/10 min; content of soluble fraction (SF), determined from CRYSTEX QC analysis, in the range from more than 20.0 wt.% to 30.0 wt.%; and intrinsic viscosity IV (SF) of said soluble fraction, measured in decaline in accordance with DIN ISO 1628/1 at 135 °C, from 2.0 dl/g to 4.5 dl/g. Ethylene-based plastomer (C), which is a copolymer of ethylene with comonomer units selected from alpha-olefins having from 3 to 12 carbon atoms, has melt flow index MFR₂ (190 °C, 2.16 kg, ISO 1133) from 0.2 to 2.5 g/10 min and density from 850 to 870 kg/m³. Composition is characterized by a melt flow index MFR₂ (230 °C, 2.16 kg, ISO 1133) from 8 to 50 g/10 min. Automotive article and use of the composition for injection molding of automotive articles are also described.

EFFECT: providing a composition based on mixed plastics and polypropylene, originating from streams of used regenerated polyolefins with balance of impact properties, heat resistance, coloring and especially mechanical properties, such as tensile strength and fluidity, manifested in high melt flow rate, suitable for injection molding, especially in automotive industry, which can replace complex heterophase polypropylene copolymers.

14 cl, 5 tbl, 6 ex