Polyolefin composition obtained from recycled polyolefin

Abstract

The present disclosure relates to polyolefin compositions, in particular polypropylene compositions, containing (a) recycled polypropylene, (b) recycled polyethylene, (c) polyolefin elastomer (POE) and (d) a specific polypropylene heterophasic composition, useful in injection molded articles. The polyolefin compositions according to the present disclosure can be applied in the automotive field and in household goods such as suitcases and containers.

Description

Technical Field

[0001] This disclosure relates to polyolefin compositions, particularly polypropylene compositions, containing recycled polypropylene suitable for use in injection-molded articles. The polyolefin compositions according to this disclosure can be used in the automotive industry and in household products such as suitcases and containers. Background Technology

[0002] WO2006 / 067023 describes polyolefin compositions for this purpose, particularly suitcases, made of the following substances:

[0003] 50 to 77%, preferably 50 to less than 70%, of crystalline propylene polymer, wherein the amount of isotactic pentaunits (mmmm) is greater than 97.5 mol%, the fraction insoluble in xylene at 25°C is measured by 13C-MNR, and the polydispersity index is in the range of 4 to 10, preferably 5 to 10, more preferably 5.5 to 10.

[0004] 13 to 28%, preferably higher than 15 to 28%, of an elastomeric copolymer of ethylene and propylene, the copolymer having an amount of repeating units derived from ethylene in the range of 30 to 70%, preferably 35 to 60%, and being partially soluble in xylene at ambient temperature, the polymer fraction soluble in xylene at ambient temperature having an intrinsic viscosity value in the range of 2 to 4 dl / g; and

[0005] 10 to 22%, preferably 10 to 20%, of polyethylene having an intrinsic viscosity value in the range of 1 to 3 dl / g and optionally containing at most less than 10% of repeating units derived from propylene.

[0006] The above composition has good stiffness, impact resistance and resistance to stress whitening.

[0007] Generally speaking, while polyolefin compositions are appreciated for their performance, they are of concern regarding sustainability, especially given that their production is based on the use of non-renewable resources.

[0008] Therefore, a common attempt to alleviate this problem is to use variable recycled polyolefins, such as polypropylene or polyethylene, in multi-component polyolefin compositions.

[0009] Recycled polyolefins are derived from post-consumer waste (PCW) material streams, which are separated from other polymers such as PVC, PET, or PS through various steps.

[0010] In polyolefin recycling, particularly when dealing with material streams from post-consumer waste (PCW), one of the key issues is the difficulty in quantitatively separating polypropylene (PP) from polyethylene (PE) and vice versa. Therefore, despite being called recycled PE (rPE) or recycled PP (rPP), commercially available products from PCW sources have been found to be mixtures of PP and PE, with minor components reaching at most <50 wt%.

[0011] This fact is related to the presence of additives and minor components in recycled materials that may not be entirely suitable for the applications in which they are assumed to be used. This can lead to deterioration in the mechanical, optical, and aesthetic properties of such recycled PP / PE blends during remolding, as well as poor compatibility between the major polymer phases. Consequently, articles using r-PP or r-PE are considered to have lower reliability due to the inferior performance of the compositions derived from them.

[0012] Therefore, the use of recycled materials is strongly discouraged in applications requiring high performance levels and is limited to low-cost and less demanding applications.

[0013] It has now been unexpectedly discovered that certain formulations based on recycled polypropylene can be used to prepare injection molded products with an excellent combination of mechanical and aesthetic properties. Summary of the Invention

[0014] Therefore, the object of this disclosure is a polypropylene composition comprising (by weight percentage):

[0015] (a) 52 to 80%, preferably 55 to 75%, more preferably 58 to 70% of recycled polypropylene (r-PP);

[0016] (b) 8 to 30 wt% recycled polyethylene;

[0017] (c) 4 to 20%, preferably 5 to 18%, more preferably 6 to 15% of polyolefin elastomer (POE);

[0018] (d) 3 to 12%, preferably 4 to 10%, more preferably 5 to 8% of the composition, which contains

[0019] i) 20% to 90% crystalline polypropylene component, containing 25% to 75% melt flow rate (MFR). I Fractional Al of 0.5 to 10 g / 10 min and melt flow rate (MFR) of 75% to 25%. II MFR II / MFR IFraction A2 with a ratio of 30 to 2000; and wherein fractions A1 and A2 are independently selected from the group consisting of propylene homopolymers, propylene random copolymers containing up to 8% ethylene, and propylene random copolymers containing up to 8% of at least one C4-C10 α-olefin; and

[0020] ii) 10% to 80% ethylene and at least one C3-C 10 The copolymer component of the α-olefin contains 10 to 70% ethylene and optionally a small amount of diene, the copolymer being soluble in xylene at room temperature and having an intrinsic viscosity [η] of 4 to 9 dl / g;

[0021] The melt flow rate (ISO 1133 230°C / 2.16 kg) of the entire composition is in the range of 8.0 g / 10' to 30.0 g / 10', preferably 10.0 to 25.0 g / 10', more preferably 12.0 to 20.0 g / 10'; the percentages in (a), (b), (c) and (d) refer to the total weight of the polypropylene composition. Detailed Implementation

[0022] As used herein, the term "copolymer" refers to polymers having two different repeating units in the chain and polymers having more than two different repeating units, such as terpolymers. "Ambient temperature" and "room temperature" refer to a temperature of 25°C.

[0023] The term "crystalline polypropylene" in this application refers to a propylene polymer with an isotactic pentamematic unit (mmmm) content greater than 70 mol%, the amount of which isotactic pentamematic unit (mmmm) is determined by... 13 C-MNR measures fractions that are insoluble in xylene at 25°C; "elastomer" polymers are polymers with a solubility in xylene of more than 50 wt% at ambient temperature.

[0024] The characteristics of the components forming the polypropylene composition are not inextricably linked together. This means that a certain degree of preference for a particular characteristic does not necessarily involve a similar degree of preference for the remaining characteristics of the same or different components. Rather, it is intended in this disclosure that the characteristics of any component (a) to (d) and any preferred range of components (a) to (d) can be combined with any preferred range of one or more characteristics of components (a) to (d) and with any possible additional components and their characteristics described in this disclosure.

[0025] The r-PP component (a) comprises plastic waste from post-industrial or post-consumer sources. Preferably, it originates from post-consumer waste (PCW) PP packaging waste, such as detergent and shampoo bottles, dairy cans, and meat trays. The PP raw material waste can be pre-sorted by a waste management company. A suitable source of PP can be, for example, waste collected according to DSD324 (05-2012) and DSD324-1 standards (02-2016). Optical sorting can also be used to remove unwanted polymers, but some polystyrene or polyethylene (PE) contamination in the feed will still occur, preventing its use as the sole polymer component of the composition.

[0026] PP has three different product lines: PP homopolymer (PPh), PP random copolymer (PPr), and PP impact copolymer (or multiphase PP copolymer, PPc).

[0027] The waste can be characterized, for example, as originating from (a) extruded sheet and film materials, primarily homopolymers of PP (PPh) and random copolymers of PP (PPr), which are virtually rubber-free (e.g., biaxially oriented polypropylene (BOPP)); and (b) injection-molded materials, which are mixtures of homopolymers of PP (PPh), random copolymers of PP (PPr), and impact copolymers (PPc), containing approximately 15 wt% rubber.

[0028] The recycled PP component (a) may contain approximately half packaging material (BOPP) and half rubber-containing injection molding material. This injection molding material may contain rubber, such as C2-C3 rubber, thermoplastic elastomer (TPE), ethylene propylene diene monomer (EPDM), or ethylene propylene rubber (EPR).

[0029] The resulting mixture of recycled PP itself used as component (a) in the polymer composition may, for example, have a rubber content of 1.5 to 12 wt% (rubber from rubber-containing injection molding material; where wt% is the total amount of the mixture relative to the recycled PP). The recycled PP (a) of the polymer composition preferably consists of 25 to 75 wt% BOPP and 25 to 75 wt% rubber-containing injection molding material; where wt% is the total amount of recycled PP.

[0030] The amount of recycled PP in the polypropylene composition is preferably 55% to 75%, more preferably 58% to 70%; wherein wt% is relative to the total weight of the polypropylene composition.

[0031] Although the melt flow rate of recycled PP (ISO 1133 230°C / 2.16kg) is not important, it can generally be in the range of 5 to 150 g / 10', preferably in the range of 8 to 120 g / 10', and more preferably in the range of 40 to 100 g / 10'.

[0032] Polymer component (b) comprises recycled PE (rPE), which in turn comprises PE waste collected from various sources, such as PE bottles, PE containers with a volume of 5 liters or more and cleaned in accordance with environmental regulations, or PE extrusion tubes. The recycled PE preferably contains at least 90 wt%, more preferably at least 92 wt%, and most preferably at least 95 wt% recycled high-density polyethylene (HDPE).

[0033] The recycled PE tank contains various contaminants, which are removed through multiple steps, including cleaning, washing, and sorting. The recycled PE may preferably contain 0 to 6 wt%, more preferably 1 to 5 wt%, and most preferably 3 to 4.5 wt% of polypropylene and up to 1 wt% of polystyrene contaminants, where wt% is relative to the total amount of recycled PE.

[0034] Recycled PE preferably has a content of about 0.94 to 0.97 g / cm³. 3 Density within the range.

[0035] The MFR (2.16 kg, 190°C) of recycled PE is preferably in the range of 0.1 to 5 g / 10', more preferably in the range of 0.1 to 0.5 g / 10', and it is suitable for blow molding materials. In a specific embodiment, the recycled PE may preferably have an MFR of 0.4 to 0.9, more preferably 0.45 to 0.85, at 2.16 kg, 230°C (g / 10 min).

[0036] Recycled PE is preferably present in the polymer composition at 10 to 25 wt%, more preferably 15 to 23 wt%, wherein the wt% is relative to the total weight of the polypropylene composition.

[0037] Component (c) contains a polyolefin elastomer (POE), which is an ethylene-α-olefin copolymer. Examples of POE are C2-C4 copolymers, C2-C6 copolymers, and C2-C8 copolymers.

[0038] POE may preferably be a C2-C6 copolymer or a C2-C8 copolymer, having 70 to 80 wt% ethylene, more preferably 73 to 78 wt%, and most preferably 74 to 77 wt% ethylene; wherein wt% ethylene is relative to POE.

[0039] The POE used in this disclosure preferably comprises an ethylene (C2)octene (C8) elastomer obtained by using a catalyst based on a single active center transition metal compound.

[0040] The density of POE is preferably between 0.85 and 0.89 g / cm³. 3 More preferably, it is between 0.855 and 0.885 g / cm³. 3The optimal value is between 0.86 and 0.875 g / cm³. 3 between.

[0041] The POE preferably has an MFR (190°C, 2.16 kg) of 0.3 to 1, more preferably 0.4 to 0.7, and most preferably 0.45 to 0.6.

[0042] POE is commercially available. Examples of POE are Infuse 9107, Infuse 9077, and Engage XLT8677, which are commercially available from Dow Chemical Company.

[0043] POE is present at 4 to 20%, preferably 5 to 18%, more preferably 5 to 8%, relative to the total weight of the polypropylene composition.

[0044] Component (d) of the composition contains at least two components: a crystalline polypropylene component and a copolymer component. The crystalline polypropylene component (i) is present in an amount ranging from 20% to 90%, preferably 30% to 80%, and most preferably 50% to 80% of the total weight of the masterbatch composition. Conversely, the copolymer component (ii) is present in an amount ranging from 80% to 10%, preferably 70% to 20%, and most preferably 50% to 20% of the total weight of the masterbatch composition, wherein the sum of the percentage amounts of the components equals 100%.

[0045] The fractions A1 and A2 forming the crystalline polypropylene component (i) can each be a propylene homopolymer, a propylene random copolymer containing up to 8%, preferably 0.2% to 5% ethylene, or containing up to 8%, preferably 1% to 8% of at least one C4-C of the formula CH2=CHR. l0 A random copolymer of α-olefins with propylene, wherein R is a straight-chain or branched alkyl C1-C8 group or an aryl group, such as a phenyl group. An exemplary C4-C... l0 α-olefins include 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, and 1-octene, with 1-butene being particularly preferred.

[0046] Fractions A1 and A2 differ from each other in terms of their average molecular weight, as described by their melt flow rates. Fraction A1 has a relatively high molecular weight (low melt flow rate MFRI of 0.5 to 10 g / 10 min), while fraction A2 has a relatively low molecular weight (high melt flow rate). This relationship is expressed by the ratio MFR. II / MFR I The value is defined to be in the range of 30 to 2000, preferably 40 to 2000, more preferably 50 to 1000, and even more preferably 60 to 500.

[0047] Typically, fractions A1 and A2 contain at least 80% by weight of the polymer that is insoluble in xylene at room temperature, more preferably at least 85% by weight, and most preferably at least 90% by weight. For propylene homopolymers, based on the weight of a single fraction, the content of the polymer that is insoluble in xylene at room temperature is at least 90% by weight, more preferably at least 95% by weight, and most preferably at least 97% by weight.

[0048] Component (ii) is a C3-C compound containing 10 to 70% ethylene and at least one having the formula CH2=CHR. 10 A copolymer component of α-olefin and optionally a small amount of diene, wherein R is a straight-chain or branched C. l -C8 alkyl or aryl, such as phenyl. The ethylene content of the copolymer component is preferably 15 to 60%, most preferably 15 to 50%.

[0049] Exemplary C3-C 10 α-Olefins include propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, and 1-octene, with propylene and 1-butene being particularly preferred. Suitable dienes include butadiene, 1,4-hexadiene, 1,5-hexadiene, and ethylene-norbornene-1. When present, the amount of diene is typically 0.5 to 10% by weight relative to the copolymer component (ii).

[0050] The copolymer component (ii) is soluble in xylene at room temperature and has an intrinsic viscosity [n] of 4 to 9, preferably 5 to 8, and most preferably 5.5 to 7 dl / g in tetrahydronaphthalene at 135°C.

[0051] The melt flow rate of the entire component (d) can be in the range of 0.1 to 40 g / 10 min, more preferably 0.3 to 15 g / 10 min, and even more preferably 0.5 to 10 g / 10 min.

[0052] Component (d) can be prepared by mechanically blending components (i) and (ii) or by sequential polymerization steps as described, for example, in US 6,586,531B2 (the relevant portion of which is incorporated herein by reference).

[0053] Optionally, inorganic fillers are present as an additional component (e). Suitable fillers may be selected from the group consisting of talc, glass fiber, CaCO3, clay, carbon black, and mica. Talc is preferred. Talc may be unmodified and preferably without surface coating or treatment. Talc can increase the stiffness and strength of polymer compositions and the articles produced. Preferably, it has a very small particle size, with an average size of less than 5 μm.

[0054] The filler may be wholly or partially derived from fillers present in the recycled components of the composition and / or added as fresh filler during the preparation of the polypropylene composition.

[0055] Typically, based on the total weight of the polypropylene composition, component (e) is preferably present in an amount ranging from 2 to 4 wt%.

[0056] SEBS rubber can be used as an optional component (f).

[0057] SEBS rubber is a (partially) hydrogenated styrene-butadiene-styrene block copolymer. They belong to the styrene-based block copolymer (SBC) family. These polymers are triblock copolymers, with styrene at both ends of the polymer chain containing internal polybutadiene, polyisoprene, or hydrogenated polybutadiene or polyisoprene blocks.

[0058] SEBS copolymers are commercially available, for example under the trade names of Kraton and Tuftec, such as Kraton SEBSG1657MS.

[0059] If used, SEBS is present in 0.1 to 4 wt%, preferably 0.2 to 3 wt%, based on the total weight of the polypropylene composition.

[0060] The polypropylene composition may further contain 0.05 to 10 wt%, preferably 0.1 to 8 wt%, of additives.

[0061] Additives may include polyethylene (e.g., virgin HDPE or recycled HDPE), maleic anhydride-grafted PE (PEMA), maleic anhydride-grafted PP (PPMA), stabilizers, peroxides, calcium oxide (CaO), or colorants and release agents.

[0062] Examples of PE are high-density PE (HDPE), low-density PE (LDPE), and linear low-density PE (LLDPE).

[0063] PP-compatible acids with polar groups, such as PPMA, can be added.

[0064] PEMA, PE, or PPMA can be added to the polymer composition, for example, at 0.1 to 2 wt%, preferably 0.2 to 1 wt%, more preferably 0.4 to 0.8 wt%.

[0065] Stabilizers can be added, such as masterbatch like TosafME 833848, which is a blend of about 70 wt% LDPE with phenolic stabilizers (Irganox B225) and Irgafos. Typically, such masterbatch is added in an amount of 0.2 to 1.5 wt%, preferably 0.3 to 1.2 wt%.

[0066] Peroxides can be added in the form of organic compounds or masterbatches. Peroxides improve the flow of materials and can be used to achieve the desired melt flow.

[0067] The peroxide can be selected, for example, from the group consisting of Zebraflow T028, Zebraflow T0214, or Zebraflow T0318, which are masterbatches of peroxides and polyolefins. The specific amount of peroxide is determined by those skilled in the art based on the melt flow rate of the individual components, their respective amounts, and the final desired melt flow rate. For example, the peroxide can account for 2 to 10 wt% of the entire additive package.

[0068] CaO can be added to suppress the release of HCl. CaO can also be added as a masterbatch along with, for example, LDPE. CaO can be added, for example, in the range of 0 to 2 wt%.

[0069] The black colorant can be added to the polymer composition, for example, in the form of a masterbatch blend, at a rate of 0.1 to 5 wt%, preferably 1 to 2 wt%.

[0070] Stripping agents are compounds used to remove volatiles during the processing of a composition. BYK4200 is one such commercially available product.

[0071] Based on the total amount of the polypropylene composition, the amount of additive in the whole package is in the range of 0.5 to 7% wt, preferably 1 to 6% wt.

[0072] In a preferred embodiment of this disclosure, the polypropylene composition comprises the following components (by weight percentage):

[0073] (a) 52 to 80%, preferably 55 to 75%, more preferably 58 to 70% of recycled polypropylene (r-PP);

[0074] (b) 8 to 30 wt% recycled polyethylene;

[0075] (c) 4 to 20%, preferably 5 to 18%, more preferably 6 to 15% of polyolefin elastomer (POE);

[0076] (d) 3 to 12%, preferably 4 to 10%, more preferably 5 to 8% of the composition, which contains

[0077] i) 20% to 90% crystalline polypropylene component, containing 25% to 75% melt flow rate (MFR). I Fractional Al of 0.5 to 10 g / 10 min and melt flow rate (MFR) of 75% to 25%. II MFR II / MFR IFraction A2 with a ratio of 30 to 2000; and wherein fractions A1 and A2 are independently selected from propylene homopolymers, propylene random copolymers containing up to 8% ethylene, and at least one C4-C polymer containing up to 8% ethylene. 10 The group consisting of random copolymers of propylene and α-olefins; and

[0078] ii) 10% to 80% ethylene and at least one C3-C 10 The copolymer component of the α-olefin contains 10 to 70% ethylene and optionally a small amount of diene, the copolymer being soluble in xylene at room temperature and having an intrinsic viscosity [η] of 4 to 9 dl / g;

[0079] -0.05 to 10 wt%, preferably 0.1 to 8 wt% of additives,

[0080] The melt flow rate (ISO 1133 230°C / 2.16 kg) of the entire composition is in the range of 8.0 g / 10' to 30 g / 10', preferably 10 to 25 g / 10', more preferably 12 to 20 g / 10'; (a), (b), (c), (d) and the percentage of additives refer to the total weight of the polypropylene composition.

[0081] The polymer composition according to this disclosure preferably has a flexural modulus in the range of 800 to 1400 MPa, more preferably 810 to 1300 MPa.

[0082] The polymer composition preferably has a strength of 50 to 100 kJ / m³ at 23°C. 2 More preferably 40 to 80 kJ / m 2 The Charpy impact strength ranges from 5 to 20 kJ / m at -20°C. 2 More preferably, it is within the range of 6 to 15 kJ / m 2 between.

[0083] The compositions disclosed herein can exhibit a yield tensile strength equal to or greater than 15 MPa, a yield elongation equal to or greater than 10%, and a tensile strength at break equal to or greater than 10 MPa.

[0084] The compositions disclosed herein can be obtained by mechanically blending components (a) to (d) and optionally other components and additives using conventional techniques.

[0085] The polymer composition can be prepared using a co-rotating twin-screw tandem extruder, to which components (a to d) and optional other components and additives are added.

[0086] Additives can be added to the recycling extruder (first extruder) and the compounding extruder (second extruder) of a tandem extruder.

[0087] Polypropylene polymer compositions can be present in granule or flake form for use in the manufacture of articles.

[0088] The polypropylene polymer composition of this disclosure, made from recycled PP, is suitable for manufacturing long-term use products such as boxes, trays, suitcases, or consumer products.

[0089] Articles made from polymer compositions are preferably formed by injection molding or blow molding.

[0090] The following examples are given for illustrative purposes and not for limiting this disclosure.

[0091] Example

[0092] Characterization

[0093] Xylene-soluble (XS) fraction at 25°C

[0094] 2.5 g of polymer and 250 ml of xylene were introduced into a glass flask equipped with a refrigerator and a magnetic stirrer. The temperature was raised to the boiling point of the solvent over 30 minutes. The resulting clear solution was then refluxed and stirred for 30 minutes. The sealed flask was then placed in an ice-water bath for 30 minutes, followed by a constant-temperature water bath at 25°C for 30 minutes. The resulting solid was filtered through rapid filter paper. 100 ml of the filtrate was poured into a pre-weighed aluminum container and heated on a hot plate under a nitrogen stream to remove the solvent by evaporation. The container was then kept under vacuum in an oven at 80°C until constant weight was achieved. The weight percentage of the polymer soluble in xylene at room temperature was then calculated.

[0095] The content of xylene soluble fraction is expressed as a percentage of the original 2.5 g, and then expressed as the percentage of xylene insoluble fraction (%) by the difference (rounded up to 100%).

[0096] The XS values ​​for components B) and C) have been calculated using the following formula:

[0097] XStot=WaXSA+WbXSB+WcXSC

[0098] Where Wa, Wb, and Wc are the relative amounts of components A, B, and C, respectively, and (A+B+C=1).

[0099] Melt flow rate (MFR)

[0100] Unless otherwise specified, measurements shall be taken at 230°C and a load of 2.16 kg in accordance with ISO 1133.

[0101] Intrinsic viscosity (IV)

[0102] The sample was dissolved in tetrahydronaphthalene at 135°C and then poured into a capillary viscometer. The viscometer tube (Ubbelohde type) was surrounded by a cylindrical glass jacket; this setup allowed for temperature control using a circulating thermostatic liquid. The downward movement of the meniscus was timed by a photoelectric device.

[0103] The meniscus is passed in front of the upper lamp by a counter with a quartz crystal oscillator. The counter is stopped when the meniscus passes the lower lamp, and the outflow time is recorded: this is converted to an intrinsic viscosity value using the Huggins equation (Huggins, ML, *Journal of the American Chemical Society*, 1942, 64, 2716), provided that the flow time of the pure solvent is known under the same experimental conditions (same viscometer and same temperature). [η] is determined using a single polymer solution.

[0104] Multi-dispersion index:

[0105] Measurements were taken at 200°C using an RMS-800 parallel plate rheometer sold by RHEOMETRICS (USA), operating at oscillation frequencies increasing from 0.1 radians / second to 100 radians / second. Based on the cross modulus, PI can be derived using the following formula:

[0106] PI = 10⁵ / Gc

[0107] Where Gc is the cross modulus, which is defined as the value (in Pa) when G' = G”, where G' is the storage modulus and G” is the loss modulus.

[0108] Ethylene (C2) content

[0109] propylene / ethylene copolymer 13 C NMR

[0110] 13 C10 NMR spectra were acquired on a Bruker AV-600 spectrometer equipped with a cryoprobe, which was operated at 160.91 MHz in Fourier transform mode at 120 °C.

[0111] S ββThe carbon peak (nominalized according to "Monomer Sequence Distribution in Ethylene-Propylene Rubber Measured by 13C NMR. 3. Use of Reaction Probability Mode" CJ Carman, RA Harrington, and CE Wilkes, Macromolecules, 1977, 10, 536) was used as an internal reference at 29.9 ppm. The sample was dissolved in 1,1,2,2-tetrachloroethane-d2 at 8% wt / v at 120 °C. Each spectrum was acquired using a 90° pulse, with a 15-second delay between pulses and CPD to remove 1H-13C coupling. 512 transients were stored at 32 K data points using a 9000 Hz spectral window.

[0112] According to Kakugo (“Carbon-13 NMR determination of monomer sequence distribution in ethylene-propylene copolymers prepared with δ-titanium trichloride-diethylaluminum chloride”, M. Kakugo, Y. Naito, K. Mizunuma and T. Miyatake, Macromolecules 1982, 15, 1150), the following equation was used to specify the spectra, evaluate the ternary distribution and composition:

[0113] PPP = 100T ββ / S PPE=100T βδ / S EPE=100T δδ / S

[0114] PEP = 100S ββ / S PEE=100S βδ / S EEE=100(0.25S γδ +0.5S δδ ) / S

[0115] S = T ββ +T βδ +T δδ +S ββ +S βδ +0.25Sγδ +0.5S δδ

[0116] The molar percentage of ethylene content is evaluated using the following equation:

[0117] E%mol = 100 * [PEP + PEE + EEE] The following equation is used to evaluate the weight percentage of ethylene content:

[0118]

[0119] Where P%mol is the molar percentage of propylene content, and MW E and MW P These are the molecular weights of ethylene and propylene, respectively.

[0120] The product of reaction rates, r1r2, is calculated according to Carman (CJ, Wilkes, Macromolecules, 1977; 10, 536):

[0121]

[0122] The stereoregularity of the propylene sequence is determined by PPP mmT ββ (28.90 to 29.65 ppm) and full T ββ The ratio of (29.80 to 28.37 ppm) is calculated as mm content.

[0123] The ethylene C2 content of component b2 was measured by measuring the C2 content of component B), and then calculated using the formula C2tot = Xb1C2b1 + Xb2C2b2, where Xb1 and Xb2 are the amounts of components b1 and b2 in the composition.

[0124] Samples for mechanical testing

[0125] Samples were obtained according to ISO 1873-2:2007.

[0126] The Charpy impact test is determined according to ISO 179-1eA and ISO 1873-2.

[0127] Yield elongation: Measured according to ISO 527.

[0128] Elongation at break: Measured according to ISO 527.

[0129] Fracture stress: Measured according to ISO 527.

[0130] Tensile modulus according to ISO 527-2.

[0131] Melting point and crystallization point

[0132] The melting point of samples weighing 5 to 7 mg was measured using a DSC instrument conforming to ISO 11357-3 at a scan rate of 20 °C / min, under cooling and heating conditions and in an inert N2 flow. Indium was used for instrument calibration.

[0133] Example

[0134] The production and evaluation of extruded and injection molded products shall comply with ISO 19069-2:2016, ISO 294-1:2017 and ISO 294-3:2002.

[0135] Material

[0136] Recycled PP

[0137] Recycled PE

[0138] The POE component (c) used is Infuse 9077.

[0139] Component (d) is a composition prepared according to Example 4 of US US6,586,531B2.

[0140] 0.75 wt% TOSAF was used as a stabilizer.

[0141] The additives contain a mixture of conventional stabilizers (Irgafos 168 / Irganox 1010), ZebraFlow T028 as a peroxide, and BYK4200 as a stripping agent.

[0142] In Comparative Example 1, the same composition as in Example 1 was used, except that component (d) was not used.

[0143] Table 1: Polymer composition of recycled PP (%wt)

[0144]

[0145] Table 2 – Properties of the final composition

[0146] The above data indicate that the compositions of this disclosure, based on a large amount of recycled materials, provide an improved impact / stiffness balance superior to compositions of the prior art.

Claims

1. A polypropylene composition comprising (in weight percent): (a) 52 to 80% of recycled polypropylene; (b) 8 to 30 wt% of recycled polyethylene; (c) 4 to 20% of a polyolefin elastomer (POE); (d) 3 to 12% of a composition comprising i) 20% to 90% crystalline polypropylene component containing 25% to 75% melt flow rate (MFR) measured according to ISO 1133 at 230°C and 2.16 kg load. I The fractional Al was 0.5 to 10 g / 10 min, and the melt flow rate (MFR) was 75% to 25% as measured according to ISO 1133 at 230 °C and a load of 2.16 kg. II MFR II / MFR I Fraction A2 with a ratio of 30 to 2000; and wherein fractions A1 and A2 are independently selected from propylene homopolymers, propylene random copolymers containing up to 8% ethylene, and at least one C4-C polymer containing up to 8% ethylene. 10 The group consisting of random copolymers of propylene and α-olefins; and ii) 10 to 80 % of ethylene and at least one C3-C12 10 a copolymer component of α-olefins, the copolymer containing 10 to 70 % of ethylene and optionally small amounts of dienes, the copolymer being soluble in xylene at room temperature and having an intrinsic viscosity [η] of 5.5 to 7 dl / g; The melt flow rate value of the whole composition, measured according to ISO 1133 at 230 °C and under a load of 2.16 kg, is in the range of 8.0 g / 10' to 30.0 g / 10'; the percentages of (a), (b), (c) and (d) are referred to the total weight of the polypropylene composition and said polymeric composition has a Charpy impact strength at 23 °C in the range of 50 to 100 kJ / m 2 .

2. The polypropylene composition according to claim 1, wherein: the weight range of component (a) is 55 to 75%; the weight range of component (b) is 10 to 25%; the weight range of component (c) is 5 to 18%; the weight range of component (d) is 4 to 10%.

3. The polypropylene composition according to claim 1, having a melt flow rate in the range of 10 to 25 g / 10 min measured according to ISO 1133 at 230°C and a load of 2.16 kg.

4. The polypropylene composition according to claim 1, wherein the recycled polyethylene component (b) has a density in the range of 0.94 to 0.97 g / cm3and is present in an amount of 10 to 25 wt% of the total weight of the polypropylene composition. 3 range of 0.94 to 0.97 g / cm3and is present in an amount of 10 to 25 wt% of the total weight of the polypropylene composition.

5. The polypropylene composition according to claim 1, wherein component (c) is an ethylene-a-olefin copolymer selected from C2-C4 copolymers, C2-C6 copolymers and C2-C8 copolymers, wherein the amount of ethylene is in the range of 70 to 80% wt.

6. The polypropylene composition according to claim 1, wherein component (c) has a density in the range of 0.85 to 0.89 and a melt flow rate in the range of 0.3 to 1 g / 10’ measured according to ISO 1133-1 at 190°C and a load of 2.16 kg.

7. The polypropylene composition according to claim 1, wherein in the component (d) 30 to 80% of component (i) is contained and the MFR of fractions Al and A2 thereof is such that the ratio MFR II / MFR I is in the range of 40 to 2000.

8. The polypropylene composition according to claim 1, wherein 20 to 70% of component (ii) is contained in the component (d).

9. The polypropylene composition according to claim 1, wherein the component (ii) has an ethylene content in the range of 15 to 60 weight%.

10. The polypropylene composition according to claim 1, wherein the melt flow rate of the entire component (d) is in the range of 0.3 to 15 g / 10 min.

11. The polypropylene composition according to claim 1, wherein the component (d) is present in an amount in the range of 4 to 10 weight% of the total polypropylene composition.

12. The polypropylene composition according to claim 1, comprising SEBS rubber as component (f) in an amount of 0.1 to 4% wt, based on the total weight of the polypropylene composition.

13. The polypropylene composition according to claim 1, comprising an additive package.

14. The polypropylene composition according to claim 1, having a tensile strength at yield equal to or higher than 15 MPa, a tensile elongation at yield equal to or higher than 10%, and a tensile strength at break equal to or higher than 10 MPa.

15. An injection molded article made from the composition according to claim 1.

Images