Polyolefins compositions obtained from recycled polyolefins

A tailored polypropylene composition using recycled polypropylene, homopolymers, and fillers addresses the separation and contamination issues, enabling high fluidity and performance in injection molded articles.

WO2025180846A1PCT designated stage Publication Date: 2025-09-04BASELL POLIOLEFINE ITALIA SRL
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Patent Information

Application Number
PCT/EP2025/053757
Authority / Receiving Office
WO · WO
Patent Type
Applications
Current Assignee / Owner
Priority Date
2024-03-01
Filing Date
2025-02-12
Publication Date
2025-09-04

AI Technical Summary

Technical Problem

The challenge lies in the difficulty of separating and utilizing recycled polypropylene (r-PP) and polyethylene (r-PE) from post-consumer waste streams due to their inherent mixtures and contamination with additives, leading to deteriorated mechanical, optical, and aesthetic properties in polyolefin compositions, particularly in applications requiring high fluidity and performance.

Method used

A specific formulation of recycled polypropylene (r-PP) with defined properties, combined with propylene homopolymers, ethylene copolymers, and inorganic fillers, achieves a high fluidity and excellent mechanical and aesthetic properties suitable for injection molded articles.

Benefits of technology

The formulation results in high fluidity injection molded articles with improved mechanical and aesthetic properties, suitable for demanding applications such as automotive and houseware, despite using recycled materials.

✦ Generated by Eureka AI based on patent content.

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Patent Text Reader

Abstract

A polypropylene composition comprising: (a) from 60.0 wt% to 85.0 wt% of a recycled polypropylene (r-PP) (b) from 10.0 wt% to 30.0 wt% of a composition comprising; b1) from 29 wt% to 59 wt%; of a propylene homopolymer; b2) from 41 wt% to 71 wt% %; of a propylene ethylene copolymer (c) from 0.5wt% to 6.0 wt%; of a propylene ethylene copolymer (d) from 1 to 6% by weight of an inorganic filler.
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Description

POLYOLEFINS COMPOSITIONS OBTAINED FROM RECYCLED POLYOLEFINSFIELD OF THE INVENTION

[0001] The present disclosure relates to polyolefin compositions, in particular polypropylene compositions containing recycled polypropylene that can be used in injection molded articles. The polyolefin compositions according to the present disclosure find application in automotive field, and houseware such as suitcase and containers.BACKGROUND OF THE INVENTION

[0002] Polyolefin compositions for this use, in particular suitcase, are described in W02006 / 067023 as being made of:50-77%, preferably 50 to less than 70%, of a crystalline propylene polymer having an amount of isotactic pentads (mmmm), measured by 13C-NMR on the fraction insoluble in xylene at 25°C, higher than 97.5 molar % and a poly dispersity index ranging from 4 to 10, preferably from 5 to 10, more preferably from 5.5 to 10;13-28%, preferably higher than 15 to 28%, of an elastomeric copolymer of ethylene and propylene, the copolymer having an amount of recurring units deriving from ethylene ranging from 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 ranging from 2 to 4 dl / g; and10-22%, preferably 10 to 20%, of polyethylene having an intrinsic viscosity value ranging from 1 to 3 dl / g and optionally containing recurring units deriving from propylene in amounts up to less than 10%.

[0003] The above mentioned compositions are endowed with good stiffness, impact resistance and stress-whitening resistance.

[0004] Generally speaking, polyolefin compositions, although being appreciated in terms of performances, give raise to concerns in terms of sustainability with particular reference to the fact that their production is based on the use of non-renewable sources.

[0005] As a result, a common attempt to mitigate the problem is that of using, in multicomponent polyolefin compositions, variable amounts of recycled polyolefins such as polypropylene or polyethylene.

[0006] The recycled polyolefin derive from streams of post-consumer waste (PCW) material that undergoes various step of separation from other polymers, such as PVC, PET or PS.

[0007] One of the key problems in polyolefin recycling, especially when dealing with material streams from post-consumer waste (PCW), is the difficulty to quantitatively separate polypropylene (PP) from polyethylene (PE) and vice-versa. Thus, although named recycled PE (rPE) or recycled PP (rPP), the commercially available products from PCW sources have been found to be mixtures of PP and PE, the minor component reaching up to <50 wt %.

[0008] This fact, associated to the presence in the recycled material of additives and minor components that may not be totally suitable for the application in which they are supposed to be used, leads to the consequence that such recycled PP / PE-blends may suffer from deteriorated mechanical, optical and aesthetic properties and poor compatibility between the main polymer phases during remolding. The result is a perceived lower reliability of articles coming from the use of r-PP or r-PE due to the lower performances of the compositions from which they derive.

[0009] As a consequence, the use of recycled material in applications requiring a high- performance level, is strongly discouraged and limited to low-cost and non-demanding applications.

[0010] The problem is still more difficult to be solved in situations where high fluidity polypropylene compositions are needed. Manufacture of objects of a larger size via injection molding in fact, often requires polymer grades with higher fluidity. However, polymer compositions with higher fluidity may involve an undesired degrading of mechanical properties which makes the final object non-compliant for certain applications.

[0011] It has now been unexpectedly found that certain specific formulations based on recycled polypropylene can be used in the preparation of high fluidity injection molded articles having an excellent combination of mechanical and aesthetic properties.SUMMARY OF THE INVENTION

[0012] It is therefore an object of the present disclosure a polypropylene composition comprising:(a) from 60.0 wt% to 85.0 wt%, preferably from 63.0 wt% to 80.0 wt %, more preferably from 66.0 wt% to 78.0 wt % of a recycled polypropylene (r-PP) wherein the recycled polypropylene composition (A) has : a propylene content, measured with13C-NMR, higher than 60 wt%, preferably higher than 65 wt%; more preferably ranging from 70 wt% to 95 wt%;Melt Flow Rate (ISO 1133 230°C / 2.16 kg) ranging from 35 to 74 g / lOmin; preferably ranging from 41 to 68 g / lOmin; more preferably ranging from 43 to 62 g / lOminTensile modulus, measured according to ISO 527-2, ranging from 620N / mm2to 1620 N / mm2; preferably ranging from 850 N / mm2to 1450 N / mm2; more preferably ranging from 950 N / mm2to 1350 N / mm2;Charpy impact test at 23°C, determined according to ISO 179- 1 eA, and ISO 1873-2, ranging from 2.2 KJ / m2to 12.0 KJ / m2; preferably ranging from 3.4 KJ / m2to 9.2 KJ / m2; more preferably ranging from 4.4 KJ / m2to 7.3 KJ / m2Elongation at break, measured according To ISO 527, ranging from 7 % to 37 %;preferably ranging from 9 % to 32 %; more preferably ranging from 12 % to 27 % the FTTR spectrum of film recorded as described in the example section shows at least two peaks at different wavenumbers (cm-1) selected from:3303 ±1 cm’1; 1726 ±1 cm ; 1642 ±1 cm4; 1600 ±1 cm4; 1550 ±1 cm4; 906 ±1 cm4; 839 ±1 cm4, 818 ±1 cm;748 ±1 cm4; 695 ±1 cm4;(b) from 10.0 wt% to 30.0 wt% preferably from 12.0 to 26.0 wt%, more preferably from 15.0wt% to 25.0 wt% of a composition comprising; bl) from 29 wt% to 59 wt%; preferably from 34 wt% to 54 wt%; more preferably from 39 wt% to 49 wt% of a propylene homopolymer having a xylene soluble lower than 4.0 wt%; preferably lower than 3.5 wt%; more preferably lower than 3.0 wt% and a melt flow rate (ISO 1133 230°C / 2.16 kg) ranging from 65 g / 10 min to 120 g / 10 min; preferably from 70 g / 10 min to 115 g / 10 min; more preferably from 75 g / 10 min to 110 g / 10 min; b2) from 41 wt% to 71 wt%; preferably from 46 wt% to 66 wt%; more preferably from 51 wt% to 61 wt%; of a propylene ethylene copolymer containing from 30.8 wt% to 62.0 wt%; preferably from 33.6 wt% to 59.6 wt%; more preferably from 38.7 wt% to 57.9 wt% of ethylene derived units measured according to13C-NMR method described in the specification; said composition being further characterized bya Melt Flow Rate (ISO 1133 230°C / 5.0 kg) ranging from 0.5 to 11.2 g / lOmin; preferably ranging from 0.9 to 10.1 g / lOmin, more preferably ranging from 1.5 to 8.5 g / lOmin; an amount of fraction soluble in xylene at 25°C ranging from 35.0 wt% to 58.0 wt%; preferably ranging from 38.0 wt% to 56.0 wt% ; more preferably ranging from 40 wt% to 53 wt%; intrinsic viscosity of the fraction soluble in xylene at 25°C, measured in tetrahydronaphthalene at 135 °C, ranging from 2.3 to 4.9 dl / g; preferably ranging from 2.6 to 4.5 dl / g, more preferably ranging from 2.9 to 4.1 dl / g, total content of ethylene, measured according to13C-NMR method described in the specification, ranging from 19.2 wt% to 35.9 wt%; preferably ranging from 22.4 wt% to 33.8 wt%; more preferably ranging from 23.6 wt% to 31.7 wt%;(c) from 0.5wt% to 6.0 wt%; preferably from 1.0 wt% to 5.0wt% more preferably from 1.5wt% to 4.5 wt% of a propylene ethylene copolymer composition comprising; i) fraction soluble in xylene at 25°C ranging from 20.0 wt% to 38.0 wt%; preferably from 22.0 wt% to 36.0 wt%; more preferably from 25.0 wt% to 33.0 wt%; ii) the melt flow rate (230°C / 2.16 kg.. ISO 1133) ranging from from 0.4 g / lOmin to 4.0 g / lOmin; preferably from 0.6 g / lOmin to 3.0 g / lOmin; more preferably from 1.0 g / lOmin to2.2 g / lOmin; iii) intrinsic viscosity, measured in tetralin, of the fraction soluble in xylene at 25°C ranging from 5.7 dl / g to 9.2 dl / g; preferably from 6.0 dl / g to 8.7 dl / g; more preferably from 6.2 dl / g to8.2 dl / g; said propylene-ethylene copolymer composition comprising: cl) from 27 wt% to 40 wt%; preferably from 29 wt% to 38 wt%; more preferably from 30 wt% to 36 wt% of a propylene homopolymer having a melt flow rate MFR1 (230°C / 2.16 kg. ISO 1133) ranging from 62.0 g / lOmin to 100.0 g / lOmin; preferably from 72 g / lOmin to 87 g / lOmin; more preferably from 76 g / lOmin to 84 g / 10min; c2) from 27 wt% to 40 wt%; preferably from 29 wt% to 38 wt%; more preferably from 30 wt% to 36 wt% of a propylene homopolymer having a melt flow rate MFR2 (230°C / 2.16 kg. ISO 1133) lower than MFR1 ; preferably lower than MFR1 -40 g / 10 min; more preferably lower than MFR1-65 g / 10 min;c3) from 20 wt% to 46 wt% preferably from 24 wt% to 42 wt%; more preferably from 28 wt% to 40 wt% of a propylene ethylene copolymer having a content of ethylene derived units ranging from 18.0 wt% to 48.0 wt%; preferably from 22 wt% to 44 wt%; more preferably from 27 wt% to 39 wt%;(d) from 0.5wt% to 6.0 wt%; preferably from 1.0 wt% to 5.0wt% more preferably from 1.5wt% to 4.5 wt% of an inorganic filler; the whole composition having a value of melt flow rate (ISO 1133 230°C / 2.16 kg) ranging from 5.0 g / lOmin to 40.1 g / 10 min preferably from 8.0 g / 10 min to 38.0 g / 10 min, more preferably from 12.0 g / 10 min to 33.0g / 10 min; the percentages of (a) to (d) being referred to the total weight of the polypropylene composition.BRIEF DESCRIPTION OF THE DRAWINGSFig 1 shows the FTIR spectrum of component a) used in the examples.DETAILED DESCRIPTION OF THE INVENTION

[0013] The term “copolymer” as used herein refers to both polymers with two different recurring units and polymers with more than two different recurring units, such as terpolymers, in the chain. By “ambient temperature” and “room temperature” is meant a temperature of 25 °C.

[0014] By the term “crystalline polypropylene” is meant in the present application a propylene polymer having an amount of isotactic pentads (mmmm), measured by13C-MNR on the fraction insoluble in xylene at 25° C, higher than 70 molar %; by “elastomeric” polymer is meant a polymer having solubility in xylene at ambient temperature higher than 50 wt%.

[0015] The features of the components forming the polypropylene composition are not inextricably linked to each other. This means that a certain level of preference of one the features should not necessarily involve the same level of preference of the remaining features of the same or different components. On the contrary, it is intended in the present disclosure that any component (a) to (d) and any preferred range of features of components(a) to (d) can be combined with any preferred range of one or more of the features of components (a) to (d) and with any possible additional component, and its features, described in the present disclosure.

[0016] The r-PP component (a) comprises plastic waste of post-industrial or post-consumer origin. Preferably, it origins from post-consumer waste (PCW) PP packaging waste, such as for example detergent and shampoo bottles, dairy pots and meat trays, etc. The PP raw material waste can be pre-sorted by waste management companies. One suitable PP source can for example be the waste material collected under the DSD324 (05-2012) and DSD324- 1 standard (02-2016). Optical sorting can also be used to remove unwanted polymers, but polystyrene or polyethylene (PE) contamination in the feed may still occur to a certain extent that prevent from using it as the only polymer component of the composition.

[0017] PP is available in three different families of products, PP homopolymers (PPh), PP random copolymer (PPr) and PP impact copolymer (or heterophasic PP copolymer, PPc).

[0018] The waste material can for example be characterized as originating from following sources (a) extrusion sheet and film material, mostly PP homopolymers (PPh) and PP random copolymers (PPr), virtually without rubber (such as for example biaxially-oriented polypropylene (BOPP)); and (b) injection molded material, which are a mix of PP homopolymer (PPh), PP random copolymers (PPr) and impact copolymer (PPc), containing about 15 wt% rubber.

[0019] The recycled PP component (a) can contain approximately half of packaging material (BOPP) and half of rubber-containing injection molded material. This injection molded material can contain rubbers, such as for example C2-C3 rubber, thermoplastic elastomers (TPE), ethylene propylene diene monomers (EPDM) or ethylene propylene rubber (EPR).

[0020] The resulting mix of the recycled PP itself used in the polymer composition as component (a) can for example have a rubber content of between 1.5-12 wt% (rubber from rubber-containing injection molded material; wherein wt% is relative to the total amount of the mix of the recycled PP).

[0021] The recycled PP (a) of the polypropylene composition is preferably made-up of between 25-75 wt% BOPP and between 25-75 wt% rubber-containing injection molded material; wherein wt% is relative to the total amount of recycled PP.

[0022] The recycled PP is present between preferably 60 to 80%, more preferably 62-75% within the polymer composition; wherein wt% is relative to the total weight of the polypropylene composition.

[0023] Component b) is an heterophasic propylene ethylene copolymer, for example it can be commercially available such as Hifax CA138A sold by Lyondellbasell.

[0024] Component c) is an heterophasic propylene ethylene copolymer, for example it can be commercially available such as Hifax X1956A sold by Lyondellbasell.

[0025] Component (d) is an inorganic filler. Suitable inorganic fillers can be chosen from the group consisting of talc, fiber glass, CaCCh, clays carbon black and mica. Among them talc is preferred. Talc can for example be unmodified and does preferably not have a surface coating or surface treatment. Preferably, it has very small particle size with average size lower than 5 pm.

[0026] In general, component (d) is comprised from 1 wt% to 6%wt more preferably present in amounts ranging from 2 to 4 wt%, based on the total weight of the polypropylene composition. The said amount can derive in total or in part from the filler present in recycled component of the composition and / or be added as a fresh filler in the preparation of the polypropylene composition.

[0027] As an optional component, a SEBS rubber can be used.

[0028] SEBS rubbers are (partly) hydrogenated styrene-butadiene-styrene block copolymers. They belong to the family of styrenic block copolymers (SBC). These polymers are triblock copolymers, having styrene at both extremities of the polymer chain with an internal polybutadiene, polyisoprene or hydrogenated polybutadiene or polyisoprene block.

[0029] SEBS copolymers are commercially available, for example under the tradenames of Kraton and Tuftec, such as for example Kraton SEBS G1657MS.

[0030] If used, the SEBS is present between 0.1-4 wt%, preferably between 0.2-3 wt%, based on the total weight of the polypropylene composition.

[0031] The polypropylene composition can further comprise between 0.05-10 wt%, preferably 0.1-8 wt%, of additives.

[0032] Additives may comprise polyethylenes (for example virgin HDPE or recycled HDPE), maleic anhydride grafted PEs (PEMA), maleic anhydride grafted PPs (PPMA), stabilizers, peroxides, calcium oxides (CaO) or colorants and stripping agents.

[0033] Examples of PE are High-Density PE (HDPE), Low-Density PE (LDPE) and Linear Low-Density PE (LLDPE).

[0034] A PP compatible acid having a polar group can be added, such as for example a PPMA.

[0035] A PEMA, PE or PPMA can for example be added to the polymer composition between 0.1-2 wt%, preferably between 0.2-1 wt%, more preferably between 0.4-0.8 wt%.

[0036] A stabilizer can be added, such as for example masterbatches like Tosaf ME 833848, which is a blend of about 70 wt% LDPE with a phenolic stabilizer (Irganox B225) and an Irgafos. Typically, such a masterbatch is added in an amount between 0.2 and 1.5 wt%, preferably between 0.3 and 1.2 wt%.

[0037] A peroxide, in the form of an organic compound or masterbatch can be added. The peroxide improves the flow of the material and can be used to achieve a desired melt flow.

[0038] The peroxide can for example be selected from the group of Zebraflow T028, Zebraflow T0214 or Zebraflow T0318, which are masterbatches of a peroxide with a polyolefin. The specific amount of peroxide is determined by the skilled in the art having in mind the melt flow rate of the single components, their respective amounts and the final desired melt flow rate. As an example, the peroxide can amount to 2-10 wt% of the entire additive package.

[0039] A CaO can be added to inhibit release of HC1. The CaO can be also added as a masterbatch with for example LDPE. CaO can for example be added in a range between 0- 2 wt%.

[0040] A black colorant can for example be added to the polymer composition between 0.1-5 wt%, preferably between 1-2 wt% in the form of a masterbatch blend.

[0041] Stripping agents are compounds used to remove volatiles during processing of the composition. BYK 4200 is one of the commercially available products.

[0042] In a preferred embodiment of the present disclosure, the polypropylene composition consists of the following components

[0043] The polypropylene composition according to the present disclosure preferably has a Tensile modulus ranging between 880-1800 MPa, preferably between 900-1600 MPa.

[0044] The polypropylene composition preferably has a Charpy impact strength at 23°C of 30-100 kJ / m2, more preferably between 40-80 kJ / m2The Charpy impact strength at -20°C ranges from 5 to 20 kJ / m2, more preferably between from 6 to 15 kJ / m2

[0045] The polypropylene composition of the present disclosure may exhibit a tensile strength at yield equal to or higher than 15 MPa, an elongation at yield equal to or higher than 10%, a tensile strength at break equal to or higher than 10 MPa.

[0046] The polypropylene composition of the present disclosure can be obtained by mechanical blending of the components (a)-(d) and optionally further components and additives according to conventional techniques.

[0047] The process of making the polymer composition may use a co-rotating twin screw tandem extruder to which the components (a-d) and optionally additives are added.

[0048] Additives can be added in a reclaim extruder (first extruder) and a compounding extruder (second extruder) of a tandem extruder.

[0049] The polypropylene polymer composition can be presented in granule or flake form to be used for manufacturing articles.

[0050] The polypropylene polymer composition of the present disclosure recycled PP is suitable for manufacturing products for long-term use, such as for example boxes, trays, suitcases or consumer goods.

[0051] The articles made from the polymer composition are preferably formed by injection molding or blow-molding.

[0052] The following examples are given in order to illustrate, but not limit the present disclosure.EXAMPLESCHARACTERIZATIONSXylene-soluble (XS) Fraction at 25 °C

[0053] 2.5 g of polymer and 250 ml of xylene are introduced in a glass flask equipped with a refrigerator and a magnetic stirrer. The temperature is raised in 30 minutes up to the boiling point of the solvent. The resulting clear solution is then kept under reflux and stirred for 30minutes. The closed flask is then kept for 30 minutes in a bath of ice and water, then in a thermostatic water bath at 25 °C for 30 minutes. The resulting solid is filtered on quick filtering paper. 100 ml of the filtered liquid is poured in a previously weighed aluminum container, which is heated on a heating plate under nitrogen flow to remove the solvent by evaporation. The container is then kept on an oven at 80 °C under vacuum until a constant weight is obtained. The weight percentage of polymer soluble in xylene at room temperature is then calculated.

[0054] The content of the xylene-soluble fraction is expressed as a percentage of the original 2.5 grams and then, by the difference (complementary to 100%), the xylene insoluble percentage (%);

[0055] XS of components B) and C) have been calculated by using the formula:

[0056] XStot=WaXSA+WbXSB+WcXSC

[0057] wherein Wa, Wb and Wc are the relative amount of components A, B and C, respectively, and (A+B+C=l).Melt Flow Rate (MFR)

[0058] Measured according to ISO 1133 at 230 °C with a load of 2.16 kg, unless otherwise specified.Intrinsic Viscosity (IV)

[0059] The sample is dissolved in tetrahydronaphthalene at 135 °C and then poured into a capillary viscometer. The viscometer tube (Ubbelohde type) is surrounded by a cylindrical glass jacket; this setup allows for temperature control with a circulating thermostatic liquid. The downward passage of the meniscus is timed by a photoelectric device.

[0060] The passage of the meniscus in front of the upper lamp starts the counter which has a quartz crystal oscillator. The meniscus stops the counter as it passes the lower lamp and the efflux time is registered: this is converted into a value of intrinsic viscosity through Huggins' equation (Huggins, M.L., J. Am. Chem. Soc., 1942, 64, 2716) provided that the flow time of the pure solvent is known at the same experimental conditions (same viscometer and same temperature). One single polymer solution is used to determine [ n ].Polydispersity index:

[0061] Determined at a temperature of 200 °C by using a parallel plates rheometer model RMS-800 marketed by RHEOMETRICS (USA), operating at an oscillation frequency whichincreases from 0.1 rad / sec to 100 rad / sec. From the crossover modulus one can derive the P.I. by way of the equation:P.I = 105 / Gc

[0062] in which Gc is the crossover modulus which is defined as the value (expressed in Pa) at which G’=G” wherein G is the storage modulus and G" is the loss modulus.Ethylene (C2) content

[0063] 13C NMR of propylene / ethylene copolymers

[0064] 13C NMR spectra were acquired on a Bruker AV-600 spectrometer equipped with cry oprobe, operating at 160.91 MHz in the Fourier transform mode at 120°C.

[0065] The peak of the Spp carbon (nomenclature according to “Monomer Sequence Distribution in Ethylene-Propylene Rubber Measured by 13C NMR. 3. Use of Reaction Probability Mode ” C. J. Carman, R. A. Harrington and C. E. Wilkes, Macromolecules, 1977, 10, 536) was used as internal reference at 29.9 ppm. The samples were dissolved in 1, 1,2,2- tetrachloroethane-d2 at 120°C with a 8 % wt / v concentration. Each spectrum was acquired with a 90° pulse, 15 seconds of delay between pulses and CPD to remove 1H-13C coupling. 512 transients were stored in 32K data points using a spectral window of 9000 Hz.

[0066] The assignments of the spectra, the evaluation of triad distribution and the composition were made according to Kakugo (“Carbon- 13 NMR determination of monomer sequence distribution in ethylene-propylene copolymers prepared with 8-titanium trichloridediethylaluminum chloride” M. Kakugo, Y. Naito, K. Mizunuma and T. Miyatake, Macromolecules, 1982, 15, 1150) using the following equations:PPP = 100 Tpp / S PPE = 100 Tps / S EPE = 100 T55 / SPEP = 100 Spp / S PEE= 100 Sps / S EEE = 100 (0.25 Syg+0.5 S55) / SS = Tpp + Tps + Tss + Spp + Sps + 0.25 Syg + 0.5 Sss

[0067] The molar percentage of ethylene content was evaluated using the following equation:E% mol = 100 * [PEP+PEE+EEE]

[0068] The weight percentage of ethylene content was evaluated using the following equation:100 * E% mol * MWEE% wt. = >E% mol * MWE + P% mol * MWp

[0069] where P% mol is the molar percentage of propylene content, while MWE and MWp are the molecular weights of ethylene and propylene, respectively.

[0070] The product of reactivity ratio nr? was calculated according to Carman (C.J.Carman, R.A. Harrington and C.E. Wilkes, Macromolecules, 1977; 10, 536) as:

[0071] The tacticity of Propylene sequences was calculated as mm content from the ratio of the PPP mmTpp (28.90-29.65 ppm) and the whole Tpp (29.80-28.37 ppm).

[0072] Ethylene C2 content of component b2 has been measured by measuring the C2 content on component B) and then calculated by using the formula C2tot=XblC2bl+Xb2C2b2 wherein Xbl and Xb2 are the amounts of components bl and b2 in the composition.Samples for the mechanical tests

[0073] Samples have been obtained according to ISO 1873-2:2007.Charpy impact test is determined according to ISO 179-leA, and ISO 1873-2 Elongation at yield: measured according to ISO 527.Elongation at break: measured according To ISO 527 Stress at break: measured according to ISO 527.Tensile Modulus according to ISO 527-2,Melting point and crystallization point

[0074] The melting point has been measured by using a DSC instrument according to ISO 11357-3, at scanning rate of 20C / min both in cooling and heating, on a sample of weight between 5 and 7 mg., under inert N2 flow. Instrument calibration made with Indium.EXAMPLESMaterials

[0075] Component A)

[0076] Component A is a recycled PP having the features reported in table 1Table 1

[0077] Component b)

[0078] Component b) is an heterophasic propylene copolymer sold by LyondellBasell under the tradename Hifax CA138A. The features reported in table 2Table 2Component c)

[0079] Component c) is an heterophasic propylene copolymer sold by LyondellBasell under the tradename Hifax X1956A. The features reported in table 3Table 3C2 ethylene derived unitsComponent d)

[0080] As a component (d) HM05 commercialized by IMI Fabi SpA-Italy (T2) was used.

[0081] As stabilizer AOx 30%: Schulman L AO 230 Q ((30% Irganox B225) was used.Example 1

[0082] A composition blending components a)-d) was obtained according to the amounts reported on table 4Table 4The properties of the composition of example 1 and comparative example 2 are reported in table 5Table 5 - Properties of the final compositions

[0083] Comparative example 2 is example 1 of wo2022 / 090104

[0084] The above data shows that the composition of the present disclosure shows an improved tensile modulus with respect to the composition of the comparative example.

Claims

CLAIMSWhat is claimed is:

1. A polypropylene composition comprising:(a) from 60.0 wt% to 85.0 wt% of a recycled polypropylene (r-PP) wherein the recycled polypropylene composition (A) has : a propylene content, measured with13C-NMR, higher than 60 wt%, Melt Flow Rate (ISO 1133 230°C / 2.16 kg) ranging from 35 to 74 g / lOmin;Tensile modulus, measured according to ISO 527-2, ranging from 620N / mm2to 1620 N / mm2Charpy impact test at 23°C, determined according to ISO 179-leA, and ISO 1873-2, ranging from 2.2 KJ / m2to 12.0 KJ / m2;Elongation at break, measured according To ISO 527, ranging from 7 % to 37 %; the FTIR spectrum of film recorded as described in the example section shows at least two peaks at different wavenumbers (cm-1) selected from:3303 ±1 cm-1; 1642 ±1 cm-1; 1550 ±1 cm-1; 1726 ±1 cm-1; 1600 ±11 cm-1, 748 ±1 cm-1; 695 ±1 cm-1;(b) from 10.0 wt% to 30.0 wt% of a composition comprising; bl) from 29 wt% to 59 wt%; of a propylene homopolymer having a xylene soluble lower than 4.0 wt%; and a melt flow rate (ISO 1133 230°C / 2.16 kg) ranging from 65 g / 10 min to 120 g / 10 min; b2) from 41 wt% to 71 wt% %; of a propylene ethylene copolymer containing from 30.8 wt% to 62.0 wt%; of ethylene derived units measured according to13C-NMR method described in the specification; said composition being further characterized by: a Melt Flow Rate (ISO 1133 230°C / 5.0 kg) ranging from 0.5 to 11.2 g / 10min; an amount of fraction soluble in xylene at 25°C ranging from 35.0 wt% to 58.0 wt%; intrinsic viscosity of the fraction soluble in xylene at 25°C, measured in tetrahydronaphthalene at 135 °C, ranging from 2.3 to 4.9 dl / g;total content of ethylene, measured according to13C-NMR method described in the specification, ranging from 19.2 wt% to 35.9 wt%;(c) from 0.5wt% to 6.0 wt%; of a propylene ethylene copolymer composition comprising; i) fraction soluble in xylene at 25°C ranging from 20 wt% to 38 wt%; ii) the melt flow rate (230°C / 2.16 kg.. ISO 1133) ranging from 0.4 g / lOmin to 4.0 g / lOmin iii) intrinsic viscosity, measured in tetralin, of the fraction soluble in xylene at 25°C ranging from 5.7 dl / g to 9.2 dl / g; said propylene, ethylene copolymer composition component c) comprising: cl) from 27 wt% to 40 wt%; of a propylene homopolymer having a melt flow rate MFR1 (230°C / 2.16 kg. ISO 1133) ranging from 62.0 g / lOmin to 100.0 g / lOmin; c2) from 27 wt% to 40 wt% of a propylene homopolymer having a melt flow rate MFR2 (230°C / 2.16 kg. ISO 1133) lower than MFR1 ; c3) from 20 wt% to 46 wt% of a propylene ethylene copolymer having a content of ethylene derived units ranging from 18.0 wt% to 48.0 wt%;(d) from 1 to 6% by weight of an inorganic filler; the whole composition having a value of melt flow rate (ISO 1133 230°C / 2.16 kg) ranging from 10 g / 10’ to 50 g / 10’, preferably 18.0 g / 10’ to 50 g / 10’, more preferably from 20 to 45g / 10’, especially from 23 to 35 g / 10’; the percentages of (a) to (d) being referred to the total weight of the polypropylene composition.

2. The polypropylene compositions according to claim 1 wherein: component (a) ranges from 63.0 wt% to 80.0 wt %,; component (b) ranges from 12.0wt% to 26.0 wt%; component (c) ranges from 1.0 wt% to 5.0wt%; component (d) ranges from 1.0 wt% to 5.0wt%.

3. The polypropylene compositions according to anyone of claims 1-2 wherein recycled PP component (a) has the Melt Flow Rate (ISO 1133 230°C / 2.16 kg) ranging from 41 to 68 g / lOmin.

4. The polypropylene compositions according to anyone of claims 1-3 having a melt flow rate (ISO 1133 230°C / 2.16 kg) ranging from 8.0 g / 10 min to 38.0 g / 10.

5. The polypropylene compositions according to anyone of claims 1-4 wherein in component(b) bl) ranges from 34 wt% to 54 wt%; and b2) ranges from 46 wt% to 66 wt%.

6. The polypropylene compositions according to anyone of claims 1-5 wherein component(b) has an amount of fraction soluble in xylene at 25°C ranging from 38.0 wt% to 56.0 wt%.

7. The polypropylene compositions according to anyone of claims 1-6 wherein in component(c) contains from 30 to 80% of component (i) and the MFR of its fractions Al and A2 is such that the ratio MFRII / MFRIrange from 40 to 2000.

8. The polypropylene compositions according to anyone of claims 1-7 wherein in component(c) cl) ranges from 29 wt% to 38 wt%; c2) ranges from 29 wt% to 38 wt%; c3) ranges from 24 wt% to 42 wt%;9. The polypropylene compositions according to anyone of claims 1-8 wherein in component c) the intrinsic viscosity, measured in tetralin, of the fraction soluble in xylene at 25°C ranges from 6.0 dl / g to 8.

10. The polypropylene compositions according to anyone of claims 1-9 wherein the component (d) is selected from talc, fiber glass, CaCCh, clays carbon black and mica.

11. The polypropylene composition according to anyone of claim 1-10 wherein the component(d) is talc of average particle size lower than 5 pm.

12. The polypropylene composition according to anyone of claim 1-11 wherein in component b) the intrinsic viscosity of the fraction soluble in xylene at 25°C, measured in tetrahydronaphthalene at 135 °C, ranges from 2.6 to 4.5 dl / g.

13. The polypropylene composition according to anyone of claim 1-11 wherein in component b) the total content of ethylene, measured according to13C-NMR method described in the specification, ranges from 22.4 wt% to 33.8 wt%.

14. The polypropylene composition according to anyone of claim 1-13 wherein in component b) the amount of fraction soluble in xylene at 25°C ranges from 38.0 wt% to 56.0 wt%.

15. An injection molded article made from composition according to claims 1-14.

Citation Information

Patent Citations

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