Polyolefin compositions obtained from recycled polyolefins

Abstract

A polyolefin composition comprising: A) from 20 wt% to 80 wt% of a recycled polypropylene composition; B) from 20 wt% to 80 wt% of a virgin polypropylene composition comprising: - (b1) from 75 wt% to 95 wt%, of a propylene homopolymer - (b2) from 5 wt% to 25 wt % of a copolymer of propylene and ethylene having: -units derived from ethylene, measured according to 13C-NMR, in an amount ranging from 35.0wt% to +68.0 wt% in the said composition the sum of b1) and b2), being referred to the total weight of b1) and b2), is 100, and the sum of the amounts of (A) and (B) being referred to the total weight of (A) and (B) is 100.

Description

POLYOLEFIN COMPOSITIONS OBTAINED FROM RECYCLED POLYOLEFINSFIELD OF THE INVENTION

[0001] The present disclosure relates to polypropylene compositions containing recycled elastomeric material that can be used in preparation of extruded articles.BACKGROUND OF THE INVENTION

[0002] Polyolefin compositions having elastic properties while maintaining a good thermoplastic behavior have been used in many application fields, due to the valued properties which are typical of polyolefins, such as chemical inertia, mechanical properties and nontoxicity. Moreover, they can be advantageously transformed into finished products with the same techniques used for thermoplastic polymers. In particular, flexible polymer materials are widely used in the medical field, as well as for packaging, extrusion coating and electrical wires and cables covering.

[0003] Elastic polypropylene compositions retaining good thermoplastic behavior have been obtained in the art by way of sequential copolymerization of propylene, optionally containing minor quantities of olefin comonomers, and then ethylene / propylene or ethylene / alpha-olefin copolymers mixtures. Catalysts based on halogenated titanium compounds supported on magnesium chloride are commonly used for this purpose. For instance, EP-A-472 946 describes flexible elastoplastic polyolefin compositions comprising, in parts by weight: A) 10-50 parts of an isotactic propylene homopolymer or copolymer; B) 5-20 parts of an ethylene copolymer, insoluble in xylene at room temperature; and C) 40-80 parts of an ethylene / propylene copolymer containing less than 40% by weight of ethylene and being soluble in xylene at room temperature; the intrinsic viscosity of said copolymer is preferably from 1.7 to 3 dl / g. Said compositions are relatively flexible and have good elastic properties.

[0004] In addition, 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 replacing, at least in part, virgin polyolefin compositions with variable amounts of recycled plastic materials.

[0006] The recycled plastic polyolefin derive from streams of post-consumer waste (PCW) or post-industrial waste (PIW).

[0007] One of the key problems in polyolefin recycling, is the difficulty to quantitatively separate the various types of polymers so that the commercially available recycled products are almost invariably contaminated with heterogeneous materials of various source.

[0008] This fact leads to the consequence that polymer compositions including recycled materials are perceived of being affected by lower reliability and lower performances with respect to the compositions made of solely virgin polymers.

[0009] It has now been unexpectedly found that it is possible to have an improved property profile especially in terms of impact and modulus values when a recycled polymers is added to a virgin polypropylene.SUMMARY OF THE INVENTION

[0010] It is therefore an object of the present disclosure a polyolefin composition comprising:A) from 20 wt% to 80 wt% of a recycled polypropylene composition;B) from 20 wt% to 80 wt% of a virgin polypropylene composition comprising:(bl) from 75 wt% to 95 wt%, of a propylene homopolymer, having: a fraction soluble in xylene at 25°C lower than 6.0 wt%; and a Melt Flow Rate (ISO 1133 230°C / 2.16 kg) ranging from 0.1 to 6.0 g / lOmin;(b2) from 5 wt% to 25 wt % of a copolymer of propylene and ethylene having: units derived from ethylene, measured according to13C-NMR, in an amount ranging from 25.0 wt% to 68.0 wt%; said polypropylene composition (B) being further characterized by: a Melt Flow Rate (ISO 1133 230°C / 5.0 kg)ranging from 0.4 to 3.0 g / lOmin; an amount of fraction soluble in xylene at 25°C ranging from 7.0 wt% to 18.0 wt%; intrinsic viscosity of the fraction soluble in xylene at 25°C, measured in tetrahydronaphthalene at 135 °C, ranging from 3.0 to 7.5 dl / g and, total content of ethylene measured according to13C-NMR method described in the specification, ranging from 4.0 wt% to 7.0 wt%; in the said composition the sum of bl) and b2), being referred to the total weight of bl) and b2), is 100, and the sum of the amounts of (A) and (B) being referred to the total weight of (A) and (B) is 100.DETAILED DESCRIPTION OF THE INVENTION

[0011] It is therefore an object of the present disclosure a polyolefin composition comprising:A) from 20 wt% to 80 wt%; preferably from 40 wt% to 75 wt%; more preferably from 47 wt% to 72 wt%; even more preferably from 45 wt% to 55 wt% of a recycled polypropylene composition;B) from 20 wt% to 80 wt%; preferably from 25 wt% to 60 wt%; more preferably from 28 wt% to 53 wt%; even more preferably from 45 wt% to 55 wt% of a virgin polypropylene composition comprising:- (bl) from 75 wt% to 95 wt%, preferably from 81 wt% to 93 wt%; more preferably from 85 wt% to 92 wt% of a propylene homopolymer, having: a fraction soluble in xylene at 25°C lower than 6.0 wt%; preferably lower than 3.0 wt%; more preferably lower than 2.8 wt%; even more preferably lower than 2.2 wt%; preferably being higher than 0.5 wt% and a Melt Flow Rate (ISO 1133 230°C / 5.0 kg) ranging from 0.1 to 6.0 g / lOmin; preferably ranging from 0.5 to 2.5 g / lOmin; more preferably ranging from 0.6 to 1.7 g / lOmin;- (b2) from 5 wt% to 25 wt%; preferably from 7 wt% to 19 wt%; more preferably from 8 wt% to 15 wt% of a copolymer of propylene and ethylene having: units derived from ethylene, measured according to13C-NMR, in an amount ranging from 25.0 wt% to 68.0 wt%; preferably from 35.0 wt% to 68.0 wt%; more preferably ranging from 41.0 wt% to 57.0 wt%; even more preferably ranging from 46.0 wt% to 54.0 wt %; said polypropylene composition (B) being further characterized by: a Melt Flow Rate (ISO 1133 230°C / 5.0 kg) ranging from 0.4 to 5.0 g / 10 min; preferably from 0.4 to 3.0 g / lOmin; more preferably ranging from 0.5 to 2.50 g / lOmin; even more preferably ranging from 0.6 to 1.7 g / lOmin; an amount of fraction soluble in xylene at 25°C ranging from 7.0 wt% to 18.0 wt%; preferably from 8.0 wt% to 16.0 wt% ; more preferably from 8.5 wt% to 12.4 wt%; intrinsic viscosity fraction soluble in xylene at 25°C, measured in tetrahydronaphthalene at 135 °C, ranging from 1.2 to 7.5 dl / g; preferably from 3.0 to 7.5 dl / g; more preferably ranging from 3.5 to 5.5 dl / g; even more preferably ranging from 3.7 to 5.2 dl / g and,total content of ethylene measured according to13C-NMR method described in the specification, ranging from 4.0 wt% to 10.0 wt%; preferably from 4.0 wt% to 7.0 wt%; more preferably ranging from 4.2 wt% to 5.8 wt%; even more preferably ranging from 4.5 wt% to 5.4 wt%; in the said composition the sum of bl) and b2), being referred to the total weight of bl) and b2), is 100, and the sum of the amounts of (A) and (B) being referred to the total weight of (A) and (B) is 100.

[0012] The term “copolymer” as used herein refers to polymers with two different recurring units.

[0013] The term "recycled" is used to designate polymer materials deriving from at least one cycle of processing into manufactured articles, as opposed to virgin polymers that is a polymer not subjected at least one cycle of processing into manufactured articles.

[0014] The term “consisting essentially of’, as used herein in connection with a polymer or polymer composition means that, in addition to those components which are mandatory, other components may also be present in the polymer or in the polymer composition, provided that the essential characteristics of the polymer or of the composition are not materially affected by their presence. According to the present disclosure, examples of components that, when present in customary amounts in a polymer or in a polymer composition, do not materially affect their characteristics are the catalyst residues, antistatic agents, melt stabilizers, light stabilizers, antioxidants, antiacids.

[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 (B) and any preferred range of features of components (A) to (B) can be combined with any preferred range of one or more of the features of components (A) to (B) and with any possible additional component, and its features, described in the present disclosure.

[0016] The melting temperature of the component bl), determined via DSC, preferably ranges from 155°C to 165°C.

[0017] Component B) can be prepared by polymerizing propylene, optionally in mixture with ethylene in the presence of a catalyst comprising the product of the reaction between:i) a solid catalyst component comprising Ti, Mg, Cl, and at least an internal electron donor compound; ii) an alkylaluminum compound and, iii) an external electron-donor compound having the general formula:(R7)a(R8)bsi(OR9)c, where a and b are integers from 0 to 2, c is an integer from 1 to 4 and the sum (a+b+c) is 4; R7, R8, and R9, are alkyl, cycloalkyl or aryl radicals with 1-18 carbon atoms optionally containing heteroatoms.

[0018] The internal donor is preferably selected from the esters of mono or dicarboxylic organic acids such as benzoates, malonates, phthalates and certain succinates. Examples of internal donors are described in US 4522930A, EP 045977A2 and international patent applications WO 00 / 63261 and WO 01 / 57099. Particularly suited are the phthalic acid esters and succinate acids esters. Alkylphthalates are preferred, such as diisobutyl, dioctyl and diphenyl phthalate and benzyl-butyl phthalate.

[0019] The particles of solid component (i) may have substantially spherical morphology and average diameter ranging between 5 and 150 pm, preferably from 20 to 100 pm and more preferably from 30 to 90 pm. As particles having substantially spherical morphology, those are meant wherein the ratio between the greater axis and the smaller axis is equal to or lower than 1.5 and preferably lower than 1.3.

[0020] The amount of Mg may preferably range from 8 to 30% more preferably from 10 to 25wt. %.

[0021] The amount of Ti may range from 0.5 to 7% and more preferably from 0.7 to 5wt. %.

[0022] According to one method, the solid catalyst component (i) can be prepared by reacting a titanium compound of formula Ti(OR)q-yXy, where q is the valence of titanium and y is a number between 1 and q, preferably TiC14, with a magnesium chloride deriving from an adduct of formula MgC12»pROH, where p is a number between 0.1 and 6, preferably from 2 to 3.5, and R is a hydrocarbon radical having 1-18 carbon atoms. The adduct can be suitably prepared in spherical form by mixing alcohol and magnesium chloride, operating under stirring conditions at the melting temperature of the adduct (100-130°C). Then, the adduct is mixed with an inert hydrocarbon immiscible with the adduct thereby creating an emulsion which is quickly quenched causing the solidification of the adduct in form of spherical particles. Examples of spherical adducts prepared according to this procedure are described in USP 4,399,054 and USP 4,469,648.The so obtained adduct can be directly reacted with Ti compound or it can be previously subjected to thermal controlled dealcoholation (80-130°C) so as to obtain an adduct in which the number of moles of alcohol is of lower than 3, preferably between 0.1 and 2.5. The reaction with the Ti compound can be carried out by suspending the adduct (dealcoholated or as such) in cold TiC14; the mixture is heated up to 80-130°C and kept at this temperature for 0.5-2 hours. The treatment with TiC14 can be carried out one or more times. The electron donor compound can be added in the desired ratios during the treatment with TiC14.

[0023] The alkyl-Al compound (ii) is preferably chosen among the trialkyl aluminum compounds such as for example tri ethylaluminum, triisobutylaluminum, tri-n-butylaluminum, tri- n-hexylaluminum, tri-n-octylaluminum. It is also possible to use alkylaluminum halides, alkylaluminum hydrides or alkylaluminum sesqui chlorides, such as AlEt2Cl and A12Et3C13, possibly in mixture with the above cited trialkylaluminums. The Al / Ti ratio is higher than 1 and may preferably range between 50 and 2000.

[0024] Particularly preferred are the silicon compounds (iii) in which a is 1, b is 1, c is 2, at least one of R7 and R8 is selected from branched alkyl, cycloalkyl or aryl groups with 3-10 carbon atoms optionally containing heteroatoms and R9 is a Cl -CIO alkyl group, in particular methyl. Examples of such preferred silicon compounds are methylcyclohexyldimethoxysilane (C donor), diphenyldimethoxysilane, methyl-t-butyldimethoxysilane, dicyclopentyldimethoxysilane (D donor), diisopropyldimethoxysilane, (2-ethylpiperidinyl)t-butyldimethoxysilane, (2- ethylpiperidinyl)thexyldimethoxysilane, (3,3,3-trifluoro-n-propyl)(2- ethylpiperidinyl)dimethoxysilane, methyl(3,3,3-trifluoro-n-propyl)dimethoxysilane. Moreover, are also preferred the silicon compounds in which a is 0, c is 3, R8 is a branched alkyl or cycloalkyl group, optionally containing heteroatoms, and R9 is methyl. Examples of such preferred silicon compounds are cyclohexyltrimethoxysilane, t-butyltrimethoxysilane and thexyltrimethoxysilane.

[0025] The external electron donor compound (iii) is used in such an amount to give a molar ratio between the organoaluminum compound and said external electron donor compound (iii) of from 0.1 to 200, preferably from 1 to 100 and more preferably from 3 to 50.

[0026] Component B) can be prepared in a continuous sequential polymerization process, wherein component bl) is prepared in the first reactor and component (b2) is prepared in the second reactor in the presence of component bl) according to the known techniques and operatingin gas phase, or in liquid phase in the presence or not of inert diluent, or by mixed liquid-gas techniques.

[0027] Component B) is preferably a commercial polymer grade such as Hostalen PP H2483 sold by Lyondellbasell.

[0028] Component (A) can origin either from post-consumer waste (PostCW) or from preconsumer waste (Pre-CW). Preferably, it origins from Pre-CW. The pre-consumer plastic is regarded as a plastic waste diverted from a manufacturing process which is not reutilized such as rework, regrind or scrap, and is not reincorporated in the same process that generated it.

[0029] The melt flow rate (ISO 1133-1 230°C / 2.16 kg) of the whole component (A) can generally range from 0.5 to 30.0 g / 10 min, preferably from 1.0 to 25.0 g / 10 min and more preferably from 2.0 to 20.0 g / 10 min.

[0030] If needed, the final composition comprising (A)+(B) can be subject to a chemical treatment with organic peroxides in order to lower the average molecular weight and increase the melt flow index up to the value needed for the specific application.

[0031] The whole polypropylene composition of the present disclosure preferably shows a tensile modulus value lower than that of component B). Preferably embodiment, the tensile modulus of the whole propylene polymer composition ranges from to 750 MPa to 1700 MPa more preferably from 900 to 1650 MPa.

[0032] The value of Charpy impact at 23°C ranges from 30.0 Kj / m2to 5.0 Kj / m2; the value of Charpy impact at 0°C ranges from 2.0 Kj / m2to 10.0 Kj / m2; the value of Charpy impact at - 20°C ranges from 1.0 Kj / m2to 7.0 Kj / m2.

[0033] The whole propylene composition of the present disclosure can be obtained by mechanical blending of the components (A) and (B) according to conventional techniques.

[0034] The final composition comprising the components (A) and (B) may be added with conventional additives, fillers and pigments, commonly used in olefin polymers such as nucleating agents, extension oils, mineral fillers, and other organic and inorganic pigments. In particular, the addition of inorganic fillers, such as talc, calcium carbonate and mineral fillers, also brings about an improvement to some mechanical properties, such as flexural modulus and HDT. Talc can also have a nucleating effect.

[0035] The nucleating agents may be added to the compositions of the present disclosure in quantities ranging from 0.05 wt% to 2 wt%, more preferably from 0.1 wt% to 1 wt%, with respect to the total weight, for example.

[0036] The propylene polymer composition of the present disclosure can be extruded to form films or sheets or thermoformed for a variety of applications. Particularly preferred is the use of the polypropylene composition for the preparation of thermoformed object.

[0037] In particular thermoformed objects for non-food applications can be prepared such as trays and containers for consumer goods. For food application trays and containers for food, thermoformed from a three layers co-extruded ABA sheet, where the B layer is the propylene polymer composition of the present disclosure and the A layers are made of virgin materials and act as functional barrier.

[0038] As shown in the examples below, the composition employing the component B) shows a synergistic behavior with the component A. In fact, by adding component B) in the amounts according to the invention it is possible to obtain a copolymer having high impact values with relatively low modulus.

[0039] The polyolefin composition of the present disclosure shows a quite unique properties with low MFR, very high stiffness and good impact properties, guarantying an increased melt strength and good processability a good compatibilization of the different polymeric phases.

[0040] The following examples are given in order to illustrate, but not limit the present disclosure.EXAMPLESCHARACTERIZATIONSXylene-soluble (XS) Fraction at 25 °C

[0041] 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 30 minutes. 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.

[0042] 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 (%).Melt Flow Rate (MFR)

[0043] Measured according to ISO 1133-1 at 230 °C with a load of 2.16 kg or 5 kg, as specified.Intrinsic Viscosity (IV)

[0044] 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.

[0045] 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: Determined at a temperature of 200 °C by using a parallel plates rheometer model RMS-800 marketed by RHEOMETRICS (USA), operating at an oscillation frequencywhich increases 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 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) content13C NMR of propylene / ethylene copolymers

[0046] 13C NMR spectra were acquired on a Bruker AV-600 spectrometer equipped with cryoprobe, operating at 160.91 MHz in the Fourier transform mode at 120°C.

[0047] 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.

[0048] 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, 4, 1150-1152) using the following equations:PPP = 100 Tpp / S PPE = 100 Tps / S EPE = 100 Tss / 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

[0049] The molar percentage of ethylene content was evaluated using the following equation:E% mol = 100 * [PEP+PEE+EEE]The weight percentage of ethylene content was evaluated using the following equation:100 * E% mol * MWEE% wt. = >E% mol * MWE+ P% mol * MWp

[0050] where P% mol is the molar percentage of propylene content, while MWE and MWp are the molecular weights of ethylene and propylene, respectively.

[0051] 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:

[0052] 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).Samples for the mechanical tests

[0053] Samples have been obtained according to ISO 1873-2:2007.Charpy impact test is determined according to ISO 179-leA, and ISO 1873-2Elongation at yield: measured according to ISO 527.Elongation at break: measured according To ISO 527Stress at break: measured according to ISO 527.Tensile Modulus according to ISO 527-2,Tear Resistance according to the method ASTM D 1004 on Imm-thick extruded sheets. Crosshead speed: 51 mm / min; V-shaped die cut specimen.Shore D on injection molded, compression molded plaques and extruded sheets according to the method ISO 868 (15 sec)Melting point and crystallization point

[0054] 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.EXAMPLESExample 1Component A)

[0055] The recycled polypropylene used as component A) is sold by QCP with the tradename QCP300P. It contains residue-drained, rigid, system-compatible items made of polypropylene, volume < 5 litres, e.g. bottles, bottles, cups and trays, incl. secondary components such as lids, labels etc.

[0056] Purity is at least 94 wt%, metallic and mineral impurities with a unit weight of > 100 g and cartridges for sealants are not permitted!

[0057] Impurities

[0058] Examples of other residues are:GlassPaper, Board, CardboardComposite paper / cardboard materials (e.g. liquid packaging boards)Aluminized plasticsOther materials (e.g. rubber, stones, wood, textiles, nappies)Compostable waste (e.g. food, garden waste)

[0059] The Melt flow rate (230 °C / 2.16 kg) of component A) is 16 g / 10 min and the melting point is 150°CComponent B)

[0060] Component B is a commercial grade Hostalen H2483, it can be synthesized according to the procedure known in the art, Hostalen H248 has the property set forth in table 1 :Table 1Xs fraction soluble in xylene at 25 °CC2 ethylene derived unitsIV intrinsic viscosity

[0061] 50 wt% of component A) has been blended with 50 wt% of component B) in an extruder (Berstorff extruder), 1000 ppm of M.S. 168 and 3000 ppm of DHT-4A based on the total wigth of A + B have been added. The polymer particles are extruded under nitrogen atmosphere in a twin screw extruder, at a rotation speed of 250 rpm and a melt temperature of 200-250° C. The characterization of the obtained composition is reported in table 2.Table 2

[0062] Comparative example 2 is a commercial grade HP740J sold by Lyondellbasell. HP740J is a nucleated homopolymer fit for extrusion and thermoforming applications. The polymer compositions according to the present disclosure have an improved balance of softness and mechanical properties to be used for thermoforming application.Example!Component A)The recycled polypropylene used as component A) is sold by polar, the features of the recycled polypropylene are reported on table 3Table 3C2 ethylene derived unitsComponent B)Component B) is is a commercial grade Hostalen H2483 used in example 1.

[0063] 70 wt% of component A) has been blended with 30 wt% of component B) in an extruder (Berstorff extruder), 1000 ppm of M.S. 168 and 3000 ppm of DHT-4A based on the total wigth of A + B have been added. The polymer particles are extruded under nitrogen atmosphere in a twin screw extruder, at a rotation speed of 250 rpm and a melt temperature of 200-250° C. The characterization of the obtained composition is reported in table 4.Table 4

Claims

CLAIMSWhat is claimed is:

1. A polyolefin composition comprising:A) from 47 wt% to 72 wt%;of a recycled polypropylene composition;B) from 28 wt% to 53 wt% of a virgin polypropylene composition comprising:- (bl) from 75 wt% to 95 wt%, of a propylene homopolymer, having: a fraction soluble in xylene at 25°C lower than 6.0 wt%; and a Melt Flow Rate (ISO 1133 230°C / 2.16 kg) ranging from 0.1 to 6.0 g / lOmin- (b2) from 5 wt% to 25 wt % of a copolymer of propylene and ethylene having:-units derived from ethylene, measured according to13C-NMR, in an amount ranging from 25.0 wt% to 68.0 wt%; said polypropylene composition (B) being further characterized by- a Melt Flow Rate (ISO 1133 230°C / 5.0 kg)ranging from 0.4 to 5.0 g / lOmin;- an amount of fraction soluble in xylene at 25°C ranging from 7.0 wt% to 18.0 wt%- intrinsic viscosity fraction soluble in xylene at 25°C, measured in tetrahydronaphthalene at 135 °C, ranging from 1.2 to 7.5 dl / g and,- a total content of ethylene measured according to13C-NMR method, ranging from 4.0 wt% to 10.0 wt%; in the said composition the sum of bl) and b2), being referred to the total weight of bl) and b2), is 100, and the sum of the amounts of (A) and (B) being referred to the total weight of (A) and (B) is 100.

2. The propylene polymer composition according to claim 1 wherein the component (A) ranges from 45 wt% to 55 wt%;and component (B) ranges from 45 wt% to 55 wt%.

3. The propylene polymer composition according to claims 1 or 2 wherein in component B) component bl) ranges from 81 wt% to 93 wt% and component b2) ranges from 7 wt% to 19 wt %.

4. The propylene polymer composition according to any of the preceding claims wherein component bl) has a Melt Flow Rate (ISO 1133 230°C / 5.0 kg) ranging from 0.5 to 2.50 g / lOmin.

5. The propylene polymer composition according to any of the preceding claims wherein in component b2) the units derived from ethylene, measured according to13C-NMR, in an amount ranges from 41.0 wt% to 57.0 wt%.

6. The propylene polymer composition according to any of the preceding claims wherein component B) has the Melt Flow Rate (ISO 1133 230°C / 5.0 kg) ranging from 0.4 to 3.0 g / lOmin.

7. The propylene polymer composition according to any of the preceding claims wherein component (B) has the amount of fraction soluble in xylene at 25°C ranging from 8.0 wt% to 16.0 wt%.

8. The propylene polymer composition according to any of the preceding claims wherein component (B) has the intrinsic viscosity fraction soluble in xylene at 25°C, measured in tetrahydronaphthalene at 135 °C, ranging from 3.0 to 7.5 dl / g.

9. The propylene polymer composition according to any of the preceding claims wherein in component (B) the total content of ethylene measured according to13C-NMR method ranges from 4.2 wt% to 5.8 wt%.

10. The propylene polymer composition according to a to any of the preceding claims wherein in component A) the melt flow rate (ISO 1133-1 230°C / 2.16 kg) of the whole component (A) can generally range from 0.5 to 30.0 g / 10 min.

11. The propylene polymer composition according to any of the preceding claims wherein in component (B) the total content of ethylene measured according to13C-NMR method ranges from 4.5 wt% to 5.4 wt%.

12. The propylene polymer composition according to any of the preceding claims wherein component (B) has the intrinsic viscosity fraction soluble in xylene at 25°C, measured in tetrahydronaphthalene at 135 °C, ranging from 3.7 to 5.2 dl / g.

13. The propylene polymer composition according to any of the preceding claims wherein component (B) has the amount of fraction soluble in xylene at 25°C ranging from 8.5 wt% to 12.4 wt%.

14. The propylene polymer composition according to any of the preceding claims wherein component B) has the Melt Flow Rate (ISO 1133 230°C / 5.0 kg) ranging from 0.6 to 1.7 g / lOmin.

15. A thermoformed article obtained from the propylene polymer composition according to any of the preceding claims.

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