Propylene-based copolymer compositions

Abstract

A polyolefin composition comprising: A) 70 to 90 wt% of a copolymer of propylene and ethylene, wherein: the content of ethylene-derived units as measured by NMR is from 3.3 to 6.0 wt%; and B) 10 to 30 wt% of a propylene-ethylene copolymer containing 3.6 to 7.5 wt% of ethylene-derived units as measured by NMR, and having a melt flow rate (230°C / 2.16 kg, ISO 1133) in the range of from 0.6 to 10 g / 10 min; wherein the resulting polyolefin composition has: an ethylene-derived unit content as measured by NMR of from 3.5 to 5.5 wt%; a xylene soluble content at 25°C in the range of from 5.1 to 12.0 wt%; the difference between the ethylene-derived unit content of component B and the ethylene-derived unit content of component A (C2B-C2A) in the range of from 0.3 to 5.0 wt%; and the sum of A+B is 100.

Description

Technical Field

[0001] The present disclosure relates to a composition comprising a propylene ethylene copolymer. The composition has particularly balanced properties, particularly a high flexural modulus / haze ratio. The composition is particularly suitable for producing blow molded articles, particularly bottles. Background Art

[0002] It is well known in the polymer industry that different applications require specifically tailored polymers to achieve their desired properties. For example, a polymer used for injection molding must have different properties than a polymer used for blow molding.

[0003] For example, the extrusion blow molding process is a very specific process that allows bottles of different sizes and shapes to be produced in a flexible and inexpensive manner. A major disadvantage of this process is the complex curing step compared to conventional injection molding.

[0004] As a result, extrusion blow molded articles (such as bottles) typically exhibit inferior optical properties compared to any injection molded article. For example, the surface properties of an extrusion blow molded bottle, both internally and / or externally, are often non-uniform (flow lines, melt fracture), resulting in reduced overall gloss and clarity compared to injection molded or injection stretch blow molded bottles. When it is desired to produce a flexible article, the article must have low haze and low flexural modulus. High flexural modulus products are typically associated with low haze, so when it is desired to reduce the flexural modulus to achieve a flexible product, the haze is compromised.

[0005] Therefore, it is desirable to have a polymer that exhibits a specific balance of flexural modulus and haze, such that optical properties can be improved even at lower modulus. This property can be expressed as the flexural modulus / haze ratio.

[0006] WO 2014 / 173533 relates to a multimodal polypropylene composition suitable for pipe applications comprising a multimodal propylene copolymer (U) with a total amount of 4.0 to 10.0 mol% of at least one comonomer selected from α-olefins having 2 or 4 to 8 carbon atoms,

[0007] wherein the multimodal polypropylene composition has a melt flow rate MFR2 (2.16 kg, 230°C) determined according to ISO 1133 of 0.25 to 1.00 g / 10 min, a xylene cold solubles (XCS) content determined at 25°C according to ISO 16152 of 4.0 to 17.0 wt.-%, and a polydispersity index PI of 2.5 to 4.0 Pa-1.

[0008] The MFR of the first propylene polymer is from 1.0 g / 10 min to 5.0 g / 10 min, and the MFR of the second propylene copolymer is from 0.1 g / 10 min to 0.6 g / 10 min.

[0009] WO2016 / 012199 relates to a polyolefin composition comprising:

[0010] A) 90 to 99% by weight of a copolymer of propylene and ethylene, wherein:

[0011] i) an ethylene-derived unit content of 1.0 wt% to 8.0 wt%;

[0012] B) 1.0 to 10.0 wt% of a propylene ethylene copolymer containing 8.0 to 20.0 wt% of ethylene-derived units. The polyolefin composition is used for pipes.

[0013] WO2020 / 148319 relates to a propylene polymer composition for extrusion blow molding, comprising at least one propylene copolymer (C-PP) and an α-nucleating agent (N), wherein the propylene copolymer (C-PP) comprises two propylene copolymer fractions (PP1) and (PP2), wherein the propylene copolymer fraction (PP1) is contained in the propylene copolymer (C-PP) in an amount of 30 to 70 wt.-%, and the propylene copolymer fraction (PP2) is contained in the propylene copolymer (C-PP) in an amount of 70 to 30 wt.-%.

[0014] The comonomer content of the propylene copolymer fraction (PP1) is in the range of 0.5 to 2.6 wt.-% and is lower compared to the comonomer content of the propylene copolymer fraction (PP2), and the propylene polymer composition has a melt flow rate MFR2 (230°C), measured according to ISO 1133, of 1 to 5 g / 10 min.

[0015] In the extrusion blow molding (EBM) process, a polymer melt is first extruded through a tubular die into air to form a polymer tube. This tube (often referred to as a "parison" in the art) is then inflated until the outside of the tube reaches the confines of the mold. Compared to injection molding, completely covering the mold walls with the inflated polymer tube is considerably more difficult because the air between the polymer tube and the mold must be completely removed, a demanding process step. Furthermore, the interior of the polymer tube does not come into contact with the mold, and therefore the potential for affecting the tube's inner surface structure is minimal.

[0016] Applicants have discovered that by fine-tuning these two components a balance between the optical properties and the softness of the composition can be achieved. Summary of the Invention

[0017] Therefore, the object of the present disclosure is a polyolefin composition comprising:

[0018] A) 70 to 90 wt. % of a copolymer of propylene and ethylene, wherein:

[0019] i) a content of ethylene-derived units of from 3.3% to 6.0% by weight as measured by NMR;

[0020] ii) a melting temperature ranging from 132° C. to 143° C. as measured by DSC;

[0021] iii) melt flow rate (230°C / 2.16 kg, ISO 1133) ranging from 1.1 g / 10 min to 3.5 g / 10 min;

[0022] iv) a xylene soluble matter at 25°C ranging from 4.0 wt% to 10.0 wt%;

[0023] B) 10 to 30 wt% of a propylene ethylene copolymer containing 3.6 to 7.5 wt% of ethylene-derived units as measured by NMR, and having a melt flow rate (230°C / 2.16 kg, ISO 1133) in the range of from 0.6 to 10 g / 10 min;

[0024] The obtained polyolefin composition has:

[0025] i) a content of ethylene-derived units of 3.5 to 5.5 wt% as measured by NMR;

[0026] ii) a content of ethylene-derived units in the fraction soluble in xylene at 25° C., as measured by NMR, of from 15.2% to 23.2% by weight;

[0027] iii) melt flow rate (ISO 1133 (230° C., 2.16 kg) ranging from 1.0 g / 10 min to 4.0 g / 10 min;

[0028] iv) a xylene soluble matter at 25° C. ranging from 5.1 wt % to 12.0 wt %;

[0029] v) the intrinsic viscosity of the fraction soluble in xylene at 25°C, measured in tetralin at 135°C, ranges from 0.6 dl / g to 2.5 dl / g;

[0030] vi) the difference between the ethylene-derived unit content of component B and the ethylene-derived unit content of component A (C2B-C2A) ranges from 0.3 wt% to 5.0 wt%;

[0031] The sum of A+B is 100. DETAILED DESCRIPTION

[0032] Therefore, the object of the present disclosure is a polyolefin composition comprising:

[0033] A) 70 to 90 wt.-%, preferably 72 to 88 wt.-%, more preferably 73 to 86 wt.-% of a copolymer of propylene and ethylene, wherein:

[0034] i) a content of ethylene-derived units, as measured by NMR, of 3.3 to 6.0 wt%; preferably 3.5 to 5.5 wt%, more preferably 3.7 to 4.8 wt%;

[0035] ii) a melting temperature as measured by DSC ranging from 132°C to 143°C; preferably ranging from 134°C to 142°C; more preferably ranging from 136°C to 141°C;

[0036] iii) melt flow rate (230°C / 2.16 kg. ISO 1133) ranging from 1.1 g / 10 min to 3.5 g / 10 min; preferably ranging from 1.2 g / 10 min to 2.5 g / 10 min; more preferably ranging from 1.3 g / 10 min to 2.0 g / 10 min;

[0037] iv) xylene solubles at 25°C ranging from 4.0 wt% to 10.0 wt%; preferably ranging from 4.5 wt% to 9.0 wt%; more preferably ranging from 5.2 wt% to 8.0 wt%;

[0038] B) 12 to 30 wt%, preferably 13 to 28 wt%, more preferably 14 to 27 wt% of a propylene ethylene copolymer containing 3.5 to 7.5 wt%, preferably 3.8 to 7.0 wt%, more preferably 4.0 to 6.8 wt% of ethylene-derived units as measured by NMR, and having a melt flow rate (230°C / 2.16 kg, ISO 1133) in the range of from 0.6 to 10 g / 10 min; preferably in the range of from 0.8 to 9 g / 10 min; more preferably in the range of from 2.0 to 8.5 g / 10 min

[0039] The obtained polyolefin composition has:

[0040] i) a content of ethylene-derived units as measured by NMR of 3.5 to 5.5 wt%; preferably 3.8 to 5.3 wt%; more preferably 3.9 to 5.0 wt%;

[0041] ii) the content of ethylene-derived units in the fraction soluble in xylene at 25° C., measured by NMR, is from 15.2% to 23.2% by weight; preferably from 16.3% to 22.2% by weight; more preferably from 17.2% to 21.3% by weight;

[0042] iii) melt flow rate (ISO 1133 (230°C, 2.16 kg) ranging from 1.0 g / 10 min to 4.0 g / 10 min; preferably ranging from 1.1 g / 10 min to 2.9 g / 10 min; more preferably ranging from 1.2 g / 10 min to 2.5 g / 10 min;

[0043] iv) xylene solubles at 25°C ranging from 5.1 wt% to 12.0 wt%; preferably ranging from 5.5 wt% to 11.0 wt%; more preferably ranging from 6.0 wt% to 10.0 wt%;

[0044] v) the intrinsic viscosity of the fraction soluble in xylene at 25°C, measured in tetralin at 135°C, ranges from 0.6 dl / g to 2.5 dl / g; preferably ranges from 0.8 dl / g to 2.0 dl / g; more preferably ranges from 1.0 dl / g to 1.8 dl / g;

[0045] vi) the difference between the content of ethylene-derived units of component B and the content of ethylene-derived units of component B (C2B-C2A) ranges from 0.3 to 5.0 wt%; preferably ranges from 0.4 to 4.0 wt%; more preferably ranges from 0.4 to 3.0 wt%;

[0046] The sum of A+B is 100.

[0047] The term copolymer necessarily refers to a binary copolymer containing two monomers (propylene and ethylene).

[0048] The polyolefin composition preferably has one or more of the following characteristics:

[0049] i) a haze measured on a 1 mm plate according to the method disclosed in the Examples ranging from 20.0% to 26.0%; preferably ranging from 21.0% to 25.0%; more preferably ranging from 22.0% to 24.5%;

[0050] ii) a flexural modulus (ASTM D 790) ranging from 500 MPa to 770 MPa; preferably from 550 MPa to 740 MPa; even more preferably from 600 MPa to 720 MPa;

[0051] iii) Charpy impact strength (ISO 179-1:2010) at 23°C ranges from 8.0 kJ / m 2 Up to 20.0 kj / m 2 ; preferably in the range of 10.0kj / m 2 Up to 18.0 kj / m 2 More preferably, the range is from 10.5 kj / m 2 Up to 17.0 kj / m 2 ;

[0052] iv) The ratio of flexural modulus to haze, F / H, ranges from 25.0 to 31.0; preferably, from 25.5 to 30.0; more preferably, from 26.0 to 29.0. A higher ratio means that the flexural modulus is too high and the composition is not soft enough, whereas a lower ratio means that the haze is too high and the material does not have good optical properties.

[0053] The polyolefin composition of the present invention is particularly suitable for obtaining small blow-molded articles, such as bottles.

[0054] Another object of the present invention is therefore a bottle comprising the composition according to the invention.

[0055] Small blow molded articles can be manufactured by various industrial processes known in the art.

[0056] The composition of the present invention can be prepared by blending components A) and B).

[0057] The polymerizations of A) and B) can be carried out in the presence of a Ziegler-Natta catalyst. An essential component of the catalyst is a solid catalyst component comprising a titanium compound having at least one titanium-halogen bond and an electron donor compound, both of which are supported in active form on a magnesium halide. Another essential component (cocatalyst) is an organoaluminum compound, such as an alkylaluminum compound.

[0058] An external donor is optionally added.

[0059] The catalysts typically used in the process of the present invention are capable of producing polypropylene having a xylene insolubility value at ambient temperature greater than 90%, preferably greater than 95%.

[0060] Catalysts having the above characteristics are well known in the patent literature; particularly advantageous are the catalysts described in US Patent 4,399,054 and European Patent 45977. Further examples can be found in US Patent 4,472,524.

[0061] The solid catalyst component used in the catalyst comprises as electron donor (internal donor) a compound selected from the group consisting of ethers, ketones, lactones, compounds containing N, P and / or S atoms, and esters of mono- and dicarboxylic acids.

[0062] Particularly suitable electron donor compounds are esters of phthalic acid and 1,3-diethers of the formula:

[0063]

[0064] where R I and R II Same or different and C1-C 18 Alkyl, C3-C 18 Cycloalkyl or C7-C 18 Aryl radical; R III and R IV are identical or different and are C1-C4 alkyl radicals; or are 1,3-diethers, wherein the carbon atom in position 2 belongs to a cyclic or polycyclic structure consisting of 5, 6 or 7 carbon atoms or 5-n or 6-n' carbon atoms and n nitrogen atoms and n' heteroatoms selected from the group consisting of N, O, S and Si, wherein n is 1 or 2 and n' is 1, 2 or 3, said structure containing two or three degrees of unsaturation (cyclopolyene structure) and optionally condensed with other cyclic structures or substituted by one or more substituents selected from the group consisting of linear or branched alkyl radicals, cycloalkyl radicals, aryl, aralkyl, alkaryl radicals and halogen, or condensed with other cyclic structures and substituted by one or more of the above substituents, one or more of which may also be bonded to the condensed cyclic structure; one or more of the above alkyl, cycloalkyl, aryl, aralkyl or alkaryl radicals and a condensed cyclic structure optionally containing one or more heteroatoms as substituents for carbon atoms or hydrogen atoms or both.

[0065] Ethers of this type are described in published European patent applications 361493 and 728769.

[0066] Representative examples of the diethers are 2-methyl-2-isopropyl-1,3-dimethoxypropane, 2,2-diisobutyl-1,3-dimethoxypropane, 2-isopropyl-2-cyclopentyl-1,3-dimethoxypropane, 2-isopropyl-2-isopentyl-1,3-dimethoxypropane, and 9,9-bis(methoxymethyl)fluorene.

[0067] Other suitable electron donor compounds are phthalic acid esters, such as diisobutyl phthalate, dioctyl phthalate, diphenyl phthalate and benzylbutyl phthalate.

[0068] The preparation of the above-mentioned catalyst components is carried out according to various methods.

[0069] For example, MgCl2.nROH adduct (especially in the form of spherical particles) (where n is typically from 1 to 3 and ROH is ethanol, butanol or isobutanol) is reacted with an excess of TiCl4 containing an electron donor compound. The reaction temperature is typically from 80°C to 120°C. The solid is then separated and reacted once more with TiCl4 in the presence or absence of the electron donor compound, after which it is separated and washed with an aliquot of a hydrocarbon until all chloride ions are gone.

[0070] In the solid catalyst component, the titanium compound, denoted Ti, is generally present in an amount of 0.5 to 10% by weight. The amount of electron donor compound remaining fixed on the solid catalyst component is generally 5 to 20 mol% relative to the magnesium dihalide.

[0071] Titanium compounds which can be used for the preparation of the solid catalyst component are titanium halides and halogen alcoholates. Titanium tetrachloride is the preferred compound.

[0072] The above reaction forms magnesium halides in active form. Other reactions are known in the literature which, starting from magnesium compounds other than halides, such as magnesium carboxylates, form magnesium halides in active form.

[0073] Al-alkyl compounds used as cocatalysts include Al-trialkyl groups such as Al-triethyl, Al-triisobutyl, Al-tri-n-butyl and linear or cyclic Al-alkyl compounds containing two or more Al atoms bonded to each other via O or N atoms or SO4 or SO3 groups.

[0074] The Al-alkyl compound is generally used in such an amount that the Al / Ti ratio is from 1 to 1000.

[0075] Electron donor compounds that can be used as external donors include aromatic acid esters, such as alkyl benzoates, and in particular silicon compounds containing at least one Si-OR bond, where R is a hydrocarbon radical.

[0076] Examples of silicon compounds are (tert-butyl)2Si(OCH3)2, (cyclohexyl)(methyl)Si(OCH3)2, (cyclopentyl)2Si(OCH3)2 and (phenyl)2Si(OCH3)2 and (1,1,2-trimethylpropyl)Si(OCH3)3.

[0077] 1,3-Diethers of the above-mentioned formula can also be used advantageously. If the internal donor is one of these diethers, the external donor can be omitted.

[0078] In particular, component A) is preferably prepared by using a catalyst containing a phthalate as internal donor and (cyclopentyl)2Si(OCH3)2 as external donor, or the 1,3-diether as internal donor, even though many other combinations of the aforementioned catalyst components may allow the compositions according to the invention to be obtained.

[0079] The Ziegler-Natta catalyst that can be used to prepare the propylene polymers of the present invention is a solid catalyst component comprising a magnesium halide, a titanium compound having at least one titanium-halogen bond as described above and at least two electron donor compounds, one of which is selected from succinates and the other is selected from 1,3-diethers.

[0080] Component B) can be prepared by using the above-mentioned catalyst system or by using a metallocene-based catalyst system.Component B) can be obtained by using a gas phase polymerization process, a slurry polymerization process or a solution polymerization process.

[0081] It is also possible to prepare components (A) and (B) in a continuous sequential polymerization process, wherein component A) is prepared in a first reactor and component (B) is prepared in a second reactor in the presence of component A) according to known techniques and operating in the gas phase or in the liquid phase with or without an inert diluent, or by mixed liquid-gas techniques.

[0082] The following examples are given for illustration of the present invention and not for limiting purposes.

[0083] Examples

[0084] Characterization methods

[0085] Melting temperature and crystallization temperature: determined by differential scanning calorimetry (DSC)

[0086] Weigh 6 ± 1 mg of sample and heat to 220 ± 1°C at a rate of 20°C / min in a nitrogen stream. Hold at 220 ± 1°C for 2 minutes. Then cool to 40 ± 2°C at a rate of 20°C / min and hold at this temperature for 2 minutes to allow the sample to crystallize. Then, heat to 220 ± 1°C at a rate of 20°C / min to allow the sample to melt again. Record a melting scan to obtain a thermogram, from which the melting and crystallization temperatures are read.

[0087] Melt flow rate: measured according to method ISO 1133 (230° C., 2.16 kg).

[0088] Xylene soluble fraction at 25°C (XS)

[0089] The xylene solubles at 25°C have been determined according to ISO 16152:2005; the solution volume is 250 ml, the solution is settled at 25°C for 20 minutes, with 10 minutes of stirring (magnetic stirrer), and dried at 70°C.

[0090] Intrinsic viscosity (IV)

[0091] The sample was dissolved in tetralin at 135°C and then poured into a capillary viscometer.

[0092] The viscometer tube (Ubbelohde type) is surrounded by a cylindrical glass jacket; this setup allows temperature control with a circulating thermostatic liquid.

[0093] The downward passage of the meniscus is timed by a photoelectric device. The meniscus's passage in front of the upper lamp starts a counter with a quartz crystal oscillator. When it passes the lower lamp, the meniscus stops the counter and the outflow time is recorded: this is converted to an intrinsic viscosity value by the following method

[0094] Haze (on 1mm plate)

[0095] Depending on the method used, 5 x 5 cm specimens were cut into 1 mm thick molded plaques and the haze values ​​were measured using a Gardner photometer connected to a UX-10 hazemeter or equivalent instrument with a GE1209 light source and filter "C." Reference samples of known haze were used to calibrate the instrument. The plaques to be tested were produced according to the following method.

[0096] Plaques measuring 75 x 75 x 1 mm were molded using a 90 ton GBF Plastiniector G235190 injection molding machine under the following processing conditions:

[0097] Screw speed: 120rpm

[0098] Back pressure: 10 bar

[0099] Melting temperature: 260℃

[0100] Injection time: 5 seconds

[0101] Switch to holding pressure: 50 bar

[0102] First stage holding pressure: 30 bar

[0103] Second stage pressure: 20 bar

[0104] Maintain pressure curve: 5 seconds in the first stage

[0105] Second stage 10 seconds

[0106] Cooldown: 20 seconds

[0107] Mold water temperature: 40℃

[0108] Ethylene content in copolymer

[0109] The data were collected on a Bruker AV-600 spectrometer equipped with a cryoprobe. 13 C NMR spectroscopy, operated in Fourier transform mode at 160.91 MHz at 120 °C.

[0110] Sββ carbon (according to "through 13 3. Use of the reaction probability model (Monomer Sequence Distribution in Ethylene-Propylene Rubber Measured by C NMR 13 C NMR.3. Use of Reaction Probability Mode (Nomenclature)" CJ Carman, RA Harrington and CE Wilkes, Macromolecules, 1977, vol. 10, p. 536) peak was used as an internal reference with a value of 29.9 ppm. The sample was dissolved in 1,1,2,2-tetrachloroethane-d2 at 120°C at a concentration of 8% wt / v. Each spectrum was acquired with a 90° pulse with a 15 s delay between the pulse and the CPD to eliminate 1 H- 13 C coupling. 512 transient data were stored in 32K data points using a 9000 Hz spectral window.

[0111] According to Kakugo ("Carbon-13 NMR determination of monomer sequence distribution in ethylene-propylene copolymers prepared with δ-titanium trichloride-diethyl-aluminum chloride", M. Kakugo, Y. Naito, K. Mizunuma and T. Miyatake, Macromolecules, 1982, Vol. 15, p. 1150), the spectra were assigned using the following equations, and the triad distribution and composition were evaluated:

[0112] PPP=100Tββ / S PPE=100Tβδ / S EPE=100Tδδ / S

[0113] PEP=100Sββ / S PEE=100Sβδ / S EEE=100(0.25Sγδ+0.5Sδδ) / S

[0114] S=Tββ+Tβδ+Tδδ+Sββ+Sβδ+0.25Sγδ+0.5Sδδ

[0115] The mole percentage of ethylene content was estimated using the following equation:

[0116] E% mol = 100*[PEP+PEE+EEE]. The weight percentage of ethylene content was estimated using the following equation:

[0117] 100*E%mol*MWE

[0118] E%wt.=E%mol*MWE+P%mol*MWP

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

[0120] The product of the reactivity ratios r1 and r2 was calculated according to Carman (CJ Carman, RA Harrington and CE Wilkes, Macromolecules, 1977; Vol. 10, p. 536) as follows:

[0121]

[0122] The tacticity of the propylene sequences was calculated as mm content from the ratio of PPP mm Tββ (28.90 to 29.65 ppm) to total Tββ (29.80 to 28.37 ppm).

[0123] Impact test: ISO 180

[0124] Preparation of injection molded specimens: Specimens of 80×10×4 mm were obtained according to method ISO 1873-2:2007.

[0125] Preparation of injection molded specimens: Specimens of 80×10×4 mm were obtained according to method ISO 1873-2:2007.

[0126] Charpy impact test at 23°C: measured on injection molded specimens according to ISO 179-1:2010.

[0127] Example 1 according to the present invention

[0128] Catalyst system

[0129] The Ziegler-Natta catalyst was prepared according to Example 5, lines 48 to 55 of European Patent EP728769. Triethylaluminum (TEAL) was used as a cocatalyst and dicyclopentyldimethoxysilane (DCPMS) was used as an external donor in the weight ratios shown in Table 1.

[0130] Prepolymerization treatment

[0131] Before the solid catalyst component is introduced into the polymerization reactor, it is suspended in liquid propylene at 20°C for about 5 minutes and then introduced into the first polymerization reactor for prepolymerization.

[0132] polymerization

[0133] The polymerization experiments were carried out in a continuous mode in a series of three reactors equipped with a device to transfer the product from one reactor to another reactor immediately adjacent thereto. The first two reactors were liquid phase reactors, and the third was a fluidized bed gas phase reactor. Component (A) was produced in the first and second reactors, while component (B) was produced in the third reactor.

[0134] Hydrogen was used as a molecular weight regulator.

[0135] The gas phase (propylene, ethylene and hydrogen) was analyzed continuously by gas chromatography.

[0136] At the end of the experiment, the powder was discharged and dried under a stream of nitrogen.

[0137] The main polymerization conditions are reported in Table 1.

[0138] Table 1

[0139]

[0140]

[0141] C2 = ethylene; C3 = propylene; H2 = hydrogen

[0142] Table 2 reports the characteristics of the compositions of Examples 1 to 3 and Comparative Example 4.

[0143] Examples Example 1 Example 2 Example 3 Comparative Example 4 Component A) Ethylene content weight% 4.0 4.3 4.3 2.6 MFR g / 10' 1.5 1.5 1.6 5 Xylene soluble matter at 25°C weight% 6.0 7.2 6.4 - Melting temperature ℃ 139 137.8 137.5 - Component B) Splinters weight% 18 22 22 59.8 Ethylene content in component b)* weight% 4.6 5.7 6.1 6.6 MFR* g / 10' 2.55 2.65 7.24 0.66 Characteristics of the composition Xylene soluble matter at 25°C weight% 6.8 8.3 9.0 - MFR g / 10' 1.56 1.71 2.23 1.9 XSIV (XS intrinsic viscosity) dl / g 1.1 1.23 1.25 1.8 Ethylene content in the xylene soluble fraction weight% 18.8 18.2 17.9 17.6 Ethylene content weight% 4.1 4.6 4.7 5.0 flexural modulus MPa 710 660 630 792 Haze (1mm plate) ％ 23.9 23.2 23.5 20.1 Charpy impact strength at 23°C <![CDATA[Kj / m 2 ]]> 11.8 12.3 10.4 - FM / H ratio 29.7 28.4 26.8 39.4

[0144] *Comparative Example 4 calculated is Example P2 of WO 2020 / 148319

Claims

1. A polyolefin composition comprising: A) 70 to 90 wt. % of a copolymer of propylene and ethylene, wherein: i) a content of ethylene-derived units of from 3.3% to 6.0% by weight as measured by NMR; ii) a melting temperature ranging from 132° C. to 143° C. as measured by DSC; iii) melt flow rate, 230°C / 2.16 kg, ISO 1133, ranges from 1.1 g / 10 min to 3.5 g / 10 min; iv) a xylene soluble matter at 25°C ranging from 4.0 wt% to 10.0 wt%; B) 10 to 30 wt% of a propylene ethylene copolymer containing 3.6 to 7.5 wt% of ethylene-derived units as measured by NMR, with a melt flow rate, 230°C / 2.16 kg. ISO 1133, ranging from 0.6 to 10 g / 10 min; The obtained polyolefin composition has: i) a content of ethylene-derived units of 3.5 to 5.5 wt% as measured by NMR; ii) a content of ethylene-derived units in the xylene-soluble fraction at 25° C., measured by NMR, of from 15.2% to 23.2% by weight; iii) melt flow rate, 230°C / 2.16 kg, ISO 1133, ranges from 1.0 g / 10 min to 4.0 g / 10 min; iv) a xylene soluble matter at 25° C. ranging from 5.1 wt % to 12.0 wt %; v) the intrinsic viscosity of said fraction soluble in xylene at 25°C, measured in tetralin at 135°C, ranges from 0.6 dl / g to 2.5 dl / g; vi) the difference between the ethylene-derived unit content of component B and the ethylene-derived unit content of component A (C2B-C2A) ranges from 0.3 wt% to 5.0 wt%; The sum of A+B is 100.

2. The polyolefin composition according to claim 1, wherein the content of ethylene-derived units in component A) ranges from 3.5 wt.-% to 5.5 wt.-%.

3. The polyolefin composition according to claim 1, wherein in component A), the melt flow rate, 230°C / 2.16 kg, ISO 1133, ranges from 1.2 g / 10 min to 2.5 g / 10 min.

4. The polyolefin composition according to claim 1, wherein In component A), the xylene solubles at 25° C. range from 4.5 wt % to 9.0 wt %.

5. The polyolefin composition according to claim 1, wherein in component B), the ethylene-derived units content ranges from 3.8 wt% to 7.0 wt%.

6. The polyolefin composition according to claim 1, wherein the content of ethylene-derived units measured by NMR is from 3.8 wt% to 5.3 wt%.

7. The polyolefin composition according to claim 1, wherein the content of ethylene-derived units in the fraction soluble in xylene at 25°C measured by NMR is from 16.3 wt% to 22.2 wt%.

8. The polyolefin composition according to claim 1, wherein the melt flow rate of the obtained polyolefin composition, 230°C / 2.16 kg, ISO 1133, ranges from 1.1 g / 10 min to 2.9 g / 10 min.

9. The polyolefin composition according to claim 1, wherein the xylene solubles at 25°C range from 5.5 wt% to 11.0 wt%.

10. The polyolefin composition according to claim 1, wherein the intrinsic viscosity of the fraction soluble in xylene at 25°C, measured in tetralin at 135°C, ranges from 0.8 dl / g to 2.0 dl / g.

11. The polyolefin composition according to claim 1, wherein the difference (C2B-C2A) between the ethylene-derived unit content of component B and the ethylene-derived unit content of component A ranges from 0.4 wt% to 4.0 wt%.

12. The polyolefin composition according to claim 1, wherein in component B), the melt flow rate, 230°C / 2.16 kg. ISO 1133, ranges from 0.8 g / 10 min to 9.0 g / 10 min.

13. The polyolefin composition according to claim 1, wherein the content of ethylene-derived units in the fraction soluble in xylene at 25°C measured by NMR is from 17.2 wt% to 21.3 wt%.

14. A bottle comprising the polyolefin composition according to claim 1.

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