EA043459B1 - PRODUCT CONTAINING A FIBER REINFORCED POLYPROPYLENE COMPOSITION - Google Patents

Description

The present invention relates to an article containing a fiber-reinforced composition (C), said composition comprising a propylene polymer (PP), an elastomeric ethylene copolymer (E) and fibers (F).

The mechanical properties of fiber-reinforced polypropylene compositions, particularly stiffness and strength, are generally controlled by the fiber content. In particular, an increase in fiber content leads to an increase in stiffness and strength. The addition of fibers to the polypropylene composition also results in improved notch impact and puncture resistance. However, in such compositions, the impact behavior is completely controlled by the fiber content, making further improvement of the impact properties of fiber-reinforced polypropylene compositions very challenging.

The most obvious approach to impart toughness to a fiber-reinforced polypropylene composition is to add significant amounts of elastomeric components. The disadvantage of this approach is a significant reduction in stiffness and strength.

Accordingly, there continues to be a need for a fiber-reinforced polypropylene composition having excellent strength and high stiffness properties.

It is therefore an object of the present invention to provide a fiber-reinforced polypropylene composition having improved notch impact and puncture resistance without compromising tensile mechanical properties.

The discovery of the present invention provides an article containing a fiber-reinforced composition containing a small amount of elastomer.

Therefore, the present invention relates to an article containing a fiber-reinforced composition (C) comprising:

i) from 20.0 to 80.0 wt.% propylene polymer (PP), which is at least bimodal and has a melt flow rate MFR ₂ (230°C, 2.16 kg), as defined according to ISO 1133, in ranging from 30 to 250 g/10 min, ii) from 2.0 to 12.0 wt.% elastomeric ethylene copolymer (E) representing a copolymer of ethylene and C ₄ -C ₁₀ α-olefin, iii) from 0.1 to 5 .0 wt.% adhesion promoter (AP); and iv) from 10.0 to 70.0 wt.% fibers (F) based on the total weight of the fiber-reinforced composition (C).

According to another embodiment of the present invention, the fiber reinforced composition (C) has a melt flow rate MFR2 (230°C, 2.16 kg), as determined according to ISO 1133, less than 100.0 g/10 min.

According to another embodiment of the present invention, the adhesion promoter (AP) is a polar modified polypropylene (PM-PP) homo- or copolymer of maleic anhydride grafted propylene with a melt flow rate MFR (190°C, 2.16 kg) as determined according to ISO 1133, at least 50.0 g/10 min.

According to a further embodiment of the present invention, the fiber reinforced composition (C) contains a propylene polymer (PP) and an elastomeric ethylene copolymer (E) in a weight ratio of 85:15 to 99:1.

According to another embodiment of the present invention, the fiber-reinforced composition (C) contains fibers (F) and ethylene copolymer (E) in a weight ratio of 95:5 to 70:30.

According to one embodiment of the present invention, the elastomeric ethylene copolymer (E) has a melt flow rate MFR (190°C, 2.16 kg), as determined according to ISO 1133, of at least 25.0 g/10 min.

According to another embodiment of the present invention, the elastomeric ethylene copolymer (E) has:

a) comonomer content from 2.0 to 25.0 mol.% and/or

b) density less than 0.900 g/cm ³ .

As such, preferably the elastomeric ethylene copolymer (E) is a copolymer of ethylene and 1-octene.

According to one embodiment of the present invention, the propylene polymer (PP) is a propylene homopolymer.

According to another embodiment of the present invention, the fibers (F) are selected from the group consisting of glass fiber, metal fiber, ceramic fiber, carbon fiber and graphite fiber.

As such, preferably the fibers (F) are short fibers (SF) and/or long fibers (LF), preferably short glass fiber (SGF) and/or long glass fiber (LGF).

According to one embodiment of the present invention, the article contains at least 80.0% by weight of the fiber-reinforced composition (C) based on the total weight of the article.

According to another embodiment of the present invention, the product is a cast product.

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As such, preferably the product is an injection molded product. Hereinafter, the present invention will be described in more detail.

Fiber reinforced polypropylene composition (C).

As stated above, the present invention relates to an article containing a fiber-reinforced polypropylene composition (C).

According to a preferred embodiment of the present invention, the granules contain at least 80.0 wt.%, more preferably at least 90.0 wt.%, even more preferably at least 95.0 wt.%, such as at least 99 .0 wt.% of the fiber-reinforced polypropylene composition (C) of the total weight of the product. As such, preferably the article consists of a fiber-reinforced composition (C).

Preferably the product is a molded product, more preferably an injection molded product.

As such, the product is preferably an injection molded product for the automotive industry.

In one substantially preferred embodiment of the present invention, the article relates to an injection molded article, such as an automotive injection molded article, consisting of a fiber reinforced polypropylene composition (C) as defined above.

As stated above, said fiber-reinforced polypropylene composition (C) contains a propylene polymer (PP), an elastomeric ethylene copolymer (E), an adhesion promoter (AP) and fibers (F). In one preferred embodiment of the present invention, propylene polymer (PP), ethylene elastomeric copolymer (E), adhesion promoter (AP) and fibers (F) constitute the bulk of the fiber-reinforced polypropylene composition (C). That is, in one preferred embodiment of the present invention, the fiber reinforced polypropylene composition (C) contains a propylene polymer (PP), an elastomeric ethylene copolymer (E), an adhesion promoter (AP) and fibers (F), wherein the propylene polymer (PP), an elastomeric copolymer ethylene (E) and adhesion promoter (AP) are the main polymer components in the fiber-reinforced polypropylene composition (C), that is, the fiber-reinforced polypropylene composition (C) contains no more than 10 wt.%, preferably no more than 5 wt.%, of the total fiber-reinforced composition of polypropylene (C), polymers other than propylene polymer (PP), ethylene elastomeric copolymer (E) and adhesion promoter (AP). Such additional polymers can be, for example, additive carrier polymers (AD). Accordingly, in one specific embodiment of the present invention, the fiber reinforced polypropylene composition (C) consists of propylene polymer (PP), elastomeric propylene copolymer (E), adhesion promoter (AP), long fibers (LF) and additives (AD), including polymer carriers.

The fiber reinforced composition (C) contains the elastomeric ethylene copolymer (E) in sufficiently small quantities to achieve a good balance of stiffness and strength properties.

Accordingly, the fiber-reinforced composition (C) contains:

i) from 20.0 to 80.0 wt.%, more preferably from 28.0 to 78.0 wt.%, even more preferably from 33.0 to 76.0 wt.% propylene polymer (PP), ii) from 2.0 to 12.0 wt.%, more preferably from 2.2 to 11.0 wt.%, even more preferably 2.5 to 10.0 wt.% ethylene elastomeric copolymer (E), iii) from 0 1 to 5.0 wt%, more preferably 1.0 to 3.0 wt%, even more preferably 1.5 to 2.0 wt% adhesion promoter (AP), and iv) from 10.0 up to 70.0 wt.%, more preferably from 15.0 to 60.0 wt.%, even more preferably from 20.0 to 50.0 wt.% fibers (F) based on the total weight of the fiber-reinforced composition (C).

Therefore, preferably the fiber reinforced composition (C) contains a propylene polymer (PP) and an elastomeric ethylene copolymer (E) preferably in a weight ratio of 87:13 to 97:3, even more preferably in a weight ratio of 90:10 to 95:5.

Additionally or as an alternative to the preceding paragraph, preferably the fiber-reinforced composition (C) contains fibers (F) and ethylene copolymer (E) in a weight ratio of 95:5 to 70:30, more preferably in a weight ratio of 93:7 to 80: 20, even more preferably in a mass ratio of 91:9 to 98:11.

As stated above, the fiber reinforced polypropylene composition (C) may include additives (AD).

Accordingly, preferably the fiber reinforced polypropylene composition (C) contains, more preferably consists of, from 20.0 to 80.0 wt.%, more preferably from 28.0 to 78.0 wt.%, even more preferably from 33.0 up to 76.0 wt.% propylene polymer (PP), from 2.0 to 12.0 wt.%, more preferably from 2.2 to 11.0 wt.%, even more preferably from 2.5 to 10.0 wt.% elastomeric copolymer of ethylene (E), from 0.1 to 5.0 wt.%, more preferably from 1.0 to 3.0 wt.%, even more preferably from 1.5 to 2.0 wt.% adhesion promoter (AP), from 10.0 to 70.0 wt.%, more preferably from 15.0 to 60.0 wt.%, even more preferably from 20.0 to 50.0 wt.% fiber (F) And

- 2 043459 optionally from 0.05 to 5.0 wt.%, more preferably from 0.1 to 4.0 wt.%, even more preferably from 1.0 to 3.0 wt.% additives (AD) of the total mass of the fiber-reinforced composition (C). Additives (AD) are described in more detail below.

According to one preferred embodiment of the present invention, the propylene polymer (PP) is at least bimodal. In particular, preferably the propylene polymer (PP) contains three fractions of propylene polymer, that is, a first propylene polymer (PP1), a second propylene polymer (PP2) and a third propylene polymer (PP3), having different melt flow rates. These propylene polymer fractions (PP1), (PP2) and (PP3) are described in more detail below.

Preferably, the fiber reinforced polypropylene composition (C) contains, more preferably consists of from 5.0 to 40.0 wt%, more preferably from 7.0 to 38.0 wt%, even more preferably from 7.5 to 35, 0 wt.% of the first propylene polymer (PP1), from 15.0 to 40.0 wt.%, more preferably from 18.0 to 38.0 wt.%, even more preferably from 19.0 to 35.0 wt. % second propylene polymer (PP2), from 4.0 to 15.0 wt.%, more preferably from 5.0 to 10.0 wt.%, even more preferably from 6.0 to 9.0 wt.% third propylene polymer (PP3), from 2.0 to 12.0 wt.%, more preferably from 2.2 to 11.0 wt.%, even more preferably from 2.5 to 10.0 wt.% ethylene elastomeric copolymer (E ), from 0.1 to 5.0 wt.%, more preferably from 1.0 to 3.0 wt.%, even more preferably from 1.5 to 2.0 wt.% adhesion promoter (AP), from 10, 0 to 70.0 wt.%, more preferably from 15.0 to 60.0 wt.%, even more preferably from 20.0 to 50.0 wt.% fiber (F) and optionally from 0.05 to 5, 0 wt.%, more preferably from 0.1 to 4.0 wt.%, even more preferably from 1.0 to 3.0 wt.% additives (AD) based on the total weight of the fiber reinforced composition (C).

Preferably, the fiber reinforced polypropylene composition (C) has a melt flow rate MFR ₂ (230°C, 2.16 kg), as determined according to ISO 1133, less than 100.0 g/10 min, more preferably in the range from 0.1 to 90 .0 g/10 min, even more preferably in the range from 1.0 to 30.0 g/10 min, even more preferably in the range from 1.5 to 20.0 g/10 min, such as in the range from 2. 0 to 10.0 g/10 min.

As stated above, it is understood that the fiber reinforced polypropylene composition (C) of the present invention is a fairly rigid material. Accordingly, preferably the fiber reinforced polypropylene composition (C) has a tensile modulus, as determined according to ISO 527, of at least 4000 MPa, more preferably in the range of 4000 to 20000 MPa, even more preferably in the range of 4500 to 17000 MPa, such as in the range from 5000 to 12500 MPa.

Additionally, the preferably fiber-reinforced polypropylene composition (C) of the present invention is characterized by improved impact resistance. Therefore, preferably the fiber reinforced polypropylene composition (C) has a puncture energy, as determined according to ISO 6603, of at least 8.0 J, more preferably at least 8.5 J, even more preferably at least 9.0 J.

Additionally or alternatively, preferably the fiber reinforced polypropylene composition (C) has a Charpy notched impact strength, as determined according to ISO 179/1eA at 23°C, of at least 5.0 kJ/m ² , more preferably at least 10, kJ/m ² , even more preferably at least 12.0 kg/m ² and/or Charpy unnotched impact strength, as determined according to ISO 179/leU at 23°C, at least 40.0 kg/ ^m2 , more preferably at least 50.0 kg/ ^m2 , even more preferably at least 60.0 kg/ ^m2 .

According to one embodiment of the present invention, a preferably fiber-reinforced polypropylene composition (C) is prepared by melt blending a propylene polymer (PP), an elastomeric ethylene copolymer (E), an adhesion promoter (AD), a fiber (F), and optionally an additive in the above-mentioned by weight ratio.

For melt blending, traditional compounding or mixing devices such as a Banbury mixer, 2-roller resin mixer, Buss koknider or twin-screw extruder can be used. The polymer materials released from the extruder/mixer are usually in the form of granules. These granules are then preferably further processed, for example by injection molding, to produce articles and products of the composition of the present invention.

As such, the preferably fiber-reinforced composition (C) of the present invention is prepared by melt mixing the individual components in an extruder, preferably a twin-screw extruder.

Particularly, preferably, the fiber-reinforced composition (C) of the present invention is produced by using a method comprising the steps of:

(a) feeding propylene polymer (PP), ethylene elastomeric copolymer (E), adhesion promoter (AP) and optional additives (AD) into an extruder, preferably a twin-screw extruder, (b) melt mixing the composition obtained in step (a), at a temperature of from 200 to 270°C, (c) feeding the fiber (F) into an extruder, preferably a twin-screw extruder, containing the composition obtained in step (b),

- 3 043459 (d) melt mixing the composition obtained in step (c) at a temperature of from 200 to

270°C, thereby obtaining a fiber-reinforced composition (C), and (e) optionally processing the fiber-reinforced composition (C) obtained in step (d) into granules.

According to one embodiment of the present invention, preferably the fibers (F) are short fibers (SF), as described in more detail below.

According to another embodiment of the present invention, the fiber-reinforced composition (C) is obtained using a method comprising the steps of:

(a') contacting the fibers (F) with a molten first fraction of propylene polymer (PP) and an adhesion promoter (AP), thereby obtaining impregnated fibers, (b') contacting the impregnated fibers obtained in step a) with the molten a second fraction of propylene polymer (PP) and an elastomeric ethylene copolymer (E), thereby obtaining a fiber-reinforced polypropylene strand, and (c') cutting the fiber-reinforced polypropylene strand obtained in step b) into pellets.

According to one embodiment of the present invention, preferably the fibers (F) are long fibers (LF), as described in more detail below.

The article of the present invention is preferably produced using mold casting, preferably injection molding, from granules obtained in step (d) or (c').

The propylene polymer (PP), elastomeric propylene copolymer (E), adhesion promoter and fibers (F) will now be described in more detail.

Propylene polymer (PP).

As stated above, the fiber reinforced polypropylene composition (C) contains a propylene polymer (PP).

The propylene polymer (PP) may be a propylene copolymer or a propylene homopolymer, the latter being substantially preferred.

In the case where the propylene polymer (PP) is a copolymer of propylene, the propylene polymer (PP) contains monomers copolymerizable with propylene, for example comonomers such as ethylene and/or C ₄ -C ₈ α-olefins, in particular ethylene and/or C ₄ -C ₆ α-olefins, for example 1-butene and/or 1 hexene. Preferably, the propylene polymer (PP) of the present invention contains, in particular consists of, propylene-copolymerizable monomers from the group consisting of ethylene, 1-butene and 1-hexene. More preferably, the propylene polymer (PP) of the present invention contains units derived from ethylene and/or 1-butene in addition to propylene. In one preferred embodiment, the propylene polymer (PP) contains units derived only from ethylene and propylene.

The propylene polymer (PP) comonomer content is in the range of 0.0 to 5.0 mol%, even more preferably in the range of 0.0 to 3.0 mol%, even more preferably in the range of 0.0 to 1 .0 mol.%.

As such, preferably the propylene polymer (PP) is a propylene homopolymer (H-PP).

As used herein, the term propylene homopolymer refers to polypropylene which is substantially, that is, greater than 99.7% by weight, even more preferably at least 99.8% by weight, such as at least 99.9 wt.%, from propylene units. In a preferred embodiment of the present invention, only propylene units, that is, only polymerized propylene, are detected in the propylene homopolymer.

Preferably, the propylene polymer (PP), such as propylene homopolymer (H-PP), is isotactic. Accordingly, preferably the propylene polymer (PP), such as propylene homopolymer (H-PP), has a fairly high pentad concentration (mmmm%) i.e. greater than 94.1%, more preferably greater than 94.4%, such as greater than rather than 94.4 to 98.5%, even more preferably at least 94.7%, such as in the range of 94.7 to 97.5%.

Preferably, the propylene polymer (PP), such as propylene homopolymer (H-PP), is characterized by a fairly low xylene cold soluble fraction (XCS) content, that is, a xylene cold soluble fraction (XCS) content of less than 3.1 wt. % Accordingly, the propylene polymer (PP), such as propylene homopolymer (H-PP), preferably has a xylene cold soluble fraction (XCS) content in the range of 1.0 to 3.0 wt.%, more preferably in the range from 1.5 to 2.8 wt.%, even more preferably in the range from 2.0 to 2.6 wt.%.

The amount of cold xylene soluble fraction (XCS) further indicates that the propylene polymer (PP), such as propylene homopolymer (H-PP), is preferably free of any elastomeric polymer component, such as ethylene-propylene rubber . In other words, a propylene polymer (PP), such as a propylene homopolymer (H-PP), does not have to be a heterophasic polypropylene, that is, a system consisting of a polypropylene matrix in which an elastomeric phase is dispersed. Such systems are characterized by a fairly high content of the fraction soluble in cold xylene.

The amount of cold xylene soluble fraction (XCS) further indicates that the propylene polymer (PP), such as propylene homopolymer (H-PP), preferably does not contain inclusion-forming elastomeric (co)polymers as a second phase for improvement of mechanical properties. A polymer containing elastomeric (co)polymers, since second phase inserts will instead be referred to as heterophasic, and are preferably not part of the present invention. The presence of second phases or so-called inclusions can be seen using, for example, high-resolution microscopy such as electron microscopy or atomic force microscopy, or dynamic mechanical thermal analysis (DMTA). In particular, when using DMTA, the presence of a multiphase structure can be determined by the presence of at least two different glass transition temperatures.

Accordingly, preferably the propylene polymer (PP), such as the propylene homopolymer (H-PP), of the present invention does not have a glass transition temperature below -30°C, preferably below -25°C, more preferably below -20°C.

On the other hand, in one preferred embodiment of the present invention, the propylene polymer (PP), such as propylene homopolymer (H-PP), of the present invention has a glass transition temperature in the range of -12 to 5°C, more preferably in the range of -10 up to 4°C.

Additionally, the propylene polymer (PP), such as propylene homopolymer (H-PP), is preferably crystalline. As used herein, the term crystalline indicates that the propylene polymer (PP), such as propylene homopolymer (H-PP), has a sufficiently high melting point. Accordingly, a propylene polymer (PP), such as a propylene homopolymer (H-PP) described in the specification of this patent application, is crystalline unless clearly stated otherwise. Therefore, the propylene polymer (PP), such as propylene homopolymer (H-PP), preferably has a melting point Tm, measured using differential scanning calorimetry (DSC), of at least 160°C, even more preferably at least 161°C , even more preferably at least 163°C, such as in the range from 163°C to 167°C.

Additionally, preferably the propylene polymer (PP), such as propylene homopolymer (H-PP), has a crystallization temperature Tg, measured using differential scanning calorimetry (DSC), equal to or greater than 108° C., more preferably in the range of 110 to 130° C, more preferably in the range from 112 to 126°C.

It is clear that propylene polymer (PP) is characterized by a moderate melt flow rate. Accordingly, the propylene polymer (PP) has a melt flow rate MFR ₂ (230°C, 2.16 kg), as defined according to ISO 1133, in the range of 20 to 250 g/10 min, preferably in the range of 30 to 250 g/10 min, more preferably in the range from 50 to 150 g/10 min, even more preferably in the range from 60 to 120 g/10 min, such as in the range from 60 to 80 g/10 min.

As stated above, the propylene polymer (PP) is at least bimodal.

Accordingly, the propylene polymer (PP) contains at least two, such as three fractions of propylene polymer. Essentially, preferably, the propylene polymer (PP) contains three fractions of propylene polymer, that is, a first propylene polymer (PP1), a second propylene polymer (PP2) and a third propylene polymer (PP3).

Preferably, the first propylene polymer (PP1), the second propylene polymer (PP2) and the third propylene polymer (PP3) have different melt flow rates MFR2 (230°C, 2.16 kg) as determined according to ISO 1133.

Additionally or as an alternative to the preceding paragraph, preferably the propylene polymer (PP) contains:

i) from 10.0 to 55.0 wt.%, more preferably from 15.0 to 50.0 wt.%, even more preferably from 20.0 to 46.0 wt.% of the first propylene polymer (PP1), ii ) from 30.0 to 55.0 wt.%, more preferably from 40.0 to 50.0 wt.%, even more preferably from 42.0 to 46.0 wt.% of the second propylene polymer (PP2), and iii ) from 5.0 to 35.0 wt.%, more preferably from 7.0 to 30.0 wt.%, even more preferably from 9.0 to 25.0 wt.% of the third propylene polymer (PP3) based on the total weight propylene polymer (PP).

The first propylene polymer (PP1), the second propylene polymer (PP2), and the third propylene polymer (PP3) may be propylene copolymers or propylene homopolymers, respectively.

In the case where the first propylene polymer (PP1), the second propylene polymer (PP2) and/or the third propylene polymer (PP3) are copolymers of propylene, said propylene polymers contain monomers copolymerizable with propylene, for example comonomers such as ethylene and/or C ₄ -C ₈ α-olefins, in particular ethylene and/or C ₄ -C ₆ α-olefins, for example 1-butene and/or 1hexene. Preferably, the first propylene polymer (PP1), the second propylene polymer (PP2) and/or the third propylene polymer (PP3) of the present invention contains, in particular consists of monomers copolymerizable with propylene, from the group consisting of ethylene, 1-butene and 1 -hexene.

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More preferably, the first propylene polymer (PP1), the second propylene polymer (PP2) and/or the third propylene polymer (PP3) of the present invention contains units derived from ethylene and/or 1-butene in addition to propylene. In one preferred embodiment of the present invention, the propylene polymer (PP) contains units derived only from ethylene and propylene.

The comonomer content of the first propylene polymer (PP1), the second propylene polymer (PP2) and/or the third propylene polymer (PP3) is in the range from 0.0 to 5.0 mol.%, even more preferably in the range from 0.0 to 3 .0 mol.%, even more preferably in the range from 0.0 to 1.0 mol.%, respectively.

However, as stated above, preferably the propylene polymer (PP) is a propylene homopolymer (H-PP). Therefore, preferably, all propylene polymer (PP) fractions, ie the first propylene polymer (PP1), the second propylene polymer (PP2) and the third propylene polymer (PP3), were propylene homopolymers. With respect to the term propylene homopolymer as used herein, reference is made to the above definition.

Next, the first propylene polymer (PP1), the second propylene polymer (PP2), and the third propylene polymer (PP3) will be described in more detail.

The first propylene polymer (PP1).

The first propylene polymer (PP1) is preferably a high melt flow propylene polymer. Therefore, preferably the first propylene polymer (PP1) has a melt flow rate MFR2 (230°C, 2.16 kg), as determined according to ISO 1133, of at least 100 g/10 min, more preferably in the range from 100 to 800 g/ 10 min, even more preferably in the range from 200 to 500 g/10 min, even more preferably in the range from 300 to 490 g/10 min, such as in the range from 400 to 480 g/10 min.

In this regard, preferably the first propylene polymer (PP1) has undergone visbreaking. Unless otherwise stated in the specification of this patent application, the melt flow rate MFR2 (230°C/2.16 kg) of the first propylene polymer (PP1) preferably represents the melt flow rate (230°C/2.16 kg) after visbreaking .

Accordingly, the melt flow rate MFR ₂ (initial) (230°C/2.16 kg), that is, the melt flow rate before visbreaking, of the first propylene polymer (PP1) is significantly lower, such as from 15 to 150 g/10 min. For example, the melt flow rate MFR2 (initial) (230°C/2.16 kg) of the first propylene polymer (PP1) before visbreaking is 30 to 140 g/10 min, such as 50 to 120 g/10 min.

In one embodiment of the present invention, the first propylene polymer (PP1) has been visbroken with a visbreaking ratio [final MFR2 (230°C/2.16 kg)/initial MFR2 (230°C/2.16 kg)] of at least 5. where the final MFR2 (230°C/2.16 kg) represents the MFR2 (230°C/2.16 kg) of the first propylene polymer (PP1) after visbreaking, and the initial MFR2 (230°C/2.16 kg) represents the MFR2 ( 230°C/2.16 kg) of the first propylene polymer (PP1) before visbreaking. Preferably, the first propylene polymer (PP1) has been visbroken with a visbreaking ratio [final MFR ₂ (230°C/2.16 kg) / initial MFR ₂ (230°C/2.16 kg)] from 5 to 25, where final MFR ₂ (230°C/2.16 kg) represents the MFR ₂ (230°C/2.16 kg) of the propylene homopolymer after visbreaking, and the initial MFR2 (230°C/2.16 kg) represents the MFR2 (230°C/2. 16 kg) of propylene homopolymer before visbreaking. More preferably, the first propylene polymer (PP1) has been visbroken with a visbreaking ratio [final MFR2 (230°C/2.16 kg)/initial MFR2 (230°C/2.16 kg)] of 5 to 15, where final MFR ₂ ( 230°C/2.16 kg) represents MFR ₂ (230°C/2.16 kg) of the first propylene polymer (PP1) after visbreaking, and initial MFR2 (230°C/2.16 kg) represents MFR2 (230°C /2.16 kg) of the first propylene polymer (PP1) before visbreaking.

As stated above, one of the characteristics of the first propylene polymer (PP1) is that the first propylene polymer (PP1) has undergone visbreaking. The preferred mixing devices for visbreaking are batch and continuous kniders, twin screw extruders and single screw extruders with special mixing sections and cokniders.

When the first propylene polymer (PP1) is visbroken by heat or under more controlled conditions using peroxide, the molar mass distribution (MWD) becomes narrower as long molecular chains are much more easily broken or cut, and the molar mass M is reduced and MFR2 is correspondingly increased. The increase in MFR2 increases with the amount of peroxide used.

Such visbreaking is typically carried out using a known method, such as using peroxide as a viscosity reducing agent. Typical viscosity-lowering agents are: 2,5-dimethyl-2,5-bis(tert-butyl-peroxy)hexane (DHBP) (for example, in solid form under the trade names Luperox 101 and Trigonox 101), 2,5-dimethyl -2,5-bis(tert.butylperoxy)hexine-3 (DYBP) (e.g. in solid form under the trade names Luperox 130 and Trigonox 145), dicumyl peroxide (DCUP) (Luperox DC and Perkadox BC peroxide), di -tert-butyl peroxide (DTBP) (for example, in solid form under the trade names Trigonox B and Luperox Di),

- 6 043459 tert-butyl cumyl peroxide (BCUP) (for example, in the form of a solid under the trade name Trigonox T and Luperox 801) and bis(tert-butylperoxy-isopropyl)benzene (DIPP) (for example, in the form of a solid under the trademark brand Perkadox 14S and Luperox DC). Suitable amounts of peroxide to be used in the process of the present invention are known in principle to one skilled in the art to which the present invention relates and can easily be calculated based on the amount of first visbreaked propylene polymer (PP1), MFR2 (230° C./ 2.16 kg) value for the first propylene polymer (PP1) subjected to visbreaking, and the specified target MFR ₂ (230°C/2.16 kg) of the resulting product. Accordingly, typical amounts of peroxide visbreaking agent range from 0.005 to 0.7% by weight, more preferably from 0.01 to 0.4% by weight, based on the total amount of first propylene polymer (PP1) used.

Typically, visbreaking in the present invention is carried out in an extruder under suitable conditions and an increased melt flow rate. During the visbreaking process, higher molar mass chains of the starting product are broken statistically significantly more often than lower molar mass molecules, resulting in an overall decrease in average molecular weight and an increase in melt flow rate.

The first propylene polymer (PP1) is preferably a first propylene polymer (PP1) obtained by visbreaking, preferably by visbreaking using peroxide.

An additional characteristic of the first propylene polymer (PP1) is the low number of erroneous propylene insertions in the polymer chain, which indicates that the first propylene polymer (PP1) is produced in the presence of a Ziegler-Natta catalyst, preferably in the presence of a Ziegler-Natta catalyst (ZN-Cl) , as described in more detail below. Accordingly, the first propylene polymer (PP1) is preferably characterized by a small amount of 2,1 erythro regiodefects, that is, equal to or less than 0.4 mol.%, more preferably equal to or less than 0.2 mol.%, such as no more than 0. 1 mol.%, as determined using 13C-NMR spectroscopy. In one substantially preferred embodiment of the present invention, 2,1erythro regiodefects are not detected.

Preferably, the first propylene polymer (PP1) has a fairly low XCS content, that is, an XCS content of less than 4.1% by weight. Accordingly, the first propylene polymer (PP1) is preferably has a xylene cold soluble fraction (XCS) content in the range from 1.0 to 4.0 wt.%, more preferably in the range from 2.0 to 3.8 wt.%, even more preferably in the range from 2. 2 to 3.5 wt.%.

The amount of xylene cold soluble fraction (XCS) further indicates that the first propylene polymer (PP1) is preferably free of any elastomeric polymer component such as ethylene propylene rubber. In other words, the first propylene polymer (PP1) should not be a heterophasic polypropylene, that is, a system consisting of a polypropylene matrix in which an elastomeric phase is dispersed. Such systems are characterized by a fairly high content of the fraction soluble in cold xylene.

The amount of xylene cold soluble fraction (XCS) further indicates that the first propylene polymer (PP1) preferably does not contain elastomeric (co)polymers forming inclusions as a second phase to improve mechanical properties. A polymer containing elastomeric (co)polymers, since second phase inserts will instead be referred to as heterophasic, and are preferably not part of the present invention. The presence of second phases or so-called inclusions can be seen using, for example, high-resolution microscopy such as electron microscopy or atomic force microscopy, or dynamic mechanical thermal analysis (DMTA). In particular, when using DMTA, the presence of a multiphase structure can be determined by the presence of at least two different glass transition temperatures.

Accordingly, preferably the first propylene polymer (PP1) of the present invention does not have a glass transition temperature below -30°C, preferably below -25°C, more preferably below -20°C.

On the other hand, in one preferred embodiment of the present invention, the first propylene polymer (PP1) of the present invention has a glass transition temperature in the range of -12 to 5°C, more preferably in the range of -10 to 4°C.

Additionally, the first propylene polymer (PP1) is preferably crystalline. As used herein, the term crystalline indicates that the first propylene polymer (PP1) has a sufficiently high melting point. Accordingly, the first propylene polymer (PP1) specified in the specification of this patent application is crystalline unless otherwise clearly stated. Therefore, the first propylene polymer (PP1) preferably has a melting temperature Tm, measured using differential scanning calorimetry (DSC), of at least 158°C, more preferably at least 160°C, even more preferably at least 161°C, such as in the range from 161°C to 165°C.

Additionally, preferably the first propylene polymer (PP1) has a crystallization temperature Tc, measured using differential scanning calorimetry (DSC), equal to or greater than 110°C, more preferably in the range of 110 to 128°C, more preferably in the range from 114 to 120°C.

Preferably, the first propylene polymer (PP1) is produced by polymerizing propylene in the presence of a Ziegler-Natta catalyst as follows. More preferably, the first propylene polymer (PP1) of the present invention is produced by a process described in more detail below using a Ziegler-Natta catalyst.

The first propylene polymer (PP1) of the present invention is preferably prepared in the presence of:

(a) a Ziegler-Natta (ZN-Cl) catalyst containing IUPAC Group 4-6 transition metal compounds (TC), a Group 2 metal compound (MC) and an internal donor (ID);

(b) optionally a cocatalyst (Co), and (c) optionally an external donor (ED).

Preferably, the first propylene polymer (PP1) is produced using a sequential polymerization method, as specified below, comprising at least one reactor, such as two reactors (R1) and (R2). Preferably, the first propylene polymer (PP1) is produced in one polymerization reactor (R1).

The method for producing propylene homopolymer along with the Ziegler-Natta catalyst will now be described in more detail.

The polymerization reactor (R1) may be a gas phase reactor (GPR) or a slurry reactor (SR). The gas phase reactor (GPR) of the present invention is preferably a fluidized bed reactor, a fast fluidized bed reactor, a fixed bed reactor, or any combination thereof.

Preferably, the polymerization reactor (R1) is a slurry reactor (SR) and may be any continuous or simple batch stirred tank reactor, or a loop reactor for carrying out bulk or slurry polymerization. Bulk means polymerization in a reaction medium containing at least 60% (w/w) monomer. In the present invention, the slurry reactor (SR) is preferably (for bulk polymerization) a loop reactor (LR).

The second polymerization reactor (R2) and any subsequent reactor, if present, is preferably a gas phase reactor (GPR). Such gas phase reactors (GPRs) can be any mechanically stirred reactors or fluidized bed reactors. Preferably, gas phase reactors (GPR) include a fluidized bed reactor with mechanical stirring with a gas flow rate of at least 0.2 m/second. Therefore, it is understood that the gas phase reactor is a fluidized bed reactor, preferably with a mechanical stirrer.

If present, in any subsequent reactor, the propylene homopolymer of the first polymerization reactor (R1) is preferably directly fed into the second polymerization reactor (R2), that is, into the (first) gas phase reactor (GPR1), without a flash step between stages. This type of direct feed is described in EP 887379 A, EP 887380 A, EP 887381 A and EP 991684 A. As used in the specification of this patent application, the term direct feed refers to a method where the contents of the first polymerization reactor (R1), that is, the first circulation reactor ( LR), fed directly to the next stage in the gas-phase reactor.

Alternatively, the propylene homopolymer from the first polymerization reactor (R1), more preferably the polymer slurry from the loop reactor (LR), can also be sent to a flash step or through an additional concentration step before being fed to the second polymerization reactor (R2), i.e. into a gas phase reactor (GPR). Accordingly, as used herein, the term indirect feed refers to a process in which the contents of a first polymerization reactor (R1), a loop reactor (LR), i.e., a polymer slurry, is supplied to a second polymerization reactor (R2), a (first) gas-phase reactor (GPR1), when using the reaction medium separating device, and the reaction medium is removed from the separating device as a gas.

However, preferably the propylene polymer (PP1) is produced in a single reactor, that is, a polymerization reactor (R1) representing a loop reactor (LR).

If required, a pre-polymerization reactor is placed upstream of the slurry reactor (SR), that is, the loop reactor (LR).

The Ziegler-Natta catalyst is fed into the first polymerization reactor (R1). In the case where the process also uses a pre-polymerization step, preferably all of the Ziegler-Natta catalyst is fed to the pre-polymerization reactor. The prepolymerization product containing the Ziegler-Natta catalyst is then transferred to the first polymerization reactor (R1).

A preferred multi-stage process is a gas-phase process such as that proposed by Borealis A/S, Denmark (known as the BORSTAR® technology), described for example in patent literature such as EP 0887379, WO 92/12182, WO 2004/000899, WO 2004/111095,

WO 99/24478, WO 99/24479 or WO 00/68315.

Particularly good results are achieved in the case of careful selection of temperatures in the reactors.

Accordingly, preferably the operating temperature in the first polymerization reactor (R1) is in the range of 62 to 90°C, more preferably in the range of 65 to 85°C, even more preferably in the range of 67 to 83°C.

Typically, the pressure in the polymerization reactor (R1), preferably in the loop reactor (LR), is in the range of 20 to 80 bar, preferably 30 to 70 bar, such as 35 to 65 bar.

Preferably, hydrogen is supplied to each polymerization reactor to control the molecular weight, that is, the flow rate of the MFR2 melt.

Preferably, the average residence time in the polymerization reactors (R1) and (R2) is relatively long. Typically, the average residence time (τ) is defined as the ratio of the volume of the reaction mixture (VR) to the space velocity of the reactor exit (Qo) (i.e. VR/Q _o ), that is, T=VR/Q _o [t=V _r /Q ₀ ]. In the case of a circulation reactor, the volume of the reaction mixture (VR) is equal to the volume of the reactor.

Accordingly, the average residence time (τ) in the polymerization reactor (R1) is preferably at least 15 minutes, more preferably in the range of 15 to 90 minutes, even more preferably in the range of 20 to 80 minutes, such as in the range of 24 to 60 min.

As stated above, the process of the present invention may include, in addition to the (main) polymerization of the propylene homopolymer in a polymerization reactor (R1), a preceding prepolymerization in a prepolymerization reactor (PR) upstream of the polymerization reactor (R1).

The pre-polymerization reactor (PR) produces polypropylene (Pre-PP). Pre-polymerization is carried out in the presence of a Ziegler-Natta catalyst. According to this embodiment of the present invention, the Ziegler-Natta catalyst, cocatalyst (Co) and external donor (ED) are all introduced in the pre-polymerization step. However, this does not exclude the possibility that at a later stage in the polymerization process, for example, an additional cocatalyst (Co) and/or an external donor (ED) is added, for example, to the first reactor (R1). In one embodiment of the present invention, the Ziegler-Natta catalyst, cocatalyst (Co), and external donor (ED) are added only to the prepolymerization reactor (PR) if prepolymerization is performed.

Typically, the pre-polymerization reaction is carried out at a temperature of 0 to 60°C, preferably 15 to 50°C, and more preferably 20 to 45°C.

The pressure in the pre-polymerization reactor is not critical, but must be high enough to maintain the reaction mixture in the liquid phase. Therefore, the pressure can be from 20 to 100 bar, for example from 30 to 70 bar.

In one preferred embodiment of the present invention, the prepolymerization is carried out as a bulk suspension polymerization in liquid propylene, that is, the liquid phase primarily contains propylene with optional inert components dissolved therein. Additionally, according to the present invention, ethylene is supplied during pre-polymerization as described above.

It is also possible to add other components at the pre-polymerization stage. Accordingly, hydrogen may also be introduced in the pre-polymerization step to control the molecular weight of the polypropylene (Pre-PP), as is known to one skilled in the art. Additionally, antistatic additives can be added to prevent particle adhesion to each other and to the reactor walls.

Precise control of pre-polymerization conditions and reaction parameters is within the competence of one skilled in the art to which the present invention relates.

In view of the above conditions of the pre-polymerization process, a mixture (Ml) of Ziegler-Natta catalyst and polypropylene (Pre-PP) is preferably produced in a pre-polymerization reactor (PR). Preferably, the Ziegler-Natta catalyst is (finely) dispersed in polypropylene (Pre-PP). In other words, the Ziegler-Natta catalyst particles introduced into the prepolymerization reactor (PR) are broken down into smaller fragments, which are evenly distributed in the growing polypropylene (Pre-PP). The sizes of the introduced Ziegler-Natta catalyst particles along with the resulting fragments are not essential for the present invention and are within the competence of one skilled in the field of technology to which the present invention relates.

As stated above, if pre-polymerization is carried out, then after said pre-polymerization, the mixture (MI) of Ziegler-Natta catalyst and polypropylene (Pre-PP) obtained in the pre-polymerization reactor (PR) is fed into the first reactor (R1). Typically, the total amount of polypropylene (Pre-PP) in the final polypropylene (PP) is quite low, and is typically no more than 5.0 wt.%, more preferably no more than 5.0 wt.%, more preferably not more than 4.0 wt.%, even more preferably in the range from 0.5 to 4.0 wt.%, such

- 9 043459 as in the range from 1.0 to 3.0 wt.%.

In the case where no pre-polymerization is carried out, propylene and other ingredients such as the Ziegler-Natta catalyst are directly fed into the first polymerization reactor (R1).

Accordingly, the propylene homopolymer is preferably produced by a process comprising the following steps under the above conditions:

(a) in a first polymerization reactor (R1), that is, a loop reactor (LR), propylene is polymerized to produce a first propylene polymer (PP1).

The above pre-polymerization step is carried out before step (a).

In the above method, a Ziegler-Natta catalyst (ZN-Cl) is used to produce the first propylene polymer (PP1). This Ziegler-Natta (ZN-d) catalyst may be any stereospecific Ziegler-Natta (ZN-Cl) catalyst for the polymerization of propylene, which is preferably capable of catalyzing the polymerization and copolymerization of propylene and comonomers under a pressure of 500 to 10,000 kPa, essentially 2,500 to 8000 kPa and at a temperature of from 40 to 110°C, essentially from 60 to 110°C.

Preferably, the Ziegler-Natta catalyst (ZN-Cl) includes a Ziegler-Natta type catalyst including an internal donor component that can be used in high temperature polymerization of 80° C. or more. Such a high yield Ziegler-Natta (ZN-Cl) catalyst may contain succinate, diester, phthalate and the like or mixtures thereof as internal donor (ID) and are, for example, commercially available from LyondellBasell under the trade name Avant ZN. Examples of the Avant ZN series are Avant ZN 126 and Avant ZN 168. Avant ZN 126 is a Ziegler-Natta catalyst with 3.5 wt.% titanium and a diester compound as an internal electron donor, commercially available from LyondellBasell. Avant ZN 168 is a Ziegler-Natta catalyst with 2.6 wt.% titanium and a succinate compound as an internal electron donor, commercially available from LyondellBasey. An additional example of the Avant ZN series is the ZN180M catalyst from LyondellBasell.

Further suitable catalysts are described, for example, in WO 2012/007430, EP 2610271, EP 261027 and EP 2610272.

Preferably, the Ziegler-Natta (ZN-Cl) catalyst is used in combination with an aluminum alkyl compound cocatalyst and optionally external donors.

An external donor (ED) is preferably present as an additional component in the polymerization process of the present invention. Suitable external donors (ED) include certain silanes, ethers, esters, amines, ketones, heterocyclic compounds, and mixtures thereof. As such, the use of silanes is preferred. It is most preferable to use silanes with the general formula

R ^a pR ^b _q Si(OR ^c )(4.pq) where R ^a , R ^b and R ^c denotes a hydrocarbon radical, in particular an alkyl or cycloalkyl group, and where p and q are numbers ranging from 0 to 3, and the sum of p + q is equal to or less than 3. R ^a , R ^b and R ^c may be selected independently of each other and may be identical or different. Specific examples of such silanes are (tert-butyl)^( _OSH3 ) ₂ , (cyclohexyl)(methyl)Si( _OSH3 ) ₂ , (phenyl) _2Si ( _OSH3 ) ₂ , and (cyclopentyl) _2Si ( _OSH3 ) ₂ . or with the general formula

Si(OCH ₂ CH3)3(NR ³ R ⁴ ), where R ³ and R ⁴ can represent identical or different hydrocarbon groups with from 1 to 12 carbon atoms.

R ³ and R ⁴ may be independently selected from the group consisting of linear aliphatic hydrocarbon compounds of 1 to 12 atoms, branched aliphatic or aromatic hydrocarbon compounds of 1 to 12 atoms, and cyclic aliphatic hydrocarbon compounds of 1 to 12 atoms. As such, it is preferred that R ³ and R ⁴ be independently selected from the group consisting of methyl, ethyl, n-propyl, n-butyl, octyl, decanyl, isopropyl, isobutyl, isopentyl, t-butyl, tretamyl, neopentyl, cyclopentyl, cyclohexyl, methylcyclopentyl and cycloheptyl.

More preferably, both R ¹ and R ² are identical, even more preferably, both R ³ and R ⁴ are an ethyl group.

As such, preferred external donors (ED) are a dicyclopentyldimethoxysilane donor (D-donor) or a cyclohexylmethyldimethoxysilane donor (C-donor).

In addition to the Ziegler-Natta catalyst (ZN-C) and optional external donor (ED), a cocatalyst can be used. Preferably, the cocatalyst is an IUPAC group 13 compound, for example an organoaluminum compound such as an aluminum compound, such as an aluminum alkyl compound, an aluminum halide compound or an aluminum alkyl halide compound. Accordingly, in one specific embodiment of the present invention, the cocatalyst (Co) is a trialkylaluminum such as triethylaluminum (TEAL), dialkylaluminum chloride or alkylaluminum chloride, or mixtures thereof. In one specific embodiment of the present invention, the cocatalyst (Co) is triethylaluminum (TEAL).

- 10 043459

Preferably, the ratio between cocatalyst (Co) and external donor (ED) [Co/ED] and/or the ratio between cocatalyst (Co) and transition metal (TM) is carefully selected.

[Co/TM].

Accordingly, (a) the molar ratio of cocatalyst (Co) to external donor (ED) [Co/ED] should be in the range of 5 to 45, preferably in the range of 5 to 35, more preferably in the range of 5 to 25, even more preferably ranging from 4.5 to 25;

and optionally (b) the molar ratio of cocatalyst (Co) to titanium compound (TC) [Co/TC] should be in the range of above 80 to 500, preferably in the range of 90 to 350, even more preferably in the range of 100 to 300.

Second propylene polymer (PP2).

The second propylene polymer (PP2) preferably has a moderate melt flow rate. Accordingly, preferably the melt flow rate MFR ₂ (230° C., 2.16 kg), as determined according to ISO 1133, of the second propylene polymer (PP2) is in the range of 30 to 250 g/10 min, more preferably in the range of 40. 0 to 120.0 g/10 min, even more preferably in the range from 60.0 to 90.0 g/10 min.

Preferably, the second propylene polymer (PP2) has a fairly low XCS content, that is, an XCS content of less than 4.1% by weight. Accordingly, the second propylene polymer (PP2) preferably has xylene cold soluble fraction (XCS) content in the range from 1.0 to 4.0 wt.%, more preferably in the range from 2.0 to 3.8 wt.%, even more preferably in the range from 2.2 to 3.5 wt.%.

Therefore, similar to the first propylene polymer (PP1), preferably the second propylene polymer (PP2) is free of any elastomeric component. In this regard, reference is made to the above definitions.

Accordingly, preferably the second propylene polymer (PP2) of the present invention does not have a glass transition temperature below -30°C, preferably below -25°C, more preferably below -20°C.

On the other hand, in one preferred embodiment of the present invention, the second propylene polymer (PP2) of the present invention has a glass transition temperature in the range of -12 to 5°C, more preferably in the range of -10 to 4°C.

Additionally, preferably the second propylene polymer (PP2) is a crystalline propylene homopolymer. With respect to the term crystalline as used herein, reference is made to the above definition. Therefore, the second propylene polymer (PP2) preferably has a melting point Tm, measured using differential scanning calorimetry (DSC), of at least 158°C, more preferably at least 160°C, even more preferably at least 161°C , such as in the range from 161°C to 165°C.

Additionally, preferably the second propylene polymer (PP2) has a crystallization temperature Tg, measured using differential scanning calorimetry (DSC), equal to or greater than 108°C, more preferably in the range of 110 to 128°C, more preferably in the range of 112 to 120 °C.

Preferably, the second propylene polymer (PP2) is produced by polymerizing propylene in the presence of a Ziegler-Natta catalyst. More preferably, the second propylene polymer (PP2) of the present invention is produced by a process using a Ziegler-Natta catalyst.

To prepare the second propylene polymer (PP2), the polymerization method and Ziegler-Natta catalyst described above for the first propylene polymer (PP1) can be used. Therefore, reference is made to the Ziegler-Natta process and catalyst described above for the first propylene polymer (PP1).

Third propylene polymer (PP3).

The third propylene polymer (PP3) preferably has a melt flow rate MFR ₂ (230° C., 2.16 kg), as determined according to ISO 1133, ranging from 0.1 to 50.0 g/10 min, more preferably ranging from 1.0 to 30.0 g/10 min, even more preferably in the range of 10.0 to 28.0 g/10 min.

Also preferably, the third propylene polymer (PP3) is characterized by a fairly low XCS content, that is, an XCS content of less than 4.1% by weight. Accordingly, the third propylene polymer (PP3) preferably has a cold xylene soluble fraction (XCS) content in the range of 1.0 to 4.0 wt.%, more preferably in the range of 2.0 to 3.8 wt.%, even more preferably in the range of 2 .0 to 3.5 wt.%.

Therefore, similar to the first propylene polymer (PP1) and the second propylene polymer (PP2), preferably the third propylene polymer (PP3) is free of any elastomeric component. In this regard, reference is made to the above definitions.

Accordingly, preferably the third propylene polymer (PP3) of the present invention does not have a glass transition temperature below -30°C, preferably below -25°C, more preferably below -20°C.

On the other hand, in one preferred embodiment of the present invention, the third propylene polymer (PP3) of the present invention has a glass transition temperature in the range of -12 to 5°C, more preferably in the range of -10 to 4°C.

Additionally, preferably the third propylene polymer (PP3) is a crystalline propylene homopolymer. With respect to the term crystalline as used herein, reference is made to the above definition. Therefore, the third propylene polymer (PP3) preferably has a melting point Tm, measured using differential scanning calorimetry (DSC), of at least 160°C, even more preferably at least 161°C, even more preferably at least 163° C, such as in the range from 163°C to 167°C.

Additionally, preferably the third propylene polymer (PP2) has a crystallization temperature Tg, measured using differential scanning calorimetry (DSC), equal to or greater than 110°C, more preferably in the range of 110 to 130°C, more preferably in the range of 114 to 128 °C.

Preferably, the third propylene polymer (PP3) has been nucleated, more preferably α-nucleated. Accordingly, preferably the third propylene polymer (PP3) is prepared in the presence of a nucleating agent, preferably an α-nucleating agent.

In the case where the third propylene polymer (PP3) contains an α-nucleating agent, it is preferably free from β-nucleating agents, the α-nucleating agent is preferably selected from the group consisting of (i) a salt of monocarboxylic acids and polycarboxylic acids, for example benzoate sodium or aluminum tert-butyl benzoate and (ii) dibenzylidene sorbitol (for example, 1,3:2,4 dibenzylidene sorbitol) and C ₁ -C ₈ -alkyl-substituted dibenzylidene sorbitol derivatives, such as methyldibenzylidene sorbitol, ethyl dibenzylidene sorbitol or dimethyldibenzylidene sorbitol (for example, 1,3:2, 4 di(methylbenzylidene) sorbitol), or nonitol-substituted derivatives such as 1,2,3,-trideoxy-4,6:5,7-bis-O-[(4-propylphenyl)methylene]-nonitol, and ( iii) salts of phosphoric acid diesters, for example sodium 2,2'-methylenebis(4,6,-di-tertbutylphenyl) phosphate or aluminum hydroxy-bis[2,2'-methylenebis(4,6-di-t -butylphenyl) phosphate] and (iv) vinylcycloalkane polymer and vinylalkane polymer (as described in more detail below) and (v) mixtures thereof.

Such additives are generally commercially available and are described, for example, in Plastic Additives Handbook, 5th edition, 2001 of Hans Zweifel.

Preferably, the third propylene polymer (PP3) contains up to 5 wt.% αnucleating agent. In a preferred embodiment, the propylene homopolymer contains no more than 500 ppm, more preferably 0.025 to 200 ppm, more preferably 0.1 to 200 ppm, even more preferably 0.3 to 200 ppm, most preferably 0.3 to 100 ppm α-nucleating agent, in particular selected from the group consisting of dibenzylidene sorbitol (for example, 1,3:2,4 dibenzylidene sorbitol), a dibenzylidene sorbitol derivative, preferably dimethyldibenzylidene sorbitol (for example, 1,3:2,4 di(methylbenzylidene) sorbitol), or nonite-substituted derivatives such as 1,2,3,-trideoxy-4,6:5,7-bis-O-[(4-propylphenyl)methylene]-nonite, vinylcycloalkane polymer, vinylalkane polymer and mixtures thereof.

The third propylene polymer (PP2b) of the present invention is preferably prepared in the presence of:

(a) a Ziegler-Natta catalyst (ZN-C2) containing an IUPAC Group 4-6 transition metal compound (TC), a Group 2 metal compound (MC) and an internal donor (ID);

(b) optionally a cocatalyst (Co), and (c) optionally an external donor (ED).

Preferably, the third propylene polymer (PP3) is produced using a sequential polymerization process as set forth below, comprising at least two reactors (R1) and (R2), in the first reactor (R1) a propylene homopolymer fraction (PP3a) is obtained and then transferred to second reactor (R2), in the second reactor (R2) a second fraction of propylene homopolymer (PP3b) is obtained in the presence of a first fraction of propylene homopolymer (PP3a).

Next, a method for producing propylene homopolymer along with a Ziegler-Natta catalyst (ZN-C2) will be described in more detail.

As stated above, the third propylene polymer (PP3) is preferably produced using a sequential polymerization method.

- 12 043459

As used herein, the term sequential polymerization system indicates that the third propylene polymer (PP3) is produced in at least two reactors connected in series. Accordingly, the polymerization system of the present invention includes at least a first reactor (1R), a second reactor (2R), and optionally a third reactor (3R). As used herein, the term polymerization reactor refers to the location where the main polymerization occurs. Therefore, in the case where the process consists of two polymerization reactors, this definition does not exclude the possibility that the overall system includes, for example, a pre-polymerization step in a pre-polymerization reactor. As used in the specification of this patent application, the term consists of refers only to the closed formulation in terms of the main polymerization reactors.

Preferably, at least one of the two polymerization reactors (R1) and (R2) is a gas phase reactor (GPR). Even more preferably, the second polymerization reactor (R2) and optionally the third polymerization reactor (R3) are gas phase reactors (GPR), that is, the first gas phase reactor (GPR1) and the second gas phase reactor (GPR2). The gas phase reactor (GPR) of the present invention is preferably a fluidized bed reactor, a fast fluidized bed reactor, a fixed bed reactor, or any combination thereof.

Accordingly, the first polymerization reactor (R1) is preferably a slurry reactor (SR) and may be any continuous reactor or a simple batch reactor or a loop reactor for carrying out bulk or slurry polymerization. Bulk means polymerization in a reaction medium containing at least 60% (w/w) monomer. In the present invention, the slurry reactor (SR) is preferably (for bulk polymerization) a loop reactor (LR). Accordingly, the average concentration of the first fraction (1st F) of the third propylene polymer (PP3), that is, the first fraction of the propylene homopolymer (PP3a), in the polymer suspension in the loop reactor (LR) is generally from 15 wt.% to 55 wt. % of the total mass of the polymer suspension in the loop reactor (LR). In one preferred embodiment of the present invention, the average concentration of the first propylene homopolymer fraction (PP3a) in the polymer slurry in the loop reactor (LR) is from 20 wt% to 55 wt%, and more preferably from 25 wt% to 52 wt% of the total mass of the polymer suspension in the loop reactor (LR).

Preferably, the propylene homopolymer of the first polymerization reactor (R1), that is, the first propylene homopolymer fraction (PP3a), more preferably the polymer suspension in the loop reactor (LR) containing the first propylene homopolymer fraction (PP3a), is directly fed into the second polymerization reactor (R2), that is, into the (first) gas phase reactor (GPR1) without a flash step between stages. This type of direct feed is described in EP 887379 A, EP 887380 A, EP 887381 A and EP 991684 A. As used in the specification of this patent application, the term direct feed refers to a method where the contents of the first polymerization reactor (R1), that is, the first circulation reactor ( LR), a polymer suspension containing the first fraction of propylene homopolymer (PP3a), is fed directly to the next stage into a gas-phase reactor.

Alternatively, the propylene homopolymer from the first polymerization reactor (R1), i.e. the first propylene homopolymer fraction (PP3a), can also be sent to a flash step or through an additional concentration step before being fed into the second polymerization reactor (R2), i.e. gas phase reactor (GPR). Accordingly, as used herein, the term indirect feed refers to a process in which the contents of a first polymerization reactor (R1), a loop reactor (LR), i.e., a polymer slurry, is supplied to a second polymerization reactor (R2), a (first) gas-phase reactor (GPR1), when using the reaction medium separating device, and the reaction medium is removed from the separating device as a gas.

More preferably, the second polymerization reactor (R2) and any subsequent reactor, for example, the third polymerization reactor (R3), are preferably gas phase reactors (GPR). Preferably, gas phase reactors (GPRs) can be any mechanically stirred reactors or fluidized bed reactors. Preferably, gas phase reactors (GPR) include a fluidized bed reactor with mechanical stirring with a gas flow rate of at least 0.2 m/second. Therefore, it is understood that the gas phase reactor is a fluidized bed reactor, preferably with a mechanical stirrer.

Therefore, in a preferred embodiment, the first polymerization reactor (R1) is a slurry reactor (SR), such as a loop reactor (LR), wherein the second polymerization reactor (R2) and any optional downstream reactor, such as the third polymerization reactor (R3), represent gas phase reactors (GPR). Accordingly, the process of the present invention uses at least two (R1) and (R2) or three polymerization reactors (R1), (R2) and (R3), namely a slurry reactor (SR), such as a loop reactor (LR ), the first gas-phase reactor (GPR1) and the second gas-phase reactor (GPR2), combined in a series. If required, a pre-polymerization reactor is placed upstream of the slurry reactor (SR).

- 13 043459

The Ziegler-Natta catalyst (ZN-C2) is fed into the first polymerization reactor (R1) and then transferred with the polymer (slurry) produced in the first polymerization reactor (R1) to subsequent reactors. In the case where the process also uses a pre-polymerization step, preferably all of the Ziegler-Natta catalyst (ZN-C2) is fed to the pre-polymerization reactor. The prepolymerization product containing the Ziegler-Natta catalyst (ZN-C2) is then transferred to the first polymerization reactor (R1).

A preferred multi-stage process is a gas-phase process such as that proposed by Borealis A/S, Denmark (known as the BORSTAR® technology), described for example in patent literature such as EP 0887379, WO 92/12182, WO 2004/000899, WO 2004/111095, WO 99/24478, WO 99/24479 or WO 00/68315.

An additional, suitable suspension-gas phase method is the Spheripol® Basell process.

Particularly good results are achieved in the case of careful selection of temperatures in the reactors.

Accordingly, preferably the operating temperature in the first polymerization reactor (R1) is in the range of 62 to 90°C, more preferably in the range of 65 to 85°C, even more preferably in the range of 67 to 82°C.

Alternatively or in addition to the preceding paragraph, preferably the operating temperature in the second polymerization reactor (R2) and optionally in the third reactor (R3) is in the range of 62 to 95°C, more preferably in the range of 67 to 92°C.

Preferably, the operating temperature in the second polymerization reactor (R2) is equal to or higher than the operating temperature in the first polymerization reactor (R1). Accordingly, the preferred operating temperature is:

(a) in the first polymerization reactor (R1) is in the range from 62 to 90°C, more preferably in the range from 65 to 85°C, even more preferably in the range from 67 to 82°C; and (b) in the second polymerization reactor (R2) is in the range from 75 to 95°C, more preferably in the range from 78 to 92°C, even more preferably in the range from 78 to 88°C, provided that the operating temperature in the second polymerization reactor (R2) is equal to or higher than the operating temperature in the first polymerization reactor (R1).

Typically, the pressure in the first polymerization reactor (R1), preferably the loop reactor (LR), is in the range of 20 to 80 bar, preferably 30 to 70 bar, such as 35 to 65 bar, while the pressure in the second reactor polymerization (R2), that is, in the (first) gas phase reactor (GPR-1), and optionally in any subsequent reactor, such as in the third polymerization reactor (R3), for example, in the second gas phase reactor (GPR-2), is in ranging from 5 to 50 bar, preferably from 15 to 40 bar.

Preferably, hydrogen is supplied to each polymerization reactor to control the molecular weight, that is, the flow rate of the MFR ₂ melt.

Preferably, the average residence time in the polymerization reactors (R1) and (R2) is relatively long. Typically, the average residence time (τ) is defined as the ratio of the volume of the reaction mixture (VR) to the space velocity of the reactor exit (Q _o ) (that is, V _R /Q _o ), that is, T = VR / Q _o [t = V _r /Q ₀ ]. In the case of a circulation reactor, the volume of the reaction mixture (VR) is equal to the volume of the reactor.

Accordingly, the average residence time (τ) in the first polymerization reactor (R1) is preferably at least 15 minutes, more preferably in the range from 15 to 90 minutes, even more preferably in the range from 20 to 80 minutes, such as in the range from 24 to 60 minutes, and/or the average residence time (τ) in the second polymerization reactor (R2) is preferably at least 70 minutes, more preferably in the range from 70 to 220 minutes, even more preferably in the range from 80 to 210 minutes, even more preferably in the range of 90 to 200 minutes, such as in the range of 90 to 190 minutes. Preferably, the average residence time (τ) in the third polymerization reactor (R3), if present, is preferably at least 30 minutes, more preferably in the range of 30 to 120 minutes, even more preferably in the range of 40 to 100 minutes, such as ranging from 50 to 90 minutes.

As stated above, the process of the present invention may include, in addition to the (main) polymerization of the propylene homopolymer in at least two polymerization reactors (R1, R3 and optionally R3), preceded by a pre-polymerization in a pre-polymerization reactor (PR) upstream of the first reactor polymerization (R1).

The pre-polymerization reactor (PR) produces polypropylene (Pre-PP). Pre-polymerization is carried out in the presence of a Ziegler-Natta catalyst (ZN-C2). According to this embodiment of the present invention, the Ziegler-Natta catalyst (ZN-C2), cocatalyst (Co) and external donor (ED) are all introduced in the pre-polymerization step. However, this does not exclude the possibility that at a later stage in the polymerization process, for example, an additional cocatalyst (Co) and/or an external donor (ED) is added, for example, to the first reactor (R1). In one embodiment of the present invention, the Ziegler-Natta catalyst (ZN-C2), cocatalyst (Co), and

- 14 043459 external donor (ED) is added only to the pre-polymerization reactor (PR) if pre-polymerization is carried out.

Typically, the pre-polymerization reaction is carried out at a temperature of 0 to 60°C, preferably 15 to 50°C, and more preferably 20 to 45°C.

The pressure in the pre-polymerization reactor is not critical, but must be high enough to maintain the reaction mixture in the liquid phase. Therefore, the pressure can be from 20 to 100 bar, for example from 30 to 70 bar.

In one preferred embodiment of the present invention, the prepolymerization is carried out as a bulk suspension polymerization in liquid propylene, that is, the liquid phase primarily contains propylene with optional inert components dissolved therein. Additionally, according to the present invention, ethylene is supplied during pre-polymerization as described above.

It is also possible to add other components at the pre-polymerization stage. Accordingly, hydrogen may also be introduced in the pre-polymerization step to control the molecular weight of the polypropylene (Pre-PP), as is known to one skilled in the art. Additionally, antistatic additives can be added to prevent particle adhesion to each other and to the reactor walls.

Precise control of pre-polymerization conditions and reaction parameters is within the competence of one skilled in the art to which the present invention relates.

In view of the above conditions of the prepolymerization process, a mixture (MI) of Ziegler-Natta catalyst (ZNC2) and polypropylene (Pre-PP) is preferably produced in a prepolymerization reactor (PR). Preferably, the Ziegler-Natta catalyst (ZN-C2) is (finely) dispersed in polypropylene (Pre-PP). In other words, the Ziegler-Natta catalyst (ZN-C2) particles introduced into the prepolymerization reactor (PR) are broken down into smaller fragments, which are evenly distributed in the growing polypropylene (Pre-PP). The sizes of the introduced Ziegler-Natta catalyst (ZN-C2) particles, along with the resulting fragments, are not essential for the present invention and are within the purview of one skilled in the art to which the present invention relates.

As stated above, if pre-polymerization is carried out, then after said pre-polymerization, the mixture (MI) of Ziegler-Natta catalyst (ZN-C2) and polypropylene (PrePP) obtained in the pre-polymerization reactor (PR) is fed into the first reactor ( R1). Typically, the total amount of polypropylene (Pre-PP) in the final polypropylene (PP) is quite low, and is typically no more than 5.0 wt.%, more preferably no more than 5.0 wt.%, more preferably not more than 4.0% by weight, even more preferably in the range of 0.5 to 4.0% by weight, such as in the range of 1.0 to 3.0% by weight.

In the case where no pre-polymerization is carried out, propylene and other ingredients such as Ziegler-Natta catalyst (ZN-C2) are directly fed into the first polymerization reactor (R1).

Accordingly, the propylene homopolymer is preferably produced by a process comprising the following steps under the above conditions:

(a) in a first polymerization reactor (R1), i.e. a loop reactor (LR), polymerizes propylene to produce a first propylene homopolymer fraction (PP3a) of a third propylene polymer (PP3), (b) transferring said first propylene homopolymer fraction (A) into a second polymerization reactor (R2), (c) in a second polymerization reactor (R2), propylene is polymerized in the presence of a first propylene homopolymer fraction (PP3a) to produce a second propylene homopolymer fraction (PP3b), a third propylene polymer fraction (PP3), said first propylene homopolymer fraction (PP3a) and said second propylene homopolymer fraction (PP3b) form a third propylene polymer (PP3).

The above pre-polymerization step is carried out before step (a).

The catalyst used in the present invention is a solid Ziegler-Natta catalyst (ZN-C2) that contains an IUPAC Group 4-6 transition metal compound (TC) such as titanium, a Group 2 metal compound (MC) such as magnesium, and an internal the donor (ID) is not a phthalic acid ester, most preferably not a phthalic dicarboxylic acid diester, as described in more detail below. Therefore, the catalyst used in the present invention is completely free of unwanted phthalic compounds. Additionally, the solid catalyst is free of any external support material such as silicon or MgCl ₂ because the catalyst is self-supporting.

Additionally, the Ziegler-Natta catalyst (ZN-C2) can be determined by the production method. Accordingly, the Ziegler-Natta catalyst (ZN-C2) is preferably prepared by a process comprising the following steps:

a) a1) providing a solution of at least a group 2 metal alkoxy compound (Ax) representing the reaction product of a group 2 metal compound (MC) and an alcohol (A) containing, in addition to the hydroxyl group, at least one ester group optionally in an organic liquid reaction medium; or a2) a solution of at least an alkoxy compound of a group 2 metal (Ax'), representing the reaction product of a compound of a group 2 metal (MC) and an alcohol mixture of alcohol (A) and monohydric alcohol (B) with the formula ROH, optionally in an organic liquid reaction environment; or a3) providing a solution of a mixture of a Group 2 metal alkoxy compound (Ax) and a Group 2 metal alkoxy compound (Bx), representing the reaction product of a Group 2 metal compound (MC) and a monohydric alcohol (B), optionally in an organic liquid reaction medium; or a4) providing a solution of a Group 2 metal alkoxy compound with the formula M(OR ¹ )n(OR ² )mX2. _n .m or mixtures of group 2 alkoxides M(OR1) _n X ₂ . _n ' and M(OR ² )mX2_m', where M is a metal of group 2, X is a halogen, R ¹ and R ² are different alkyl groups with C2-C ₁₆ carbon atoms, and 0<n<2, 0<w< 2 and n+m+(2-nm)=2, provided that both n and mhO 0<n'<2 and 0<w'<2; And

b) adding to said solution from step a) at least one transition metal compound (TC) of groups 4-6 and

c) providing the solid particulate catalyst component, and adding an internal electron donor (ID), preferably a non-phthalic internal donor (ID), at any stage prior to step c).

The internal donor (ID) or its precursor is preferably added to the solution of step a) or to the transition metal compound before adding to the solution of step a).

According to the procedure mentioned above, the Ziegler-Natta catalyst (ZN-C) can be obtained using a precipitation method or an emulsion solidification method depending on the physical conditions, in particular the temperature used in steps b) and c). Also in the specification of this patent application, the emulsion is referred to as a two-phase liquid/liquid system.

Both methods (precipitation or emulsion solidification) produce a chemically identical catalyst.

In the precipitation method, a solution of step a) is combined with at least one transition metal compound (TM) of step b) and the entire reaction mixture is maintained at a temperature of at least 50°C, more preferably at a temperature in the range from 55 to 110°C, more preferably in the range from 70 to 100°C to ensure complete precipitation of the catalyst component in the form of solid particles (step c).

In the method for curing the emulsion in step b), at least one transition metal compound (TM) is typically added to the solution in step a) at a lower temperature, such as from 10 to below 50° C., preferably from -5 to 30° WITH. While mixing the emulsion, the temperature is typically maintained at -10 to below 40°C, preferably -5 to 30°C. Droplets of the dispersed phase of the emulsion form an active catalytic composition. The curing step (step c) of the droplets is suitably carried out by heating the emulsion to a temperature of 70 to 150°C, preferably 80 to 110°C.

In the present invention, it is preferable to use a catalyst obtained by an emulsion curing method.

In a preferred embodiment of the present invention, step a) uses a solution a2) or a3), that is, a solution (Ax') or a solution of a mixture of (Ax) and (Bx), in particular a solution a2).

Preferably the Group 2 metal (MC) is magnesium.

The above alkoxy magnesium compounds may be prepared in situ in the first step of the catalyst preparation process, step a), by reacting the magnesium compound with the above alcohol(s), or the above alkoxy magnesium compounds may be separately prepared alkoxy magnesium compounds, or they may even be commercially available as prepared magnesium alkoxy compounds and used in the process of preparing the catalyst of the present invention.

Illustrative examples of such preferred alcohols (A) are monoesters of dihydric alcohols (glycol monoesters). Preferred alcohols (A) are C ₂ -C ₄ glycol monoesters, where the ester groups contain from 2 to 18 carbon atoms, preferably from 4 to 12 carbon atoms. Preferred examples are 2-(2-ethylhexyloxy) ethanol, 2-butyloxy ethanol, 2hexyloxy ethanol and 1,3-propylene glycol monobutyl ether, 3-butoxy-2-propanol, with 2-(2-ethylhexyloxy)ethanol and 1, 3-propylene glycol monobutyl ether, 3-butoxy-2-propanol is essentially preferred.

Illustrative monohydric alcohols (B) are those with the formula ROH, where R represents a straight or branched C ₂ -C ₁₆ alkyl residue, preferably a C ₄ -C ₁₀ , more preferably a C ₆ -C ₈ alkyl residue. The most preferred monohydric alcohol is 2-ethyl-1-hexanol or octanol.

Preferably, a mixture of alkoxy compounds Mg (Ax) and (Bx) or a mixture of alcohols (A) and (B), respectively, is used, and is used in a molar ratio of Bx:Ax or B:A from 10:1 to 1:10, more preferably from 6:1 to 1:6, most preferably 4:1 to 1:4.

- 16 043459

The magnesium alkoxy compound may be a reaction product of the above alcohol(s), and the magnesium compound is selected from magnesium dialkyl compounds, magnesium alkyl compound alkoxides, magnesium dialkoxides and magnesium alkoxy halides and magnesium alkyl halides. The alkyl groups may be identical or different from C1-C2o alkyl, preferably C2-C10 alkyl groups. Typical alkoxides of alkyl magnesium compounds used are ethyl magnesium butoxide, butyl magnesium pentoxide, octyl magnesium butoxide and octyl magnesium octoxide. Preferably, a magnesium dialkyl is used. Most preferably, the magnesium dialkyl is magnesium butyl-octyl or magnesium butyl-ethyl.

It is also possible for the magnesium compound to react, in addition to the alcohol (A) and the alcohol (B), also with a polyhydric alcohol (C) of the formula R(OH)m to produce said magnesium alkoxide compounds. Preferred polyhydric alcohols, when used, are alcohols wherein R is a straight-chain, cyclic or branched C2-C ₁₀ hydrocarbon moiety and m is an integer from 2 to 6.

Therefore, the magnesium alkoxy compounds of step a) are selected from the group consisting of magnesium dialkyloxide compounds, magnesium diaryloxy compounds, magnesium alkyloxy halides, magnesium aryloxy halides, magnesium alkoxides, magnesium aryl alkoxides and magnesium alkoxy aryloxides.

The solvents used to prepare the catalyst of the present invention may be selected from aromatic and aliphatic straight-chain, branched and cyclic hydrocarbons of 5 to 20 carbon atoms, preferably 5 to 12 carbon atoms, or mixtures thereof. Suitable solvents include benzene, toluene, cumene, xylene, pentane, hexane, octane and nonane. As such, hexanes and pentanes are preferred.

The reaction to obtain a magnesium compound complex (MC) can be carried out at temperatures from 40° to 70°C. The most suitable temperature is selected depending on the Mg compound and alcohol(s) used.

The Group 4-6 transition metal compound is preferably a titanium compound, most preferably a titanium halide such as TiCl ₄ .

The internal donor (ID) used in the deposition of the catalyst used in the present invention is preferably selected from petroleum carboxylic acid (di)esters, 1,3 diesters, derivatives and mixtures thereof. As such, preferred donors are diesters of monounsaturated dicarboxylic acids, in particular esters are esters belonging to the group consisting of malonates, malenates, citraconates, glutarates, cyclohexene 1,2-dicarboxylates and benzoates, and any derivatives and/or mixtures thereof. Preferred examples are, for example, substituted malenates and citraconates, most preferably citraconates.

In the production method using an emulsion, a two-phase liquid-liquid system can be obtained by simple mixing and optionally adding (additional) solvent(s) and additives such as a turbulence minimizing agent (TMA) and/or emulsifying agents and/or emulsion stabilizers , such as surfactants, for example, which are used in a known manner to facilitate the formation and/or stabilization of the emulsion. Preferably, the surfactants are of the acrylic or methacrylic polymer class. Essentially preferred are straight-chain C ₁₂ -C ₂₀ (meth)acrylates such as poly(hexadecyl) methacrylate and poly(octadecyl) methacrylate and mixtures thereof. When a turbulence minimizing agent (TMA) is used, it is preferably selected from α-olefin polymers of α-olefin monomers with 6 to 20 carbon atoms, such as polyoctene, polynonene, polydecene or polydodecene, or mixtures thereof. Most preferred is polydecene.

The particulate solid product produced by precipitation or emulsion solidification may be washed at least once, preferably at least twice, most preferably at least three times with aromatic and/or aliphatic hydrocarbons, preferably toluene, heptane or pentane and/or TiCl4 . Wash solutions may also contain donors and/or Group 13 compounds such as trialkylaluminum compounds, halogenated alkylaluminum compounds. Aluminum compounds can also be added during catalyst synthesis. The catalyst may then be dried using, for example, evaporation or nitrogen purge, or may be suspended in an oily liquid without undergoing any drying step.

The final resulting Ziegler-Natta catalyst is preferably in the form of particles, typically having an average diameter ranging from 5 to 200 microns, preferably from 10 to 100. The particles are compact, have low porosity and a surface area of less than 20 g/m ² , more preferably less than 10 g/ ^m2 . A typical amount of Ti is from 1 to 6 wt.%, Mg from 10 to 20 wt.% and donor from 10 to 40 wt.% of the catalyst composition.

A detailed description of the catalysts is given in WO 2012/007430, EP2610271, EP 261027 and EP 2610272, which are incorporated herein by reference in their entirety.

- 17 043459

Preferably, the Ziegler-Natta catalyst (ZN-C2) is used in combination with an aluminum alkyl compound cocatalyst and optionally external donors.

An external donor (ED) is preferably present as an additional component in the polymerization process of the present invention. Suitable external donors (ED) include certain silanes, ethers, esters, amines, ketones, heterocyclic compounds, and mixtures thereof. As such, the use of silanes is preferred. It is most preferable to use silanes with the general formula:

R ^a pR ^b qSi(OR ^C )(4-pq) where R ^a , R ^b and R ^c denotes a hydrocarbon radical, in particular an alkyl or cycloalkyl group, and where p and q are numbers ranging from 0 to 3, and the sum p + q is equal to or less than 3. R ^a , R ^b and R ^c may be selected independently of each other and may be identical or different. Specific examples of such silanes are (tert-butyl) _2Si ( _OSH3 ) ₂ , (cyclohexyl)(methyl)Si( _OSH3 ) ₂ , (phenyl) _2Si ( _OSH3 ) _2, and (cyclopentyl) _2Si ( _OSH3 ) ₂ , or with the general formula:

Si(OCH2CH3)3(NR ³ R ⁴ ) where R ³ and R ⁴ can represent identical or different hydrocarbon groups with from 1 to 12 carbon atoms.

R ³ and R ⁴ may be independently selected from the group consisting of linear aliphatic hydrocarbon compounds of 1 to 12 atoms, branched aliphatic or aromatic hydrocarbon compounds of 1 to 12 atoms, and cyclic aliphatic hydrocarbon compounds of 1 to 12 atoms. As such, it is preferred that R ³ and R ⁴ be independently selected from the group consisting of methyl, ethyl, n-propyl, n-butyl, octyl, decanyl, isopropyl, isobutyl, isopentyl, t-butyl, tretamyl, neopentyl, cyclopentyl, cyclohexyl, methylcyclopentyl and cycloheptyl.

More preferably, both R ¹ and R ² are identical, even more preferably, both R ³ and R ⁴ are an ethyl group.

In particular, preferred external donors (ED) are a pentyldimethoxysilane donor (D-donor) or a cyclohexylmethyldimethoxysilane donor (C-donor), with the latter being the most preferred.

In addition to the Ziegler-Natta catalyst (ZN-C2) and optional external donor (ED), a cocatalyst can be used. Preferably, the cocatalyst is an IUPAC group 13 compound, for example an organoaluminum compound such as an aluminum compound, such as an aluminum alkyl compound, an aluminum halide compound or an aluminum alkyl halide compound. Accordingly, in one specific embodiment of the present invention, the cocatalyst (Co) is a trialkylaluminum such as triethylaluminum (TEAL), dialkylaluminum chloride or alkylaluminum chloride, or mixtures thereof. In one specific embodiment of the present invention, the cocatalyst (Co) is triethylaluminum (TEAL).

Preferably, the ratio between cocatalyst (Co) and external donor (ED) [Co/ED] and/or the ratio between cocatalyst (Co) and transition metal (TM) [Co/TM] is carefully selected.

Accordingly, (a) the molar ratio of cocatalyst (Co) to external donor (ED) [Co/ED] should be in the range of 5 to 45, preferably in the range of 5 to 35, more preferably in the range of 5 to 25, even more preferably in the range from 4.5 to 25; and optionally (b) the molar ratio of cocatalyst (Co) to titanium compound (TC) [Co/TC] should be in the range of above 80 to 500, preferably in the range of 100 to 350, even more preferably in the range of 120 to 300.

As stated above, the Ziegler-Natta catalyst (ZN-C2) is preferably modified using so-called BNT technology during the above pre-polymerization step to ensure the introduction of a polymeric nucleating agent.

Such a polymeric nucleating agent is a vinyl polymer as defined above, such as a vinyl polymer prepared from monomers with the formula:

CH ₂ =CH-CHR ¹ R ² where R1 and R2 together with the carbon atoms attached to them form an optionally substituted saturated or unsaturated or aromatic ring or fused ring system, where the ring or fused ring group contains from 4 to 20 atoms carbon, preferably a 5 to 12 membered saturated or unsaturated, or aromatic ring, or fused ring system, or independently represents a linear or branched C ₄ -C ₃₀ alkane, a C ₄ -C ₂₀ cycloalkane or a C ₄ -C ₂₀ aromatic ring. Preferably, R1 and R2, together with the C atom attached thereto, form a five- or six-membered saturated or unsaturated or aromatic ring, or independently represent an alkyl group containing from 1 to 4 carbon atoms. Preferably, the vinyl compounds for producing the polymeric nucleating agent used in the present invention are in particular vinyl cycloalkanes, essentially vinyl cyclohexane

- 18 043459 (VCH), vinyl cyclopentane and vinyl-2-methylcyclohexane, 3-methyl-1-butene, 3-ethyl-1-hexene, 3-methyl-1pentene, 4-methyl-1-pentene or mixtures thereof.

As such, the preferred monomer is VCH.

The weight ratio of the vinyl compound to the polymerization catalyst in the polymerization catalyst modification step is preferably 0.3 or more up to 40, such as 0.4 to 20, or more preferably 0.5 to 15, such as 0.5 to 2 ,0.

Polymerization of a vinyl compound, eg VCH, can be carried out in any inert liquid that does not dissolve the resulting polymer (eg polyVCH). It is important to ensure that the viscosity of the final catalyst/polymerized vinyl compound/inert liquid mixture is high enough to prevent precipitation of catalyst particles during storage and transportation.

Elastomeric copolymer of ethylene (E).

The fiber reinforced polypropylene composition (C) of the present invention further contains an elastomeric ethylene copolymer (E).

Preferably, the elastomeric ethylene copolymer (E) is a very low density polyolefin, more preferably a very low density polyolefin, polymerized using a single site metal catalyst, preferably metallocene catalysis.

In a preferred embodiment, the elastomeric ethylene copolymer (E) has a density of less than 0.900 g/cm ³ . More preferably, the density of the elastomeric ethylene copolymer (E) is equal to or less than 0.890 g/cm ³ , even more preferably is in the range of 0.845 to 0.890 g/cm ³ , such as in the range of 0.870 to 0.885 g/cm ³ .

Preferably, the elastomeric ethylene copolymer (E) has a melt flow rate MFR2 (190°C, 2.16 kg) of at least 25 g/10 min, more preferably from 25 to 50 g/10 min, even more preferably from 28 to 40 g /10 min, such as in the range from 29 to 35 g/10 min.

The elastomeric ethylene copolymer (E) contains units derived from ethylene and a C ₄ -C ₁₀ αolefin.

The elastomeric ethylene copolymer (E) contains, preferably consists of units derived from (i) ethylene and (ii) at least another C ₄ -C ₁₀ α-olefin, more preferably units derived from (i) ethylene and (ii) at least another α-olefin selected from the group consisting of 1-butene, 1-pentene, 1-hexene, 1-heptene and 1-octene. As such, preferably the elastomeric ethylene copolymer (E) contains at least units derived from (i) ethylene and (ii) 1-butene or 1-octene.

In one substantially preferred embodiment of the present invention, the elastomeric ethylene copolymer (E) consists of units derived from (i) ethylene and (ii) 1-butene or 1-octene. As such, preferably the elastomeric ethylene copolymer (E) is a copolymer of ethylene and 1-octene.

The comonomer content, such as the C ₄ -C ₂₀ α-olefin content, of the ethylene (E) elastomeric copolymer is in the range of 4 to 25 mol%, more preferably in the range of 5 to 20 mol%, even more preferably in the range of 6 to 12 mol%, such as in the range of 5 to 10 mol%.

In one preferred embodiment of the present invention, the elastomeric ethylene copolymer (E) is produced using at least one metallocene catalyst. The elastomeric ethylene copolymer (E) can also be produced using more than one metallocene catalyst or can be a mixture of multiple elastomers produced using different metallocene catalysts. In some embodiments of the present invention, the elastomeric ethylene copolymer (E) is a substantially linear ethylene polymer (SLEP). SLEPs and other metallocene-catalyzed elastomeric copolymers of ethylene (E) are known from the prior art, for example US 5,272,236. These polymers are also commercially available, for example, as Queo™ plastomers from Borealis, ENGAGE™ plastomer resins from Dow Chemical Co., EXACT™ polymers from Exxon or TAFMER™ polymers from Mitsui, Lucene polymers from LG, Fortify polymers from Sabic or Solumer polymers from SK Chemicals.

Adhesion promoter (AP).

According to the present invention, the fiber-reinforced polypropylene composition (C) further contains an adhesion promoter (AP). The adhesion promoter (AP) is specified as a polar modified polypropylene homo- or copolymer (PM-PP).

Polar modified polypropylene (PM-PP) homo- or copolymer contains a low molecular weight compound with reactive polar groups. Modified propylene homopolymers and copolymers, such as copolymers of propylene and ethylene or with other α-olefins, for example, C ₄ -C ₁₀ α-olefins, are most preferred because they have high compatibility with the propylene polymer (PP) fiber-reinforced polypropylene composition

- 19 043459 (C) according to the present invention.

From a structural point of view, the polar modified polypropylene homo- or copolymer (PM-PP) is preferably selected from graft or block copolymers.

In this context, preference is given to polar modified homo- or copolymers of polypropylene (PM-PP) containing groups derived from polar compounds, in particular selected from the group consisting of acid anhydrides, carboxylic acids, carboxylic acid derivatives, primary and secondary amines, hydroxyl compounds, oxazoline and epoxides, as well as ionic compounds.

Specific examples of these polar compounds are unsaturated cyclic anhydrides and their aliphatic diesters and diacid derivatives. In particular, maleic anhydride and compounds selected from CrGo linear and branched dialkyl maleates, C ₁ -C ₁₀ linear and branched dialkyl fumarates, itaconic anhydride, C ₁ -C ₁₀ linear and branched dialkyl esters of itaconic acid, maleic acid, fumaric acid, itaconic acid and mixtures thereof.

As such, preference is given to using a polypropylene homo- or copolymer grafted with maleic anhydride or acrylic acid as a polar modified polypropylene homo- or copolymer (PM-PP), that is, an adhesion promoter (AP).

The modified polymer, i.e. the adhesion promoter, can be prepared by simply reactively extruding the polymer with, for example, maleic anhydride in the presence of free radical sources (such as organic peroxides), as described, for example, in US 4,506,056, US 4,753,997 or EP 1805238.

Preferred amounts of polar-derived groups in the polar modified polypropylene (PM-PP) homo- or copolymer, ie adhesion promoter (AP), are from 0.5 to 10% by weight. For example, in the range of 0.5 wt% to 8 wt%, preferably in the range of 0.5 to 6 wt%, more preferably in the range of 0.5 wt% to 4 wt%, and most preferably in ranging from 0.5 wt.% to 3.5 wt.%.

Preferred melt flow rates MFR ₂ (190°C) for polar modified polypropylene homo- or copolymer (PM-PP), that is, for adhesion promoter (AP), range from 2 to 500 g/10 min. As such, it is preferable that the polar modified polypropylene homo- or copolymer (PM-PP) has a melt flow rate MFR2 (190° C.) of at least 50 g/10 min.

In one preferred embodiment of the present invention, the adhesion promoter (AP) is a maleic anhydride-modified polypropylene homo- or copolymer and/or an acrylic acid-modified polypropylene homo- or copolymer. Preferably, the adhesion promoter (AP) is a maleic anhydride modified polypropylene homopolymer and/or an acrylic acid modified polypropylene homopolymer and preferably a maleic anhydride modified polypropylene homopolymer. For example, suitable polar modified polypropylene homo- or copolymers (PM-PP) include, for example, maleic anhydride grafted polypropylene homopolymer (PP-g-MAH), acrylic acid grafted polypropylene homopolymer (PP-g-AA).

Fibers (F).

The essential components of the fiber-reinforced polypropylene composition (C) of the present invention are fibers (F).

Preferably, the fibers (F) are selected from the group consisting of glass fiber, metal fiber, mineral fiber, ceramic fiber, carbon fiber and graphite fiber. Fiberglass is preferred.

The fibers (F) used in the present invention may be short fibers (SF), such as short glass fiber (SGF), and/or long fibers (LF), such as long glass fiber (LGF).

According to one embodiment of the present invention, the fibers (F) are short fibers (SF), such as short glass fiber (SGF).

Preferably, short fibers (SF) are selected from the group consisting of glass fiber, metal fiber, mineral fiber, ceramic fiber, carbon fiber and graphite fiber. Fiberglass is preferred. Essentially fiberglass is cut fiberglass, also known as short fiber or chopped strands.

The cut or short fibers (SF) used in the fiber-reinforced polypropylene composition (C) preferably have an average length in the range of 1.0 to 10.0 mm, more preferably in the range of 2.0 to 8.0 mm, even more preferably in the range from 3.0 to 5.0 mm, since in the range from 3.0 to 4.5 mm.

The cut or short fibers (SF) used in the fiber reinforced polypropylene composition (C) preferably have an average diameter of 8 to 20 microns, more preferably 9 to 16 microns, even more preferably 10 to 14 microns, such as 9 to 13 microns.

Preferably, the short fibers (SF) have an aspect ratio of 125 to 650, preferably 150 to 450, more preferably 200 to 470, even more preferably 300 to 430.

The aspect ratio represents the relationship between the average length and the average diameter of the fibers.

According to another embodiment of the present invention, the fibers (F) are long fibers (LF), such as long glass fiber (LGF).

Preferably, long fibers (LF) are selected from the group consisting of glass fiber, metal fiber, mineral fiber, ceramic fiber, carbon fiber and graphite fiber. Fiberglass is preferred. In particular, long fibers (LF) are obtained from glass roving.

The long fibers (LF) used in the fiber-reinforced polypropylene composition (C) preferably have an average diameter of at least 8 µm, more preferably 12 to 25 µm, more preferably 14 to 20 µm, for example 15 to 18 µm.

As stated above, in the case where the fiber-reinforced composition (C) contains long fibers (LF), the fiber-reinforced composition (C) is preferably obtained from a strand of fiber-reinforced polypropylene obtained by contacting fibers (F), such as long fibers (LF ), with a melt of the first polypropylene (PP1) and an adhesion enhancer (AP) and subsequent contacting of the thus obtained impregnated fiber with a melt of the second fraction of propylene polymer (PP) and an elastomeric propylene copolymer (E). Next, the strand thus obtained is cut into granules.

Accordingly, the length of the cut long fibers (LF) in the granules and, consequently, the length of the cut long fibers (LF) in the product obtained using mold casting, preferably injection molding from said granules, depends on the size of the granules. Preferably, the length of the cut long fibers (LF) is in the range of 8.0 to 25.0 mm, more preferably in the range of 9.0 to 18.0 mm, such as in the range of 10.0 to 15.0 mm.

Additives (AD).

In addition to propylene polymer (PP), propylene elastomeric copolymer (E), adhesion promoter (AP) and fibers (F), the fiber reinforced polypropylene composition (C) of the present invention may contain additives (AD). Typical additives include acid scavengers, antioxidants, colorants, light stabilizers, plasticizers, slip agents, scratch resistant agents, dispersants, processing aids, lubricants, pigments, and the like.

Such additives are commercially available and are described, for example, in Plastic Additives Handbook, 6th edition 2009 of Hans Zweifel (pages 1141-1190).

Additionally, as used herein, the term additives (AD) of the present invention also includes within the scope of the concept carrier materials, in particular polymeric carrier materials.

Polymer carrier material.

Preferably, the fiber reinforced polypropylene composition (C) of the present invention does not contain (a) additional polymer(s) other than propylene polymer (PP), propylene elastomeric copolymer (E) and adhesion promoter (AP) in an amount exceeding 15 wt. %, preferably in an amount greater than 10% by weight, more preferably in an amount greater than 9% by weight, based on the total weight of the fiber-reinforced polypropylene composition (C). Any additive carrier material (AD) is calculated not by the amount of polymer compounds, but by the amount of the corresponding additive, as specified in the description of this patent application.

The polymer additive carrier material (AD) provides a polymer carrier to ensure uniform distribution in the fiber reinforced polypropylene composition (C) of the present invention. The polymeric carrier material is not limited to a particular polymer. The polymeric carrier material may be an ethylene homopolymer, an ethylene copolymer derived from ethylene and an α-olefin comonomer, such as a C ₃ -C ₈ α-olefin comonomer, a propylene homopolymer, and/or a propylene copolymer derived from propylene and an α-olefin comonomer, such as ethylene and/or a C ₄ -C ₈ α-olefin comonomer. Preferably, the polymeric carrier material does not contain monomer units derived from styrene or its derivatives.

Additionally, the present invention relates to the following embodiments.

Embodiment of the present invention 1.

An article containing a fiber-reinforced composition (C) comprising:

i) from 30 to 80.0 wt.% propylene polymer (PP), ii) from 2.0 to 12.0 wt.% elastomeric ethylene copolymer (E), where the elastomeric ethylene copolymer (E) has a melt flow rate MFR ( 190°C, 2.16 kg), as determined according to ISO 1133, at least 25.0 g/10 min, iii) from 0.1 to 5.0 wt.% adhesion promoter (AP), and iv) from 10.0 to 70.0 wt.% fiber (F) based on the total weight of the fiber-reinforced composition (C), where the fiber-reinforced composition

- 21 043459 (C) contains propylene polymer (PP) and ethylene elastomeric copolymer (E) in a mass ratio from 85:15 to 99:1.

Embodiment 2 of the present invention.

The article according to Embodiment 1 of the present invention, wherein the elastomeric ethylene copolymer (E) is a copolymer of ethylene and a C ₄ -C ₁₀ α-olefin.

Embodiment 3 of the present invention.

The article of embodiment 1 or 2 of the present invention, wherein the fiber reinforced composition (C) has a melt flow rate MFR2 (230° C., 2.16 kg), as determined according to ISO 1133, less than 100.0 g/10 min.

Embodiment 4 of the present invention.

An article according to any of the preceding embodiments of the present invention, wherein the adhesion promoter (AP) is a polar modified polypropylene (PM-PP) homo- or copolymer of maleic anhydride grafted propylene with a melt flow rate MFR (190°C, 2.16 kg), as determined according to ISO 1133, at least 50.0 g/10 min.

Embodiment of the present invention 5.

The article according to any of the preceding embodiments of the present fiber-reinforced composition (C) contains fibers (F) and ethylene copolymer (E) in a ratio of 95:5 to 70:30.

Embodiment 6 of the present invention.

The product according to any of the preceding embodiments of the present elastomeric ethylene copolymer (E) has:

a) comonomer content from 2.0 to 25.0 mol.% and/or

b) density less than 0.900 g/cm ³ .

Embodiment of the present invention 7.

The article according to any of the preceding embodiments of the present elastomeric ethylene copolymer (E) is a copolymer of ethylene and 1-octene.

inventions, where in mass invention, where inventions, where

Embodiment of the present invention 8.

The article according to any of the preceding embodiments, the propylene polymer (PP), is a homopolymer of propylene.

Embodiment of the present invention 9.

The article according to any of the preceding embodiments of the propylene polymer (PP) is at least bimodal.

Embodiment of the present invention 10.

An article according to any of the preceding embodiments of the present present invention, wherein the invention, wherein the invention, wherein the fibers (F) are selected from the group consisting of glass fiber, metal fiber, ceramic fiber, carbon fiber and graphite fiber.

Embodiment of the present invention 11.

An article according to any of the preceding embodiments of the present invention, wherein the fibers (F) are short fibers (SF) and/or long fibers (LF), preferably short glass fiber (SGF) and/or long glass fiber (LGF).

Embodiment of the present invention 12.

An article according to any of the preceding embodiments of the present invention, comprising at least 80.0% by weight of the fiber-reinforced composition (C) based on the total weight of the article.

The product according to any of the preceding embodiments of the present invention, wherein said product is a molded product, is preferably an injection molded product.

The present invention will now be described in more detail with reference to illustrative but non-limiting examples.

Examples

1. Measurement methods.

MFR ₂ (230°C) as measured according to ISO 1133 (230°C, load 2.16 kg). MFR ₂ (190°C) as measured according to ISO 1133 (190°C, 2.16 kg load). The melt flow rate MFR2 (230°C) of propylene polymer (PP) is calculated according to the equation (I) log (PP) = w(PPl) logMFJ?(PPl) w(PP2) logMFR(PP2) + w(PP3) log MFP( PP3) (I), where w(PP1) is the mass of the fraction of the first propylene polymer (PP1), w(PP2) is the mass of the fraction of the second propylene polymer (PP2), w(PP3) is the mass of the fraction of the third propylene polymer (PP3),

MFR(PP1) - melt flow rate MFR2 (230°C, 2.16 kg) in g/10 min of the first propylene polymer (PP1),

- 22 043459

MFR(PP2) - melt flow rate MFR2 (230°C, 2.16 kg) in g/10 min of the second propylene polymer (PP2),

MFR(PP3) is the melt flow rate of MFR2 (230°C, 2.16 kg) in g/10 min of the third propylene polymer (PP3), and

MFR(PP) - melt flow rate MFR2 (230°C, 2.16 kg) in g/10 min of propylene polymer (PP).

Quantitative analysis of microstructure using NMR spectroscopy.

Quantitative nuclear magnetic resonance (NMR) spectroscopy is used to estimate the comonomer content of polymers and the comonomer sequence distribution in polymers. Quantitative analysis ^{of the 13} C{1H} NMR spectrum was recorded in solution using a Bruker Advance III 400 NMR spectrometer operating at frequencies ranging from 400.15 to 100.62 MHz for 1H and ¹³ C, respectively. The entire spectrum is recorded using a ¹³ C optimized 10 mm linear sensor over an extended temperature range at 125° C using nitrogen gas throughout the pneumatics. About 200 mg of the material was dissolved in 3 ml of 1,2 tetrachloroethane-d ₂ (TCE-d 2 ) with chromium (III)-acetylacetonate (Cr(acac) ₃ ) to obtain a 65 mM solution of the relaxant in the solvent (Singh, G. , Kothari, A., Gupta, V., Polymer Testing 28 5 (2009), 475). To ensure solution homogeneity, after obtaining the initial sample in the thermal block, the ampoule for NMR spectroscopy is additionally heated in an oven with a circular rotating hearth for at least 1 hour. When installed in a magnet, the ampoule is exposed to 10 Hz. This design was chosen primarily due to the need for high resolution quantitative analysis for accurate quantification of ethylene content. Creates a standard single-pulse excitation without NOE at an optimized tilt angle with a 1 second cycle repeat delay and a two-level WALTZ16 decoupling circuit (Zhou, Z., Kuemmerle, R., Qiu, X., Redwine, D., Cong, R., Taha, A., Baugh, D. Winniford, V., J. Mag. Reson. 187 (2007) 225; Busico, V., Carbonniere, P., Cipullo, R., Pellecchia, R., Severn, J., Talarico , G., Macromol. Rapid Commun. 2007, 28, 11289). In total, the spectrum required 6144 (6k) pulses.

A quantitative analysis was carried out based on ^{the 13} C{1H} NMR spectrum with a certain average value and the corresponding quantitative values were determined using the integral using special computer programs. For ethylene-propylene copolymers, all chemical shifts indirectly point to the central methylene group of the ethylene block (EEE) at 30.00 ppm using solvent chemical shift. This approach allows comparison with a standard even in the absence of a structural unit. Characteristic signals corresponding to the introduction of ethylene were observed Cheng, HN, Macromolecules 17 (1984), 1950).

For propylene homopolymers, all chemical shifts essentially point to the methyl isotactic pentad (mmmm) at 21.85 ppm.

Characteristic signals corresponding to 2,1 erythro regiodefects were observed (given in L. Resconi, L. Cavallo, A. Fait, F. Piemontesi, Chem. Rev. 2000, 100 (4), 1253, in Cheng, H. N., Macromolecules 1984, 17, 1950, and in W-J. Wang and S. Zhu, Macromolecules 2000, 33 1157), requires correction due to the influence of regiodefects on certain properties. No characteristic signals corresponding to other types of regional defects were observed.

The regularity of the molecular structure distribution is quantified by methyl region integration ranging from 23.6 to 19.7 ppm, corrected for any regions not associated with the stereosequence of interest (Busico, V., Cipullo, R., Prog. Polym. Sci. 26 (2001) 443; Busico, V., Cipullo, R., Monaco, G., Vacatello, M., Segre, A. L., Macromolecules 30 (1997) 6251).

In particular, the effect of regiodefects and comonomer on the quantitative analysis of the regularity of the molecular structure distribution is corrected by subtracting the integrals of the representative regiodefect and comonomer from the specific region of the stereosequence integral.

Isotacticity was determined by the level of pentads and reported as the percentage of isotactic pentad sequences (mmm) from all pentad sequences:

[mmmm] % = 100*(mmmm/sum of all pentads)

The presence of 2.1 erythro regiodefects is indicated by the presence of two methyl areas at 17.7 and 17.2 ppm and is confirmed by other characteristic areas.

No characteristic signals corresponding to other types of regiodefects were observed (Resconi, L., Cavallo, L., Fait, A., Piemontesi, F., Chem. Rev. 2000, 100, 1253).

Quantitative analysis of 2.1 erythroregiodefects was carried out using the average integral of two characteristic methyl sites of 17.7 and 17.2 ppm:

P21e=(Ie6+Ie8)/2

Quantitative analysis of 1,2 primary insertion propene is performed based on the methyl region, correcting for regions included in this region that are not associated with the primary insertion, and regions of the primary insertion excluded from this region:

^P 12=ICH3 ^+P 12e

The total amount of propene is quantified as the sum of the initially inserted propene and all other regional defects present:

- 23 043459

Ptotal=P12+P21e

The molar percentage of 2.1 erythrioregiodefects is quantified from the total propene content:

[21e] mol.% = 100*(P21e/Ptotal)

Characteristic signals for copolymers corresponding to the introduction of ethylene were observed (Cheng, H. N., Macromolecules 17 (1984), 1950).

Regional defects have also been observed (Resconi, L., Cavallo, L., Fait, A., Piemontesi, F., Chem. Rev. 2000, 100, 1253; Wang, W-J., Zhu, S., Macromolecules 33 (2000), 1157; Cheng, H. N., Macromolecules 17 (1984), 1950), requires correction of the effect of such defects on the comonomer content.

The comonomer fraction was quantified using the method of Wang et. Al. (Wang, W. J., Zhu, S., Macromolecules 33 (2000), 1157) by integrating multiple signals from the entire spectral region of ^{the 13} C{1H} spectrum obtained under specified conditions. This method was chosen for its accuracy, reliability and ability, if necessary, to explain the presence of regional defects. The integral regions are slightly adjusted to improve applicability to a wide range of comonomer contents.

For systems where only block ethylene is observed in PPEPP sequences, the method of Wang et. al., modified to reduce the influence of regions of non-zero integrals that are known to be missing. This approach reduces the overestimation of ethylene content for such a system and reduces the number of areas used to determine the absolute ethylene content:

E=0.5(sββ+sβγ+Sβδ+0.5(Sαβ+Sαγ))

When using this range of domains, the corresponding integral equation becomes: E=0.5(Ih+Ig+0.5(Ic+Id))

The same notation is used as in the paper by Wang et. al. (Wang, W-J., Zhu, S., Macromolecules 33 (2000), 1157). The equations used to determine the absolute propylene content were not modified.

The molar percentage of comonomer introduced into the polymer is calculated from the molar fraction according to:

E [mol.%]=100*fE

The mass percentage of comonomer introduced into the polymer is calculated from the molar fraction according to:

E [wt.%]=100*(fE*28.05)/((fE*28.05)+((1-fE)*42.08))

The comonomer sequence distribution in triads was determined using the method of Kakugo et al. (Kakugo, M., Naito, Y., Mizunuma, K., Miyatake, T. Macromolecules 15 (1982) 1150) by integrating multiple signals from the entire spectral region of ^{the 13} C{1H} spectrum obtained under specified conditions. This method was chosen for its reliability. The integral regions are slightly adjusted to improve applicability to a wide range of comonomer contents.

Number average molecular weight (Mn), weight average molecular weight (Mw) and molecular weight distribution (MWD).

Average molecular weights (Mw, Mn), molecular weight distribution (MWD), i.e. Mw/Mn (where Mn represents the number average molecular weight and Mw represents the mass average molecular weight) are determined using gel permeation chromatography (GPC), according to ISO 16014-4 2003 and ASTM D 6474-99. A PolymerChar GPC device equipped with an infrared (IR) detector was used with 3xOlexis and 1xOlexis guard columns from Polymer Laboratories and 1,2,4-trichlorobenzene (TCB, stabilized with 250 mg/L 2,6-ditertbutyl-4methylphenol) as solvent at temperature 160°C and constant mass flow equal to 1 ml/min. For analysis, 200 μl of sample solution was injected. The column set was calibrated using a universal calibration (according to ISO 16014-2:2003) with at least 15 polystyrene (PS) standards with a narrow MWD ranging from 0.5 kg/mol to 11500 kg/mol. For PS, PE and PP, Mark Houwink constants were used as given in ASTM D 6474-99. All samples were prepared by dissolving 0.5-9.0 mg of polymer in 8 ml (at 160°C) stabilized with TCB (matching the mobile phase), and incubating for PP 2.5 hours or PE 3 hours maximum. The samples were subjected to continuous gentle shaking at 160°C until placed in the sample inlet of the GPC device.

DSC analysis, melting point (Tm) and heat of fusion (Hf), crystallization temperature (Tc) and enthalpy of fusion (H m): measurements were carried out using a TA Instrument Q200 for differential scanning calorimetry (DSC) on samples ranging from 5 to 7 mg in size . DSC was carried out according to ISO 11357/part 3/method C2 in a heat/cool/heat cycle at a scan rate of 10°C/min at temperatures ranging from -30 to +225°C. The crystallization temperature (Tc) and crystallization enthalpy (Hc) were determined in the cooling stage, while the melting temperature (Tm) and melting enthalpy (Hm) were determined in the second heating stage. Crystallinity was calculated from the enthalpy of fusion, assuming Hm to be 209 J/g for fully crystalline polypropylene (see Brandrup, J., Immergut, E. H., Eds. Polymer Handbook, 3rd ed. Wiley, New York, 1989;

Chapter 3).

The glass transition temperature Tg was determined using dynamic mechanical thermal analysis according to ISO 6721-7. The measurements were carried out in the torsional vibration mode using samples obtained by injection molding (40x10x1 mm ³ ), from -100°C to +150°C at a heating rate of 2°C/min and a frequency of 1 Hz.

The comonomer content of the elastomer (E) is determined using a known Fourier transform infrared spectroscopy (FTIR) method, calibrated against ¹³ C-NMR results using a Nicolet Magna 550 IR spectrometer with Nicolet Omnic FTIR software. Films with a thickness of about 250 µm are obtained from injection molded samples. Similar films are prepared from calibration samples with known comonomer content. The comonomer content is determined by a spectral window with a wave number ranging from 1430 to 1100 cm ^-1 . Absorbance is measured as the highest peak, choosing the so-called short or long base or both. The short base is in the range of 1410-1320 cm ^-1 , passing through the minimum points, and the long base is in the range of 1410-1220 cm ^-1 . Calibration must be carried out specifically for each base. Also, the comonomer content of the unknown sample should be within the comonomer content of the calibration samples.

Ash content is measured according to ISO 3451-1 (1997).

Density is measured according to ISO 1183-187. The sample is obtained by injection molding according to ISO 1872-2:2007.

Charpy notched impact strength and Charpy unnotched impact strength are determined according to ISO 179/leA and ISO 179-1/leU at a temperature of 23°C using an injection molded test piece of size (80x10x4 mm ³ ) obtained according to ISO 19069-2 with modifications listed below.

Tensile mechanical properties are determined using injection molded dog bone specimens according to ISO 19069-2.

The tensile modulus is determined according to ISO 527-1A at 1 mm/min and 23°C. A speed of 50 mm/min was used to determine tensile yield and elongation at yield.

Drop weight test: Puncture energy, maximum force value and puncture deflection are determined by performing a drop weight test in accordance with ISO 6603-2 using 60x60x3mm injection molded plates produced in accordance with ISO 19069-2, with the modifications given below, and test speed 4.4 m/s. The indicated puncture energy is obtained by using the integral of the fracture energy curve as measured at +23°C and 30°C.

The average fiber diameter is determined according to ISO 1888:2006(E), Method B, using a microscope magnification power of 1000.

2. Examples.

A. Materials used.

PP1 is a commercial propylene homopolymer with a high flow rate HL504FB from Borealis AG with a melt flow rate MFR ₂ (230°C) 450 g/10 min and a glass transition temperature Tg +0°C.

PP2 is a commercial propylene homopolymer HJ120UB from Borealis AG with a melt flow rate MFR2 (230°C) of 75 g/10 min, a density of 905 kg/m ³ and a glass transition temperature Tg +2°C.

PP3 is a commercial propylene homopolymer HF955MO from Borealis AG with a melt flow rate MFR2 (230°C) 20 g/10 min, density 908 kg/m ³ and glass transition temperature Tg +4°C. Propylene homopolymer HF955MO α-nucleated with polyvinyl cyclohexane (polyVCH).

PP4 is a commercial propylene homopolymer HK060UB from Borealis AG with a melt flow rate MFR2 (230°C) of 125 g/10 min.

E is a commercial ethylene-octene copolymer Queo8230 from Borealis with a density of 0.882 g/cm ³ , a melt flow rate MFR2 (190°C) of 30.0 g/10 min and a 1-octene content of 7.5 mol.%.

SF is a commercial product ECS 03 T-480H from Nippon Electric Glass Co., Ltd. with a thread diameter of 10.5 microns and a strand length of 3 mm.

LF - commercial glass roving Performax SE4849 from Owens Coining.

AP - adhesion enhancer SCONA TPPP 9012 GA from Scona representing polypropylene functionalized with maleic anhydride, with a maleic anhydride content of 1.4 wt.% and MFR (190°C) above 50 g/10 min.

Pigment 1 - masterbatch containing 1 wt.% Remafin Schwarz P-AP (MP 99-BLACK 7-PP-from 30) from Clariant.

Pigment 2 - black pigment PCD PP-3719 BMB PPINJ PB25/1250 (MB 990 -black 7-PP-40).

AD - a composition containing 1 part by weight tris-(2,4-di-t-butylphenyl) phosphite (Kinox-68-G from HPL Additives) and 2 parts by weight pentaerythrityl-tetrakis(3-(3',5' -di-tert.butyl-4-hydroxyphenyl)

- 25 043459 propionate (Irganox 1010FF from BASF).

B. Compositions reinforced with short fibers.

The following examples of the present invention IE1-IE5 and comparative examples CE1 and CE2 were produced by compounding in a twin screw extruder with co-rotating screws (ZSK 40 from Coperion) with an L/D ratio of 43. The following process parameters were used: throughput 100 kg/h screw speed 100 - 150 rpm cylinder temperature 220-250°C, increasing from the feed zone and decreasing again to the matrix plate matrix plate with a hole diameter of 4 mm and 3 strands (threads) Polymer and additives other than short fibers are fed into the extruder and the mixed melt are fed into the 2nd cylinder. The first mixing zone for mixing the polymer and additives is located between the 3rd and 5th cylinders. Short fibers are fed into the 6th cylinder using a side feeder. The second mixing zone for dispersing the glass fiber is located between the 7th and 12th cylinders. The composition and properties are given in table. 1 and 2.

Table 1

Composition and properties of examples of the present invention and comparative examples

CE1 SE2 IE1 IE2 IE3 IE4 IE5 PP1 [mass%] 10.0 6.7 8.9 9.4 8.9 8.3 7.8 PP2 [mass%] 25.0 16.6 22.2 23.7 22.2 20.9 19.4 RRZ [mass%] 10.0 6.7 8.9 9.4 8.9 8.3 7.8 E [mass%] - 15.0 5.0 2.5 5.0 7.5 10.0 SF [mass%] 50.0 50.0 50.0 50.0 50.0 50.0 50.0 AR [mass%] 2.0 2.0 2.0 2.0 2.0 2.0 2.0 Pigment [mass%] 1.0 1.0 1.0 1.0 1.0 1.0 1.0 AD [mass%] 2.0 2.0 2.0 2.0 2.0 2.0 2.0

table 2

Properties of Examples of the Present Invention and Comparative Examples

CE1 SE2 IE1 IE2 IE3 IE4 IE5 Content ash [mass%] 49.9 50.9 49.1 49.4 49.8 49.6 49.8 MFR [g/10 minutes] 2.81 4.04 3.04 2.14 2.45 2.33 2.29 Tensile modulus [MPa] 13016 10097 12275 12608 12210 11820 11350 Tensile strength [MPa] 147.27 97.84 141.60 154.94 145.19 137.17 127.06 Relate- telial elongation at [%] 2.16 2.41 2.32 2.29 2.46 2.62 2.70

- 26 043459

tensile strength at gap Breaking tensile stress [MPa] 147.27 97.70 141.38 154.94 145.14 136.92 126.77 Relate- telial elongation at break [%] 2.16 2.44 2.33 2.29 2.45 2.57 2.60 Charly Notched Impact Strength (23°C) [kJ/ ^m2 ] 12.72 16.81 16.86 12.59 14.10 13.56 14.37 Impact strength without notch Charlie (23 °C) [kJ/ ^m2 ] 62.58 55.41 63.16 60.37 63.38 61.55 60.01 Maximum force value [N] 1789 1681 1955 2102 2072 2186 2039 Bending at maximum force [mm] 4.91 5.71 6.17 4.79 4.73 5.42 5.04 Energy at maximum force value [J] 5.58 6.39 8.02 6.23 6.15 7.57 6.43 Bending at puncture [mm] 5.76 7.70 7.35 5.62 6.02 6.49 6.53 Puncture energy [J] 6.78 9.10 9.91 7.67 8.40 9.60 8.91

C. Compositions reinforced with long fibers.

The compositions according to examples CE3, CE4 and IE6 - IE8 were obtained by impregnating glass rovings (LF) using an impregnation tool according to EP 0 397 505 B1 with a composition containing a commercial homopolymer of propylene with a high melt flow rate HL504FB from Borealis AG with a melt flow rate MFR2 (230° C) 450 g/10 min (PP1) and adhesion promoter (AP) (SCONA TPPP 9012 GA from Scona). Impregnated rovings were combined and processed using a coating matrix of a composition containing commercial propylene homopolymer HJ120UB from Borealis AG with a melt flow rate MFR2 (230°C) 75 g/10 min (PP2), commercial propylene homopolymer HF955MO from Borealis AG with a melt flow rate MFR2 (230°C) 20 g/10 min (PP3) and a commercial ethylene-octene copolymer Queo8230 from Borealis with a density of 0.885 g/cm ³ (E) in a mass ratio according to table. 2. The strands are produced at a speed of 40 m/min and immediately after production are pulled through a water bath about 8 m long. The coated strands are then dried for 5 m. The dried strands are then processed using a garnuler, where they are cut into granules 15 m long mm.

A composition following example CE5 was obtained by coating glass rovings (LF) from a composition containing a commercial propylene homopolymer HK060UB from Borealis AG with a melt flow rate MFR2 (230°C) 125 g/10 min (PP3), adhesion enhancer (AP) (SCONA TPPP 9012 GA from Scona) and a commercial ethylene-octene copolymer Queo8230 from Borealis with a density of 0.880 g/cm ³ (E) in a mass ratio according to table. 2. The strands were subjected to the above technological processing.

- 27 043459

Compositions according to examples CE6, CE7 and IE9-IE12 were obtained similarly to compositions according to CE3, CE4 and

IE6 - IE8 with the difference that the above propylene polymers and glass rovings were used in a mass ratio according to table. 3 and the strands were obtained at a speed of 65 m/min.

The properties of the composition of the present invention and comparative examples are shown in table. 3 and 4.

Long fiber reinforced composite samples were tested to determine Charpy notched and Charpy unnotched impact strength, tensile mechanical properties and drop weight impact testing as above in accordance with ISO 19069-2 with the following modifications.

Flow front speed: 100 mm/s.

Mass temperature: 250°C.

Hydraulic back pressure: 1 bar.

Pressure application time: from 30 s.

Cooling time: 25 s.

- 28 043459

Table 3

Composition and properties of fiber-reinforced compositions containing 20.0 wt.% long fibers

SEZ CE4 CE5 IE6 IE7 IE8 PP1 [mass%] 34.80 27.30 33.55 32.30 29.80 PP2 [mass%] 34.80 27.30 33.55 32.30 29.80 RRZ [mass%] 8.0 8.0 8.00 8.00 8.00 PP4 [mass%] 65.25 E [mass%] 15.0 10.0 2.50 5.00 10.0 LF [mass%] 20.0 20.0 22.0 20.0 20.0 20.0 AR [mass%] 1.04 1.04 1.50 1.04 1.04 1.04 Pigment 1 [mass%] 0.64 0.64 0.64 0.64 0.64 Pigment 2 [mass%] 0.50 AD [mass%] 0.72 0.72 0.75 0.72 0.72 0.72 Content ash [mass%] 19.4 19.5 21.7 19.7 19.6 19.5 Tensile modulus of elasticity!) [MPa] 5712 5021 5350 5678 5543 5367 Tensile strength!) [MPa] 114.4 103.6 103.0 115.2 115.3 112.1 Relate- telial elongation at limit tensile strength!) [%] 2.60 2.75 2.56 2.65 2.75 2.73 Breaking tensile stress!) [MPa] 114.39 103.61 103.0 115.16 115.34 112.14 Relate- telial elongation at [%] 2.60 2.75 2.56 2.65 2.74 2.73

- 29 043459

break!) Notched impact strength Charlie (23 °C) 1) [kJ/ ^m2 ] 14.31 18.79 16.6 13.61 14.14 16.43 Impact strength without notch Charlie (23 °C) 1) [kJ/ ^m2 ] 43.88 59.75 52.3 51.74 57.09 55.05 Maximum force value!) [N] 1748.4 1769.6 But. 1735.7 1874.0 1794.4 Bending at maximum force value!) [mm] 5.24 6.31 But. 5.23 6.08 5.95 Energy at maximum force!) [J] 5.21 7.44 But. 5.39 6.92 6.99 Bending at puncture!) [mm] 7.59 8.75 But. 7.01 8.91 8.73 Puncture energy!) [J] 8.32 10.8 9.96 7.75 10.6 10.65

1) determined on test samples obtained in accordance with ISO 19069-2 with the above modifications. But. - do not define

- 30 043459

Table 4

Composition and properties of fiber-reinforced compositions containing 40.0 wt.% long fibers

CE6 CE7 IE9 SHYU IE11 IE12 PP1 [mass%] 25.51 18.01 24.26 23.01 21.76 20.51 PP2 [mass%] 25.51 18.01 24.26 23.01 21.76 20.51 RRZ [mass%] 6.0 6.0 6.0 6.0 6.0 6.0 E [mass%] 15.0 2.50 5.0 7.5 10.0 LF [mass%] 40.0 40.0 40.0 40.0 40.0 40.0 AR [mass%] 1.97 1.97 1.97 1.97 1.97 1.97 Pigment 1 [mass%] 0.47 0.47 0.47 0.47 0.47 0.47 AD [mass%] 0.54 0.54 0.54 0.54 0.54 0.54 Content ash [mass%] 39.9 40.3 39.7 39.8 39.8 39.9 Tensile modulus of elasticity!) [MPa] 10559 9367 10337 10143 10103 9984 Tensile strength!) [MPa] 175.2 144.9 174.2 167.3 165.8 161.5 Relate- telial elongation at limit tensile strength!) [%] 2.20 2.28 2.25 2.24 2.28 2.29 Breaking tensile stress!) [MPa] 175.2 144.9 174.2 167.3 165.8 161.5 Relate- telial elongation at break!) [%] 2.20 2.28 2.25 2.24 2.28 2.29 Impact strength with Charlie notch (23 °C) 1) [kJ/ ^m2 ] 26.55 29.28 29.76 32.04 30.21 33.53 Percussion [kJ/ ^m2 ] 83.6 74.8 80.49 82.34 80.26 76.87

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Claims (11)

strength without cutting Charlie (23 °C) 1) Maximum force value1) [N] 2498.0 2568.3 2704.2 2688.8 2659.2 2693.5 Bending at maximum force value1) [mm] 4.67 5.24 5.18 5.66 5.53 5.67 Energy at maximum force1) [J] 7.02 8.26 8.56 9.72 9.33 9.67 Bending at puncture1) [mm] 7.58 9.88 8.49 8.60 9.19 9.50 Puncture energy!) [J] 12.7 17.9 15.55 15.93 17.33 17.82 1) determined on test samples obtained in accordance with ISO 19069-2 with the above modifications As can be seen from table. 2-4, the composition of Comparative Examples containing 15.0 wt.% elastomeric compound has high puncture energy and therefore excellent impact properties, but the tensile modulus is significantly reduced compared to Comparative Examples, which contain the same amount of fibers , but do not contain an elastomeric compound. The compositions of the examples of the present invention containing from 2.5 to 10.0 wt.% elastomeric compound also showed high puncture energies, but the tensile modulus remained at a high level. Consequently, a good balance between rigidity and impact resistance is achieved. CLAIM 1. An injection molded product for the automotive industry comprising a fiber-reinforced composition (C) comprising: i) from 20.0 to 80.0 wt.% propylene polymer (PP), which is at least bimodal and has a melt flow rate MFR ₂ (230°C, 2.16 kg), as determined according to ISO 1133 , ranging from 30 to 250 g/10 min, ii) from 2.0 to 12.0 wt.% elastomeric ethylene copolymer (E), representing a copolymer of ethylene and C ₄ -C ₁₀ α-olefin, having a melt flow rate of MFR2 (190°C, 2.16 kg), as determined according to ISO 1133, at least 25.0 g/10 min, iii) from 0.1 to 5.0 wt.% adhesion promoter (AP), which is a polar modified homo- or copolymer of propylene, and iv) from 10.0 to 70.0 wt.% fibers (F) based on the total weight of the fiber-reinforced composition (C), wherein the fiber-reinforced composition (C) contains propylene polymer (PP) and elastomeric copolymer of ethylene (E) in a mass ratio from 85:15 to 99:1. 2. The article according to claim 1, wherein the fiber reinforced composition (C) has a melt flow rate MFR ₂ (230°C, 2.16 kg), as determined according to ISO 1133, less than 100.0 g/10 min. 3. The product according to claim 1 or 2, where the adhesion promoter (AP) is a polar modified polypropylene (PM-PP), which is a homo- or copolymer of propylene grafted with maleic anhydride, with a melt flow rate MFR (190 ° C, 2.16 kg), as determined according to ISO 1133, at least 50.0 g/10 min. 4. An article according to any of the preceding claims, wherein the fiber-reinforced composition (C) - 32 043459 contains fibers (F) and ethylene copolymer (E) in a mass ratio from 95:5 to 70:30. 5. An article according to any one of the preceding claims, wherein the elastomeric ethylene copolymer (E) has a comonomer content of from 2.0 to 25.0 mol%. 6. The product according to any of the preceding claims, wherein the elastomeric ethylene copolymer (E) has a density of less than 0.900 g/cm ³ . 7. An article according to any one of the preceding claims, wherein the elastomeric ethylene copolymer (E) is a copolymer of ethylene and 1-octene. 8. An article according to any one of the preceding claims, wherein the propylene polymer (PP) is a homopolymer of propylene. 9. An article according to any one of the preceding claims, wherein the fibers (F) are selected from the group consisting of glass fiber, metal fiber, ceramic fiber, carbon fiber and graphite fiber. 10. An article according to any one of the preceding claims, wherein the fibers (F) are short fibers (SF) having an average length of from 2.0 to 8.0 mm and/or long fibers (LF) having a length of from 9.0 to 8.0 mm 18.0 mm, preferably short glass fiber (SGF) and/or long glass fiber (LGF). 11. An article according to any one of the preceding claims, comprising at least 80.0% by weight of the fiber-reinforced composition (C) based on the total weight of the article. Eurasian Patent Organization, EAPO Russia, 109012, Moscow, Maly Cherkassky lane, 2