GB2568909A

GB2568909A - Polypropylene composition with high scratch resistance

Info

Publication number: GB2568909A
Application number: GB1719913.4A
Authority: GB
Inventors: Liu Yi; Kastner Erwin; Dou Qizheng; Romina Albunia Alexandra
Original assignee: Borealis AG
Current assignee: Borealis AG
Priority date: 2017-11-30
Filing date: 2017-11-30
Publication date: 2019-06-05
Also published as: GB201719913D0

Abstract

Disclosed is a polypropylene composition (C) comprising: a first heterophasic propylene copolymer (HEC01); a second heterophasic propylene copolymer (HECO2); an ultra-high molecular weight polyethylene (UHMWPE) having a nominal viscosity molecular weight of at least 500 kg.mol-1; and an inorganic filler (F) as well as an article (preferably an automotive article) comprising said polypropylene composition (C). HECO1 has a xylene soluble fraction (XCS) of at least 25.05 wt.% and comprises a matrix being a first propylene polymer (M1) and a first elastomeric propylene copolymer (E1) dispersed in said matric. HECO2 has a xylene cold-soluble fraction (XCS) of below 25.0 wt.% and comprises a second propylene polymer (M2) and a second elastomeric propylene copolymer (E2) dispersed within M2. Preferably, the inorganic filler is talc. Preferably, HECO1 and/or HECO2 are copolymers of propylene and ethylene. Preferably, the UHMWPE is an ethylene homopolymer.

Description

The present invention is directed to a polypropylene composition (C) comprising a first heterophasic propylene copolymer (HECO1), a second heterophasic propylene copolymer (HECO2), an ultra high molecular weight polyethylene (UHMWPE) and an inorganic filler (F) as well as an article comprising said polypropylene composition (C).

Polypropylene materials are widely used in the field of automotive parts. Especially with regard to visible automotive parts, it is desired that the applied polypropylene is featured by a high scratch resistance. So far, high density polyethylenes (HDPE) are added to the polypropylene compositions in order to improve the scratch resistance. Following this approach, however, an increased amount of flow marks occurs during injection moulding of the polypropylene composition at short injection times.

Thus, there is a need in the art for a polypropylene composition which can be injection moulded at short injection times to obtain an article showing high scratch resistance accompanied by an excellent surface quality.

Accordingly, it is an object of the present invention to provide a polypropylene composition featured by a high scratch resistance as well as a reduced amount of flow marks.

Therefore, the present invention is directed to a polypropylene composition (C) comprising

i) a first heterophasic propylene copolymer (HECO1) having a xylene soluble fraction (XCS) of at least 25.0 wt.-%, comprising

a) a matrix being a first propylene polymer (Ml) and

b) a first elastomeric propylene copolymer (El) dispersed in said matrix, ii) a second heterophasic propylene copolymer (HECO2) having a xylene soluble fraction (XCS) below 25.0 wt.-%, comprising

a) a matrix being a second propylene polymer (M2) and

b) a second elastomeric propylene copolymer (E2) dispersed in said matrix, iii) an ultra high molecular weight polyethylene (UHMWPE) being a polyethylene having a nominal viscosity molecular weight Mv of at least 500 kg/mol, and iv) an inorganic filler (F).

It was surprisingly found that replacing the high density polyethylene (HDPE) which has been added so far in order to increase the scratch resistance by an ultra high molecular weight polyethylene (UHMWPE) leads to a reduced amount of tiger stripes while the scratch resistance remains on a high level.

According to one embodiment of the present invention, the ultra high molecular weight polyethylene (UHMWPE) is an ethylene homopolymer.

According to a further embodiment of the present invention, the ultra high molecular weight polyethylene (UHMWPE) has

i) a density of at least 920 g/cm³, and/or ii) a melt flow rate MFR21 (190 °C, 21.6 kg) below 2.0 g/10 min.

According to another embodiment of the present invention, the polypropylene composition (C) has a melt flow rate MFR (190 °C, 2.16 kg) measured according to ISO 1133 in the range of 3.0 to 25.0 g/10 min.

It is especially preferred that the polypropylene composition (C) comprises

a) 40.0 to 60.0 wt.-% of the first heterophasic propylene copolymer (HECO1),

b) 10.0 to 25.0 wt.-% of the second heterophasic propylene copolymer (HECO2),

c) 5.0 to 17.0 wt.-% of the ultra high molecular weight polyethylene (UHMWPE), and

d) 7.0 to 20.0 wt.-% of the inorganic filler (F),

-3 based on the overall weight of the polypropylene composition (C).

According to one embodiment of the present invention, the first heterophasic propylene copolymer (HECO1) and/or the second heterophasic propylene copolymer (HECO2) are copolymers of propylene and ethylene.

According to another embodiment of the present invention, the first heterophasic propylene copolymer (HECO1) has

i) a melt flow rate MFR (230 °C, 2.16 kg) in the range of 10.0 to 30.0 g/10 min and/or ii) a comonomer content in the range of 5.0 to 35.0 mol-%.

According to still another embodiment of the present invention, the xylene soluble fraction (XCS) of the first heterophasic propylene copolymer (HECO1) has

i) a comonomer content above 30 mol.-%, and/or ii) an intrinsic viscosity (IV) measured according to ISO 1628/1 (at 135 °C in decalin) in the range of 1.0 to 4.5 dl/g.

According to one embodiment of the present invention, the matrix of the first heterophasic propylene copolymer (HECO1), i.e. the first propylene polymer (Ml), has a melt flow rate MFR (230 °C, 2.16 kg) measured according to ISO 1133 above 50.0 g/10 min.

According to a further embodiment of the present invention, the second heterophasic propylene copolymer (HECO2) has

i) a melt flow rate MFR (230 °C, 2.16 kg) in the range of 10.0 to 30.0 g/10 min and/or ii) a comonomer content in the range of 4.0 to 17.0 mol-%.

According to one embodiment of the present invention, the xylene soluble fraction (XCS) of the second heterophasic propylene copolymer (HECO2) has

i) a comonomer content above 35 mol.-%, and/or ii) an intrinsic viscosity (IV) measured according to ISO 1628/1 (at 135 °C in decalin) in the range of 1.3 to 3.3 dl/g.

According to another embodiment of the present invention, the matrix of the second heterophasic propylene copolymer (HECO2), i.e. the second propylene polymer (M2), has a melt flow rate MFR (230 °C, 2.16 kg) measured according to ISO 1133 in the range of 15 to 60 g/10 min.

It is especially preferred that the inorganic filler (F) is talc.

The present invention is also directed to an article, comprising the polypropylene composition (C) as described above.

It is preferred that the article is an injection moulded article, more preferably an injection moulded automotive article.

In the following, the present invention is described in more detail.

The polypropylene composition (C)

The inventive polypropylene composition (C) comprises a first heterophasic propylene copolymer (HECO1) comprising a first matrix being a propylene polymer (Ml) and a first elastomeric propylene copolymer (El) and a second heterophasic propylene copolymer (HECO2) comprising a second matrix being a propylene polymer (M2) and a second elastomeric propylene copolymer (E2). The inventive polypropylene composition (C) further comprises an ultra high molecular weight polyethylene (UHMWPE).

Accordingly, the inventive polypropylene composition (C) comprises a heterophasic system comprising matrix (M) formed by the first propylene polymer (Ml) and the second propylene polymer (M2) and the first elastomeric propylene copolymer (El) and the second elastomeric propylene copolymer (E2) are dispersed in said matrix (M). Thus the matrix (M) contains (finely) dispersed inclusions being not part of the matrix (M) and said inclusions contain the first elastomeric propylene copolymer (El) and the second elastomeric propylene copolymer (E2). The term inclusion indicates that the matrix (M) and the inclusion form different phases as defined below.

Further, the inventive polypropylene composition comprises an inorganic filler (F).

Preferably, the polypropylene composition (C) is obtained by a sequential polymerization process wherein at least two, like three, reactors are connected in series. For example, said process comprises the steps of

a) polymerizing propylene and optionally ethylene in a first reactor (Rl) to obtain the first propylene polymer (Ml),

b) transferring the first propylene polymer (Ml) into a second reactor (R2),

c) polymerizing in said second reactor (R2) in the presence of said first propylene polymer (Ml) propylene and optionally ethylene obtaining the second propylene polymer (M2), said first propylene polymer (Ml) and said second propylene polymer (M2) form the matrix (M),

d) transferring the matrix (M) into a third reactor (R3),

e) polymerizing in said third reactor (R3) in the presence of the matrix (M) propylene and/or a C4 to C’x α-olefm, obtaining a third polymer fraction, said polymer fraction is the first elastomeric copolymer (El),

f) transferring the matrix (M) and the first elastomeric copolymer (El) into a fourth reactor (R4),

g) polymerizing in said fourth reactor (R4) in the presence of the matrix (M) and the first elastomeric propylene copolymer (El) propylene and/or a C4 to C’x a-olefm, obtaining a fourth polymer fraction, said polymer fraction is the second elastomeric copolymer (E2), said matrix (M) and said first elastomeric propylene copolymer (El) and said second elastomeric propylene copolymer form a heterophasic propylene copolymer,

h) melt blending said heterophasic propylene copolymer obtained in the fourth reactor (R4) with the inorganic filler (F) and the ultra high molecular weight polyethylene (UHMWPE).

Altematively, the polypropylene composition (C) is obtained by melt blending the first heterophasic propylene copolymer (HECO1) comprising a matrix being the first propylene polymer (Ml) and a dispersed phase being the first elastomeric propylene copolymer (El), the second heterophasic propylene copolymer (HECO2) comprising a matrix being the second propylene polymer (M2) and a dispersed phase being the second elastomeric propylene copolymer (E2), the inorganic filler (F) and the ultra high molecular weight polyethylene (UHMWPE). Melt blending of said first heterophasic propylene copolymer (HECO1) and said second heterophasic propylene copolymer (HECO2) results in a heterophasic system wherein the first propylene polymer (Ml) and the second propylene polymer (M2) form the matrix and the first elastomeric propylene copolymer (El) and the second elastomeric propylene copolymer (E2) form the dispersed phase.

It is especially preferred that the polypropylene composition (C) is obtained by melt blending said first heterophasic propylene copolymer (HECO1) and said second heterophasic propylene copolymer (HECO2) with the inorganic filler (F) and the ultra high molecular weight polyethylene (UHMWPE).

Accordingly, it is preferred that the inventive polypropylene composition (C) comprises 40.0 to 60.0 wt.-%, more preferably 45.0 to 57.0 wt.-%, still more preferably 49.0 to 53.0 wt.-% of the first heterophasic copolymer (HECO1), 10.0 to 25.0 wt.-%, more preferably 12.0 to 20.0 wt.-%, still more preferably 14.0 to 16.0 wt.-% of the second heterophasic copolymer (HECO2), 5.0 to 17.0 wt.-%, more preferably 7.0 to 15.0 wt.-%, still more preferably 9.0 to 11.0 wt.-% of the ultra high molecular weight polyethylene (UHMWPE) and 7.0 to 20.0 wt.-%, more preferably 10.0 to 16.0 wt.-%, still more preferably 12.0 to 14.0 wt.-% of the inorganic filler (F), based on the overall weight of the polypropylene composition (C).

The polypropylene composition (C) of the present invention may include additives (AD).

Accordingly, it is preferred that the inventive polypropylene composition (C) comprises, more preferably consists of, 40.0 to 60.0 wt.-%, more preferably 45.0 to 57.0 wt.-%, still more preferably 49.0 to 53.0 wt.-% of the first heterophasic copolymer (HECO1), 10.0 to 25.0 wt.-%, more preferably 12.0 to 20.0 wt.-%, still more preferably 14.0 to 16.0 wt.-% of

-7the second heterophasic copolymer (HECO2), 5.0 to 17.0 wt.-%, more preferably 7.0 to 15.0 wt.-%, still more preferably 9.0 to 11.0 wt.-% of the ultra high molecular weight polyethylene (UHMWPE) and 7.0 to 20.0 wt.-%, more preferably 10.0 to 16.0 wt.-%, still more preferably 12.0 to 14.0 wt.-% of the inorganic filler (F) and 0.05 to 10.0 wt.-%, preferably 0.1 to 8.0 wt.-% of additives (AD), based on the overall weight of the polypropylene composition (C). The additives (AD) are described in more detail below.

Preferably the polypropylene composition (C) of the invention does not comprise (a) further polymer(s) different to the first propylene polymer (Ml), the second propylene polymer (M2), the first elastomeric propylene copolymer (El), the second elastomeric propylene copolymer (E2) and the ultra high molecular weight polyethylene (UHMWPE) in an amount exceeding 5.0 wt.-%, preferably in an amount exceeding 3.0 wt.-%, more preferably in an amount exceeding 2.5 wt.-%, based on the overall weight of the polypropylene composition (C).

It is preferred that the polypropylene composition (C) has a rather low melt flow rate. Thus, it is preferred that the melt flow rate MFR2 (230 °C) determined according to ISO 1133 of the polypropylene composition (C) is in the range of 3.0 to 25.0 g/10 min, more preferably in the range of 5.0 to 15.0 g/10 min, still more preferably in the range of 7.0 to 13.0 g/10 min.

Further, it is preferred that the polypropylene composition (C) is featured by a rather high tensile modulus. Accordingly, it is preferred that the polypropylene composition (C) has a tensile modulus in the range of 1000 to 2000 MPa, more preferably in the range of 1200 to 1800 MPa, still more preferably in the range of 1400 to 1700 MPa.

In the following, the first heterophasic propylene copolymer (HECO1), the second heterophasic propylene copolymer (HECO2), the ultra high molecular weight polyethylene (UHMWPE) and the inorganic filler (F) are described in more detail.

The first heterophasic propylene copolymer (HECO1)

The inventive polypropylene composition (C) comprises a first heterophasic propylene copolymer (HECO1).

The first heterophasic propylene copolymer (HECO1) according to this invention comprises a matrix (M) being the first propylene polymer (Ml) and dispersed therein a first elastomeric propylene copolymer (El). Thus the matrix (M) contains (finely) dispersed inclusions being not part of the matrix (M) and said inclusions contain the elastomeric propylene copolymer (El). The term inclusion indicates that the matrix (M) and the inclusion form different phases within the first heterophasic propylene copolymer (HECO1). The presence of second phases or the so called inclusions are for instance visible by high resolution microscopy, like electron microscopy or atomic force microscopy, or by dynamic mechanical thermal analysis (DMTA). Specifically, in DMTA the presence of a multiphase structure can be identified by the presence of at least two distinct glass transition temperatures.

Accordingly, first the heterophasic composition (HECO1) according to this invention preferably comprises (a) the (semi)crystalline first propylene polymer (Ml) as the matrix (M) and (b) the first elastomeric propylene copolymer (El).

Preferably the weight ratio between the first propylene polymer (Ml) and the first elastomeric propylene copolymer (El) [PP1/E1] of the heterophasic composition (HECO1) is in the range of 90/10 to 40/60, more preferably in the range of 85/15 to 45/55, yet more preferably in the range of 83/17 to 50/50, like in the range of 82/18 to 60/40.

Preferably, the first heterophasic propylene copolymer (HECO1) according to this invention comprises as polymer components only the first propylene polymer (Ml) and the first elastomeric propylene copolymer (El). In other words, the first heterophasic propylene copolymer (HECO1) may contain further additives but no other polymer in an amount exceeding 5.0 wt.-%, more preferably exceeding 3.0 wt.-%, like exceeding 1.0 wt.-%, based on the total first heterophasic propylene copolymer (HECO1). One additional polymer which

-9may be present in such low amounts is a polyethylene which is a by-reaction product obtained by the preparation of the first heterophasic propylene copolymer (HECO1). Accordingly, it is in particular appreciated that the first heterophasic propylene copolymer (HECO1) contains only the first propylene polymer (Ml), the first elastomeric propylene copolymer (El) and optionally polyethylene in amounts as mentioned in this paragraph.

The first heterophasic propylene copolymer (HECO1) applied according to this invention is featured by a moderate melt flow rate. Accordingly, the first heterophasic propylene copolymer (HECO1) has a melt flow rate MFR2 (230 °C) in the range of 10.0 to 30.0 g/10 min, preferably in the range of 12.0 to 25.0 g/l0 min, more preferably in the range of 16.0 to 20.0 g/10 min.

Preferably, it is desired that the first heterophasic propylene copolymer (HECO1) is thermo mechanically stable. Accordingly, it is appreciated that the first heterophasic propylene copolymer (HECO1) has a melting temperature of at least 160 °C, more preferably in the range of 162 to 170 °C, still more preferably in the range of 163 to 167 °C.

The first heterophasic propylene copolymer (HECO1) comprises apart from propylene also comonomers. Preferably the first heterophasic propylene copolymer (HECO1) comprises apart from propylene ethylene and/or C4 to C’x a-olefins. Accordingly, the term “propylene copolymer” according to this invention is understood as a polypropylene comprising, preferably consisting of, units derivable from (a) propylene and (b) ethylene and/or C4 to C’x a-olefins.

Thus, the first heterophasic propylene copolymer (HECO1), i.e. first propylene polymer (Ml) as well as the first elastomeric propylene copolymer (El), can comprise monomers copolymerizable with propylene, for example comonomers such as ethylene and/or C4 to C’x a-olefins, in particular ethylene and/or C4 to C’x α-olefms, e.g. 1-butene and/or 1-hexene. Preferably, the first heterophasic propylene copolymer (HECO1) according to this invention comprises, especially consists of, monomers copolymerizable with propylene from the group

- 10consisting of ethylene, 1-butene and 1-hexene. More specifically, the first heterophasic propylene copolymer (HECO1) of this invention comprises - apart from propylene - units derivable from ethylene and/or 1-butene. In a preferred embodiment, the first heterophasic propylene copolymer (HECO1) according to this invention comprises units derivable from ethylene and propylene only. Still more preferably the first propylene polymer (Ml) as well as the first elastomeric propylene copolymer (El) of the first heterophasic propylene copolymer (HECO1) contain the same comonomers, like ethylene.

Additionally, it is appreciated that the heterophasic propylene copolymer (HECO1) preferably has moderate total comonomer content, preferably ethylene content. Thus, it is preferred that the comonomer content of the heterophasic propylene copolymer (HECO1) is in the range from 5.0 to 35.0 mol-%, preferably in the range from 8.0 to 20.0 mol-%, more preferably in the range from 9.0 to 15.0 mol-%, like in the range of 10.0 to 12.0 mol-%.

The xylene cold soluble (XCS) fraction measured according to according ISO 16152 (25 °C) of the first heterophasic propylene copolymer (HECO1) is at least 25 wt.-%, preferably in the range from 25.0 to 35.0 wt.-%, more preferably in the range from 26.0 to 32.0 wt.-%, still more preferably in the range from 27.0 to 31.0 wt.-%, based on the overall weight of the first heterophasic propylene copolymer (HECO1).

Further it is appreciated that the xylene cold soluble (XCS) fraction of the first heterophasic propylene copolymer (HECO1) is specified by its intrinsic viscosity. A low intrinsic viscosity (IV) value reflects a low weight average molecular weight. For the present invention it is appreciated that the xylene cold soluble fraction (XCS) of the first heterophasic propylene copolymer (HECO1) has an intrinsic viscosity (IV) measured according to ISO 1628/1 (at 135 °C in decalin) in the range of 1.0 to 4.5 dl/g, preferably in the range of 1.5 to 4.0 dl/g, more preferably in the range of 1.8 to 3.8 dl/g.

Additionally, it is preferred that the comonomer content, i.e. ethylene content, of the xylene cold soluble (XCS) fraction of the first heterophasic propylene copolymer (HECO1) is equal or above 30 mol-%, preferably in the range of 32 to 65 mol-%, more preferably in the range of 35 to 60 mol.-%, yet more preferably in the range of 38 to 55 mol-%. The comonomers

- 11 present in the xylene cold soluble (XCS) fraction are those defined above for the first propylene polymer (Ml) and the first elastomeric propylene copolymer (El), respectively. In one preferred embodiment the comonomer is ethylene only.

The first heterophasic propylene copolymer (HECO1) can be further defined by its individual components, i.e. the first propylene polymer (Ml) and the first elastomeric propylene copolymer (El).

The first propylene polymer (Ml) can be a propylene copolymer or a propylene homopolymer, the latter being preferred.

In case the first propylene polymer (Ml) is a propylene copolymer, the first propylene polymer (Ml) comprises monomers copolymerizable with propylene, for example comonomers such as ethylene and/or C4 to C’x α-olefms, in particular ethylene and/or C4 to Ce α-olefms, e.g. 1-butene and/or 1-hexene. Preferably the first propylene polymer (Ml) according to this invention comprises, especially consists of, monomers copolymerizable with propylene from the group consisting of ethylene, 1-butene and 1-hexene. More specifically the first propylene polymer (Ml) of this invention comprises - apart from propylene - units derivable from ethylene and/or 1-butene. In a preferred embodiment the first propylene polymer (Ml) comprises units derivable from ethylene and propylene only.

The first propylene polymer (Ml) according to this invention has a melt flow rate MFR2 (230 °C/2.16 kg) measured according to ISO 1133 above 50.0 g/10 min, more preferably in the range of 70.0 to 90.0 g/10 min, more preferably in the range of 75.0 to 88.0 g/10 min, still more preferably in the range of 80.0 to 88.0 g/10 min.

The comonomer content of the first propylene polymer (Ml) is in the range of 0.0 to 5.0 mol-%, yet more preferably in the range of 0.0 to 3.0 mol-%, still more preferably in the range of 0.0 to 1.0 mol-%. It is especially preferred that the first propylene polymer (Ml) is a propylene homopolymer (H-PP1).

- 12The first heterophasic propylene copolymer (HECO1) preferably comprises 50 to 90 wt.-%, more preferably 60 to 80 wt.-%, still more preferably 63 to 70 wt.-% of the first propylene polymer (Ml), based on the total weight of the first heterophasic propylene copolymer (HECO1).

Additionally, the first heterophasic propylene copolymer (HECO1) preferably comprises 10 to 50 wt.-%, more preferably 20 to 40 wt.-%, still more preferably 30 to 37 wt.-% of the first elastomeric propylene copolymer (El), based on the total weight of the first heterophasic propylene copolymer (HECO1).

Thus, it is appreciated that the first heterophasic propylene copolymer (HECO1) preferably comprises, more preferably consists of, 50 to 90 wt.-%, more preferably 60 to 80 wt.-%, still more preferably 63 to 70 wt.-% of the first propylene polymer (Ml), like the propylene homopolymer (H-PP1), and 10 to 50 wt.-%, more preferably 20 to 40 wt.-%, still more preferably 30 to 37 wt.-% of the first elastomeric propylene copolymer (El), based on the total weight of the first heterophasic propylene copolymer (HECO1).

Accordingly, a further component of the first heterophasic propylene copolymer (HECO1) is the first elastomeric propylene copolymer (El) dispersed in the matrix (M) being the first propylene polymer (Ml). Concerning the comonomers used in the first elastomeric propylene copolymer (El) it is referred to the information provided for the first heterophasic propylene copolymer (HECO1). Accordingly, the first elastomeric propylene copolymer (El) comprises monomers copolymerizable with propylene, for example comonomers such as ethylene and/or C4 to C’x α-olefms, in particular ethylene and/or C4 to C6 α-olefms, e.g. 1butene and/or 1-hexene. Preferably, the first elastomeric propylene copolymer (El) comprises, especially consists of, monomers copolymerizable with propylene from the group consisting of ethylene, 1-butene and 1-hexene. More specifically, the first elastomeric propylene copolymer (El) comprises - apart from propylene - units derivable from ethylene and/or 1-butene. Thus, in an especially preferred embodiment the first elastomeric propylene copolymer (El) comprises units derivable from ethylene and propylene only.

- 13 The comonomer content of the first elastomeric propylene copolymer (El) preferably is in the range of 60.0 to 85.0 mol-%, more preferably in the range of 70.0 to 80.0 mol-%, still more preferably in the range of 72.0 to 76.0 mol-%.

The first heterophasic propylene copolymer (HECO1) as defined in the instant invention may contain up to 5.0 wt.-% additives, like nucleating agents and antioxidants, as well as slip agents and antiblocking agents. Preferably the additive content (without α-nucleating agents) is below 3.0 wt.-%, like below 1.0 wt.-%.

The first heterophasic propylene copolymer (HECO1) can be produced by blending the first propylene polymer (Ml) and the first elastomeric propylene copolymer (El). However, it is preferred that the first heterophasic propylene copolymer (HECO1) is produced in a sequential step process, using reactors in serial configuration and operating at different reaction conditions. As a consequence, each fraction prepared in a specific reactor may have its own molecular weight distribution and/or comonomer content distribution.

The first heterophasic propylene copolymer (HECO1) according to this invention is preferably produced in a sequential polymerization process, i.e. in a multistage process, known in the art, wherein the first propylene polymer (Ml) is produced at least in one slurry reactor, preferably in a slurry reactor and optionally in a subsequent gas phase reactor, and subsequently the first elastomeric propylene copolymer (El) is produced at least in one, i.e. one or two, gas phase reactor(s).

Accordingly it is preferred that the first heterophasic propylene copolymer (HECO1) is produced in a sequential polymerization process comprising the steps of (a) polymerizing propylene and optionally at least one ethylene and/or C4 to C12 a-olefm in a first reactor (RI) obtaining first propylene polymer (Ml), preferably said first propylene polymer (Ml) is a propylene homopolymer, (b) transferring the first propylene polymer (Ml) into a second reactor (R2), (c) polymerizing in the second reactor (R2) and in the presence of said first propylene polymer (Ml) propylene and at least one ethylene and/or C4 to C12 α-olefin obtaining thereby the first propylene copolymer fraction (ECI), (d) transferring the first propylene polymer (Ml) and the first propylene copolymer fraction (ECI) of step (c) into a third reactor (R3), (e) polymerizing in the third reactor (R3) and in the presence of the first propylene polymer (Ml) and the first propylene copolymer fraction (ECI) obtained in step (c) propylene and ethylene to obtain the second propylene copolymer fraction (EC2), the first propylene polymer (Ml), the first propylene copolymer fraction (ECI) and the second propylene copolymer fraction (EC2) form the first heterophasic propylene copolymer (HECO1).

Of course, in the first reactor (Rl) the second polypropylene fraction can be produced and in the second reactor (R2) the first polypropylene fraction can be obtained. The same holds true for the elastomeric propylene copolymer phase.

Preferably between the second reactor (R2) and the third reactor (R3) the monomers are flashed out.

The term “sequential polymerization process” indicates that the first heterophasic propylene copolymer (HECO1) is produced in at least two, like three or four reactors connected in series. Accordingly, the present process comprises at least a first reactor (Rl) and a second reactor (R2), more preferably a first reactor (Rl), a second reactor (R2), and a third reactor (R3). The term “polymerization reactor” shall indicate that the main polymerization takes place. Thus in case the process consists of four polymerization reactors, this definition does not exclude the option that the overall process comprises for instance a pre-polymerization step in a pre-polymerization reactor. The term “consist of’ is only a closing formulation in view of the main polymerization reactors.

The first reactor (Rl) is preferably a slurry reactor (SR) and can be any continuous or simple stirred batch tank reactor or loop reactor operating in bulk or slurry. Bulk means a polymerization in a reaction medium that comprises of at least 60 % (w/w) monomer. According to the present invention the slurry reactor (SR) is preferably a (bulk) loop reactor (LR).

- 15 The second reactor (R2) can be a slurry reactor, like a loop reactor, as the first reactor or alternatively a gas phase reactor (GPR).

The third reactor (R3) is preferably a gas phase reactor (GPR).

Such gas phase reactors (GPR) can be any mechanically mixed or fluid bed reactors. Preferably the gas phase reactors (GPR) comprise a mechanically agitated fluid bed reactor with gas velocities of at least 0.2 m/sec. Thus it is appreciated that the gas phase reactor is a fluidized bed type reactor preferably with a mechanical stirrer.

Thus in a preferred embodiment the first reactor (Rl) is a slurry reactor (SR), like a loop reactor (LR), whereas the second reactor (R2) and the third reactor (R3) are gas phase reactors (GPR). Accordingly for the instant process at least three, preferably three polymerization reactors, namely a slurry reactor (SR), like a loop reactor (LR), a first gas phase reactor (GPR-1) and a second gas phase reactor (GPR-2) connected in series are used. If needed prior to the slurry reactor (SR) a pre-polymerization reactor is placed.

In another preferred embodiment the first reactor (Rl) and second reactor (R2) are slurry reactors (SR), like a loop reactors (LR), whereas the third reactor (R3) is a gas phase reactors (GPR). Accordingly for the instant process at least three, preferably three polymerization reactors, namely two slurry reactors (SR), like two loop reactors (LR), and a gas phase reactor (GPR-1) connected in series are used. If needed prior to the first slurry reactor (SR) a pre-polymerization reactor is placed.

A preferred multistage process is a “loop-gas phase”-process, such as developed by Borealis A/S, Denmark (known as BORSTAR® technology) described e.g. in patent literature, such as in EP 0 887 379, WO 92/12182 WO 2004/000899, WO 2004/111095, WO 99/24478, WO 99/24479 or in WO 00/68315.

A further suitable slurry-gas phase process is the Spheripol® process of Basell.

- 16Preferably, in the instant process for producing the first heterophasic propylene copolymer (HECO1) as defined above the conditions for the first reactor (Rl), i.e. the slurry reactor (SR), like a loop reactor (LR), of step (a) may be as follows:

the temperature is within the range of 50 °C to 110 °C, preferably between 60 °C and 100 °C, more preferably between 68 and 95 °C, the pressure is within the range of 20 bar to 80 bar, preferably between 40 bar to bar, hydrogen can be added for controlling the molar mass in a manner known per se.

Subsequently, the reaction mixture from step (a) is transferred to the second reactor (R2), i.e. gas phase reactor (GPR-1), i.e. to step (c), whereby the conditions in step (c) are preferably as follows:

the temperature is within the range of 50 °C to 130 °C, preferably between 60 °C and 100 °C, the pressure is within the range of 5 bar to 50 bar, preferably between 15 bar to bar, hydrogen can be added for controlling the molar mass in a manner known per se.

The condition in the third reactor (R3), preferably in the second gas phase reactor (GPR-2) is similar to the second reactor (R2).

The residence time can vary in the three reactor zones.

In one embodiment of the process for producing the polypropylene the residence time in bulk reactor, e.g. loop is in the range 0.1 to 2.5 hours, e.g. 0.15 to 1.5 hours and the residence time in gas phase reactor will generally be 0.2 to 6.0 hours, like 0.5 to 4.0 hours.

If desired, the polymerization may be effected in a known manner under supercritical conditions in the first reactor (Rl), i.e. in the slurry reactor (SR), like in the loop reactor (LR), and/or as a condensed mode in the gas phase reactors (GPR).

- 17Preferably the process comprises also a prepolymerization with the catalyst system, as described in detail below, comprising a Ziegler-Natta procatalyst, an external donor and optionally a cocatalyst.

In a preferred embodiment, the prepolymerization is conducted as bulk slurry polymerization in liquid propylene, i.e. the liquid phase mainly comprises propylene, with minor amount of other reactants and optionally inert components dissolved therein.

The prepolymerization reaction is typically conducted at a temperature of 10 to 60 °C, preferably from 15 to 50 °C, and more preferably from 20 to 45 °C.

The pressure in the prepolymerization reactor is not critical but must be sufficiently high to maintain the reaction mixture in liquid phase. Thus, the pressure may be from 20 to 100 bar, for example 30 to 70 bar.

The catalyst components are preferably all introduced to the prepolymerization step. However, where the solid catalyst component (i) and the cocatalyst (ii) can be fed separately it is possible that only a part of the cocatalyst is introduced into the prepolymerization stage and the remaining part into subsequent polymerization stages. Also in such cases it is necessary to introduce so much cocatalyst into the prepolymerization stage that a sufficient polymerization reaction is obtained therein.

It is possible to add other components also to the prepolymerization stage. Thus, hydrogen may be added into the prepolymerization stage to control the molecular weight of the prepolymer as is known in the art. Further, antistatic additive may be used to prevent the particles from adhering to each other or to the walls of the reactor.

The precise control of the prepolymerization conditions and reaction parameters is within the skill of the art.

According to the invention the heterophasic propylene copolymer (HECO) is obtained by a multistage polymerization process, as described above, in the presence of a catalyst system

- 18 comprising as component (i) a Ziegler-Natta procatalyst which contains a trans-esterification product of a lower alcohol and a phthalic ester.

The first heterophasic propylene copolymer (HECO1) according to this invention is preferably produced in the presence of (a) a Ziegler-Natta catalyst (ZN-C1) comprising compounds (TC) of a transition metal of Group 4 to 6 of IUPAC, a Group 2 metal compound (MC) and an internal donor (ID);

(b) optionally a co-catalyst (Co), and (c) optionally an external donor (ED).

This Ziegler-Natta catalyst (ZN-C1) can be any stereospecific Ziegler-Natta catalyst for propylene polymerization, which preferably is capable of catalysing the polymerization and copolymerization of propylene and optional comonomers at a pressure of 500 to 10000 kPa, in particular 2500 to 8000 kPa, and at a temperature of 40 to 110°C, in particular of 60 to 110°C.

Preferably, the Ziegler-Natta catalyst (ZN-C1) comprises a high-yield Ziegler-Natta type catalyst including an internal donor component, which can be used at high polymerization temperatures of 80°C or more. Such high-yield Ziegler-Natta catalyst (ZN-C1) can comprise a succinate, a diether, a phthalate etc., or mixtures therefrom as internal donor (ID) and are for example commercially available from LyondellBasell. An example for a suitable catalyst is the catalyst ZN 104 of LyondellBasell.

Additional suitable catalysts are described for example in EP 2738214 Al and WO 2016/066453 Al.

The Ziegler-Natta catalyst (ZN-C1) is preferably used in association with an alkyl aluminum cocatalyst and optionally external donors.

As further component in the instant polymerization process an external donor (ED) is preferably present. Suitable external donors (ED) include certain silanes, ethers, esters,

- 19amines, ketones, heterocyclic compounds and blends of these. It is especially preferred to use a silane. It is most preferred to use silanes of the general formula

R^apR^bqSi(OR^c)(₄-p-_q) wherein R^a, R^b and R^c denote a hydrocarbon radical, in particular an alkyl or cycloalkyl group, and wherein p and q are numbers ranging from 0 to 3 with their sum p + q being equal to orless than 3. R^a, R^b and R^c can be chosen independently from one another and can be the same or different. Specific examples of such silanes are (tert-butyl)2Si(OCH3)2, (cyclohexyl)(methyl)Si(OCH3)2, (phenylρΞΚΟΟΉγ and (cyclopentyl)2Si(OCH3)2, or of general formula

Si(OCH₂CH₃)3(NR³R⁴) wherein R3 and R4 can be the same or different a represent a hydrocarbon group having 1 to 12 carbon atoms.

R3 and R4 are independently selected from the group consisting of linear aliphatic hydrocarbon group having 1 to 12 carbon atoms, branched aliphatic hydrocarbon group having 1 to 12 carbon atoms and cyclic aliphatic hydrocarbon group having 1 to 12 carbon atoms. It is in particular preferred that R3 and R4 are independently selected from the group consisting of methyl, ethyl, n-propyl, n-butyl, octyl, decanyl, iso-propyl, iso-butyl, isopentyl, tert.-butyl, tert.-amyl, neopentyl, cyclopentyl, cyclohexyl, methylcyclopentyl and cycloheptyl.

More preferably both R³ and R⁴ are the same, yet more preferably both R³ and R⁴ are an ethyl group.

Especially preferred external donors (ED) are the dicyclopentyl dimethoxy silane donor (D donor) or the cyclohexylmethyl dimethoxy silane donor (C-Donor).

In addition to the Ziegler-Natta catalyst (ZN-C1) and the optional external donor (ED) a cocatalyst can be used. The co-catalyst is preferably a compound of group 13 of the periodic table (IUPAC), e.g. organo aluminum, such as an aluminum compound, like aluminum alkyl, aluminum halide or aluminum alkyl halide compound. Accordingly, in one specific embodiment the co-catalyst (Co) is a trialkylaluminium, like triethylaluminium (TEAL),

-20dialkyl aluminium chloride or alkyl aluminium dichloride or mixtures thereof. In one specific embodiment the co-catalyst (Co) is triethylaluminium (TEAL).

Preferably the ratio between the co-catalyst (Co) and the external donor (ED) [Co/ED] and/or mthe ratio between the co-catalyst (Co) and the transition metal (TM) [Co/TM] should be carefully chosen.

Accordingly, (a) the mol-ratio of co-catalyst (Co) to external donor (ED) [Co/ED] must be in the range of 5 to 45, preferably is in the range of 5 to 35, more preferably is in the range of 5 to 25;

and optionally (b) the mol-ratio of co-catalyst (Co) to titanium compound (TC) [Co/TC] must be in the range of above 80 to 500, preferably is in the range of 100 to 350, still more preferably is in the range of 120 to 300.

The second heterophasic propylene copolymer (HECO2)

The inventive polypropylene composition (C) further comprises a second heterophasic propylene copolymer (HECO2).

The second heterophasic propylene copolymer (HECO2) according to this invention comprises a matrix (M) being the second propylene polymer (M2) and dispersed therein an elastomeric propylene copolymer (E) being the second elastomeric propylene copolymer (E2). Thus the matrix (M) contains (finely) dispersed inclusions being not part of the matrix (M) and said inclusions contain the elastomeric propylene copolymer (E). With regard to the term “inclusion”, reference is made to the definition provided above regarding the first heterophasic propylene copolymer (HECO1).

Accordingly, the second heterophasic composition (HECO2) according to this invention preferably comprises (a) the (semi)crystalline second propylene polymer (M2) as the matrix (M) and

-21 (b) the second elastomeric propylene copolymer (E2).

Preferably the weight ratio between the second propylene polymer (M2) and the elastomeric propylene copolymer (E2) [M2/E2] of the second heterophasic composition (HECO2) is in the range of 90/10 to 40/60, more preferably in the range of 85/15 to 45/55, yet more preferably in the range of 83/17 to 50/50, like in the range of 82/18 to 60/40.

Preferably, the second heterophasic propylene copolymer (HECO2) according to this invention comprises as polymer components only the second propylene polymer (M2) and the second elastomeric propylene copolymer (E2). In other words, the second heterophasic propylene copolymer (HECO2) may contain further additives but no other polymer in an amount exceeding 5.0 wt.-%, more preferably exceeding 3.0 wt.-%, like exceeding 1.0 wt.-%, based on the total second heterophasic propylene copolymer (HECO2). One additional polymer which may be present in such low amounts is a polyethylene which is a reaction by-product obtained by the preparation of the second heterophasic propylene copolymer (HECO2). Accordingly, it is in particular appreciated that the instant second heterophasic propylene copolymer (HECO2) contains only the second propylene polymer (M2), the second elastomeric propylene copolymer (E2) and optionally polyethylene in amounts as mentioned in this paragraph.

The second heterophasic propylene copolymer (HECO2) applied according to this invention is featured by a moderate melt flow rate. Accordingly, the second heterophasic propylene copolymer (HECO2) has a melt flow rate MFR2 (230 °C) in the range of 10 to 30 g/10 min, preferably in the range of 15 to 25 g/10 min, more preferably in the range of 18 to 21 g/10 min.

Preferably, it is desired that the second heterophasic propylene copolymer (HECO2) is thermo mechanically stable. Accordingly, it is appreciated that the second heterophasic propylene copolymer (HECO2) has a melting temperature of at least 160 °C, more preferably in the range of 160 to 167 °C, still more preferably in the range of 162 to 165 °C.

-22The second heterophasic propylene copolymer (HECO2) comprises apart from propylene also comonomers. Preferably the second heterophasic propylene copolymer (HECO2) comprises apart from propylene ethylene and/or C4 to C’x α-olefins. Accordingly, the term “propylene copolymer” according to this invention is understood as a polypropylene comprising, preferably consisting of, units derivable from (a) propylene and (b) ethylene and/or C4 to C’x a-olefins.

Thus, the second heterophasic propylene copolymer (HECO2), i.e. second propylene polymer (M2) as well as the second elastomeric propylene copolymer (E2), can comprise monomers copolymerizable with propylene, for example comonomers such as ethylene and/or C4 to C’x α-olefins, in particular ethylene and/or C4 to C’x α-olefins, e.g. 1-butene and/or 1-hexene. Preferably, the second heterophasic propylene copolymer (HECO2) according to this invention comprises, especially consists of, monomers copolymerizable with propylene from the group consisting of ethylene, 1-butene and 1-hexene. More specifically, the second heterophasic propylene copolymer (HECO2) of this invention comprises - apart from propylene - units derivable from ethylene and/or 1-butene. In a preferred embodiment, the second heterophasic propylene copolymer (HECO2) according to this invention comprises units derivable from ethylene and propylene only. Still more preferably the second propylene polymer (M2) as well as the second elastomeric propylene copolymer (E2) of the second heterophasic propylene copolymer (HECO2) contain the same comonomers, like ethylene.

Further, it is preferred that the second heterophasic propylene copolymer (HECO2) and the first heterophasic propylene copolymer (HECO1) contain the same comonomer, like ethylene.

Additionally, it is appreciated that the second heterophasic propylene copolymer (HECO2) preferably has a rather low total comonomer content, preferably ethylene content. Thus, it is preferred that the comonomer content of the second heterophasic propylene copolymer

-23 (HECO2) is in the range from 4.0 to 17.0 mol-%, preferably in the range from 6.0 to 14.0 mol-%, more preferably in the range from 10.0 to 11.0 mol-%.

The xylene cold soluble (XCS) fraction measured according to according ISO 16152 (25 °C) of the second heterophasic propylene copolymer (HECO2) is below 25.0 wt.-%, more preferably in the range of 10.0 to 24.0 wt.-%, preferably in the range from 12.0 to 22.0 wt.-%, more preferably in the range from 15.0 to 20.0 wt.-%, still more preferably in the range from 17.0 to 19.0 wt.-%.

Further it is appreciated that the xylene cold soluble (XCS) fraction of the second heterophasic propylene copolymer (HECO2) is specified by its intrinsic viscosity. A low intrinsic viscosity (IV) value reflects a low weight average molecular weight. For the present invention it is appreciated that the xylene cold soluble fraction (XCS) of the second heterophasic propylene copolymer (HECO2) has an intrinsic viscosity (IV) measured according to ISO 1628/1 (at 135 °C in decalin) in the range of 1.0 to 3.3 dl/g, preferably in the range of 1.5 to 3.0 dl/g, more preferably in the range of 2.0 to 2.7 dl/g.

Additionally, it is preferred that the comonomer content, i.e. ethylene content, of the xylene cold soluble (XCS) fraction of the second heterophasic propylene copolymer (HECO2) is equal or above 35 mol-%, preferably in the range of 35 to 55 mol-%, more preferably in the range of 40 to 50 mol.-%, yet more preferably in the range of 43 to 46 mol.-%. The comonomers present in the xylene cold soluble (XCS) fraction are those defined above for the second propylene polymer (M2) and the second elastomeric propylene copolymer (E2), respectively. In one preferred embodiment the comonomer is ethylene only.

The second heterophasic propylene copolymer (HECO2) can be further defined by its individual components, i.e. the second propylene polymer (M2) and the second elastomeric propylene copolymer (E2).

The second propylene polymer (M2) can be a propylene copolymer or a propylene homopolymer, the latter being preferred.

-24In case the second propylene polymer (M2) is a propylene copolymer, the second propylene polymer (M2) comprises monomers copolymerizable with propylene, for example comonomers such as ethylene and/or C4 to C’x α-olefms, in particular ethylene and/or C4 to Ce α-olefms, e.g. 1-butene and/or 1-hexene. Preferably the second propylene polymer (M2) according to this invention comprises, especially consists of, monomers copolymerizable with propylene from the group consisting of ethylene, 1-butene and 1-hexene. More specifically the second propylene polymer (M2) of this invention comprises - apart from propylene - units derivable from ethylene and/or 1-butene. In a preferred embodiment the second propylene polymer (M2) comprises units derivable from ethylene and propylene only.

The second propylene polymer (M2) according to this invention has a melt flow rate MFR2 (230 °C/2.16 kg) measured according to ISO 1133 in the range of 15 to 60 g/10 min, more preferably in the range of 25 to 50 g/10 min, still more preferably in the range of 35 to 42 g/10 min.

As mentioned above the second heterophasic propylene copolymer (HECO2) is featured by a low comonomer content. Accordingly, the comonomer content of the second propylene polymer (M2) is in the range of 0.0 to 5.0 mol-%, yet more preferably in the range of 0.0 to 3.0 mol-%, still more preferably in the range of 0.0 to 1.0 mol-%. It is especially preferred that the second propylene polymer (M2) is a propylene homopolymer.

The second heterophasic propylene copolymer (HECO2) preferably comprises 60 to wt.-%, more preferably 60 to 90 wt.-%, still more preferably 70 to 85 wt.-% of the second propylene polymer (M2), based on the total weight of the second heterophasic propylene copolymer (HECO2).

Additionally, the second heterophasic propylene copolymer (HECO2) preferably comprises 5 to 40 wt.-%, more preferably 10 to 40 wt.-%, still more preferably 15 to 30 wt.-% of the second elastomeric propylene copolymer (E2), based on the total weight of the second heterophasic propylene copolymer (HECO2).

-25 Thus, it is appreciated that the second heterophasic propylene copolymer (HECO2) preferably comprises, more preferably consists of, 60 to 95 wt.-%, more preferably 60 to 90 wt.-%, still more preferably 70 to 85 wt.-% of the second propylene polymer (M2) and 5 to 40 wt.-%, more preferably 10 to 40 wt.-%, still more preferably 15 to 30 wt.-% of the second elastomeric propylene copolymer (E2), based on the total weight of the second heterophasic propylene copolymer (HECO2).

Accordingly, a further component of the second heterophasic propylene copolymer (HECO2) is the second elastomeric propylene copolymer (E2) dispersed in the matrix (M) being the second propylene polymer (M2). Concerning the comonomers used in the second elastomeric propylene copolymer (E2) it is referred to the information provided for the second heterophasic propylene copolymer (HECO2). Accordingly, the second elastomeric propylene copolymer (E2) comprises monomers copolymerizable with propylene, for example comonomers such as ethylene and/or C4 to C’x α-olefms, in particular ethylene and/or C4 to C6 α-olefms, e.g. 1-butene and/or 1-hexene. Preferably, the second elastomeric propylene copolymer (E2) comprises, especially consists of, monomers copolymerizable with propylene from the group consisting of ethylene, 1-butene and 1-hexene. More specifically, the second elastomeric propylene copolymer (E2) comprises - apart from propylene - units derivable from ethylene and/or 1-butene. Thus, in an especially preferred embodiment the second elastomeric propylene copolymer (E2) comprises units derivable from ethylene and propylene only.

The comonomer content of the second elastomeric propylene copolymer (E2) preferably is in the range of 40.0 to 75.0 mol-%, more preferably in the range of 47.0 to 66.0 mol-%, still more preferably in the range of 55.0 to 62.0 mol-%.

The second heterophasic propylene copolymer (HECO2) as defined in the instant invention may contain up to 5.0 wt.-% additives, like nucleating agents and antioxidants, as well as slip agents and antiblocking agents. Preferably the additive content (without α-nucleating agents) is below 3.0 wt.-%, like below 1.0 wt.-%.

-26According to a preferred embodiment of the present invention, the second heterophasic propylene copolymer (HECO2) contains an α-nucleating agent.

According to this invention the alpha nucleating agent is not an additive (AD). Regarding the preferred alpha nucleating agents for the second heterophasic propylene copolymer (HECO2), reference is made to the nucleating agents for the first heterophasic propylene copolymer (HECO1) provided above.

The second heterophasic propylene copolymer (HECO2) can be produced by blending the second propylene polymer (M2) and the second elastomeric propylene copolymer (E2). However, it is preferred that the second heterophasic propylene copolymer (HECO2) is produced in a sequential step process, using reactors in serial configuration and operating at different reaction conditions. As a consequence, each fraction prepared in a specific reactor may have its own molecular weight distribution and/or comonomer content distribution.

The second heterophasic propylene copolymer (HECO2) according to this invention is preferably produced in a sequential polymerization process, i.e. in a multistage process, known in the art, wherein the second propylene polymer (M2) is produced at least in one slurry reactor, preferably in a slurry reactor and optionally in a subsequent gas phase reactor, and subsequently the second elastomeric propylene copolymer (E2) is produced at least in one, i.e. one or two, gas phase reactor(s).

Accordingly it is preferred that the second heterophasic propylene copolymer (HECO2) is produced in a sequential polymerization process comprising the steps of (a) polymerizing propylene and optionally at least one ethylene and/or C4 to C12 a-olefin in a first reactor (Rl) obtaining the first polypropylene fraction of the second propylene polymer (M2), preferably said first polypropylene fraction is a propylene homopolymer, (b) transferring the first polypropylene fraction into a second reactor (R2), (c) polymerizing in the second reactor (R2) and in the presence of said first polypropylene fraction propylene and optionally at least one ethylene and/or C4 to C12 α-olefm obtaining thereby the second polypropylene fraction, preferably said second polypropylene fraction is a second propylene homopolymer, said first polypropylene fraction and said second polypropylene fraction form the second propylene polymer (M2), i.e. the matrix of the second heterophasic propylene copolymer (HECO2), (d) transferring the second propylene polymer (M2) of step (c) into a third reactor (R3), (e) polymerizing in the third reactor (R3) and in the presence of the second propylene polymer (M2) obtained in step (c) propylene and ethylene to obtain the second elastomeric propylene copolymer (E2) dispersed in the second propylene polymer (M2), the second propylene polymer (M2) and the second elastomeric propylene copolymer (E2) form the second heterophasic propylene copolymer (HECO2).

Regarding the term “sequential polymerization process”, reference is made to the definition provided above with regard to the first heterophasic propylene copolymer (HECO1).

The second reactor (R2) can be a slurry reactor, like a loop reactor, as the first reactor or alternatively a gas phase reactor (GPR).

The third reactor (R3) is preferably a gas phase reactor (GPR).

-28 Such gas phase reactors (GPR) can be any mechanically mixed or fluid bed reactors. Preferably the gas phase reactors (GPR) comprise a mechanically agitated fluid bed reactor with gas velocities of at least 0.2 m/sec. Thus it is appreciated that the gas phase reactor is a fluidized bed type reactor preferably with a mechanical stirrer.

Preferably, in the instant process for producing the second heterophasic propylene copolymer (HECO2) as defined above the conditions for the first reactor (Rl), i.e. the slurry reactor (SR), like a loop reactor (LR), of step (a) may be as follows:

the temperature is within the range of 50 °C to 110 °C, preferably between 60 °C and

100 °C, more preferably between 68 and 95 °C,

-29the pressure is within the range of 20 bar to 80 bar, preferably between 40 bar to bar, hydrogen can be added for controlling the molar mass in a manner known per se.

the temperature is within the range of 50 °C to 130 °C, preferably between 60 °C and

100 °C, the pressure is within the range of 5 bar to 50 bar, preferably between 15 bar to bar, hydrogen can be added for controlling the molar mass in a manner known per se.

The residence time can vary in the three reactor zones.

Preferably the process comprises also a prepolymerization with the catalyst system, as described in detail below, comprising a Ziegler-Natta procatalyst, an external donor and optionally a cocatalyst.

-30In a preferred embodiment, the prepolymerization is conducted as bulk slurry polymerization in liquid propylene, i.e. the liquid phase mainly comprises propylene, with minor amount of other reactants and optionally inert components dissolved therein.

According to the invention the second heterophasic composition (HECO2) is obtained by a multistage polymerization process, as described above, in the presence of a catalyst system comprising as component (i) a Ziegler-Natta procatalyst which contains a trans-esterification product of a lower alcohol and a phthalic ester.

-31 The procatalyst used according to the invention for preparing the second heterophasic composition (HECO2) is prepared by

a) reacting a spray crystallized or emulsion solidified adduct of MgC’F and a C1-C2 alcohol with TiC’U

b) reacting the product of stage a) with a dialkylphthalate of formula (I)

O

wherein R¹ and R² are independently at least a C5 alkyl under conditions where a transesterification between said Ci to C2 alcohol and said dialkylphthalate of formula (I) takes place to form the internal donor

c) washing the product of stage b) or

d) optionally reacting the product of step c) with additional TiC’U.

The procatalyst is produced as defined for example in the patent applications WO 87/07620, WO 92/19653, WO 92/19658 and EP 0 491 566. The content of these documents is herein included by reference.

First an adduct of MgCF and a C1-C2 alcohol of the formula MgC12*nROH, wherein R is methyl or ethyl and n is 1 to 6, is formed. Ethanol is preferably used as alcohol.

The adduct, which is first melted and then spray crystallized or emulsion solidified, is used as catalyst carrier.

In the next step the spray crystallized or emulsion solidified adduct of the formula MgC12*nROH, wherein R is methyl or ethyl, preferably ethyl and n is 1 to 6, is contacting with TiC’U to form a titanized carrier, followed by the steps of • adding to said titanised carrier (i) a dialkylphthalate of formula (I) with R¹ and R² being independently at

-32or preferably (ii) a dialkylphthalate of formula (I) with R¹ and R² being the same and being at least a Cs-alkyl, like at least a Cx-alkyl.

or more preferably (iii) a dialkylphthalate of formula (I) selected from the group consisting of propylhexylphthalate (PrHP), dioctylphthalate (DOP), di-isodecylphthalate (DIDP), and ditridecylphthalate (DTDP), yet more preferably the dialkylphthalate of formula (I) is a dioctylphthalate (DOP), like di-iso-octylphthalate or diethylhexylphthalate, in particular diethylhexylphthalate, to form a first product, subjecting said first product to suitable transesterification conditions, i.e. to a temperature above 100 °C, preferably between 100 to 150 °C, more preferably between 130 to 150 °C, such that said methanol or ethanol is transesterified with said ester groups of said dialkylphthalate of formula (I) to form preferably at least 80 mol-%, more preferably 90 mol-%, most preferably 95 mol.-%, of a dialkylphthalate of formula (II)

O

with R¹ and R² being methyl or ethyl, preferably ethyl, the dialkylphthalat of formula (II) being the internal donor and recovering said transesterification product as the procatalyst composition (component (i)).

The adduct of the formula MgC12*nROH, wherein R is methyl or ethyl and n is 1 to 6, is in a preferred embodiment melted and then the melt is preferably injected by a gas into a cooled solvent or a cooled gas, whereby the adduct is crystallized into a morphologically advantageous form, as for example described in WO 87/07620.

-33 This crystallized adduct is preferably used as the catalyst carrier and reacted to the procatalyst useful in the present invention as described in WO 92/19658 and WO 92/19653.

As the catalyst residue is removed by extracting, an adduct of the titanised carrier and the internal donor is obtained, in which the group deriving from the ester alcohol has changed.

In case sufficient titanium remains on the carrier, it will act as an active element of the procatalyst.

Otherwise the titanization is repeated after the above treatment in order to ensure a sufficient titanium concentration and thus activity.

Preferably the procatalyst used according to the invention contains 2.5 wt.-% of titanium at the most, preferably 2.2% wt.-% at the most and more preferably 2.0 wt.-% at the most. Its donor content is preferably between 4 to 12 wt.-% and more preferably between 6 and 10 wt.-%.

More preferably the procatalyst used according to the invention has been produced by using ethanol as the alcohol and dioctylphthalate (DOP) as dialkylphthalate of formula (I), yielding diethyl phthalate (DEP) as the internal donor compound.

Still more preferably the catalyst used according to the invention is the catalyst as described in the example section; especially with the use of dioctylphthalate as dialkylphthalate of formula (I).

For the production of the second heterophasic composition (HECO2) according to the invention the catalyst system used preferably comprises in addition to the special ZieglerNatta procatalyst an organometallic cocatalyst as component (ii).

Accordingly it is preferred to select the cocatalyst from the group consisting of trialkylaluminium, like triethylaluminium (TEA), dialkyl aluminium chloride and alkyl aluminium sesquichloride.

-34Component (iii) of the catalysts system used is an external donor represented by formula (Illa) or (Illb). Formula (Illa) is defined by

Si(OCH₃)₂R₂ ⁵ (Illa) wherein R⁵ represents a branched-alkyl group having 3 to 12 carbon atoms, preferably a branched-alkyl group having 3 to 6 carbon atoms, or a cyclo-alkyl having 4 to 12 carbon atoms, preferably a cyclo-alkyl having 5 to 8 carbon atoms.

It is in particular preferred that R⁵ is selected from the group consisting of iso-propyl, isobutyl, iso-pentyl, tert.-butyl, tert.-amyl, neopentyl, cyclopentyl, cyclohexyl, methylcyclopentyl and cycloheptyl.

Formula (Illb) is defined by

Si(OCH₂CH₃)₃(NR^xR^y) (Illb) wherein R^x and R^y can be the same or different a represent a hydrocarbon group having 1 to 12 carbon atoms.

R^x and R^y are independently selected from the group consisting of linear aliphatic hydrocarbon group having 1 to 12 carbon atoms, branched aliphatic hydrocarbon group having 1 to 12 carbon atoms and cyclic aliphatic hydrocarbon group having 1 to 12 carbon atoms. It is in particular preferred that R^x and R^y are independently selected from the group consisting of methyl, ethyl, n-propyl, n-butyl, octyl, decanyl, iso-propyl, iso-butyl, isopentyl, tert.-butyl, tert.-amyl, neopentyl, cyclopentyl, cyclohexyl, methylcyclopentyl and cycloheptyl.

More preferably both R^x and R^y are the same, yet more preferably both R^x and R^y are an ethyl group.

More preferably the external donor is of formula (Illa), like dicyclopentyl dimethoxy silane [Si(OCH₃)₂(cyclo-pentyl)₂], diisopropyl dimethoxy silane [Si(OCH₃)₂(CH(CH₃)₂)₂],

-35 Most preferably the external donor is dicyclopentyl dimethoxy silane [Si(OCH3)₂(cyclopentyl)₂].

In a further embodiment, the Ziegler-Natta procatalyst can be modified by polymerising a vinyl compound in the presence of the catalyst system, comprising the special Ziegler-Natta procatalyst (component (i)), an external donor (component (iii) and optionally a cocatalyst (component (iii)), which vinyl compound has the formula:

ch₂=ch-chr³r⁴ wherein R³ and R⁴ together form a 5- or 6-membered saturated, unsaturated or aromatic ring or independently represent an alkyl group comprising 1 to 4 carbon atoms, and the modified catalyst is used for the preparation of the heterophasic composition (HECO) according to this invention. The polymerized vinyl compound can act as an α-nucleating agent.

Concerning the modification of catalyst reference is made to the international applications WO 99/24478, WO 99/24479 and particularly WO 00/68315, incorporated herein by reference with respect to the reaction conditions concerning the modification of the catalyst as well as with respect to the polymerization reaction.

The ultra high molecular weight polyethylene (UHMWPE)

The polypropylene composition (C) further comprises an ultra high molecular weight polyethylene (UHMWPE).

The expression “ultra high molecular weight polyethylene” used in the instant invention relates to a polyethylene having a very high molecular weight. In particular, the nominal viscosity molecular weight Mv of the ultra high molecular weight polyethylene (UHMWPE) according to the instant invention is at least 500 kg/mol, more preferably in the range of 500 to 5000 kg/mol, still more preferably in the range of 1000 to 4000 kg/mol, like in the range of 2000 to 3800 kg/mol.

-36Further, it is preferred that the ultra high molecular weight polyethylene (UHMWPE) is a homopolymer of ethylene, i.e. consists of more than 99.70 mol-%, still more preferably of at least 99.80 mol-%, of ethylene units. In a preferred embodiment only ethylene units in the ultra high molecular weight polyethylene (UHMWPE) are detectable.

It is especially preferred that the ultra high molecular weight polyethylene (UHMWPE) is obtained in the presence of a Ziegler-Natta or metallocene catalyst.

The ultra high molecular weight polyethylene (UHMWPE) preferably has a density of at least 920 g/cm³. More preferably, the ultra high molecular weight polyethylene (UHMWPE) has a density in the range of 922 to 940 g/cm³, still more preferably in the range of 923 to 938 g/cm³, like in the range of 924 to 936 g/cm³.

Further it is preferred that the ultra high molecular weight polyethylene (UHMWPE) has a rather broad molecular weight distribution (Mw/Mn). Accordingly, it is preferred that the molecular weight distribution (Mw/Mn) of the ultra high molecular weight polyethylene (UHMWPE) is in the range of 1.0 to 10.0, more preferably in the range of 2.0 to 8.0, like in the range of 3.0 to 7.0.

Preferably, the melt flow rate MFR21 (190 °C, 21.6 kg) measured according to ISO 1133 of the ultra high molecular weight polyethylene (UHMWPE) is preferably below 2.0 g/10 min, more preferably below 1.0 g/10 min, still more preferably below 0.1 g/10 min.

Preferably, the ultra high molecular weight polyethylene (UHMWPE) according to the present invention is a high density polyethylene known in the art. In particular, it is preferred that the ultra high molecular weight polyethylene (UHMWPE) is one of the commercial ethylene homopolymers M2 or M3 of Jingchem.

-37The inorganic filler (F)

A further requirement of the composition according to this invention is the presence of an inorganic filler (F).

Preferably the inorganic filler (F) is a mineral filler. It is appreciated that the inorganic filler (F) is a phyllosilicate, mica or wollastonite. Even more preferred the inorganic filler (F) is selected from the group consisting of mica, wollastonite, kaolinite, smectite, montmorillonite and talc.

The most preferred inorganic fillers (F) are talc and/or wollastonite. It is especially preferred that the inorganic filler (F) is talc.

It is appreciated that the filler (F) has median particle size (D50) in the range of 0.8 to 20 pm and a top cut particle size (D95) in the range of 10 to 20 pm, preferably a median particle size (D50) in the range of 5.0 to 8.0 pm and top cut particle size (D95) in the range of 12 to 17 pm, more preferably a median particle size (D50) in the range of 5.5 to 7.8 pm and top cut particle size (D95) of 13 to 16.5 pm.

According to this invention the filler (F) does not belong to the class of alpha nucleating agents and additives (AD).

The the filler (F) is state of the art and a commercially available product.

Additives (AD)

In addition the first heterophasic propylene copolymer (HECO1), the second heterophasic propylene copolymer (HECO2), the inorganic filler (F) and the ultra high molecular weight polyethylene (UHMWPE), the composition (C) of the invention may include additives (AD). Typical additives are acid scavengers, antioxidants, colorants, light stabilisers, plasticizers, slip agents, anti-scratch agents, dispersing agents, processing aids, lubricants, pigments, and the like. As indicated above the inorganic filler (F) is not regarded as an additive (AD).

-38Such additives are commercially available and for example described in “Plastic Additives Handbook”, 6^th edition 2009 of Hans Zweifel (pages 1141 to 1190).

Furthermore, the term “additives (AD)” according to the present invention also includes carrier materials, in particular polymeric carrier materials.

The Polymeric Carrier Material

Preferably the composition (C) of the invention does not comprise (a) further polymer (s) different to the first and second heterophasic propylene copolymers (HECO1) and (HECO2), and the ultra high molecular weight polyethylene (UHMWPE) in an amount exceeding 15 wt.-%, preferably in an amount exceeding 10 wt.-%, more preferably in an amount exceeding 9 wt.-%, based on the weight of the composition (C). Any polymer being a carrier material for additives (AD) is not calculated to the amount of polymeric compounds as indicated in the present invention, but to the amount of the respective additive.

The polymeric carrier material of the additives (AD) is a carrier polymer to ensure a uniform distribution in the composition (C) of the invention. The polymeric carrier material is not limited to a particular polymer. The polymeric carrier material may be ethylene homopolymer, ethylene copolymer obtained from ethylene and α-olefm comonomer such as C3 to Cs α-olefm comonomer, propylene homopolymer and/or propylene copolymer obtained from propylene and α-olefm comonomer such as ethylene and/or C4 to C’x a-olefm comonomer.

The article

The composition of the present invention is preferably used for the production of articles, more preferably of molded articles, yet more preferably of injection molded articles. Even more preferred is the use for the production of parts of washing machines or dishwashers as

-39well as automotive articles, especially of car interiors and exteriors, like bumpers, side trims, step assists, body panels, spoilers, dashboards, interior trims and the like.

The current invention also provides articles, more preferably molded articles, like injection molded articles, comprising, preferably comprising at least 60 wt.-%, more preferably at least 80 wt.-%, yet more preferably at least 95 wt.-%, like consisting of, the inventive composition. Accordingly the present invention is especially directed to parts of washing machines or dishwashers as well as to automotive articles, especially to car interiors and exteriors, like bumpers, side trims, step assists, body panels, spoilers, dashboards, interior trims and the like, comprising, preferably comprising at least 60 wt.-%, more preferably at least 80 wt.-%, yet more preferably at least 95 wt.-%, like consisting of, the inventive composition.

The present invention will now be described in further detail by the examples provided below.

EXAMPLES

1. Measuring methods

The following definitions of terms and determination methods apply for the above general description of the invention as well as to the below examples unless otherwise defined. Calculation of comonomer content of the first elastomeric propylene copolymer fraction, i.e. the polymer fraction produced in the second reactor (R2) of the first heterophasic propylene copolymer (HECO1):

w(PP2) wherein w(Ml) w(PP2) is the weight fraction [in wt.-%] of the first propylene polymer fraction, i.e. the polymer produced in the first reactor (Rl), is the weight fraction [in wt.-%] of the first elastomeric propylene copolymer fraction, i.e. the polymer produced in the second reactor (R2),

C(PP1)	is the comonomer content [in mol-%] of the first propylene polymer fraction, i.e. the polymer produced in the first reactor (Rl),
C(PP)	is the comonomer content [in mol-%] of the first propylene polymer and the first elastomeric propylene copolymer fraction, i.e. polymer produced in the first and second reactor (Rl + R2),
C(PP2)	is the calculated comonomer content [in mol-%] of the first elastomeric propylene copolymer fraction, i.e. the polymer produced in the second reactor (R2).

Calculation of comonomer content of the second elastomeric propylene copolymer fraction,

i.e. the polymer fraction produced in the second reactor (R2) of the first heterophasic propylene copolymer (HECO1):

C(PP) - w(PP12)x C(PP12) = C(PP3) (//) wherein

w(PP12)	is the weight fraction [in wt.-%] of the first propylene polymer fraction and the first elastomeric propylene copolymer fraction, i.e. the polymer produced in the first and second reactor (Rl + R2),
w(PP3)	is the weight fraction [in wt.-%] of second elastomeric propylene copolymer fraction, i.e. the polymer produced in the third reactor (R3),
C(PP12)	is the comonomer content [in mol-%] of the first propylene polymer fraction and the first elastomeric propylene copolymer fraction, i.e. the polymer produced in the first and second reactor (Rl + R2),
C(PP)	is the comonomer content [in mol-%] of the first propylene polymer fraction, the first elastomeric propylene copolymer fraction and the second elastomeric propylene copolymer fraction, i.e. polymer produced in the first, second and reactor (Rl + R2 + R3),
C(PP3)	is the calculated comonomer content [in mol-%] of the second elastomeric propylene copolymer fraction, i.e. the polymer produced in the second reactor (R2).

Calculation of the xylene cold soluble (XCS) content of the elastomeric propylene copolymer fraction, i.e. the polymer fraction produced in the second and third reactor (R2+R3) of the first heterophasic propylene copolymer (HECO1):

wherein

-41 XS(HECO) - w(PPl)x XS(PP1) ^V = XS(E) (III) w(E) is the weight fraction [in wt.-%] of the first propylene polymer fraction, i.e. the polymer produced in the first reactor (Rl), is the weight fraction [in wt.-%] of the elastomeric propylene copolymer fraction, i.e. the polymer produced in the second and third reactor (R2 + R3) is the xylene cold soluble (XCS) content [in wt.-%] of the first propylene polymer fraction, i.e. the polymer produced in the first reactor (Rl), is the xylene cold soluble (XCS) content [in wt.-%] of the first propylene polymer fraction, the first elastomeric propylene copolymer fraction and the second elastomeric propylene copolymer fraction, i.e. polymer produced in the first, second reactor and third reactor (Rl + R2 + R3), is the calculated xylene cold soluble (XCS) content [in wt.-%] of the elastomeric propylene copolymer fraction, i.e. the polymer produced in the second and third reactor (R2+R3).

Calculation of the xylene cold soluble (XCS) content of the first elastomeric propylene copolymer fraction, i.e. the polymer fraction produced in the second reactor (R2) of the first heterophasic propylene copolymer (HECO1):

XS(PP)- w(PPl)x XS(PPl) ^V = XS(PP2) (IV) w(PPl) w(E)

XS(PPl)

XS(HECO)

XS(E) wherein w(PP2) w(PPl) w(PP2)

XS(PPl)

XS(PP) is the weight fraction [in wt.-%] of the first propylene polymer fraction, i.e. the polymer produced in the first reactor (Rl), is the weight fraction [in wt.-%] of the first elastomeric propylene copolymer fraction, i.e. the polymer produced in the second reactor (R2) is the xylene cold soluble (XCS) content [in wt.-%] of the first propylene polymer fraction, i.e. the polymer produced in the first reactor (Rl), is the xylene cold soluble (XCS) content [in wt.-%] of the first propylene polymer fraction and the first elastomeric propylene copolymer fractions, i.e.

polymer produced in the first and second reactor (R1+R2),

-42XS(PP2) is the calculated xylene cold soluble (XCS) content [in wt.-%] of the first elastomeric propylene copolymer fraction, i.e. the polymer produced in the second reactor (R2).

Calculation of the xylene cold soluble (XCS) content of the second elastomeric propylene copolymer fraction, i.e. the polymer fraction produced in the third reactor (R3) of the first heterophasic propylene copolymer (HECO1):

XS(PP)- w(PP12)xXS(PP12) = XS(PP3) wherein

w(PP12)	is the weight fraction [in wt.-%] of the first propylene polymer fraction and the first elastomeric propylene copolymer fraction, i.e. the polymer produced in the first reactor and second reactor (R1+R2),
w(PP3)	is the weight fraction [in wt.-%] of the second elastomeric propylene copolymer fraction, i.e. the polymer produced in the third reactor (R3)
XS(PP12)	is the xylene cold soluble (XCS) content [in wt.-%] of the first propylene polymer fraction and the first elastomeric propylene copolymer fraction, i.e. the polymer produced in the first reactor and second (R1+R2),
XS(PP)	is the xylene cold soluble (XCS) content [in wt.-%] of the first propylene polymer fraction and the first and second elastomeric propylene copolymer fractions, i.e. polymer produced in the first, second reactor and third reactor (Rl + R2 + R3),
XS(PP3)	is the calculated xylene cold soluble (XCS) content [in wt.-%] of the second elastomeric propylene copolymer fraction, i.e. the polymer produced in the third reactor (R3).

Calculation of melt flow rate MFR2 (230 °C) of the first elastomeric propylene copolymer fraction, i.e. the polymer fraction produced in the second reactor (R2) of the first heterophasic propylene copolymer (HECO1):

[log(MFR(PP))-w(PPl) X log(MFP(PPl))l

MFF(PP2) = lol ^W(PP2) J (7/) wherein w(PPl) is the weight fraction [in wt.-%] of the first propylene polymer fraction, i.e.

the polymer produced in the first reactor (Rl),

w(PP2)	is the weight fraction [in wt.-%] of the first elastomeric propylene copolymer fraction, i.e. the polymer produced in the second reactor (R2),
MFR(PPl)	is the melt flow rate MFR2 (230 °C) [in g/lOmin] of the first propylene polymer fraction, i.e. the polymer produced in the first reactor (Rl),
MFR(PP)	is the melt flow rate MFR2 (230 °C) [in g/lOmin] of the first propylene polymer and the elastomeric first propylene copolymer fraction, i.e. the polymer produced in the first and second reactor (Rl + R2),
MFR(PP2)	is the calculated melt flow rate MFR2 (230 °C) [in g/lOmin] of the first propylene copolymer fraction, i.e. the polymer produced in the second reactor (R2).

Calculation of melt flow rate MFR2 (230 °C) of the second elastomeric propylene copolymer fraction, i.e. the polymer fraction produced in the third reactor (R3) of the first heterophasic propylene copolymer (HECO1):

[log(MF/?(PP))—w(PP12) X log(MFP(PP12))l MFR(PP3} = 101 ^W(PP3) J (7//) wherein

w(PP12)	is the weight fraction [in wt.-%] of the first propylene polymer fraction and the first elastomeric propylene copolymer fraction, i.e. the polymer produced in the first and second reactor (R1+R2),
w(PP3)	is the weight fraction [in wt.-%] of second elastomeric propylene copolymer fraction, i.e. the polymer produced in the third reactor (R3),
MFR(PP12)	is the melt flow rate MFR2 (230 °C) [in g/lOmin] of the first propylene polymer fraction and the first elastomeric propylene copolymer fraction, i.e. the polymer produced in the first and second reactor (R1+R2),
MFR(PP)	is the melt flow rate MFR2 (230 °C) [in g/lOmin] of the first propylene polymer, the first elastomeric propylene copolymer fraction and the second elastomeric propylene copolymer fraction, i.e. the polymer produced in the first, second and third reactor (Rl + R2 + R3),
MFR(PP3)	is the calculated melt flow rate MFR2 (230 °C) [in g/lOmin] of the second elastomeric propylene copolymer fraction, i.e. the polymer produced in the third reactor (R3).

-44Calculation of the intrinsic viscosity of the xylene soluble fraction of the first elastomeric propylene copolymer fraction, i.e. the polymer fraction produced in the second reactor (R2) of the first heterophasic propylene copolymer (HECO1):

IV(PP) — XCS(PPC)xIV(PPV) XCS(PP2') = IV(PP2') (VIIP) wherein

XCS(PPl)	is the xylene soluble fraction [in wt.-%] of the first propylene polymer fraction, i.e. the polymer produced in the first reactor (Rl),
XCS(PP2)	is the xylene soluble fraction [in wt.-%] of the first elastomeric propylene copolymer fraction, i.e. the polymer produced in the second reactor (R2),
IV(PPl)	is the intrinsic viscosity [in dl/g] of the xylene soluble fraction of the first propylene polymer fraction, i.e. the polymer produced in the first reactor (Rl),
IV(PP)	is the intrinsic viscosity [in dl/g] of the xylene soluble fraction of the first propylene polymer and the first elastomeric propylene copolymer fraction, i.e. polymer produced in the first and second reactor (Rl + R2),
IV(PP2)	is the calculated intrinsic viscosity [in dl/g] of the xylene soluble fraction of the first elastomeric propylene copolymer fraction, i.e. the polymer produced in the second reactor (R2).

Calculation of the intrinsic viscosity of the xylene soluble fraction of the second elastomeric propylene copolymer fraction, i.e. the polymer fraction produced in the third reactor (R3) of the first heterophasic propylene copolymer (HECO1):

IV(PP)- XCS(PP12)x IV(PP12)

XCS(PP3') = IV(PP3) wherein

XCS(PP12)	is the xylene soluble fraction [in wt.-%] of the first propylene polymer fraction and the first elastomeric propylene copolymer fraction, i.e. the polymer produced in the first and second reactor (Rl + R2),
XCS(PP3)	is the xylene soluble fraction [in wt.-%] of second elastomeric propylene copolymer fraction, i.e. the polymer produced in the third reactor (R3),
IV(PP12)	is the intrinsic viscosity [in dl/g] of the xylene soluble fraction of the first propylene polymer fraction and the elastomeric first propylene copolymer fraction, i.e. the polymer produced in the first and second reactor (Rl + R2),

-45 IV(PP) is the intrinsic viscosity [in dl/g] of the xylene soluble fraction of the first propylene polymer fraction, the first elastomeric propylene copolymer fraction and the second elastomeric propylene copolymer fraction, i.e. polymer produced in the first, second and reactor (R1 + R2 + R3),

IV(PP3) is the calculated intrinsic viscosity [in dl/g] of the xylene soluble fraction of the second elastomeric propylene copolymer fraction, i.e. the polymer produced in the third reactor (R3).

Calculation of comonomer content of the elastomeric propylene copolymer fraction, i.e. the polymer fraction produced in the second and third reactor (R2+R3) of the first heterophasic propylene copolymer (HECO1):

C(HECO) - w(PP)x C(PP) ΰ^Ε) -^{C(f) W} wherein w(PP) is the weight fraction [in wt.-%] of the first propylene polymer, i.e. polymer produced in the first reactor (Rl), w(E) is the weight fraction [in wt.-%] of the first elastomeric propylene copolymer fraction and the second elastomeric propylene copolymer fraction, i.e. of the polymer produced in the second and third reactor (R2 + R3),

C(PP) is the comonomer content [in mol -%] of the first propylene polymer, i.e.

polymer produced in the first reactor (Rl),

C(HECO) is the comonomer content [in mol -%] of the propylene copolymer, i.e. is the comonomer content [in mol -%] of the polymer obtained after polymerization in the third reactor (R3),

C(E) is the calculated comonomer content [in mol -%] of the first elastomeric propylene copolymer fraction and the second elastomeric propylene copolymer fraction, i.e. of the polymer produced in the second and third reactor (R2 + R3).

Calculation of comonomer content of the elastomeric copolymer fraction, i.e. the polymer fraction produced in the third reactor (R3), of the second heterophasic propylene copolymer (HECO2):

C(PP) - w(PP12)x C(PP12) w(PP3) = C(PP3) (X/)

-46wherein

w(PP12)	is the weight fraction [in wt.-%] of the first and second propylene polymer fraction, i.e. the polymer produced in the first and second reactor (R1+R2),
w(PP3)	is the weight fraction [in wt.-%] of the elastomeric propylene copolymer fraction, i.e. the polymer produced in the third reactor (R3),
C(PP12)	is the comonomer content [in mol-%] of the first and second propylene polymer fraction, i.e. the polymer produced in the first and second reactor (R1+R2),
C(PP)	is the comonomer content [in mol-%] of the first propylene polymer fraction, the second propylene polymer fraction and the elastomeric propylene copolymer fraction, i.e. polymer produced in the first, second and third reactor (R1 + R2 + R3),
C(PP3)	is the calculated comonomer content [in mol-%] of the elastomeric propylene copolymer fraction, i.e. the polymer produced in the third reactor (R3).

Calculation of the xylene cold soluble (XCS) content of the elastomeric propylene copolymer fraction, i.e. the polymer fraction produced in the third reactor (R3), second heterophasic propylene copolymer (HECO2):

XS(HECO) — w(PP12)%XS(PP12) -------------—------------= XS (E) (XII) w(E) wherein

w(PP12)	is the weight fraction [in wt.-%] of the first and second propylene polymer fraction, i.e. the polymer produced in the first and second reactor (R1+R2),
w(E)	is the weight fraction [in wt.-%] of the elastomeric propylene copolymer fraction, i.e. the polymer produced in the third reactor (R3)
XS(PP12)	is the xylene cold soluble (XCS) content [in wt.-%] of the first and second propylene polymer fraction, i.e. the polymer produced in the first and second reactor (R1+R2),
XS(HECO)	is the xylene cold soluble (XCS) content [in wt.-%] of the first propylene polymer fraction, the second propylene polymer fraction and the elastomeric propylene copolymer fraction, i.e. polymer produced in the first, second reactor and third reactor (R1 + R2 + R3),

-47XS(E) is the calculated xylene cold soluble (XCS) content [in wt.-%] of the elastomeric propylene copolymer fraction, i.e. the polymer produced in the second and third reactor (R2+3).

Calculation of melt flow rate MFR2 (230 °C) of the elastomeric propylene copolymer fraction, i.e. the polymer fraction produced in the third reactor (R3), second heterophasic propylene copolymer (HECO2):

[log(MFF(PF))-w(FF12) X log(MFF(PP12))l MF«(PP3) = 101 ^W(PP3) J (XIII) wherein

w(PP12)	is the weight fraction [in wt.-%] of the first and second propylene polymer fractions, i.e. the polymer produced in the first and second reactor (R1+R2),
w(PP3)	is the weight fraction [in wt.-%] of the elastomeric propylene copolymer fraction, i.e. the polymer produced in the third reactor (R3),
MFR(PP12)	is the melt flow rate MFR2 (230 °C) [in g/lOmin] of the first and second propylene fractions, i.e. the polymer produced in the first and second reactor (R1+R2),
MFR(PP)	is the melt flow rate MFR2 (230 °C) [in g/lOmin] of the first and second propylene polymer fractions and the elastomeric propylene copolymer fraction, i.e. the polymer produced in the first, second and third reactor (Rl + R2 + R3),
MFR(PP3)	is the calculated melt flow rate MFR2 (230 °C) [in g/lOmin] of the elastomeric propylene copolymer fraction, i.e. the polymer produced in the third reactor (R3).

Calculation of comonomer content of the elastomeric propylene copolymer fraction, i.e. the polymer fraction produced in the third reactor (R3), second heterophasic propylene copolymer (HECO2):

wherein

C(HECO) - w(PP)x C(PP) w(E) = C(E) w(E) w(PP) is the weight fraction [in wt.-%] of the first and second propylene polymer fractions, i.e. the polymer produced in the first and second reactor (R1+R2), is the weight fraction [in wt.-%] of the elastomeric propylene copolymer, i.e. of the polymer produced in the third reactor (R3),

-48 C(PP) is the comonomer content [in mol -%] of the first and second propylene polymer fractions, i.e. the polymer produced in the first and second reactor (R1+R2),

C(E) is the calculated comonomer content [in mol -%] of the elastomeric propylene copolymer fraction, i.e. of the polymer produced in the third reactor (R3).

MFR2 (230 °C) is measured according to ISO 1133 (230 °C, 2.16 kg load). MFR2 (190 °C) is measured according to ISO 1133 (190 °C, 2.16 kg load). MFR21 (190 °C) is measured according to ISO 1133 (190 °C, 21.6 kg load).

Quantification of microstructure by NMR spectroscopy

Quantitative nuclear-magnetic resonance (NMR) spectroscopy was used to quantify the comonomer content and comonomer sequence distribution of the polymers. Quantitative ^C^H} NMR spectra were recorded in the solution-state using a Bruker Advance III 400 NMR spectrometer operating at 400.15 and 100.62 MHz for 'Η and ¹³C respectively. All spectra were recorded using a ¹³C optimised 10 mm extended temperature probehead at 125 °C using nitrogen gas for all pneumatics. Approximately 200 mg of material was dissolved in 3 ml of /.T-tctrachlorocthanc-iL (TCE-0/2) along with chromium-(III)acetylacetonate (Cr(acac)’,) resulting in a 65 mM solution of relaxation agent in solvent (Singh, G., Kothari, A., Gupta, V., Polymer Testing 28 5 (2009), 475). To ensure a homogenous solution, after initial sample preparation in a heat block, the NMR tube was further heated in a rotatary oven for at least 1 hour. Upon insertion into the magnet the tube was spun at 10 Hz. This setup was chosen primarily for the high resolution and quantitatively needed for accurate ethylene content quantification. Standard single-pulse excitation was employed without NOE, using an optimised tip angle, 1 s recycle delay and a bi-level WALTZ 16 decoupling scheme (Zhou, Z., Kuemmerle, R., Qiu, X., Redwine, D., Cong, R., Taha, A., Baugh, D. Winniford, B., J. Mag. Reson. 187 (2007) 225; Busico, V., Carbonniere, P., Cipullo, R., Pellecchia, R., Severn, J., Talarico, G., Macromol. Rapid Commun. 2007, 28, 1128). A total of 6144 (6k) transients were acquired per spectra.

-49Quantitative ¹³C {¹H} NMR spectra were processed, integrated and relevant quantitative properties determined from the integrals using proprietary computer programs. All chemical shifts were indirectly referenced to the central methylene group of the ethylene block (EEE) at 30.00 ppm using the chemical shift of the solvent. This approach allowed comparable referencing even when this structural unit was not present. Characteristic signals corresponding to the incorporation of ethylene were observed Cheng, Η. N., Macromolecules 17 (1984), 1950).

For polypropylene homopolymers all chemical shifts are internally referenced to the methyl isotactic pentad (mmmm) at 21.85 ppm.

Characteristic signals corresponding to regio defects (Resconi, L., Cavallo, L., Fait, A., Piemontesi, F., Chem. Rev. 2000, 100, 1253; Wang, W-J., Zhu, S., Macromolecules 33 (2000), 1157; Cheng, Η. N., Macromolecules 17 (1984), 1950) or comonomer were observed.

The tacticity distribution was quantified through integration of the methyl region between 23.6-19.7 ppm correcting for any sites not related to the stereo sequences of interest (Busico, V., Cipullo, R., Prog. Polym. Sci. 26 (2001) 443; Busico, V., Cipullo, R., Monaco, G., Vacatello, M., Segre, A.L., Macromoleucles 30 (1997) 6251).

Specifically the influence of regio defects and comonomer on the quantification of the tacticity distribution was corrected for by subtraction of representative regio defect and comonomer integrals from the specific integral regions of the stereo sequences.

The isotacticity was determined at the pentad level and reported as the percentage of isotactic pentad (mmmm) sequences with respect to all pentad sequences: [mmmm] % = 100 * (mmmm / sum of all pentads )

The presence of 2,1 erythro regio defects was indicated by the presence of the two methyl sites at 17.7 and 17.2 ppm and confirmed by other characteristic sites.

Characteristic signals corresponding to other types of regio defects were not observed (Resconi, L., Cavallo, L., Fait, A., Piemontesi, F., Chem. Rev. 2000, 100, 1253).

The amount of 2,1 erythro regio defects was quantified using the average integral of the two characteristic methyl sites at 17.7 and 17.2 ppm:

P₂le = ( Ie6 + Ie8 ) / 2

-50The amount of 1,2 primary inserted propene was quantified based on the methyl region with correction undertaken for sites included in this region not related to primary insertion and for primary insertion sites excluded from this region:

P12= ΙθΗ3 + P12e

The total amount of propene was quantified as the sum of primary inserted propene and all other present regio defects:

Ptotal = P12 + P21e

The mole percent of 2,1 erythro regio defects was quantified with respect to all propene:

[2le] mol% = 100 * ( P₂i_e / Ptotai)

For copolymers characteristic signals corresponding to the incorporation of ethylene were observed (Cheng, Η. N., Macromolecules 17 (1984), 1950).

With regio defects also observed (Resconi, L., Cavallo, L., Fait, A., Piemontesi, F., Chem. Rev. 2000, 100, 1253; Wang, W-J., Zhu, S., Macromolecules 33 (2000), 1157; Cheng, Η. N., Macromolecules 17 (1984), 1950) correction for the influence of such defects on the comonomer content was required.

The comonomer fraction was quantified using the method of Wang et. al. (Wang, W-J., Zhu, S., Macromolecules 33 (2000), 1157) through integration of multiple signals across the whole spectral region in the ¹³C{¹H} spectra. This method was chosen for its robust nature and ability to account for the presence of regio-defects when needed. Integral regions were slightly adjusted to increase applicability across the whole range of encountered comonomer contents.

For systems where only isolated ethylene in PPEPP sequences was observed the method of Wang et. al. was modified to reduce the influence of non-zero integrals of sites that are known to not be present. This approach reduced the overestimation of ethylene content for such systems and was achieved by reduction of the number of sites used to determine the absolute ethylene content to:

E = O.5(SPP + Ξβγ + Ξβδ + 0.5(SaP + Say))

Through the use of this set of sites the corresponding integral equation becomes:

E = 0.5(I_h +Ig + 0.5(Ic + Id)) using the same notation used in the article of Wang et. al. (Wang, W-J., Zhu, S., Macromolecules 33 (2000), 1157). Equations used for absolute propylene content were not modified.

- 51 The mole percent comonomer incorporation was calculated from the mole fraction:

E [mol%] = 100 * fE

The weight percent comonomer incorporation was calculated from the mole fraction:

E [wt%] = 100 * (fE * 28.06) / ((fE * 28.06) + ((1-fE) * 42.08))

The comonomer sequence distribution at the triad level was determined using the analysis method of Kakugo et al. (Kakugo, M., Naito, Y., Mizunuma, K., Miyatake, T. Macromolecules 15 (1982) 1150). This method was chosen for its robust nature and integration regions slightly adjusted to increase applicability to a wider range of comonomer contents.

Number average molecular weight (M_n), weight average molecular weight (M_w) and molecular weight distribution (MWD)

Molecular weight averages (Mw, Mn), and the molecular weight distribution (MWD), i.e. the Mw/Mn (wherein Mn is the number average molecular weight and Mw is the weight average molecular weight), were determined by Gel Permeation

Chromatography (GPC) according to ISO 16014-4:2003 and ASTM D 6474-99. A PolymerChar GPC instrument, equipped with infrared (IR) detector was used with 3 x Olexis and lx Olexis Guard columns from Polymer Laboratories and 1 ,2,4-trichlorobenzene (TCB, stabilized with 250 mg/L 2,6-Di tert butyl-4-methyl-phenol) as solvent at 160 °C and at a constant flow rate of 1 mL/min. 200 pL of sample solution were injected per analysis. The column set was calibrated using universal calibration (according to ISO 16014-2:2003) with at least 15 narrow MWD polystyrene (PS) standards in the range of 0,5 kg/mol to 11 500 kg/mol. Mark Houwink constants for PS, PE and PP used are as described per ASTM D 6474-99. All samples were prepared by dissolving 5.0 - 9.0 mg of polymer in 8 mL (at 160 °C) of stabilized TCB (same as mobile phase) for 2.5 hours for PP or 3 hours for PE at max. 160°C under continuous gentle shaking in the autosampler of the GPC instrument. Nominal viscosity molecular weight (Mv) is calculated from the intrinsic viscosity [η] determined according to ASTM D 4020 as follows:

Mv = 5.37 x 10⁴ x [η]¹·³⁷

Intrinsic viscosity (IV) of propylene homopolymers and copolymers is measured according to DIN ISO 1628/1, October 1999 (in Decalin at 135 °C).

Density data of UHMWPE M2 and M3 is provided by the supplier Jingchem and is measured according to GB1033.

-52The xylene solubles (XCS, wt.-%): Content of xylene cold solubles (XCS) is determined at 25 °C according ISO 16152; first edition; 2005-07-01. The part which remains insoluble is the xylene cold insoluble (XCI) fraction.

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

The tensile modulus is measured according to ISO 527-2 (cross head speed = 50 mm/min; 23 °C) using injection molded specimens as described in EN ISO 1873-2 (dog bone shape, 4 mm thickness).

The impact strength is determined as Charpy Notched Impact Strength according to ISO 179-1 eA at +23 °C and at -20 °C on injection moulded specimens of 80 x 10 x 4 mm prepared according to EN ISO 1873-2.

The shrinkage on tool is determined on centre gated, injection moulded circular disks (diameter 180mm, thickness 3mm, having a flow angle of 355° and a cut out of 5°). Two specimens are moulded applying two different holding pressure times (10s and 20s respectively). The melt temperature at the gate is 260°C, and the average flow front velocity in the mould lOOmm/s. Tool temperature: 40 °C, back pressure: 600 bar.

Shrinkage (48h) was deterimed on film gate injection moulded plaques: One is a sector (radius 300 mm and opening angle of 20 °) and the other one a stripe (340x65 mm). The two specimens are injection moulded at the same time in different thicknesses and back pressures (2 mm and 300, 400, 500 bars; 2.8 mm and 300, 400, 500 bars; 3.5 mm and 300, 400, 500 bars). The melt temperature is 240 °C and the temperature of the tool 25 °C. Average flow front velocity is 3.0 ± 0.2 mm/s for the 2 mm tool, 3.5 + 0.2 mm/s for the 2.8 mm tool and.O ± 0.2 mm/s for the 3.5 mm tool. After the injection moulding process the shrinkage of the specimens is measured at 23 °C and 50 % humidity. The measurement interval is 48 hours after the injection moulding. To determine the shrinkage 83 and 71 measurement points (generated by eroded dots on the tool surface) of the sector and the stripe, respectively, are recorded with a robot. Both, in flow and cross flow shrinkage of the 2.8 mm thick plates exposed to a back pressure of 400 bars at 96 hours after the injection moulding process are reported as final results.

Puncture energy is determined in the instrumented falling weight test according to ISO 6603-2 using injection moulded plaques of 60x60x1 mm and a test speed of 2.2 m/s, clamped, lubricated striker with 20 mm diameter. The reported puncture energy results from an integral of the failure energy curve measured at (60x60x1 mm).

- 53 Scratch resistance: To determine the scratch resistance a Cross Hatch Cutter Model 420p, manufactured by Erichsen, was used. For the tests, plaques of 70x70x4 mm size were cut from a moulded grained (grain parameters: average grain size = 1mm, grain depth = 0,12 mm, conicity = 6°) plaque of size 140x200x4 mm. The minimum period between injection moulding of specimens and scratch-testing was 7 days. For testing the specimens must be clamped in a suitable apparatus as described above. Scratches are applied at a force of 10 N using a cylindrical metal pen with a ball shaped end (radius=0,5mm +- 0,01). A cutting speed of 1000 mm/min is used. A minimum of 20 scratches parallel to each other are brought up at a load of 10 N with a distance of 2 mm. The application of the scratches is repeated perpendicular to each other, so that the result is a scratching screen. The scratching direction shall be unidirectional. The scratch resistance is reported as the difference of the luminance AL of the unscratched from the scratched areas. AL values can be measured using a spectrophotometer that fulfils the requirements to DIN 5033. Measured AL Values must be below a maximum of 1.5. A detailed test description of the test method can be found in the article Evaluation of scratch resistance in multiphase PP blends by Thomas Koch and Doris Maehl, published in POLYMER TESTING 26 (2007), p. 927-936.

Volatile components: The volatile components (also light components, light compounds; which are mainly hydrocarbons and hydrocarbon derivatives, such as ketones, aldehydes and alcohols, containing from 6 to 20 carbon atoms and especially from 8 to 12 carbon atoms) were determined by using a gas chromatograph and a headspace method. The equipment was a Perkin Elmer gas chromatograph with a 30 m x 0.25 mm x 0.25 m column filled with DBwax (100% polyethylene glycol). A flame ionization detector (FID) was used, with hydrogen as a fuel gas. Helium at 18 psi was used as a carrier gas. After the injection of the sample, the oven temperature was maintained at 50 deg. C for 3 minutes, after which it was increased at a rate of 12 deg. C/min until it reached 200 deg. C. Then the oven was maintained at that temperature for 4 minutes, after which the analysis was completed. The calibration was carried out as follows: From 5 to 10 reference solutions were prepared, containing from 0.1 to 100 g of acetone dissolved in 1 litre of n-butanol. 4 1 of each solution was injected into a 20 ml injection flask, which was thermostated to 120 deg. C for 60 minutes and analysed. A calibration line for the area under the acetone peak vs. the concentration of acetone in nbutanol was thus obtained. The analysis was conducted as follows: The polymer sample (of 2 grams) was placed in the 20 ml injection flask, which was thermostated to 120 deg. C for 5

-54hours. A gas sample from the injection flask was then injected into the GC. Before the analysis, a blind run was conducted, where an injection from an empty flask was made. The hydrocarbon emission E was then calculated as follows:

(Λ-Β)

E =------- X 2 X 0.6204 k

Where E is the hydrocarbon emission as g carbon per gram of sample,

A is the total area under the sample peaks,

B is the total area under the blind run peaks, and k is the slope of the calibration line.

Fogging has been determined according to DIN75201, Part B on 2 mm thick compression molded plaques. Thermal treatment was performed at 100 °C for 16 hours. Fogging is expressed as a difference in weight before and after treatment.

Gloss: For determining optical properties, injection moulded plaques (60 x 60 x 2 mm) were produced. Gloss of the injection moulded plaques was measured according to DIN 67 530.

2. Examples

Preparation of the Catalysts

The catalyst used in the polymerization process for the first heterophasic propylene copolymer (HECO1) used in the inventive examples is the commercial catalyst ZN104 of Basell used along with dicyclopentyl dimethoxy silane (D-Donor) as donor. 80 mg of ZN104-catalyst are activated for 5 minutes with a mixture of Triethylaluminium (TEAL; solution in hexane 1 mol/1) and dicyclopentyl dimethoxy silane as donor (0.3 mol/1 in hexane) - in a molar ratio of 4 after a contact time of 5 min- and 10 ml hexane in a catalyst feeder. The molar ratio of TEAL and Ti of catalyst is 250. After activation the catalyst is spilled with 250 g propylene into the stirred reactor with a temperature of 23 C. Stirring speed is hold at 250 rpm. After 6 min prepolymerisation at 23 C temperature is increased to 70 °C in about 14 min. After holding that temperature for 1 hour polymerisation is stopped by flashing propylene and cooling to room temperature.

For the preparation of the catalyst used in the polymerization process of the second heterophasic copolymer (HECO2), 0.1 mol of MgC12 x 3 EtOH was suspended under inert conditions in 250 ml of decane in a reactor at atmospheric pressure. The solution was cooled to the temperature of-15°C 5 and 300 ml of cold TiC14 was added while maintaining the

- 55 temperature at said level. Then, the temperature of the slurry was increased slowly to 20°C. At this temperature, 0.02 mol of dioctylphthalate (DOP) was added to the slurry. After the addition of the phthalate, the temperature was raised to 135°C during 90 minutes and the slurry was allowed to stand for 60 minutes. Then, another 300 ml of TiC14 was added and 5 the temperature was kept at 135°C 10 for 120 minutes. After this, the catalyst was filtered from the liquid and washed six times with 300 ml heptane at 80°C. Then, the solid catalyst component was filtered and dried. Catalyst and its preparation concept is described in general e.g. in patent publications EP 491566, EP 591224 and EP 586390.

The catalyst was further modified (VCH modification of the catalyst). 35 ml of mineral oil 10 (Paraffinum Liquidum PL68) was added to a 125 ml stainless steel reactor followed by

0.82 g of triethyl aluminium (TEAL) and 0.33 g of dicyclopentyl dimethoxy silane (donor D) under inert conditions at room temperature. After 10 minutes 5.0 g of the catalyst prepared above (Ti content 1.4 wt.-%) was added and after additionally 20 minutes 5.0 g of vinylcyclohexane (VCH) was added. The temperature was increased to 60 °C during

30 minutes and was kept there for 20 hours. Finally, the temperature was decreased to 20 °C and the concentration of unreacted VCH in the oil/catalyst mixture was analysed and was found to be 200 ppm weight.

Table 1: Preparation of HECO1 and HECO2

		HECO1	HECO2
Prepolymerization
TEAL/Ti	[mol/mol]	220	200
TEAL/donor	[mol/mol]	30	6.7
Temperature	[°C]	20	30
res. time	M	0.1	0.1
Loop
Temperature	[°C]	70	85
Pressure	[kPa]	5520	55
Split	[%]	64	38
H2/C3 ratio	[mol/kmol]	15	0.64
C2/C3 ratio	[mol/kmol]	0	0
mfr₂	[g/lOmin]	85	40.0
XCS	[wt.-%]	2.0	1.0
C2 content	[mol-%]	0.0	0.0
GPR1
Temperature	[°C]	80	85
Pressure	[kPa]	1600	24
Split	[%]	13	44

H2/C3 ratio	[mol/kmol]	120	0
C2/C3 ratio	[mol/kmol]	510	0
MFR₂	[g/lOmin]	32	40.0
XCS	[wt.-%]	25	1.0
C2 content	[mol-%]	9.0	0.0
GPR 2
Temperature	[°C]	80	80
Pressure	[kPa]	1450	19
Split	[%]	23	18
C2/C3 ratio	[mol/kmol]	1400	580
H2/C2 ratio	[mol/kmol]	280	110
MFR₂	[g/lOmin]	18.0	20.0
XCS	[wt.-%]	29.0	17.5
IV (XCS)	[dl/gl	2.7	2.6
C2 (XCS)	[mol-%]	48.0	43.6
C2 content	[mol-%]	11.1	10.8

C2

H2/C3 ratio

C2/C3 ratio

H2/C2 ratio

GPR 1/2/3

Loop ethylene hydrogen / propylene ratio ethylene / propylene ratio hydrogen / ethylene ratio lst/2nd/3rd gas phase reactor Loop reactor

HECO1 and HECO2 were mixed in a twin-screw extruder with 0.2 wt.-% of Irganox B225 (l:l-blend of Irganox 1010 (Pentaerythrityl-tetrakis(3-(3’,5’-di-tert.butyl-4-hydroxytoluyl)propionate and tris (2,4-di-t-butylphenyl) phosphate) phosphite) of BASF AG, Germany) and 0.1 wt.-% calcium stearate, respectively.

Preparation of the composition (C)

HECO1, HECO2 and UHMWPE (inventive) or HD PE (comparative) were melt blended on a co-rotating twin screw extruder with the inorganic filler (F) in the amounts indicated in Table 2 below and 2.4 wt.-% of the black pigment CBMD-LD-11-A, 1.8 wt.-% of MB50001, L3 wt.-% of the white pigment Rifratene Weiss GH/894, 1.2 wt.-% of HC001A-B1, 0.25 wt.-% of the bisphenol A-epoxy resin Araldite GT 7072 by Huntsman, 0.25 wt.-% of Songnox 1010FF (pentaerythrityl-tetrakis(3-(3’,5’-di-tert. butyl-4-hydroxyphenyl)propionate) by Songwon, 0.20 wt.-% of Cyasorb UV-3808PP5 by Cytec and 0.10 wt.-% of Songnox 1680FF (tris (2.4-di-/-butylphcnyl) phosphite by Songwon. The polymer melt mixture was discharged and pelletized.

-57Table 2: Composition of comparative and inventive examples

		CE1	IE1	IE2	IE3
HECO1	[wt.-%]	52.5	52.5	52.5	52.5
HECO2	[wt.-%]	16.0	16.0	16.0	16.0
UHMWPE1	[wt.-%]		10.0
UHMWPE2	[wt.-%]			10.0
UHMWPE3	[wt.-%]				10.0
HDPE	[wt.-%]	10.0
Talc	[wt.-%]	14.0	14.0	14.0	14.0
Additives	[wt.-%]	7.5	7.5	7.5	7.5

UHMWPE1

UHMWPE2

UHMWPE3

HDPE

Talc is the commercial ethylene homopolymer M2 by Jingchem having a nominal viscosity molecular weight Mv of 2,750 kg/mol.

is the commercial ethylene homopolymer M3 by Jingchem having a nominal viscosity molecular weight Mv of 3,600 kg/mol.

is an ethylene homopolymer having a nominal viscosity molecular weight Mv of 2,054 kg/mol.

is the commercial high density polyethylene MG9641 by Borealis having a weight molecular weight Mw of 73 kg/mol.

is the commercial Talc Jetfine T1 CA of Luzenac

Additives is a masterbatch of the black pigment CBMD-LD-11-A, MB50-001, the white pigment Rifratene Weiss GH/894, HC001A-B1, the bisphenol Aepoxy resin Araldite GT 7072 by Huntsman, Songnox 1010FF (pentaerythrityl-tetrakis(3 -(3 ’ ,5 ’ -di-tert. butyl-4-hydroxyphenyl)-propionate) by Songwon, Cyasorb UV-3808PP5 by Cytec and Songnox 1680FF (tris (2.4-di-/-butyl phenyl) phosphite by Songwon as outlined above.

Table 3: Properties of comparative and inventive examples

		CE1	IE1	IE2	IE3
MFR	[g/10 min]	12.6	7.2	7.8	7.9
Ash content	[wt.-%]	14.2	13.8	14.4	14.0
Filler content (calculated)	[wt.-%]	14.2	13.8	14.3	14.0
Water content	[ppm]	183	153	169	168
Tensile modulus	[MPa]	1596	1457	1495	1449
Impact strength (23 °C)	[kJ/m²]	24.9	4.9	5.1	5.2
Impact strength (-20 °C)	[kJ/m²]	3.9	2.3	2.3	2.3
Puncture energy (23 °C)	[J]	36.9	10.6	9.8	10.4

Puncture energy (-20 °C)	[J]	29.6	2.8	2.9	3.4
Shrinkage on tool (isotropic)	[%]	0.78	1.23	1.18	1.22
Shrinkage on tool (anisotropic)	[%]	0.09	0.15	0.15	0.15
Shrinkage 48h (isotropic)	[%]	0.76	1.19	1.16	1.17
Shrinkage 48h (anisotropic)	[%]	0.09	0.13	0.13	0.14
Scratch test B (Delta L)	[-]	0.24	0.28	0.33	0.12
Scratch test B (Delta A)	[-]	-0.01	0.0	0.0	0.01
Scratch test B (Delta B)	[-]	0.02	0.04	0.04	0.05
Scratch test B (Delta E)	[-]	0.24	0.29	0.34	0.13
Volatile content	[pC/gl	18	15	15	15
Fogging (gravimetric)	[mg]	1.41	1.04	1.06	2.15
Gloss 60° (grain K09)	[%]	2.9	2.2	2.3	2.2
Gloss 60° (grain K36)	[%]	4.0	3.1	3.2	3.1
Gloss 60° (grain K85)	[%]	3.2	2.6	2.7	2.7

Claims

1. Polypropylene composition (C), comprising

a) a matrix being a first propylene polymer (Ml) and

a) a matrix being a second propylene polymer (M2) and

2. Polypropylene composition (C) according to claim 1, wherein the ultra high molecular weight polyethylene (UHMWPE) is an ethylene homopolymer.

3. Polypropylene composition (C) according to claim 1 or 2, wherein the ultra high molecular weight polyethylene (UHMWPE) has

i) a density of at least 920 g/cm3, and/or ii) amelt flow rate MFR21 (190 °C, 21.6 kg) below 2.0 g/10 min.

4. Polypropylene composition (C) according to any one of the preceding claims, having a melt flow rate MFR (190 °C, 2.16 kg) measured according to ISO 1133 in the range of 3.0 to 25.0 g/10 min.

5. Polypropylene composition (C) according to any one of the preceding claims, comprising

a) 40.0 to 60.0 wt.-% of the first heterophasic propylene copolymer (HECO1),

b) 10.0 to 25.0 wt.-% of the second heterophasic propylene copolymer (HECO2),

d) 7.0 to 20.0 wt.-% of the inorganic filler (F), based on the overall weight of the polypropylene composition (C).

6. Polypropylene composition (C) according to any one of the preceding claims, wherein the first heterophasic propylene copolymer (HECO1) and/or the second heterophasic propylene copolymer (HECO2) are copolymers of propylene and ethylene.

7. Polypropylene composition (C) according to any one of the preceding claims, wherein the first heterophasic propylene copolymer (HECO1) has

8. Polypropylene composition (C) according to any one of the preceding claims, wherein the xylene soluble fraction (XCS) of the first heterophasic propylene copolymer (HECO1) has

9. Polypropylene composition (C) according to any one of the preceding claims, wherein the matrix of the first heterophasic propylene copolymer (HECO1), i.e. the first propylene polymer (Ml), has a melt flow rate MFR (230 °C, 2.16 kg) measured according to ISO 1133 above 50.0 g/10 min.

10. Polypropylene composition (C) according to any one of the preceding claims, wherein the second heterophasic propylene copolymer (HECO2) has

11. Polypropylene composition (C) according to any one of the preceding claims, wherein the xylene soluble fraction (XCS) of the second heterophasic propylene copolymer (HECO2) has

12. Polypropylene composition (C) according to any one of the preceding claims, wherein the matrix of the second heterophasic propylene copolymer (HECO2), i.e. the second propylene polymer (M2), has a melt flow rate MFR (230 °C, 2.16 kg) measured according to ISO 1133 in the range of 15 to 60 g/10 min.

13. Polypropylene composition (C) according to any one of the preceding claims, wherein the inorganic filler (F) is talc.

14. Article, comprising the polypropylene composition (C) according to any one of claims 1 to 13.

15. Article according to claim 14, wherein the article is an injection moulded article, preferably an injection moulded automotive article.

Application No: GB 1719913.4

Claims searched: 1-15

Examiner:

Mr Robert Goodwill

Intellectual Property Office

Date of search: 15 May 2018

Patents Act 1977: Search Report under Section 17

Documents considered to be relevant:

Category Relevant to claims Identity of document and passage or figure of particular relevance A - WO 2017/060139 Al (BOREALIS AG), see EPODOC abstract A - US 2016/194486 Al (SANDHOLZER), see WPI abstract AN 2015-14468H A - WO 2017/041296 Al (BOROUGE COMPOUNDING SHANGHAI CO ), see WPI abstract AN 2017/18881V A - US 2016/185946 Al (SANDHOLZER), see WPI abstract AN 2015-14468J A - WO 2013/092615 Al (BOREALIS AG), see claim 1

Categories:

X Document indicating lack of novelty or inventive step A Document indicating technological background and/or state of the art. Y Document indicating lack of inventive step if P Document published on or after the declared priority date but combined with one or more other documents of before the filing date of this invention. same category. & Member of the same patent family E Patent document published on or after, but with priority date earlier than, the filing date of this application.

Field of Search:

Search of GB, EP, WO & US patent documents classified in the following areas of the UKCX :