# US 10,308,795 B2 · Heterophasic polypropylene with improved stiffness/impact balance

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 10,308,795 B2
- Document ID: US10308795B2
- Status: Granted
- Kind: B2
- Application number: 15/521,179
- Filed: 2015-10-16
- Published: 2017-11-02
- Granted: 2019-06-04
- Earliest claimed: 2014-10-27
- Assignees: Borealis AG
- Applicants: Borealis AG
- Inventors: Jingbo Wang; Pauli Leskinen; Johanna Lilja; Markus Gahleitner
- Web page: https://patentgrep.com/patent/US10308795B2

## CPC

- C08L 23/12: Polypropene
- C08F 2/001: {Multistage polymerisation processes characterised by a change in reactor conditions without deactivating the intermediate polymer (C08F295/00, C08F297/00 take precedence)}
- C08F 4/6492: {containing aliphatic unsaturation}
- C08F 4/651: Pretreating with non-metals or metal-free compounds
- C08F 210/06: Propene
- C08J 5/18: Manufacture of films or sheets
- C08K 5/0083: {Nucleating agents promoting the crystallisation of the polymer matrix}
- C08L 23/0815: {with aliphatic 1-olefins containing one carbon-to-carbon double bond}
- C08L 23/16: Ethylene-propylene or ethylene-propylene-diene copolymers
- C08F 210/16: Copolymers of ethene with alpha-alkenes, e.g. EP rubbers
- C08F 2500/12: Melt flow index or melt flow ratio
- C08F 2500/15: Isotactic
- C08F 2500/17: Viscosity
- C08J 2323/12: Polypropene
- C08J 2423/08: Copolymers of ethene (C08J2423/16 takes precedence)
- C08J 2423/14: Copolymers of propene (C08J2423/16 takes precedence)
- C08L 2205/02: containing two or more polymers of the same C08L -group
- C08L 2205/03: containing three or more polymers in a blend
- C08L 2205/24: Crystallisation aids
- C08L 2207/02: Heterophasic composition
- C08L 2207/06: Properties of polyethylene
- C08L 2308/00: Chemical blending or stepwise polymerisation process with the same catalyst
- C08L 2314/02: Ziegler natta catalyst
- C08L: COMPOSITIONS OF MACROMOLECULAR COMPOUNDS (compositions based on polymerisable monomers C08F, C08G; artificial filaments or fibres D01F; textile treating compositions D06)
- C08F: MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08J: WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H (working, e.g. shaping, of plastics B29)
- C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09)

## Abstract

Heterophasic polypropylene composition with an advantageous, respectively stiffness/impact balance and its use.

## Claims

### Claim 1

A heterophasic polypropylene composition comprising:
(A) 70 to 90 wt % of a crystalline isotactic propylene homopolymer matrix having a pentad concentration as determined by 13C-NMR spectroscopy of more than 96 mol % and a matrix melt flow rate (MFRM) as determined at 230° C. and 2.16 kg load according ISO 1133 in the range of 0.5 to 50 g/10 min,
(B) 10 to 30 wt % of a predominantly amorphous propylene copolymer with 32 to 50 wt % of ethylene and/or an α-olefin with 4-10 carbon atoms, being present in the composition as dispersed particles, and
(C) 0 to 5.0 wt % of a crystalline ethylene copolymer with an α-olefin with 3-10 carbon atoms being present in the composition as inclusions of the dispersed particles of (B),
(D) 0 to 1.0 wt % of an alpha nucleating agent for the α- and/or γ-phase of isotactic polypropylene,
said composition being further characterized by a total melt flow rate (MFRT) as determined at 230° C. and 2.16 kg load according ISO 1133 in the range of 0.5 to 45 g/10 min, a fraction soluble in xylene (XCS) determined at 25° C. according ISO 16152 in the range of 11 to 27 wt %, and ratio of MFRT/MFRM of ≥1.0, and
wherein said composition has a crystalline polypropylene content with a melting point (Tm1) from DSC analysis according ISO 11357 in the range of 160 to 170° C. whereby the associated melting enthalpy (Hm1) is in the range of 70 to 100 J/g and optionally a crystalline polyethylene content with a melting point (Tm2) from DSC analysis according ISO 11357 in the range of 105 to 130° C. whereby the associated melting enthalpyl (Hm2) is less than 7.0 J/g.

### Claim 2 (depends on 1)

A heterophasic polypropylene composition according to claim 1, wherein the intrinsic viscosity of the XCS fraction as measured according to DIN ISO 1628/1 in decalin at 135° C. is in the range of 1.2 to 4.5 dl/g and wherein the comonomer content, of the XCS fraction is in the range of 35.0 to 52.0 wt %.

### Claim 3 (depends on 1)

A heterophasic polypropylene composition according to claim 1, wherein a flexural modulus determined according to ISO 178 (FM) on an injection moulded specimen of 80×10×4 mm3 is in the range of 800 to 1700 MPa and furthermore fulfilling the inequation:
FM[MPa]>1660−33.4*XCS[wt %]
wherein XCS is the total fraction soluble in xylene (XCS) determined at 25° C. according ISO 16152 of the heterophasic polypropylene composition.

### Claim 4 (depends on 1)

A heterophasic polypropylene composition according to claim 1, having a Charpy notched impact strength at +23° C. as measured according to ISO 179-1eA in the range of 4.0 to 80.0 kJ/m2 and a Charpy notched impact strength at −20° C. as measured according to ISO 179-1eA in the range of 3.0 to 10.0 kJ/m2.

### Claim 5 (depends on 1)

A heterophasic polypropylene composition according to claim 1, having a total comonomer content defined as the sum of contents of ethylene and α-olefins with 4-10 carbon atoms in the range of 3.5 to 17.0 wt %.

### Claim 6 (depends on 1)

A heterophasic polypropylene composition according to claim 1, wherein at least two glass transition points (Tg) as determined by dynamic mechanical thermal analysis according ISO 6721-7, with one Tg (Tg(1)) associated to the crystalline isotactic propylene homopolymer matrix being in the range of −4 to 4° C. and another Tg (Tg(2)) associated to the predominantly amorphous propylene copolymer being in the range of −65 to −50° C.

### Claim 7 (depends on 1)

A heterophasic polypropylene composition according to claim 1, further comprising 0.0001 to 1.0 wt % of a nucleating agent for the α- and/or γ-phase of isotactic polypropylene and having a crystallization temperature from DSC analysis according ISO 11357 of more than 120° C.

### Claim 8 (depends on 1)

A heterophasic polypropylene composition according to claim 1, comprising a content of volatiles (VOC) as determined according to VDA 278:2002 of less than 250 ppm and furthermore fulfilling the inequation:
VOC[ppm]<110+7.0*MFRT[g/10min]
wherein MFRT is the total melt flow rate in g/10 min of said composition as determined at 230° C. and 2.16 kg load according ISO 1133.

### Claim 9 (depends on 1)

A heterophasic polypropylene composition according to claim 1, wherein the composition has been polymerized in the presence of:
a) a Ziegler-Natta catalyst comprising compounds (TC) of a transition metal of Group 4 to 6 of IUPAC, a Group 2 metal compound and an internal donor, wherein said internal donor is a non-phthalic compound;
b) a co-catalyst (Co), and
c) optionally an external donor (ED).

### Claim 10 (depends on 9)

A propylene polymer composition according to claim 9, wherein said internal donor is selected from the group comprising malonates, maleates, succinates, citraconates, glutarates, cyclohexene-1,2-dicarboxylates and benzoates, and any derivatives and/or mixtures thereof.

### Claim 11 (depends on 9)

A heterophasic polypropylene composition according to claim 9, wherein compounds (TC) of a transition metal of Group 4 to 6 is a titanium compound and wherein the molar ratio of co-catalyst (Co) to external donor (ED) [Co/ED] is in the range of 5 to 45, and the molar ratio of co-catalyst (Co) to titanium compound (TC) [Co/TC] is in the range of above 80 to 500.