Polymer composition

Abstract

This invention relates to compositions comprising: i) a first multiphase propylene copolymer (a) and / or a second multiphase propylene copolymer (b), ii) a high melt strength polypropylene, iii) a polyolefin-based elastomer, and iv) an inorganic filler, wherein the first multiphase propylene copolymer (a) has: a melt flow index (MFI) in the range of at least 5.6 dg / min and less than 50.0 dg / min, determined according to ISO 1133-1:2011 at 230°C with a 2.16 kg load, and a xylene-soluble portion in the range of 18.1 to 27.6 wt%, determined according to ISO 16152:2005, based on the total amount of the first multiphase propylene copolymer (a), wherein the xylene-soluble portion of the first multiphase propylene copolymer (a) has a value in the range of 2.9 to 4.8 wt%, measured according to ISO 1628-1:2009 in naphthalene at 135°C. The intrinsic viscosity is in the range of dl / g; wherein the second multiphase propylene copolymer (b) has: a melt flow index (MFI) in the range of 50.0 to 100 dg / min, determined at 230°C with a 2.16 kg load according to ISO 1133-1:2011, and a xylene-soluble portion in the range of 12.1 to 20.6 wt% based on the total amount of the second multiphase propylene copolymer (b), determined according to ISO 16152:2005, wherein the xylene-soluble portion of the second multiphase propylene copolymer (b) has an intrinsic viscosity in the range of 3.6 to 6.2 dl / g, measured at 135°C in naphthalene according to ISO 1628-1:2009.

Description

Technical Field

[0001] This invention relates to polymer compositions and foamed articles comprising such compositions. The invention also relates to methods for preparing said foamed articles, and to the use of the foamed articles in the manufacture of automotive parts. Background Technology

[0002] Foamed products, especially polypropylene-based foamed products, are widely used in the automotive industry due to their low density and excellent balance between impact resistance and stiffness.

[0003] WO2013178509A1 discloses a foamed article prepared from a composition comprising: (A) 30 to 85 wt% of a propylene-based component selected from propylene homopolymers, propylene copolymers, or multiphase propylene polymers, such first propylene-based component having a flexural modulus greater than 800 MPa as determined according to ISO 178; (B) 1 to 20 wt% of a multiphase propylene polymer; (C) 1 to 30 wt% of an ethylene-based plastide having a hardness (Shore A, ASTM D-2240) value equal to or less than 90 points; and (D) 5 to 30 wt% of talc.

[0004] WO2021130140A1 discloses a foamed article comprising a polymer composition including first and second multiphase propylene copolymers, inorganic fillers, and a polyolefin-based elastomer. WO2021130140A1 mentions that the foamed article has superior surface quality and excellent stiffness retention compared to a solid article made from the same materials. Summary of the Invention

[0005] The purpose of this invention is to provide a polymer composition that can be used to prepare foamed articles with a combination of good puncture impact behavior and good stiffness.

[0006] Therefore, the present invention provides a polymer composition comprising:

[0007] i) the first multiphase propylene copolymer (a) and / or the second multiphase propylene copolymer (b),

[0008] ii) High melt strength polypropylene,

[0009] iii) Polyolefin-based elastomers, and

[0010] iv) Inorganic fillers,

[0011] The first multiphase propylene copolymer (a) has the following characteristics:

[0012] According to ISO 1133-1:2011, the melt flow index (MFI) is determined at 230°C with a 2.16 kg load, in the range of at least 5.6 dg / min and less than 50.0 dg / min.

[0013] The xylene-soluble fraction, measured according to ISO 16152:2005, is in the range of 18.1 to 27.6 wt% based on the total amount of the first multiphase propylene copolymer (a), wherein:

[0014] The xylene-soluble portion of the first multiphase propylene copolymer (a) has an intrinsic viscosity in the range of 2.9 to 4.8 dl / g, measured at 135 °C in naphthalene according to ISO 1628-1:2009.

[0015] The second multiphase propylene copolymer (b) has the following characteristics:

[0016] According to ISO 1133-1:2011, the melt flow index (MFI) is determined at 230°C with a load of 2.16 kg in the range of 50.0 to 100 dg / min.

[0017] The xylene-soluble fraction, measured according to ISO 16152:2005, is in the range of 12.1 to 20.6% by weight based on the total amount of the second multiphase propylene copolymer (b).

[0018] The xylene-soluble portion of the second multiphase propylene copolymer (b) has an intrinsic viscosity in the range of 3.6 to 6.2 dl / g, measured at 135 °C in naphthalene according to ISO 1628-1:2009.

[0019] Surprisingly, the addition of high melt strength polypropylene to the composition was found to significantly improve puncture impact behavior while maintaining good stiffness.

[0020] The polymer composition according to the invention comprises a first multiphase propylene copolymer (a) and / or a second multiphase propylene copolymer (b). Preferably, the total amount of the first multiphase propylene copolymer (a) and the second multiphase propylene copolymer (b) is in the range of 30 to 80% by weight, for example, 50 to 75% by weight, based on the total amount of the polymer composition.

[0021] In some embodiments, the polymer composition according to the invention comprises a first multiphase propylene copolymer (a) and optionally a second multiphase propylene copolymer (b).

[0022] In some embodiments, the polymer composition according to the invention comprises a second multiphase propylene copolymer (b) and optionally a first multiphase propylene copolymer (a).

[0023] In some embodiments, the polymer composition according to the invention comprises a first multiphase propylene copolymer (a) and a second multiphase propylene copolymer (b). This results in a foamed article according to the invention having a very high surface quality. Preferably, the weight ratio between the first multiphase propylene copolymer (a) and the second multiphase propylene copolymer (b) is 1:10 to 10:1, for example, 1:10 to 1:1 or 1:1 to 10:1. In some embodiments, the weight ratio between the first multiphase propylene copolymer (a) and the second multiphase propylene copolymer (b) is 1:2 to 2:1, for example, 2:3 to 3:2.

[0024] The amount of the first multiphase propylene copolymer (a) may be, for example, in the range of 30 to 80% by weight, based on the total amount of the polymer composition, such as 50 to 75% by weight. This results in the foamed article according to the invention having particularly good puncture impact behavior.

[0025] The amount of the second multiphase propylene copolymer (b) may, for example, be in the range of 30 to 80% by weight, or, for example, 50 to 75% by weight, based on the total amount of the polymer composition. This is advantageous for the processability of the polymer composition used to prepare the foamed article according to the invention.

[0026] First multiphase propylene copolymer (a)

[0027] The first multiphase propylene copolymer (a) preferably comprises a first propylene polymer (a1) as a matrix and a first ethylene-α-olefin copolymer (a2) as a dispersed phase.

[0028] The amount of the first propylene polymer (a1) is preferably in the range of 68 to 92% by weight, more preferably in the range of 70 to 87% by weight, and even more preferably in the range of 72 to 83% by weight, based on the total amount of the first multiphase propylene copolymer (a).

[0029] The first propylene polymer (a1) in the first multiphase propylene copolymer (a) may be a propylene homopolymer and / or a propylene-α-olefin copolymer, wherein the α-olefin has 2 or 4 to 20 carbon atoms, for example, the propylene-α-olefin may be a propylene-ethylene copolymer or a propylene-butene copolymer. Preferably, the first propylene polymer (a1) in the first multiphase propylene copolymer (a) is a propylene homopolymer.

[0030] According to ISO 1133-1:2011, at 230°C with a 2.16 kg load, the melt flow index (MFI) of the first propylene polymer (a1) in the first multiphase propylene copolymer (a) is preferably in the range of 20 to 120 dg / min, more preferably in the range of 40 to 110 dg / min, and more preferably in the range of 60 to 90 dg / min.

[0031] The amount of the first ethylene-α-olefin copolymer (a2) is preferably in the range of 8 to 32% by weight, more preferably in the range of 13 to 30% by weight, and more preferably in the range of 17 to 28% by weight, based on the total amount of the first multiphase propylene copolymer (a).

[0032] In the first multiphase propylene copolymer (a), the amount of the ethylene-derived structural portion is preferably in the range of 35 to 49% by weight, more preferably in the range of 40 to 49% by weight, based on the total amount of the first ethylene-α-olefin copolymer (a2).

[0033] Preferably, the α-olefin in the first ethylene-α-olefin copolymer (a2) of the first multiphase propylene copolymer (a) is structurally derived from at least one α-olefin having 3 to 20 carbon atoms. For example, the first ethylene-α-olefin copolymer (a2) may be an ethylene-propylene copolymer, an ethylene-butene copolymer, an ethylene-hexene copolymer, an ethylene-octene copolymer, an ethylene-propylene-butene copolymer, or an ethylene-propylene-hexene copolymer. Preferably, the first ethylene-α-olefin copolymer (a2) of the first multiphase propylene copolymer (a) is an ethylene-propylene copolymer.

[0034] According to ISO 1133-1:2011, the MFI of the first multiphase propylene copolymer (a) is determined at 230°C with a load of 2.16 kg, in the range of at least 5.6 dg / min and less than 50.0 dg / min, preferably in the range of 8.6 to 45.1 dg / min, more preferably in the range of 11.2 to 25.3 dg / min, and more preferably in the range of 12.3 to 18.2 dg / min.

[0035] The first multiphase propylene copolymer (a) can be divided into a first xylene-soluble fraction (first CXS) and a first xylene-insoluble fraction (first CXI). According to ISO 16152:2005, the amount of the xylene-soluble fraction is in the range of 18.1 to 27.6% by weight, preferably in the range of 20.3 to 24.2% by weight, based on the total amount of the first multiphase propylene copolymer (a). The amount of the first xylene-insoluble fraction based on the total amount of the first multiphase propylene copolymer is calculated by the following equation:

[0036] First CXI = 100% by weight - First CXS

[0037] The intrinsic viscosity IV of the first xylene-insoluble portion (first CXI) of the first multiphase propylene copolymer (a), measured according to ISO 1628-3:2010. 第一CXI Preferably, it is in the range of 1.0 to 2.0 dl / g, more preferably in the range of 1.0 to 1.8 dl / g, and even more preferably in the range of 1.2 to 1.5 dl / g.

[0038] The intrinsic viscosity IV of the first xylene-soluble fraction (first CXS) of the first multiphase propylene copolymer (a) was measured according to ISO 1628-1:2009. 第一CXS The concentration is in the range of 2.9 to 4.8 dl / g, preferably in the range of at least 3.3 dl / g and less than 4.5 dl / g, and more preferably in the range of 3.8 to 4.3 dl / g.

[0039] Preferably, the intrinsic viscosity IV of the xylene-soluble portion (first CXS) of the first multiphase propylene copolymer (a) is... 第一CXS Intrinsic viscosity IV of the xylene-insoluble portion (first CXI) of the first multiphase propylene copolymer (a) 第一CXI The ratio between them is in the range of 2.0 to 3.5, preferably in the range of 2.2 to 3.0.

[0040] The first multiphase propylene copolymer (a) is preferably a non-viscosity-reducing cracked multiphase propylene copolymer. The term "non-viscosity-reducing cracked" is known in the art, but to avoid ambiguity, it means that the material has not been treated directly after polymerization to alter the polymer's molecular weight and / or molecular weight distribution. In other words, the non-viscosity-reducing cracked polymer has not been treated with peroxides, radiation, or any other initiator for chain scission reactions. The advantage of non-viscosity-reducing cracked polypropylene over viscosity-reducing cracked polypropylene is that the former is generally less affected by the release of low molecular weight materials, which are inherently generated during viscosity-reducing cracking and are undesirable for automotive applications. To avoid ambiguity, the term "reactor-grade" indicates that the copolymer is non-viscosity-reducing cracked. The first multiphase propylene copolymer (a) is preferably a reactor-grade multiphase propylene copolymer.

[0041] The method for producing the first multiphase propylene copolymer (a) is known in the art. Preferably, the first multiphase propylene copolymer (a) is produced in a sequential polymerization method comprising at least two reactors, and more preferably, the polypropylene of the present invention is produced in a sequential polymerization method comprising at least three reactors.

[0042] The catalyst used to prepare the first multiphase propylene copolymer (a) is also known in the art, such as a Ziegler-Natta catalyst or a metallocene catalyst. Preferably, the catalyst used to produce the first multiphase propylene copolymer is free of phthalates, for example, the catalyst comprises a group 4 to 6 transition metal compound of IUPAC, a group 2 metal compound and an internal donor, wherein the internal donor includes, but is not limited to, 1,3-diethers, such as 9,9-bis(methoxymethyl)fluorene, optionally substituted malonic acid esters, maleic acid esters, succinic acid esters, glutaric acid esters, benzoic acid esters, cyclohexene-1,2-dicarboxylic acid esters, benzoic acid esters, citrate esters, aminobenzoic acid esters, silyl esters and their derivatives and / or mixtures.

[0043] For example, the catalyst used to prepare the first multiphase propylene copolymer (a) is a Ziegler-Natta catalyst comprising a main catalyst, at least one external donor, a co-catalyst, and optionally an internal donor, wherein the external electron donor is selected from the group consisting of: having according to formula III (R 90 )2N-Si(OR 91 Compounds with the structure of )3, having the structure according to formula IV: (R 92 )Si(OR 93 Compounds with a structure of 3, and mixtures thereof,

[0044] Where R 90 R 91 R 92 and R 93 Each of the groups is independently a straight-chain, branched or cyclic, substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, preferably a straight-chain unsubstituted alkyl group having 1 to 8 carbon atoms, preferably ethyl, methyl or n-propyl.

[0045] In one implementation, R 90 and R 91 Each is an ethyl group (the compound of formula III is diethylaminotriethoxysilane, DEATES). In another embodiment, R 92 It is n-propyl and R 93 Each is an ethyl group (the compound of formula IV is n-propyltriethoxysilane, nPTES), or in another embodiment, R 92 It is n-propyl and R 93 Each is methyl (the compound of formula IV is n-propyltrimethoxysilane, nPTMS).

[0046] Preferably, the first multiphase propylene copolymer (a) is formed by comprising a Ziegler-Natta catalyst and a mixture selected from those having formula III: (R 90 )2N-Si(OR 91 Compounds with the structure of )3, having the structure according to formula IV: (R92 )Si(OR 93 The catalyst system is prepared by using at least one external electron donor of compounds and mixtures thereof with the structure of )3.

[0047] "Procatalyst" is a well-known term in the field of Ziegler-Natta catalyst technology and is considered to be a substance capable of converting a main catalyst into an active polymerization catalyst. Generally, a procatalyst is an organometallic compound containing a metal from Groups 1, 2, 12, or 13 of the periodic system (Handbook of Chemistry and Physics, 70th edition, CRC Press, 1989-1990). Procatalysts can include any compound known in the art as a "procatalyst," such as hydrides, alkylates, or arylates of aluminum, lithium, zinc, tin, cadmium, beryllium, magnesium, and combinations thereof. The co-catalyst can be a hydrocarbon-based aluminum co-catalyst, such as triisobutylaluminum, trihexylaluminum, diisobutylaluminum hydride, dihexylaluminum hydride, isobutyl dihydrogen hydride, hexyl dihydrogen hydride, diisobutylhexylaluminum, isobutyldihexylaluminum, trimethylaluminum, triethylaluminum, tripropylaluminum, triisopropylaluminum, tri-n-butylaluminum, trioctylaluminum, tridecylaluminum, tri(dodecyl)aluminum, tribenzylaluminum, triphenylaluminum, trinaphthylaluminum, and trimethylaluminum. In embodiments, the co-catalyst is selected from triethylaluminum, triisobutylaluminum, trihexylaluminum, diisobutylaluminum hydride, and dihexylaluminum hydride. More preferably, it is trimethylaluminum, triethylaluminum, triisobutylaluminum, and / or trioctylaluminum. Most preferably, it is triethylaluminum (abbreviated as TEAL). The cocatalyst can also be a hydrocarbon-based aluminum compound, such as tetraethylaluminoxane, methylaluminoxane, isobutylaluminoxane, tetraisobutylaluminoxane, diethylethoxyaluminum, diisobutylaluminum chloride, methylaluminum chloride, diethylaluminum chloride, ethylaluminum chloride, and dimethylaluminum chloride, preferably TEAL.

[0048] For example, the main catalyst can be prepared by a method comprising the steps of providing a magnesium-based support, contacting the magnesium-based support with a Ziegler-Natta type catalyst, an internal donor, and an activator to produce the main catalyst. For example, an improved method for preparing the main catalyst is disclosed in Dow's US 5,093,415. Preferably, the main catalyst is a titanium-containing compound.

[0049] In the context of this invention, the molar ratio of Si to Ti in the catalyst system is preferably in the range of 0.1 to 40, more preferably in the range of 0.1 to 20, even more preferably in the range of 1 to 20, and most preferably in the range of 2 to 10. Preferably, the molar ratio of Al to Ti in the catalyst system is in the range of 5 to 500, more preferably in the range of 15 to 200, more preferably in the range of 30 to 160, and most preferably in the range of 50 to 140.

[0050] In one implementation, the molar ratio between Si and Ti is the molar ratio between the external donor and the main catalyst.

[0051] In one implementation, the molar ratio between Al and Ti is the molar ratio between the co-catalyst and the main catalyst.

[0052] Second multiphase propylene copolymer (b)

[0053] The second multiphase propylene copolymer (b) preferably comprises a second propylene polymer (b1) as a matrix and a second ethylene-α-olefin copolymer (b2) as a dispersed phase.

[0054] The amount of the second propylene polymer (b1) is preferably in the range of 65 to 90% by weight, more preferably in the range of 79 to 88% by weight, based on the total amount of the second multiphase propylene copolymer (b).

[0055] The second propylene polymer (b1) in the second multiphase propylene copolymer (b) may be a propylene homopolymer and / or a propylene-α-olefin copolymer, wherein the α-olefin has 2 or 4 to 20 carbon atoms, for example, the propylene-α-olefin may be a propylene-ethylene copolymer or a propylene-butene copolymer. Preferably, the second propylene polymer (b1) in the second multiphase propylene copolymer (b) is a propylene homopolymer.

[0056] According to ISO 1133-1:2011, measured at 230°C with a 2.16 kg load, the MFI (melt flow index) of the second propylene polymer (b1) in the second multiphase propylene copolymer (b) is preferably in the range of 20 to 52.0 dg / min, more preferably in the range of 50 to 31.0 dg / min, and more preferably in the range of 14.0 to 26.0 dg / min.

[0057] The amount of the second ethylene-α-olefin copolymer (b2) is in the range of 10 to 35% by weight, preferably in the range of 12 to 21% by weight, based on the total amount of the second multiphase propylene copolymer (b).

[0058] In the second multiphase propylene copolymer (b), the amount of the ethylene-derived structural portion is preferably in the range of 35 to 49% by weight, based on the total amount of the second ethylene-α-olefin copolymer (b2).

[0059] The α-olefin structural portion of the second ethylene-α-olefin copolymer (b2) in the second multiphase propylene copolymer (b) is preferably derived from at least one α-olefin having 3 to 20 carbon atoms. For example, the second ethylene-α-olefin copolymer (b2) may be an ethylene-propylene copolymer, an ethylene-butene copolymer, an ethylene-hexene copolymer, an ethylene-octene copolymer, an ethylene-propylene-butene copolymer, or an ethylene-propylene-hexene copolymer. Preferably, the second ethylene-α-olefin copolymer (b2) in the second multiphase propylene copolymer (b) is an ethylene-propylene copolymer.

[0060] Preferably, the MFI of the second multiphase propylene copolymer (b) is in the range of 50.0 to 100 dg / min, more preferably in the range of 55.0 to 90.0 dg / min, and more preferably in the range of 60.0 to 83.0 dg / min, as determined by ISO 1133-1:2011 at 230°C with a load of 2.16 kg.

[0061] The second multiphase propylene copolymer (b) can be divided into a second xylene-soluble portion (second CXS) and a second xylene-insoluble portion (second CXI). As determined according to ISO 16152:2005, the amount of the second xylene-soluble portion is preferably in the range of 12.1 to 20.6% by weight, more preferably in the range of 12.5 to 20.0% by weight, and even more preferably in the range of 13.0 to 18.0% by weight, based on the total amount of the second multiphase propylene copolymer (b).

[0062] The intrinsic viscosity IV of the second xylene-insoluble portion (second CXI) of the second multiphase propylene copolymer (b), measured according to ISO 1628-3:2010. 第二CXI Preferably, it is in the range of 1.0 to 2.0 dl / g, more preferably in the range of 1.0 to 1.8 dl / g, and even more preferably in the range of 1.2 to 1.5 dl / g.

[0063] The intrinsic viscosity IV of the second xylene-soluble fraction (second CXS) of the second multiphase propylene copolymer (b) measured in naphthalene at 135°C according to ISO 1628-1:2009. 第二CXS Preferably in the range of 3.6 to 6.2 dl / g, more preferably in the range of 4.5 to 5.8 dl / g.

[0064] Preferably, the intrinsic viscosity IV of the xylene-soluble portion (second CXS) of the first multiphase propylene copolymer (a) 第二CXSIntrinsic viscosity IV of the xylene-insoluble portion (second CXI) of the second multiphase propylene copolymer (a) 第二CXI The ratio between them is in the range of 3.1 to 7.2, preferably in the range of 3.2 to 5.1.

[0065] The second multiphase propylene copolymer (b) is preferably a reactor-grade multiphase propylene copolymer.

[0066] The second multiphase propylene copolymer (b) can be produced using methods and catalysts known in the art.

[0067] In one embodiment, the second multiphase propylene copolymer (b) is produced using the same method as the first multiphase propylene copolymer (a).

[0068] In one embodiment, the second multiphase propylene copolymer (b) is produced using the same catalyst as the first multiphase propylene copolymer (a).

[0069] Optional third multiphase propylene copolymer

[0070] The polymer composition according to the invention may contain a third multiphase propylene copolymer (c).

[0071] The third multiphase propylene copolymer (c) preferably comprises a third propylene polymer (c1) as a matrix and a third ethylene-α-olefin copolymer (c2) as a dispersed phase.

[0072] The amount of the third propylene polymer (c1) is preferably in the range of 65 to 81% by weight, based on the total amount of the third multiphase propylene copolymer (c).

[0073] The third propylene polymer (c1) in the third multiphase propylene copolymer (c) may be a propylene homopolymer and / or a propylene-α-olefin copolymer, wherein the α-olefin has 2 or 4 to 20 carbon atoms, for example, the propylene-α-olefin may be a propylene-ethylene copolymer or a propylene-butene copolymer. Preferably, the third propylene polymer (c1) in the third multiphase propylene copolymer (c) is a propylene homopolymer.

[0074] According to ISO 1133-1:2011, measured at 230°C with a 2.16 kg load, the MFI (melt flow index) of the third propylene polymer (c1) in the third multiphase propylene copolymer (c) is preferably in the range of 20 to 150 dg / min, more preferably in the range of 50 to 100 dg / min, and more preferably in the range of 60 to 85 dg / min.

[0075] The amount of the third ethylene-α-olefin copolymer (c2) is in the range of 19 to 35% by weight, preferably in the range of 25 to 30% by weight, based on the total amount of the third multiphase propylene copolymer (c).

[0076] In the third multiphase propylene copolymer (c), the amount of the ethylene-derived structural portion is preferably in the range of 55 to 68% by weight, based on the total amount of the third ethylene-α-olefin copolymer (c2).

[0077] The α-olefin structural portion of the third ethylene-α-olefin copolymer (c2) in the third multiphase propylene copolymer (c) is preferably derived from at least one α-olefin having 3 to 20 carbon atoms. For example, the third ethylene-α-olefin copolymer (c2) may be an ethylene-propylene copolymer, an ethylene-butene copolymer, an ethylene-hexene copolymer, an ethylene-octene copolymer, an ethylene-propylene-butene copolymer, or an ethylene-propylene-hexene copolymer. Preferably, the third ethylene-α-olefin copolymer (c2) in the third multiphase propylene copolymer (c) is an ethylene-propylene copolymer.

[0078] Preferably, the MFI of the third multiphase propylene copolymer (c) is in the range of 10 to 100 dg / min, more preferably in the range of 15 to 80 dg / min, and more preferably in the range of 23 to 65 dg / min, as determined by ISO 1133-1:2011 at 230°C with a load of 2.16 kg.

[0079] The third multiphase propylene copolymer (c) can be divided into a third xylene-soluble portion (third CXS) and a third xylene-insoluble portion (third CXI). The amount of the third xylene-soluble portion, as determined according to ISO 16152:2005, is preferably in the range of 10 to 27% by weight, more preferably in the range of 15 to 23% by weight, based on the total amount of the third multiphase propylene copolymer (c).

[0080] The intrinsic viscosity IV of the third xylene-insoluble fraction (third CXI) of the third multiphase propylene copolymer (c) was measured according to ISO 1628-3:2010. 第三CXI Preferably, it is in the range of 1.0 to 2.0 dl / g, more preferably in the range of 1.0 to 1.8 dl / g, and even more preferably in the range of 1.2 to 1.5 dl / g.

[0081] The intrinsic viscosity IV of the third xylene-soluble fraction (third CXS) of the third multiphase propylene copolymer (c) measured in naphthalene at 135°C according to ISO 1628-1:2009. 第三CXSPreferably, it is in the range of 1.7 to 2.8 dl / g, more preferably in the range of 1.9 to 2.7 dl / g, and even more preferably in the range of 2.0 to 2.5 dl / g.

[0082] Intrinsic viscosity IV of the xylene-soluble portion (third CXS) of the third multiphase propylene copolymer (c) 第三CXS Intrinsic viscosity IV of the xylene-insoluble portion (third CXI) of the third multiphase propylene copolymer (c) 第三CXI The ratio between them is in the range of 1.1 to 1.9, preferably in the range of 1.5 to 1.8.

[0083] The third multiphase propylene copolymer (c) is preferably a reactor-grade multiphase propylene copolymer.

[0084] The third multiphase propylene copolymer (c) can be produced using methods and catalysts known in the art.

[0085] In one embodiment, the third multiphase propylene copolymer (c) is produced using the same method as the first multiphase propylene copolymer (a).

[0086] In one embodiment, the third multiphase propylene copolymer (c) is produced using the same catalyst as the first multiphase propylene copolymer (a).

[0087] The amount of the third multiphase propylene copolymer (c) may, for example, be in the range of 5.0 to 40% by weight, or 10 to 35% by weight, based on the total amount of the polymer composition.

[0088] Preferably, the total amount of the first multiphase propylene copolymer (a), the second multiphase propylene copolymer (b), and the third multiphase propylene copolymer (c) is at least 45% by weight, preferably at least 50% by weight, and more preferably at least 55% by weight, based on the total amount of the polymer composition.

[0089] In some preferred embodiments, the polymer composition according to the invention comprises a first multiphase propylene copolymer (a) and a third multiphase propylene copolymer (c). Preferably, the total amount of the first multiphase propylene copolymer (a) and the third multiphase propylene copolymer (c) is at least 45% by weight, preferably at least 50% by weight, and more preferably at least 55% by weight, based on the total amount of the polymer composition.

[0090] In some preferred embodiments, the polymer composition according to the invention comprises a second multiphase propylene copolymer (b) and a third multiphase propylene copolymer (c). Preferably, the total amount of the second multiphase propylene copolymer (b) and the third multiphase propylene copolymer (c) is at least 45% by weight, preferably at least 50% by weight, and more preferably at least 55% by weight, based on the total amount of the polymer composition.

[0091] High melt strength polypropylene

[0092] The polymer composition comprises high melt strength polypropylene (HMS-PP). Preferably, the amount of high melt strength polypropylene is 1.0 to 10% by weight based on the total amount of the polymer composition, for example, 3.0 to 7.0% by weight.

[0093] High melt strength polypropylene is branched, and thus differs from linear polypropylene in that the polypropylene backbone contains side chains, while unbranched polypropylene (i.e., linear polypropylene) does not. These side chains have a significant impact on the rheology of polypropylene. Therefore, linear polypropylene and high melt strength polypropylene can be clearly distinguished by their flow behavior under stress.

[0094] Branching can typically be achieved by using a specific catalyst (i.e., a specific unit site catalyst) or by chemical modification. For the preparation of branched polypropylene obtained by using a specific catalyst, refer to EP 1 892 264. For branched polypropylene obtained by chemical modification, refer to EP 0 879 830 A1. In such cases, branched polypropylene is also referred to as high melt strength polypropylene.

[0095] A suitable example of a commercially available product of high melt strength polypropylene is that it can be marketed under the trade name Daploy. TM Purchased from Borealis AG, such as Daploy TM WB140HMS.

[0096] Another suitable example of a commercially available product of high melt strength polypropylene is Achieve from Exxon Mobil. TM Advanced PP6302E1.

[0097] Preferably, the high melt strength polypropylene has a branching index g' of less than 1.00, more preferably less than 0.90, more preferably less than 0.80, and more preferably less than 0.75.

[0098] For example, EP1847555A1 explains the branching index g'. The branching index g' defines the degree of branching and is related to the amount of branching in the polymer. The branching index g' is defined as g'=[IV] br / [IV] lin Where g' is the branching index, [IV br [IV] is the intrinsic viscosity of branched polypropylene. linThis is the intrinsic viscosity of linear polypropylene with the same weight-average molecular weight (within ±10%) as the branched polypropylene. Therefore, a low g' value is an indicator of a highly branched polymer. In other words, if the g' value decreases, the branching of the polypropylene increases. In this context, refer to BH Zimm and WH Stockmeyer, J. Chem. Phys. 17, 1301 (1949). This document is incorporated herein by reference. The intrinsic viscosity required to determine the branching index g' was measured according to DIN ISO 1628 / 1, October 1999 (in naphthalene at 135°C).

[0099] Preferably, the high melt strength polypropylene has a melt strength of ≥ 30 cN. In this document, the melt strength of the high melt strength polypropylene is defined according to ISO 16790:2005 at 200°C using a cylindrical capillary tube with a length of 20 mm and a width of 2 mm, an initial velocity v0 of 9.8 mm / s, and a melt speed of 6 mm / s. 2 It is measured by acceleration.

[0100] High melt strength polypropylene with a melt strength ≥ 30 cN can be obtained, for example, by the method disclosed in WO2009 / 003930A1. WO2009 / 003930A1 discloses an irradiated polymer composition comprising at least one polyolefin resin and at least one non-phenolic stabilizer, wherein the irradiated polymer composition is produced by a method comprising mixing a polyolefin resin with a non-phenolic stabilizer and irradiating the mixture in a reduced oxygen environment. Additionally, high melt strength polypropylene with a melt strength ≥ 45 cN is available from SABIC as SABIC® PP UMS 561P (as of February 18, 2021).

[0101] Preferably, the high melt strength polypropylene is prepared by the following method:

[0102] a) Irradiating polypropylene having at least one non-phenolic stabilizer, preferably wherein the non-phenolic stabilizer is selected from the group consisting of hindered amines, wherein irradiation with an electron beam of ≥ 2.0 and ≤ 20 megalads in a hypoxic environment is sufficient for obtaining long-chain branched polypropylene, wherein the amount of active oxygen is ≤ 15% by volume relative to the total volume of the hypoxic environment, and

[0103] b) Deactivate free radicals in long-chain branched polypropylene to form high melt strength polypropylene.

[0104] How to deactivate free radicals is known in the art, for example by heating, as described in WO2009003930A1.

[0105] Examples of non-phenolic stabilizers are known in the art and are disclosed, for example, on pages 37-60 of WO2009 / 003930A1, which is incorporated herein by reference. Preferably, the non-phenolic stabilizer is selected from the group consisting of hindered amines. More preferably, the non-phenolic stabilizer comprises at least one hindered amine selected from the group consisting of Chimassorb® 944, Tinuvin® 622, Chimassorb® 2020, Chimassorb® 119, Tinuvin® 770, and mixtures thereof, which is alone or in combination with N,N-di(hydrogenated tallow)amine (Irgastab® FS-042), N,N-dialkylhydroxylamine produced by direct oxidation of N,N-di(hydrogenated tallow)amine (Irgastab® FS-042), N-octadecyl-α-heptadecanyl nitrone, Genox™ EP, di(C16-C18)alkylmethylamine oxide, 3-(3,4-dimethylphenyl)-5,7-di-tert-butyl-benzofuran-2-one, and Irganox® HP-136. (BFl) and mixtures thereof contain at least one hydroxylamine, nitrone, amine oxide, or benzofuranone, and the aforementioned components are alone or in combination with at least one organophosphite or phosphonite selected from tris(2,4-di-tert-butylphenyl) phosphite (Irgafos® 168). Even more preferably, the non-phenolic stabilizers of this subject matter may include those described in U.S. Patents 6,664,317 and 6,872,764 (both of which are incorporated herein by reference in their entirety).

[0106] Preferably, the melt strength of the high melt strength polypropylene is ≥ 37 cN, more preferably ≥ 40 cN, more preferably ≥ 45 cN, more preferably ≥ 50 cN, more preferably ≥ 55 cN, even more preferably ≥ 60 cN, most preferably ≥ 65 cN, and / or preferably the melt strength of the high melt strength polypropylene is ≤ 100 cN, for example ≤ 95 cN, for example ≤ 90 cN, for example ≤ 87 cN.

[0107] In this article, "polypropylene" refers to propylene homopolymer, copolymer of propylene and α-olefin, or multiphase propylene copolymer.

[0108] Preferably, the high melt strength polypropylene is a polypropylene selected from the group consisting of propylene homopolymers and propylene copolymers, wherein the propylene copolymer comprises a structural portion derived from propylene and one or more comonomers selected from the group consisting of ethylene and α-olefins having ≥ 4 and ≤ 12 carbon atoms.

[0109] Preferably, the propylene copolymer comprises a structural portion derived from one or more comonomers selected from the group consisting of ethylene and α-olefins having ≥ 4 and ≤ 12 carbon atoms, in an amount of ≤ 10% by weight based on the propylene copolymer, for example, ≥ 1.0% and ≤ 7.0% by weight, wherein the weight percentage is calculated using... 13 Measured by C NMR. For example, the propylene copolymer comprises a structural moiety derived from one or more comonomers selected from the group consisting of ethylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-decene and 1-dodecene, preferably a structural moiety derived from ethylene.

[0110] Polypropylene and methods for synthesizing polypropylene are known. Propylene homopolymers are obtained by polymerizing propylene under suitable polymerization conditions. Propylene copolymers are obtained by copolymerizing propylene with one or more other comonomers (e.g., ethylene) under suitable polymerization conditions. The preparation of propylene homopolymers and copolymers is described, for example, in Moore, EP (1996) Polypropylene Handbook. Polymerization, Characterization, Properties, Processing, Applications, Hanser Publishers, New York.

[0111] Propylene homopolymers, propylene copolymers, and multiphase propylene copolymers can be prepared by any known polymerization technique and using any known polymerization catalyst system. For details on the technique, refer to slurry, solution, or gas-phase polymerization; for details on the catalyst system, refer to Ziegler-Natta, metallocene, or single-point catalyst systems. All of these are known in the art.

[0112] Preferably, according to ASTM D1238 (2013) at a temperature of 230°C and a load of 2.16 kg, the high melt strength polypropylene has a melt flow rate of ≥ 0.50 and ≤ 8.0 g / 10 min, more preferably ≥ 0.70 and ≤ 5.0 g / 10 min, and most preferably ≥ 1.0 and ≤ 4.0 g / 10 min.

[0113] Preferably, the high melt strength polypropylene has a VOC value of ≤ 250 µg / g, preferably ≤ 50 µg / g, as determined by VDA278 (2011-10), and / or an FOG value of ≤ 500 µg / g, preferably ≤ 100 µg / g, as determined by VDA278 (2011-10).

[0114] Preferably, the high melt strength polypropylene has a molecular weight distribution of Mw / Mn of 5 to 20, more preferably 7 to 17, and most preferably 10 to 15. Mw and Mn can be measured using the universal size exclusion chromatography (SEC) method described in ASTM D6474-12 as follows:

[0115] Chromatography: PolymerChar GPC-IR system running at 160 °C

[0116] Testing: PolymerChar IR5 infrared detector; PolymerChar viscometer

[0117] IR5 is used as a concentration detector.

[0118] Column group: three Polymer Laboratories 13 µm PLgel Olexis, 300 × 7.5 mm

[0119] PE molar mass calibration was performed using linear PE standards (narrow and wide (Mw / Mn = 4 to 15)) in the range of 0.5–2800 kg / mol.

[0120] The concentration of the injected sample was 0.03% m / m, and it was stabilized with Irgafos 168 and Topanol CA (weight ratio of sample:Irgafos:Topanol = 1:1:1).

[0121] The solvent and eluent are 1,2,4-trichlorobenzene stabilized with 1 g / L BHT.

[0122] Polyolefin-based elastomers

[0123] The polymer composition according to the invention comprises a polyolefin-based elastomer. Preferably, the amount of the polyolefin-based elastomer is 3.0 to 20% by weight, for example, 3.0 to 9.0% by weight or 9.0 to 20% by weight, based on the total amount of the polymer composition.

[0124] The polyolefin-based elastomer is preferably an ethylene-α-olefin copolymer, wherein the α-olefin has 3 to 20 carbon atoms. For example, the ethylene-α-olefin copolymer is an ethylene-propylene copolymer, the ethylene-α-olefin copolymer is an ethylene-butene copolymer, the ethylene-α-olefin copolymer is an ethylene-hexene copolymer, the ethylene-α-olefin copolymer is an ethylene-octene copolymer, or a combination thereof.

[0125] Preferably, the polyolefin-based elastomer is an ethylene-butene copolymer or / and an ethylene-octene copolymer.

[0126] Preferably, the amount of the ethylene-derived structural portion in the polyolefin-based elastomer is in the range of 45 to 90% by weight, more preferably in the range of 50 to 87% by weight, more preferably in the range of 55 to 85% by weight, and even more preferably in the range of 57 to 70% by weight, based on the total amount of the polyolefin-based elastomer.

[0127] The polyolefin-based elastomer according to the invention preferably has a Shore A hardness in the range of 40 to 85, more preferably in the range of 51 to 79, and even more preferably in the range of 54 to 68, as measured according to ASTM D2240-15.

[0128] The density of the polyolefin-based elastomer according to the present invention is preferably between 0.853 and 0.905 g / cm³, as measured according to ASTM D792-13. 3 Within the range of 0.859 to 0.896 g / cm³, it is preferred. 3 More preferably, it is within the range of 0.860 to 0.882 g / cm³. 3 More preferably, it is within the range of 0.860 to 0.876 g / cm³. 3 Within the range.

[0129] The MFI of polyolefin-based elastomers is preferably in the range of 0.20 to 20.0 dg / min, more preferably in the range of 0.30 to 14.3 dg / min, and more preferably in the range of 0.40 to 7.2 dg / min, as measured according to ASTM D1238-13 at 190°C with a 2.16 kg load.

[0130] Polyolefin-based elastomers can be prepared using methods known in the art, for example, by using a single-site catalyst, i.e., a catalyst whose transition metal component is an organometallic compound and whose at least one ligand has a cyclopentadienyl anionic structure, through which the ligand is coordinated to the transition metal cation. This type of catalyst is also known as a "metallocene" catalyst. Metallocene catalysts are described, for example, in U.S. Patents 5,017,714 and 5,324,820. Polyolefin-based elastomers can also be prepared using conventional types of multiphase, multisite Ziegler-Natta catalysts.

[0131] Inorganic packing

[0132] The polymer composition according to the invention comprises an inorganic filler. Preferably, the amount of inorganic filler is in the range of 3.0 to 30% by weight, for example, 3.0 to 10% by weight or 10 to 30% by weight, based on the total amount of the polymer composition. Preferably, the ash content of the polymer composition is in the range of 3.0 to 30% by weight, for example, 3.0 to 10% by weight or 10 to 30% by weight, measured according to ISO 3451-1:2008 at 600°C for 4 hours.

[0133] Suitable examples of inorganic fillers include, but are not limited to, talc, calcium carbonate, wollastonite, barium sulfate, kaolin, glass fiber, layered silicates (bentonite, montmorillonite, saponite) and mica.

[0134] For example, inorganic fillers are selected from the group consisting of talc, calcium carbonate, wollastonite, mica and mixtures thereof.

[0135] Preferably, the inorganic filler is talc. According to ISO 13317-3:2001, sedimentary analysis, and Stokes' law, the average particle size (D50) of talc is preferably in the range of 0.12 to 10.2 µm, more preferably in the range of 0.23 to 5.1 µm, and even more preferably in the range of 0.36 to 0.86 µm.

[0136] Preferably, the total amount of the first multiphase propylene copolymer (a), the second multiphase propylene copolymer (b), the high melt strength polypropylene, the polyolefin-based elastomer and inorganic filler, and the optional third multiphase propylene copolymer (c) is at least 95% by weight, preferably at least 97% by weight, and more preferably at least 98.5% by weight, based on the total amount of the polymer composition.

[0137] In some preferred embodiments, the total amount of the first multiphase propylene copolymer (a), the second multiphase propylene copolymer (b), the high melt strength polypropylene, the polyolefin-based elastomer, and the inorganic filler is at least 95% by weight, preferably at least 97% by weight, and more preferably at least 98.5% by weight, based on the total amount of the polymer composition.

[0138] additive

[0139] The polymer compositions according to the invention may further contain additives, such as nucleating and clarifying agents, stabilizers, release agents, plasticizers, antioxidants, lubricants, antistatic agents, crosslinking agents, antiscratch agents, pigments and / or colorants, flame retardants, acid removers, recycling additives, antimicrobial agents, antifogging additives, slip additives, anti-blocking additives, polymer processing aids, etc. Such additives are well known in the art. For polymer compositions with favorable properties, the amount of additive is preferably up to 5.0% by weight, more preferably up to 4.5% by weight, more preferably up to 4% by weight, and more preferably up to 3.8% by weight, based on the total amount of the polymer composition.

[0140] Preferably, the total amount of the first multiphase propylene copolymer (a), the second multiphase propylene copolymer (b), the high melt strength polypropylene, the polyolefin-based elastomer and inorganic filler, and the optional third multiphase propylene copolymer and optional additives is 100 by weight based on the total amount of the polymer composition.

[0141] In some preferred embodiments, the total amount of the first multiphase propylene copolymer (a), the second multiphase propylene copolymer (b), the high melt strength polypropylene, the polyolefin-based elastomer and inorganic filler, and optional additives is 100 by weight based on the total amount of the polymer composition.

[0142] Foamed products

[0143] The present invention further provides a foamed article prepared by foam injection molding of a polymer composition.

[0144] Preferably, the amount of polymer composition relative to the foamed article is at least 90% by weight, at least 95% by weight, at least 98% by weight, at least 99% by weight, or 100% by weight.

[0145] Foamed products can be foamed sheets, having a thickness of, for example, 0.1 to 20 cm, 0.3 to 10 cm, or 0.5 to 5.0 cm. For example, the thickness of the foamed sheet can be 0.1 to 3.0 cm, 3.0 to 10 cm, or 10 to 20 cm.

[0146] Foam Injection Molding

[0147] Generally, to prepare a foamed article, a polymer composition is mixed with a foaming agent. The mixture is then heated to cause the polymer composition to melt and the foaming agent to generate gas. Instead of first providing a mixture of the foaming agent and the polymer composition and then melting it to obtain a molten mixture, a melt of the polymer composition may be provided and the foaming agent incorporated into the melt to obtain a molten mixture. Depending on the method, the resulting mixture remains as a melt carrying the gas until it is distributed in a controlled manner through an orifice or into a forming cavity. When foaming is complete, the foamed article is allowed to solidify by cooling. Such methods are known in the art, for example from Thermoplastic Foams (by James L. Throne, Sherwood Publishers, 1996), which is incorporated herein by reference.

[0148] Preferably, foam injection molding is performed by expanding a molten mixture with a thickness of t0 in a mold to a foamed article with a thickness of t1 at an expansion ratio of t1 / t0 in the range of 1.05 to 2.14, preferably in the range of 1.38 to 1.97, and more preferably in the range of 1.49 to 1.82.

[0149] Preferably, foam injection molding includes the following sequential steps:

[0150] - a) providing a mixture of a foaming agent and a polymer composition and melting the mixture to obtain a molten mixture, or b) providing a melt of a polymer composition and mixing a foaming agent into the melt of the polymer composition to obtain a molten mixture;

[0151] - Inject the molten mixture into a mold;

[0152] - Optionally apply pressure to the molten mixture in the mold;

[0153] - At least partially open the mold to allow the molten mixture to form a soft, foamed article; and

[0154] - Allows soft foamed products to cure to form foamed sheets and removes the foamed sheets from the mold.

[0155] This method is sometimes referred to as the core-back injection molding method or the mold movement method.

[0156] Preferably, the density of the foamed product is 0.50 to 0.80 g / cm³. 3 For example, 0.50 to 0.65 g / cm³ 3 Or 0.65 to 0.80 g / cm³ 3The density was determined according to ISO 845 (2006).

[0157] The foaming agent used according to the present invention can be a physical foaming agent or a chemical foaming agent, wherein the chemical foaming agent is a chemical that decomposes at a specific temperature to release one or more gases, and wherein the physical foaming agent is a volatile liquid or one or more gases. Typical chemical foaming agents include, but are not limited to, azodicarbonamide, sodium bicarbonate, 5-phenyltetrazole, and citrate derivatives.

[0158] Typical physical foaming agents include, but are not limited to, fluids in a gaseous or supercritical state, such as nitrogen, carbon dioxide, hydrocarbons (e.g., butane, pentane), and mixtures thereof.

[0159] The amount of foaming agent used in this invention can vary depending on its properties and foaming performance. In some examples, the amount of foaming agent varies in the range of 0.2-5.0% by weight based on the total weight of the polymer composition.

[0160] The present invention further provides the use of foamed articles according to the invention, or foamed articles obtained or obtainable by the method according to the invention, for the manufacture of automotive parts, such as for the manufacture of automotive exterior or interior parts. Examples include door panels, door trims, dashboards, interior trims, A / B / C pillars, seat upholstery, center consoles, cup holders, armrests, upper / lower dashboard support trims, glove boxes, and tailgate trims (e.g., trunk trim cover, tailgate lower trim frame).

[0161] experiment

[0162] Material

[0163] Polymer A (“Third Multiphase Propylene Copolymer (c)” described above), polymer B (“First Multiphase Propylene Copolymer (a)” described above), and polymer D (“Second Multiphase Propylene Copolymer (b)” described above) are used.

[0164] Polymers A, B, and D are multiphase propylene copolymers prepared using the Innovene™ method, which employs a sequential two-reactor setup. Polypropylene homopolymers are produced in the first reactor, and propylene-ethylene copolymers are produced in the second reactor.

[0165] The catalyst system in the polymerization process consists of three components: a main catalyst, an external electron donor, and a co-catalyst. The main catalyst was prepared according to the description in the "Procatalyst IN" paragraph on page 36 of WO2016198344; the external electron donor for polymers A and B is di(isopropyl)dimethoxysilane (DiPDMS), and the external electron donor for polymer D is n-propyltriethoxysilane (nPTES); the co-catalyst is triethylaluminum. The process conditions for polymers A, B, and D are given in Table 1.

[0166] The method conditions for polymers A, B, and D are given in Table 1:

[0167] Table 1: Preparation conditions of polymers A, B and D

[0168]

[0169] In Table 1, R1 refers to the first reactor, R2 refers to the second reactor, Te refers to temperature, Pr refers to pressure, Al / Ti is the molar ratio of co-catalyst to main catalyst, Si / Ti is the molar ratio of external donor to main catalyst, H2 / C3 is the molar ratio of hydrogen to propylene, C2 / C3 is the molar ratio of ethylene to propylene, and split is the amount of material produced in R1 or R2 based on the total amount of polymer A, B, or D, respectively.

[0170] Engage 8200 is a commercially available ethylene-1-octene elastomer from Dow, with a strength of 0.870 g / cm³. 3 It has a density (ASTM D792-13), an MFI of 5.0 g / 10 min (ASTM D1238-13, 2.16 kg, 190℃), and a Shore A hardness of 66 (ASTM D2240-15).

[0171] Tafmer DF605 is an ethylene-1-butene elastomer commercially available from Mitsui Chemicals, with a strength of 0.861 g / cm³. 3 It has a density (ASTM D792-13), an MFI of 0.5 g / 10 min (ASTM D1238-13, 2.16 kg, 190℃), and a Shore A hardness of 58 (ASTM D2240-15).

[0172] SABIC® PP-UMS 561P is a high melt strength polypropylene with a melt strength exceeding 65 cN.

[0173] Talc HTPultra 5c is an ultrafine talc commercially available from IMI FABI. Based on sedimentary analysis and measurements according to Stokes' Law (ISO 13317-3:2001), the average particle size (D50) of talc in Talc HTPultra 5c is 0.65 µm.

[0174] The additive package used consists of 70% by weight of color masterbatch, 20% by weight of heat and processing stabilizer, and 10% by weight of processing aid, based on the total amount of the additive package.

[0175] The chemical foaming agent used in this invention is ORGATER BA.M2.E, which is commercially available from ADEKA.

[0176] Sample preparation

[0177] Mixing

[0178] The pellets in the example were prepared by compounding the components indicated in Table 3 in the following amounts in a KraussMaffei Berstorff ZE40AJJTX43D twin-screw extruder with the following settings: a screw speed of 400 rpm, a throughput of 150 kg / h, 38% torque, a temperature of 235°C, and a die pressure of 13 bar.

[0179] Foam Injection Molding

[0180] Foamed products are prepared by core-receding foam injection molding. This core-receding foam injection molding method consists of the following sequential steps:

[0181] - The granules obtained in the compounding step of the embodiment are dry-blended with a chemical foaming agent to produce a granule mixture. The amount of chemical foaming agent used is 4% by weight based on the total amount of granules.

[0182] The granular mixture obtained in the dry blending step is then added to the hopper of the injection molding machine. The injection molding machine used is configured with a barrel temperature of 240°C and a mold temperature of 75°C. The mold tooling used comprises a fixed half-mold and a movable half-mold. When the two half-molds are closed, the tooling has a cavity with a rectangular plate geometry of 90 mm wide × 160 mm long.

[0183] - Then the molten mixture of granules (melt) is poured at 250 cm... 3 The injection is carried out at an injection speed of / s and with an injection step duration of 0.2 s;

[0184] - The injected melt is held in the mold at a pressure of 400 bar for 6.5 s, and then the mold is opened within 1 s with a core retraction distance of 1 mm, so that the injected melt expands from an initial (cavity) thickness t0 of 2 mm to a final foam thickness t1 of 3 mm to become foam. The expansion ratio (t1 / t0) is thus 1.5.

[0185] - Allow the foam to cool further in the mold to solidify for 40 seconds, and then remove it from the mold for characterization.

[0186] Test methods

[0187] Melt Flow Index

[0188] Melt flow index (MFI) is measured at 230°C with a 2.16 kg load according to ISO 1133-1:2011.

[0189] Weight percentage of xylene soluble fraction (CXS) and weight percentage of xylene insoluble fraction (CXI).

[0190] The weight percentage of the xylene-soluble portion (CXS) of the multiphase propylene copolymer was determined according to ISO 16152:2005. The weight percentage of the xylene-insoluble portion (CXI) of the multiphase propylene copolymer was calculated using the following equation:

[0191] CXI = 100% by weight - CXS

[0192] The xylene-soluble and xylene-insoluble fractions (CXS and CXI) obtained in this test were used in the intrinsic viscosity (IV) test.

[0193] Intrinsic viscosity (IV)

[0194] The intrinsic viscosity (IV) of CXS and CXI was determined in naphthalene at 135 °C according to ISO 1628-1:2009 and ISO 1628-3:2010, respectively.

[0195] Flexibility

[0196] The flexural properties of the foamed product were measured at 23°C after 7 days according to ISO 14125:1998.

[0197] Puncture impact behavior

[0198] The puncture impact behavior of the foamed product was determined by instrumental impact testing according to ISO 6603-A2 at an impact velocity of 4.4 m / s for 7 days at 23°C and for 7 days at -10°C. The inner diameter of the specimen support ring was 40 mm, and the hemispherical striker used had a diameter of 20 mm.

[0199] ISO 6603-2 curve type assessment is a common method for characterizing force / deflection data obtained through impact testing experiments. It provides four typical curve development types that can usually be observed during data assessment. Generally, these range from ductile to brittle and focus on information such as yielding, crack initiation, and crack propagation. The obtained data has been categorized into these four types, which are summarized below:

[0200] Fracture type:

[0201] YD: Yielding followed by deep stretching (ductility) – optimal choice

[0202] YS: Yielding followed by stable cracking (semi-ductile) – preferred

[0203] YU: Yielding followed by unstable cracking (semi-brittle) – least desirable

[0204] NY: No yield (brittle) – Not preferred

[0205] When the fracture type is the same, the energy at 90% F-max can be used to determine the level of puncture impact behavior. The maximum force (F-max) is determined by the force / deflection response measured from the instrument. The energy at 90% F-max is determined by electronically integrating the force / deflection data until the deflection corresponding to the force having decreased to 90% of F-max after reaching its maximum value.

[0206] Ash content

[0207] The ash content of the polymer composition pellets obtained by the compounding method was measured at 600°C for 4 hours according to ISO 3451-1:2008.

[0208] Surface quality assessment

[0209] Visually inspect the foamed injection-molded product for surface defects on both sides. Evaluate the surface quality on a scale of 1 to 3, with 3 being the best.

[0210]

[0211] result

[0212] Table 2 Properties of HECO

[0213]

[0214] Table 3 Composition and properties of polymer compositions

[0215]

[0216] The comparison between CE-1 to CE-5 and IE-1 to IE-5 is understandable, as the addition of high melt strength polypropylene results in better puncture impact behavior (improved fracture type, or, for the same fracture type, higher energy at 90% F-max) and comparable flexural properties. Surface quality is also maintained.

[0217] IE-1, prepared using the first multiphase propylene copolymer (a) (polymer B), exhibits a particularly large improvement in puncture impact behavior. IE-3, prepared using both the first multiphase propylene copolymer (a) (polymer B) and the second multiphase propylene copolymer (b) (polymer D), exhibits unexpectedly good surface quality.

Claims

1. A composition comprising: i) the first multiphase propylene copolymer (a) and / or the second multiphase propylene copolymer (b), ii) High melt strength polypropylene, iii) Polyolefin-based elastomers, and iv) Inorganic fillers, The first multiphase propylene copolymer (a) has the following characteristics: According to ISO 1133-1:2011, the melt flow index (MFI) is determined at 230°C with a 2.16 kg load in the range of at least 5.6 dg / min and less than 50.0 dg / min. The xylene-soluble fraction, measured according to ISO 16152:2005, is in the range of 18.1 to 27.6% by weight based on the total amount of the first multiphase propylene copolymer (a), wherein: The xylene-soluble portion of the first multiphase propylene copolymer (a) has an intrinsic viscosity in the range of 2.9 to 4.8 dl / g, measured at 135 °C in naphthalene according to ISO 1628-1:2009. The second multiphase propylene copolymer (b) has the following characteristics: According to ISO 1133-1:2011, the melt flow index (MFI) is determined at 230°C with a load of 2.16 kg in the range of 50.0 to 100 dg / min. The xylene-soluble fraction, measured according to ISO 16152:2005, is in the range of 12.1 to 20.6% by weight based on the total amount of the second multiphase propylene copolymer (b), wherein: The xylene-soluble portion of the second multiphase propylene copolymer (b) has an intrinsic viscosity in the range of 3.6 to 6.2 dl / g, measured at 135 °C in naphthalene according to ISO 1628-1:2009.

2. The composition according to any one of the preceding claims, wherein: According to ISO 1133-1:2011, the MFI of the first multiphase propylene copolymer (a) was determined at 230°C with a 2.16 kg load in the range of 8.6 to 45.1 dg / min, preferably in the range of 11.2 to 25.3 dg / min, more preferably in the range of 12.3 to 18.2 dg / min, and / or As determined by ISO 16152:2005, the xylene-soluble portion of the first multiphase propylene copolymer (a) is in the range of 20.3 to 24.2% by weight, based on the total amount of the first multiphase propylene copolymer (a), and / or According to ISO 1628-1:2009, measured at 135°C in naphthalene, the intrinsic viscosity of the xylene-soluble portion of the first multiphase propylene copolymer (a) is in the range of at least 3.3 and less than 4.5 dl / g, preferably in the range of 3.8 to 4.3 dl / g, and / or The ratio between the intrinsic viscosity of the xylene-soluble portion of the first multiphase propylene copolymer (a) and the intrinsic viscosity of the xylene-insoluble portion of the first multiphase propylene copolymer is in the range of 2.0 to 3.5, preferably in the range of 2.2 to 3.

0.

3. The polymer composition according to any one of the preceding claims, wherein: According to ISO 1133-1:2011, the MFI of the second multiphase propylene copolymer (b) was determined at 230°C with a 2.16 kg load in the range of 55.0 to 90.0 dg / min, preferably in the range of 60.0 to 83.0 dg / min, and / or As determined by ISO 16152:2005, the xylene-soluble portion of the second multiphase propylene copolymer (b) is in the range of 12.5 to 20.0% by weight, preferably in the range of 13.0 to 18.0% by weight, based on the total amount of the second multiphase propylene copolymer (b), and / or According to ISO 1628-1:2009, measured at 135°C in naphthalene, the intrinsic viscosity of the xylene-soluble fraction of the second multiphase propylene copolymer (a) is in the range of 4.5 to 5.8 dl / g, and / or The ratio between the intrinsic viscosity of the xylene-soluble portion of the first multiphase propylene copolymer (a) and the intrinsic viscosity of the xylene-insoluble portion of the first multiphase propylene copolymer is in the range of 3.1 to 7.2, preferably in the range of 3.2 to 5.

1.

4. The polymer composition according to any one of the preceding claims, wherein the high melt strength polypropylene has a cylindrical capillary having a length of 20 mm and a width of 2 mm, an initial velocity v0 of 9.8 mm / s, and a melting point of 6 mm / s at a temperature of 200°C according to ISO 16790:2005. 2 The melt strength of the polypropylene measured by acceleration is ≥ 30 cN, preferably ≥ 40 cN, more preferably ≥ 45 cN, even more preferably ≥ 50 cN, even more preferably ≥ 55 cN, even more preferably ≥ 60 cN, and most preferably ≥ 65 cN, and / or the melt strength of the high melt strength polypropylene is ≤ 100 cN, for example ≤ 95 cN, for example ≤ 90 cN, for example ≤ 87 cN, and / or The high melt strength polypropylene has a branching index g' of less than 1.00, where g' = [IV]. br / [IV] lin Where g' is the branching index, [IV br [IV] is the intrinsic viscosity of branched polypropylene. lin It is the intrinsic viscosity of linear polypropylene having the same weight-average molecular weight (within ±10%) as the branched polypropylene.

5. The polymer composition according to any one of the preceding claims, wherein the high melt strength polypropylene has a molecular weight distribution Mw / Mn of 5 to 20, preferably 7 to 17, most preferably 10 to 15 as measured by universal size exclusion chromatography as described in ASTM D6474-12.

6. The polymer composition according to any one of the preceding claims, wherein the polyolefin-based elastomer is an ethylene-α-olefin copolymer, preferably wherein the α-olefin has 3 to 20 carbon atoms, for example, the ethylene-α-olefin copolymer is an ethylene-propylene copolymer, an ethylene-butene copolymer, an ethylene-hexene copolymer, an ethylene-octene copolymer, or a combination thereof.

7. The polymer composition according to any one of the preceding claims, wherein the inorganic filler is talc.

8. The polymer composition according to any one of the preceding claims, wherein the inorganic filler has an average particle size (D50) in the range of 0.12 to 10.2 µm, preferably in the range of 0.23 to 5.1 µm, and more preferably in the range of 0.36 to 0.86 µm, as measured according to ISO 13317-3:2001, deposition analysis, and Stokes' law.

9. The composition according to any one of the preceding claims, wherein: The total amount of the first multiphase propylene copolymer (a) and the second multiphase propylene copolymer (b) is in the range of 30 to 80% by weight, based on the total amount of the polymer composition. The amount of the high melt strength polypropylene is 1.0 to 10% by weight based on the total amount of the polymer composition. The amount of the polyolefin-based elastomer is 3.0% to 20% by weight based on the total amount of the polymer composition. The amount of the inorganic filler is in the range of 3.0 to 30% by weight based on the total amount of the polymer composition, and / or the ash content of the polymer composition, measured according to ISO 3451-1:2008 at 600°C for 4 hours, is in the range of 3.0 to 30% by weight based on the total amount of the polymer composition.

10. The composition according to any one of the preceding claims, wherein the weight ratio between the first multiphase propylene copolymer (a) and the second multiphase propylene copolymer (b) is 1:10 to 10:1, for example, 1:10 to 1:1 or 1:1 to 10:

1.

11. The polymer composition according to any one of the preceding claims, wherein the composition optionally further comprises a third multiphase propylene copolymer, wherein the total amount of the first multiphase propylene copolymer (a), the second multiphase propylene copolymer (b), the high melt strength polypropylene, the polyolefin-based elastomer, the inorganic filler, and the optional third multiphase propylene copolymer is at least 95% by weight, preferably at least 97% by weight, and preferably at least 98.5% by weight, based on the total amount of the polymer composition.

12. A foamed article prepared by foam injection molding of a polymer composition according to any one of the preceding claims.

13. The foamed article according to any one of the preceding claims, wherein the foam injection molding is performed by expanding a molten mixture having a thickness of t0 in a mold to a foamed article having a thickness of t1 with an expansion ratio of t1 / t0 in the range of 1.05 to 2.14, preferably in the range of 1.38 to 1.97, more preferably in the range of 1.49 to 1.

82.

14. A method for preparing foamed articles, the method comprising the following sequential steps: - A mixture of a foaming agent and a polymer composition according to any one of claims 1 to 11; - a) providing a mixture of a foaming agent and the polymer composition and melting the mixture to obtain a molten mixture, or b) providing a melt of the polymer composition and mixing a foaming agent into the melt of the polymer composition to obtain a molten mixture; - Inject the molten mixture into a mold; - Optionally apply pressure to the molten mixture in the mold; - At least partially open the mold to allow the molten mixture to form a soft, foamed article; and - Allow the soft foamed article to solidify to form the foamed article, and remove the foamed article from the mold.

15. Use of the foamed article according to claim 12 or 13, or the foamed article obtained or obtainable by the method according to claim 14, for the manufacture of automotive parts, such as for the manufacture of automotive exterior parts or automotive interior parts.

Images