EPDM-containing polyolefin compositions with improved surface properties in injection molding

Abstract

A polyolefin composition (PC) comprising: i) 50.0 to 70.0 wt% of a first polypropylene (PP1) with an MFR2 of 5.0 to 120 g / 10 min; ii) 5.0 to 20.0 wt% of a first elastomeric ethylene copolymer (EC1) with an MFR2 of 0.2 to 15 g / 10 min; iii) 5.0 to 15.0 wt% of an ethylene-propylene-diene monomer rubber masterbatch composition (MB); iv) 5.0 to 25.0 wt% of a filler (F); and v) optional The additive (A) comprises 0.1 to 5.0% by weight, wherein the ethylene-propylene-diene monomer rubber masterbatch composition (MB) comprises: a) 40.0 to 60.0% by weight of ethylene-propylene-diene monomer rubber (EPDM); b) 15.0 to 50.0% by weight of a second polypropylene (PP2) with an MFR2 of 0.2 to 50 g / 10 min; and c) 2.0 to 29.0% by weight of a second elastomeric ethylene copolymer (EC2) with an MFR2 of 0.2 to 20 g / 10 min.

Description

Technical Field

[0001] The present invention relates to a polyolefin composition (PC) comprising a specific ethylene-propylene diene monomer rubber masterbatch composition (MB), a method for producing said polyolefin composition (PC), and an injection molded article comprising said polyolefin composition (PC). Background Technology

[0002] Achieving a balance of mechanical properties remains one of the key objectives in providing propylene polymer compositions, whether by introducing new polymers or by compounding two or more different polymers. In particular, the balance between stiffness (e.g., flexural modulus and / or tensile modulus) and impact strength (e.g., simply supported beam NIS or cantilever beam NIS) is crucial in most polymer-containing articles, as factors that tend to improve stiffness generally lead to a decrease in impact strength, and vice versa.

[0003] A well-known strategy for achieving a beneficial balance of properties is to add so-called impact modifiers to polypropylene compositions that already possess good stiffness properties. These impact modifiers are typically elastomeric ethylene copolymers, which improve impact strength without reducing stiffness to unacceptable levels. While this strategy has been used for decades, several drawbacks remain. Among these drawbacks is that compositions containing more than 5% by weight of elastomeric ethylene copolymers tend to exhibit surface defects during injection molding, especially for large molded parts. One manifestation of these surface defects is the appearance of so-called “tiger stripes” (or “flow marks”), where alternating bright and dark bands are observed on the polymer surface. Assuming these defects are due to slip adhesion or an unstable flow front during mold filling, they negatively impact the quality of the finished product.

[0004] Another major manifestation of surface defects is the appearance of so-called pinhole defects, which are usually formed by microbubbles and / or gel particles, which may be a result of elastomers and / or fillers in the composition.

[0005] The automotive market has a strong demand for polypropylene injection molded products with paint-free and metallic-like surfaces, but the requirements for their surface quality are very stringent, especially regarding visible defects on the glossy-finished surface of the molded products, including tiger stripes and pinholes, which should be controlled to the lowest possible level. The glossy-finished surface of injection molded products is produced by a mold with an inner cavity having a glossy-finished inner surface.

[0006] Some surface defects with a particle size ≥200 μm, such as microbubbles and gel particles, can usually be eliminated by optimizing process parameters during compounding. Some surface defects with a particle size ≤80 μm are invisible and do not affect surface quality. Surface defects with a particle size of 80-200 μm (such as so-called pinholes) are visible and affect surface quality. These should be controlled and limited to acceptable levels. For example, it is required that the count of visual defects (pinholes) on a 150 mm (L) × 100 mm (W) area on the glossy finished surface of the injection molded sheet be less than 10.

[0007] Therefore, there is a market demand for polyolefin compositions with better surface quality, such as reduced tiger stripe formation and pinhole defects, particularly in injection-molded parts with glossy surfaces. Specifically, for an area of ​​150mm × 100mm, a pinhole count of no more than 10 is considered acceptable. Summary of the Invention

[0008] This invention is based on the discovery that adding a masterbatch comprising an elastomeric ethylene copolymer and EPDM rubber, along with a polypropylene matrix, to a PP compound results in the avoidance of tiger stripe formation on the surface of the PP compound, which is suppressed by the presence of EPDM. Furthermore, the resulting polyolefin composition has a low pinhole count, which can be further reduced by carefully adjusting the relative viscosity of the individual components.

[0009] The masterbatch improves the dispersibility of EPDM in polypropylene compositions with added masterbatch and enhances the performance of EPDM in the composition.

[0010] Therefore, in a first aspect, the present invention relates to a polyolefin composition (PC) comprising:

[0011] i) First polypropylene (PP1), whose melt flow rate (MFR2) is in the range of 5.0 to 120 g / 10 min, as determined according to ISO 1133 at 230 °C under a load of 2.16 kg.

[0012] ii) The first elastomer ethylene copolymer (EC1) has a melt flow rate (MFR2) in the range of 0.2 to 15 g / 10 min, as determined according to ISO 1133 at 190 °C under a load of 2.16 kg.

[0013] iii) Ethylene-propylene-diene monomer rubber (or EPDM rubber) masterbatch composition (MB);

[0014] iv) Packing material (F); and

[0015] v) Optional additives (A),

[0016] The ethylene-propylene-diene monomer rubber masterbatch composition (MB) comprises:

[0017] a) 40.0 to 60.0% by weight of ethylene-propylene-diene monomer rubber (EPDM) relative to the total weight of the ethylene-propylene-diene monomer rubber masterbatch composition (MB);

[0018] b) 15.0 to 50.0% by weight of a second polypropylene (PP2) relative to the total weight of the ethylene-propylene-diene monomer rubber masterbatch composition (MB), having a melt flow rate (MFR2) in the range of 0.2 to 50 g / 10 min, determined according to ISO 1133 at 230°C under a load of 2.16 kg; and

[0019] c) 2.0 to 29.0% by weight of a second elastomeric ethylene copolymer (EC2) relative to the total weight of the ethylene-propylene-diene monomer rubber masterbatch composition (MB), having a melt flow rate (MFR2) in the range of 0.2 to 20 g / 10 min, determined according to ISO 1133 at 190°C under a load of 2.16 kg.

[0020] The total content of each of the ethylene-propylene-diene monomer rubber (EPDM), the second polypropylene (PP2), and the second elastomer ethylene copolymer (EC2) relative to the total weight of the ethylene-propylene-diene monomer rubber masterbatch composition (MB) is at least 90% by weight, more preferably at least 95% by weight, even more preferably at least 98% by weight, and most preferably 100% by weight.

[0021] In another aspect, the present invention relates to a method for producing a polyolefin composition (PC) according to the first aspect, comprising the following steps:

[0022] a) Provides a first polypropylene (PP1), a first elastomer ethylene copolymer (EC1), an ethylene-propylene-diene monomer masterbatch composition (MB), a filler (F), and optional additives (A);

[0023] b) The first polypropylene (PP1), the first elastomer ethylene copolymer (EC1), the ethylene-propylene-diene monomer masterbatch composition (MB), the filler (F), and the optional additive (A) are blended and extruded in an extruder, preferably a twin-screw extruder, at a temperature in the range of 120 to 250°C to produce a polyolefin composition, preferably in granular form.

[0024] In a final aspect, the present invention relates to injection molded articles comprising at least 90% by weight, more preferably at least 95% by weight, and even more preferably at least 98% by weight of a polyolefin composition (PC) of the first aspect, more preferably an injection molded article with a glossy surface.

[0025] definition

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. While any methods and materials similar to or equivalent to those described herein may be used in practice to test the invention, preferred materials and methods are described herein. In describing and claiming protection for this invention, the following terms will be used in accordance with the definitions listed below.

[0027] Unless otherwise expressly stated, the terms “a”, “an”, etc., are used to refer to one or more.

[0028] In the following text, unless otherwise stated, quantities are given in weight % (wt%).

[0029] Propylene homopolymers are polymers that consist essentially of propylene monomer units. Due to impurities, particularly during commercial polymerization, propylene homopolymers may contain up to 0.1 mol% of comonomer units, preferably up to 0.05 mol% of comonomer units, and most preferably up to 0.01 mol% of comonomer units.

[0030] Propylene copolymers are copolymers of propylene monomer units and comonomer units, preferably selected from ethylene and C4-C8 α-olefins. Propylene random copolymers are propylene copolymers in which comonomer units are randomly distributed along the polymer chain, while propylene block copolymers comprise blocks of propylene monomer units and blocks of comonomer units. Propylene random copolymers may contain comonomer units from one or more comonomers with different carbon atomic masses.

[0031] Multiphase propylene copolymers typically contain:

[0032] a) Crystalline propylene homopolymer or copolymer matrix (M); and

[0033] b) Elastomer rubber, preferably propylene-ethylene copolymer (E);

[0034] The invention will now be described in more detail. Detailed Implementation

[0035] First polypropylene (PP1)

[0036] The main component of the polyolefin composition (PC) is polypropylene (PP1).

[0037] The first polypropylene (PP1) of the polyolefin composition (PC) can be a first propylene homopolymer or a first propylene copolymer, more preferably a first propylene copolymer. The first propylene copolymer is preferably a first propylene-ethylene copolymer. The first propylene copolymer can be a first propylene random copolymer or a first propylene block copolymer, more preferably a first propylene block copolymer.

[0038] In a preferred embodiment, the first propylene block copolymer is a first multiphase propylene copolymer (HECO1), or even more preferably a first multiphase propylene-ethylene copolymer.

[0039] The first multiphase propylene copolymer (HECO1), and more preferably the first multiphase propylene-ethylene copolymer, comprises:

[0040] c) Crystalline propylene homopolymer matrix (M); and

[0041] d) Elastomer propylene-ethylene copolymer (E);

[0042] The first propylene copolymer, preferably the first propylene block copolymer, and more preferably the first multiphase propylene copolymer (HECO1) of the polyolefin composition (PC) comprises a comonomer selected from the group consisting of ethylene and α-olefins containing 4 to 12 carbon atoms, more preferably from the group consisting of ethylene, butene, hexene, and octene, and even more preferably selected from ethylene or butene, with ethylene being the most preferred. Particularly preferably, the only comonomer present is ethylene.

[0043] The melt flow rate (MFR2) of the first polypropylene (PP1), more preferably propylene copolymer, even more preferably first propylene block copolymer, still more preferably first multiphase propylene copolymer (HECO1), and even more preferably first multiphase propylene-ethylene copolymer, as measured according to ISO 1133 at 230°C and 2.16 kg, is in the range of 5.0 to 120 g / 10 min, more preferably in the range of 8.0 to 115 g / 10 min, and most preferably in the range of 10.0 to 100 g / 10 min.

[0044] If the first polypropylene (PP1) is a first propylene copolymer, then the comonomer content, more preferably the ethylene (C2) content, is preferably in the range of 2.0 to 30.0% by weight, more preferably in the range of 3.0 to 25.0% by weight, and most preferably in the range of 5.0 to 20.0% by weight, relative to the total weight of the first propylene copolymer.

[0045] Preferably, the xylene cold solubles (XCS) content of the first multiphase propylene copolymer (HECO1), more preferably the first multiphase propylene-ethylene copolymer, is in the range of 5 to 50% by weight, more preferably in the range of 10 to 45% by weight, and most preferably in the range of 12 to 40% by weight.

[0046] Preferably, the total monomer content of the first multiphase propylene copolymer (HECO1), more preferably the total monomer content of the first multiphase propylene-ethylene copolymer, and more preferably the total ethylene (C2) content are in the range of 2.0 to 30.0% by weight, more preferably in the range of 3.0 to 25.0% by weight, and most preferably in the range of 5.0 to 20.0% by weight.

[0047] Preferably, the content of comonomers in the xylene cold soluble fraction of the first multiphase propylene copolymer (HECO1), more preferably in the range of 20 to 45% by weight, and most preferably in the range of 30 to 40% by weight, of the xylene cold soluble fraction of the first multiphase propylene-ethylene copolymer.

[0048] Preferably, the intrinsic viscosity (IV(XCS)) of the xylene cold soluble fraction of the first multiphase propylene copolymer (HECO1), more preferably the first multiphase propylene-ethylene copolymer, is in the range of 1.0 to 4.0 dl / g, more preferably in the range of 1.5 to 3.5 dl / g, and most preferably in the range of 2.0 to 3.0 dl / g.

[0049] Preferably, the melt flow rate (MFR2) of the crystalline propylene homopolymer matrix (M) of the first multiphase propylene copolymer (HECO1), more preferably the first multiphase propylene-ethylene copolymer, measured according to ISO 1133 at 230°C and 2.16 kg, is in the range of 10 to 220 g / 10 min, more preferably in the range of 20 to 210 g / 10 min, and most preferably in the range of 30 to 200 g / 10 min.

[0050] The first polypropylene (PP1), more preferably the first propylene copolymer, even more preferably the first propylene block copolymer, still more preferably the first multiphase propylene copolymer (HECO1), and even more preferably the first multiphase propylene-ethylene copolymer preferably contains a polymer nucleating agent.

[0051] Preferred examples of such polymer nucleating agents are vinyl polymers, such as vinyl polymers derived from monomers of the following formula.

[0052] H2C = CH-CHR 1 R 2

[0053] Where R 1 and R 2Together with the carbon atoms to which they are attached, they form optionally substituted saturated or unsaturated or aromatic ring or fused ring systems, wherein the ring or fused ring portion contains 4 to 20 carbon atoms, preferably 5 to 12 membered saturated or unsaturated or aromatic ring or fused ring systems, or independently represent straight-chain or branched C4-C30 alkanes, C4-C20 cycloalkanes, or C4-C20 aromatic rings. Preferably, R 1 and R 2 Together with the C atoms to which they are attached, they form five- or six-membered saturated or unsaturated or aromatic rings, or independently represent lower alkyl groups containing 1 to 4 carbon atoms. Preferred vinyl compounds for preparing the polymer nucleating agents used according to the invention are, in particular, vinylcycloalkanes, especially vinylcyclohexane (VCH), vinylcyclopentane, and vinyl-2-methylcyclohexane, 3-methyl-1-butene, 3-ethyl-1-hexene, 3-methyl-1-pentene, 4-methyl-1-pentene, or mixtures thereof. Particularly preferably, the vinyl polymer is a vinylcycloalkane polymer, preferably selected from vinylcyclohexane (VCH), vinylcyclopentane, and vinyl-2-methylcyclohexane, wherein a vinylcyclohexane polymer is a particularly preferred embodiment.

[0054] More preferably, the vinyl polymer of the polymer nucleating agent is a homopolymer, and most preferably a vinylcyclohexane homopolymer.

[0055] The first polypropylene (PP1), more preferably the first propylene copolymer, even more preferably the first propylene block copolymer, still more preferably the first multiphase propylene copolymer (HECO1), and even more preferably the first multiphase propylene-ethylene copolymer of the present invention can be synthesized or selected from commercially available polypropylene.

[0056] The first polypropylene (PP1), more preferably the first propylene copolymer, even more preferably the first propylene block copolymer, still more preferably the first multiphase propylene copolymer (HECO1), and even more preferably the first multiphase propylene-ethylene copolymer of the present invention are preferably produced by a sequential multi-stage polymerization process in the presence of a Ziegler-Natta catalyst.

[0057] The preferred multi-stage process is the "loop gas phase" process, such as the one developed by Borealis A / S of Denmark (called...). (Technology), which is described in, for example, patent documents such as EP 0 887 379, WO 92 / 12182, WO 2004 / 000899, WO 2004 / 111095, WO 99 / 24478, WO 99 / 24479 or WO 00 / 68315.

[0058] Another suitable slurry-gas phase process is Basell's The process, which is described in Figure 20 of, for example, the paper by Galli and Vecello, Prog. Polym. Sci. 26 (2001) 1287-1336.

[0059] First elastomer ethylene copolymer (EC1)

[0060] Another essential component of the polyolefin composition (PC) is the first elastomer ethylene copolymer (EC1).

[0061] The melt flow rate (MFR2) of the first elastomer ethylene copolymer (EC1), measured according to ISO 1133 at 190°C and 2.16 kg, is in the range of 0.2 to 15 g / 10 min, more preferably in the range of 0.3 to 10 g / 10 min, and most preferably in the range of 0.5 to 7.0 g / 10 min.

[0062] Preferably, the density of the first elastomer, the ethylene copolymer (EC1), as measured according to ISO 1183-187, is between 860 and 880 g / cm³. 3 Within the range of 865 to 875 g / cm³, it is preferred. 3 Within the range, the optimal value is between 867 and 871 g / cm³. 3 Within the range.

[0063] Preferably, the melting temperature of the first elastomer ethylene copolymer (EC1), as measured according to ISO 11357, is in the range of 30 to 120°C, more preferably in the range of 50 to 100°C, and most preferably in the range of 60 to 80°C.

[0064] Preferably, the first elastomer ethylene copolymer (EC1) is a copolymer of ethylene and one or more comonomers selected from C5 to C12 α-olefins, more preferably selected from C6 to C10 α-olefins, and most preferably the first elastomer ethylene copolymer (EC1) is an ethylene-octene copolymer or an ethylene-hexene copolymer.

[0065] Based on the total weight of the first elastomeric ethylene copolymer (EC1), the comonomer content of the first elastomeric ethylene copolymer (EC1) is preferably in the range of 10 to 65% by weight, more preferably in the range of 20 to 60% by weight, and most preferably in the range of 30 to 50% by weight.

[0066] Ethylene-propylene-diene monomer rubber masterbatch composition (MB)

[0067] Another essential component of the polyolefin composition (PC) is the ethylene-propylene-diene monomer rubber masterbatch composition (MB).

[0068] The ethylene-propylene-diene monomer rubber masterbatch composition (MB) comprises ethylene-propylene-diene monomer rubber (EPDM), a second polypropylene (PP2), and a second elastomer ethylene copolymer (EC2), the properties of which are discussed below.

[0069] The ethylene-propylene-diene monomer rubber masterbatch composition (MB) comprises, more preferably, the following:

[0070] a) 40.0 to 60.0% by weight of ethylene-propylene-diene monomer rubber (EPDM) relative to the total weight of the ethylene-propylene-diene monomer rubber masterbatch composition (MB);

[0071] b) 15.0 to 50.0% by weight of second polypropylene (PP2) relative to the total weight of the ethylene-propylene-diene monomer rubber masterbatch composition (MB);

[0072] c) 2.0 to 29.0% by weight of a second elastomeric ethylene copolymer (EC2) relative to the total weight of the ethylene-propylene-diene monomer rubber masterbatch composition (MB); and

[0073] d) Optionally, 0.1 to 5.0% by weight of additive relative to the total weight of the ethylene-propylene-diene monomer rubber masterbatch composition (MB).

[0074] In a preferred embodiment, the ethylene-propylene-diene monomer rubber masterbatch composition (MB) comprises, more preferably, the following:

[0075] a) 42.0 to 58.0% by weight of ethylene-propylene-diene monomer rubber (EPDM) relative to the total weight of the ethylene-propylene-diene monomer rubber masterbatch composition (MB);

[0076] b) 18.0 to 40.0% by weight of second polypropylene (PP2) relative to the total weight of the ethylene-propylene-diene monomer rubber masterbatch composition (MB);

[0077] c) 10.0 to 28.0% by weight of a second elastomeric ethylene copolymer (EC2) relative to the total weight of the ethylene-propylene-diene monomer rubber masterbatch composition (MB); and

[0078] d) Optionally, 0.1 to 2.0% by weight of additive relative to the total weight of the ethylene-propylene-diene monomer rubber masterbatch composition (MB).

[0079] In another preferred embodiment, the ethylene-propylene-diene monomer rubber masterbatch composition (MB) comprises, more preferably, the following:

[0080] a) 45.0 to 55.0% by weight of ethylene-propylene-diene monomer rubber (EPDM) relative to the total weight of the ethylene-propylene-diene monomer rubber masterbatch composition (MB);

[0081] b) 20.0 to 30.0% by weight of second polypropylene (PP2) relative to the total weight of the ethylene-propylene-diene monomer rubber masterbatch composition (MB);

[0082] c) 20.0 to 27.0% by weight of a second elastomeric ethylene copolymer (EC2) relative to the total weight of the ethylene-propylene-diene monomer rubber masterbatch composition (MB); and

[0083] d) Optionally, 0.1 to 1.0% by weight of additive relative to the total weight of the ethylene-propylene-diene monomer rubber masterbatch composition (MB).

[0084] The total content of ethylene-propylene-diene monomer rubber (EPDM), second polypropylene (PP2), and second elastomeric ethylene copolymer (EC2) relative to the total weight of the ethylene-propylene-diene monomer rubber masterbatch composition (MB) is at least 90% by weight, more preferably at least 95% by weight, even more preferably at least 98% by weight, and most preferably 100% by weight.

[0085] If present, the additives are preferably selected from pigments, antioxidants, UV stabilizers, anti-scratch agents, release agents, deacidifiers, lubricants, antistatic agents, and mixtures thereof.

[0086] Preferably, the ratio of ethylene-propylene-diene monomer rubber (EPDM) to the second elastomer ethylene copolymer (EC2) in the ethylene-propylene-diene monomer masterbatch composition (MB) is in the range of 1.0:1 to 5.0:1, more preferably in the range of 1.3:1 to 4.0:1, and most preferably in the range of 1.5:1 to 3.0:1.

[0087] Preferably, the melt flow rate (MFR2) of the ethylene-propylene-diene monomer rubber masterbatch composition (MB), measured according to ISO 1133 at 230°C and 2.16 kg, is in the range of 0.05 to 5.0 g / 10 min, more preferably in the range of 0.10 to 3.0 g / 10 min, and most preferably in the range of 0.15 to 1.0 g / 10 min.

[0088] Preferably, the ethylene-propylene-diene monomer rubber masterbatch composition (MB) can be obtained by a method comprising the following steps, and more preferably by a method comprising the following steps:

[0089] a) Provide a second polypropylene (PP2), a second elastomer ethylene copolymer (EC2), and an ethylene-propylene-diene monomer rubber (EPDM);

[0090] b) The second polypropylene (PP2), the second elastomer ethylene copolymer (EC2), and the ethylene-propylene-diene monomer rubber (EPDM) are blended and extruded in an extruder, preferably a twin-screw extruder, at a temperature of 120 to 250°C to produce an ethylene-propylene-diene monomer rubber masterbatch composition (MB), preferably in granular form.

[0091] Specifically, conventional compounding or blending equipment is preferably used, such as a Banbury mixer, a two-roll rubber mill, a Buss co-kneader, or a twin-screw extruder. More preferably, mixing is completed in a co-rotating twin-screw extruder. The polymer material recovered from the extruder is typically in granular form. These granules can then be used as EPDM masterbatch for incorporating EPDM into other polypropylene compositions, particularly those for forming molded articles.

[0092] Ethylene-propylene-diene monomer rubber (EPDM)

[0093] The main component of the masterbatch composition is ethylene-propylene-diene monomer rubber (EPDM).

[0094] Preferably, ethylene-propylene-diene monomer rubber (EPDM) is a terpolymer of ethylene, propylene and ethylene norbornene (ENB).

[0095] Preferably, the Mooney viscosity M, measured at 125°C according to ASTM D1646, is a terpolymer of ethylene-propylene-diene monomer rubber (EPDM), more preferably an ethylene, propylene, and ethylene norbornene (ENB). L (1+4) In the range of 40 to 100 MU, preferably in the range of 60 to 95 MU, and most preferably in the range of 75 to 90 MU.

[0096] Preferably, the ethylene-propylene-diene monomer rubber (EPDM), more preferably the terpolymer of ethylene, propylene and ethylene norbornene (ENB) has an ethylene content (C2) in the range of 50 to 90% by weight, more preferably in the range of 55 to 85% by weight, and most preferably in the range of 60 to 80% by weight.

[0097] Preferably, the diene content of the ethylene-propylene-diene monomer rubber (EPDM), more preferably the terpolymer of ethylene, propylene and ethylene norbornene (ENB), and more preferably the ethylene norbornene content (ENB) is in the range of 1.0 to 10.0%, more preferably in the range of 2.0 to 8.0%, and most preferably in the range of 3.0 to 7.0%.

[0098] Preferably, the ethylene-propylene-diene monomer rubber (EPDM), more preferably a terpolymer of ethylene, propylene, and ethylene norbornene (ENB), has a density of 0.80 to 0.96 g / cm³ as measured according to ISO 1183-187. 3 Within the range of 0.83 to 0.93 g / cm³, it is preferred. 3 Within the range, the optimal value is between 0.86 and 0.90 g / cm³. 3 Within the range.

[0099] The ethylene-propylene-diene monomer rubber (EPDM) of the present invention, more preferably a terpolymer of ethylene, propylene and ethylene norbornene (ENB), can be synthesized or selected from commercially available EPDM rubbers, such as Nordel, which is commercially available from Dow Chemical Company (Shanghai, China). TM IP 4785HM.

[0100] Second polypropylene (PP2)

[0101] Another essential component of the ethylene-propylene-diene monomer rubber masterbatch composition (MB) is the second polypropylene (PP2).

[0102] The second polypropylene (PP2) in the polyolefin composition (PC) can be a second propylene homopolymer or a second propylene copolymer, more preferably a second propylene copolymer. The second propylene copolymer is preferably a second propylene-ethylene copolymer. The second propylene copolymer can be a second propylene random copolymer or a second propylene block copolymer, more preferably a second propylene block copolymer, and most preferably a second multiphase propylene copolymer (HECO2).

[0103] Except for the following ranges of the melt flow rate (MFR2) of the second polypropylene (PP2), other properties of the second polypropylene (PP2) or the second multiphase propylene copolymer, including the choice of comonomer, comonomer / ethylene content, xylene cold solubles (XCS) content, comonomer / ethylene content of the XCS fraction, intrinsic viscosity of the XCS fraction, matrix melt flow rate (MFR2), and all properties relating to optional polymer nucleating agents and preparation methods, are the same as those described above for the first polypropylene (PP1) or the first multiphase propylene copolymer.

[0104] The second multiphase propylene copolymer (HECO2), and more preferably the second multiphase propylene-ethylene copolymer, comprises:

[0105] a) Crystalline propylene homopolymer matrix (M); and

[0106] b) Elastomer propylene-ethylene copolymer (E);

[0107] The melt flow rate (MFR2) of the second polypropylene (PP2), more preferably propylene copolymer, even more preferably second propylene block copolymer, still more preferably second multiphase propylene copolymer (HECO2), and even more preferably second multiphase propylene-ethylene copolymer, as measured according to ISO 1133 at 230°C and 2.16 kg, is in the range of 0.2 to 50 g / 10 min, more preferably in the range of 0.3 to 35 g / 10 min, and most preferably in the range of 0.5 to 30 g / 10 min.

[0108] In the polyolefin composition (PC), the second polypropylene (PP2) may be the same as the first polypropylene (PP1), or the second polypropylene (PP2) may be different from the first polypropylene (PP1). Preferably, the second polypropylene (PP2) has a lower MFR than the first polypropylene (PP1).

[0109] Second elastomer ethylene copolymer (EC2)

[0110] Another essential component of the ethylene-propylene-diene monomer rubber masterbatch composition (MB) is the second elastomer ethylene copolymer (EC2).

[0111] The definitions of density, melting temperature, comonomer selection, and comonomer content for the second elastomeric ethylene copolymer (EC2) are the same as those for the first elastomeric ethylene copolymer (EC1) as described above.

[0112] The melt flow rate (MFR2) of the second elastomer ethylene copolymer (EC2), measured according to ISO 1133 at 190°C and 2.16 kg, is in the range of 0.2 to 20 g / 10 min, more preferably in the range of 0.3 to 15 g / 10 min, and most preferably in the range of 0.5 to 10 g / 10 min.

[0113] In the polyolefin composition (PC), the second elastomeric ethylene copolymer (EC2) may be the same as the first elastomeric ethylene copolymer (EC1), or the second elastomeric ethylene copolymer (EC2) may be different from the first elastomeric ethylene copolymer (EC1). Preferably, the second elastomeric ethylene copolymer (EC2) has a higher MFR2 than the first elastomeric ethylene copolymer (EC1).

[0114] Packing material (F)

[0115] Another essential component of polyolefin compositions (PC) is filler (F).

[0116] Preferably, the filler is an inorganic filler, more preferably selected from the group containing talc, calcium carbonate, barium sulfate, mica and mixtures thereof.

[0117] Most preferably, the inorganic filler (F) is talc.

[0118] Additive (A)

[0119] The polyolefin composition (PC) of the present invention may contain 0.1 to 5.0% by weight of additive (A). Those skilled in the art will be able to select suitable additives well known in the art.

[0120] Additive (A) is preferably selected from pigments, antioxidants, UV stabilizers, anti-scratch agents, release agents, deacidifiers, lubricants, antistatic agents and mixtures thereof.

[0121] It should be understood that the amount of additive (A) given relative to the total weight of the polyolefin composition (PC) includes any carrier polymer used to introduce the additive into the polyolefin composition (PC), i.e., a masterbatch carrier polymer. An example of such a carrier polymer is a polypropylene homopolymer in powder form.

[0122] Polyolefin composition (PC)

[0123] The polyolefin composition (PC) of the present invention comprises a first polypropylene (PP1), a first elastomer ethylene copolymer (EC1), an ethylene-propylene-diene monomer rubber masterbatch composition (MB), a filler (F), and an optional additive (A).

[0124] The contents of the first polypropylene (PP1), the first elastomer ethylene copolymer (EC1), the ethylene-propylene-diene monomer rubber masterbatch composition (MB), the filler (F), and the optional additive (A) are preferably at least 90% by weight, more preferably at least 95% by weight, even more preferably at least 98% by weight, and most preferably 100% by weight, relative to the total weight of the polyolefin composition (PC).

[0125] The polyolefin composition (PC) preferably comprises the following, and more preferably consists of the following:

[0126] i) 50.0 to 70.0% by weight of first polypropylene (PP1) relative to the total weight of the polyolefin composition (PC);

[0127] ii) 5.0 to 20.0% by weight of the first elastomeric ethylene copolymer (EC1) relative to the total weight of the polyolefin composition (PC);

[0128] iii) 5.0 to 15.0% by weight of ethylene-propylene-diene monomer rubber masterbatch composition (MB) relative to the total weight of the polyolefin composition (PC);

[0129] iv) 5.0 to 25.0% by weight of filler (F) relative to the total weight of the polyolefin composition (PC); and

[0130] v) Optionally, 1.0 to 5.0% by weight of additive (A) relative to the total weight of the polyolefin composition (PC).

[0131] In a preferred embodiment, the polyolefin composition (PC) comprises, more preferably, the following:

[0132] i) 55.0 to 67.0% by weight of first polypropylene (PP1) relative to the total weight of the polyolefin composition (PC);

[0133] ii) 7.0 to 17.0% by weight of the first elastomeric ethylene copolymer (EC1) relative to the total weight of the polyolefin composition (PC);

[0134] iii) 7.0 to 13.0% by weight of ethylene-propylene-diene monomer rubber masterbatch composition (MB) relative to the total weight of the polyolefin composition (PC);

[0135] iv) 7.0 to 20.0% by weight of filler (F) relative to the total weight of the polyolefin composition (PC); and

[0136] v) Optionally, 1.0 to 5.0% by weight of additive (A) relative to the total weight of the polyolefin composition (PC).

[0137] In each of these embodiments, the respective contents of the first polypropylene (PP1), the first elastomer ethylene copolymer (EC1), the ethylene-propylene-diene monomer rubber masterbatch composition (MB), the filler (F), and the optional additive (A) are preferably totaled at least 90% by weight, more preferably at least 95% by weight, even more preferably at least 98% by weight, and most preferably 100% by weight, relative to the total weight of the polyolefin composition (PC).

[0138] In another preferred embodiment, the polyolefin composition (PC) comprises, more preferably, the following:

[0139] i) 60.0 to 65.0% by weight of first polypropylene (PP1) relative to the total weight of the polyolefin composition (PC);

[0140] ii) 9.0 to 14.0% by weight of the first elastomeric ethylene copolymer (EC1) relative to the total weight of the polyolefin composition (PC);

[0141] iii) 8.0 to 12.0% by weight of ethylene-propylene-diene monomer rubber masterbatch composition (MB) relative to the total weight of the polyolefin composition (PC);

[0142] iv) 10.0 to 15.0% by weight of filler (F) relative to the total weight of the polyolefin composition (PC); and

[0143] v) Optionally, 1.0 to 5.0% by weight of additive (A) relative to the total weight of the polyolefin composition (PC).

[0144] Preferably, the melt flow rate (MFR2) of the first polypropylene (PP1) measured according to ISO 1133 at 230°C and under a load of 2.16 kg is higher than that of the second polypropylene (PP2) measured according to ISO 1133 at 230°C and under a load of 2.16 kg.

[0145] Furthermore, preferably, the melt flow rate (MFR2) of the first elastomer ethylene copolymer (EC1) measured according to ISO 1133 at 190°C and under a load of 2.16 kg is lower than that of the second elastomer ethylene copolymer (EC2) measured according to ISO 1133 at 190°C and under a load of 2.16 kg.

[0146] Furthermore, preferably, the ratio [η(MB) / η(PP1)] between the viscosity η(MB) of the ethylene-propylene-diene monomer rubber masterbatch composition and the viscosity η(PP1) of the first polypropylene is in the range of 1.00 to 5.00, more preferably in the range of 1.20 to 4.75, and most preferably in the range of 1.50 to 4.50, wherein the viscosity is determined according to ISO 11443 at a temperature of 250°C and 640s. -1 The shear rate was measured at a temperature that was matched to the typical temperature and shear rate of polyolefins in the compounding process in a twin-screw extruder.

[0147] More preferably, the ratio [η(MB) / η(EC1)] between the viscosity η(MB) of the ethylene-propylene-diene monomer rubber masterbatch composition and the viscosity η(EC1) of the first elastomer ethylene copolymer is in the range of 0.10 to 1.50, more preferably in the range of 0.30 to 1.45, and most preferably in the range of 0.50 to 1.25, wherein the viscosity is measured according to ISO 11443 at a temperature of 250°C and 640s. -1 The shear rate was measured.

[0148] A particular finding of this invention is that when any of the viscosity ratios given above is satisfied, the surface quality of the injection-molded article, such as pinholes, is further improved, resulting in excellent results.

[0149] Preferably, the ratio [η(MB) / η(PP1)] between the viscosity η(MB) of the ethylene-propylene-diene monomer rubber masterbatch composition and the viscosity η(PP1) of the first polypropylene is in the range of 1.00 to 5.00, more preferably in the range of 1.20 to 4.85, and most preferably in the range of 1.50 to 4.75, all viscosity values ​​according to ISO 11443 at a temperature in the range of 200 to 300°C and 80 to 1280 seconds. -1 The shear rates were measured within a range that matched the range of shear rates and temperatures of polyolefins during compounding processes in twin-screw or single-screw extruders or injection molding machines.

[0150] Also preferably, the ratio [η(MB) / η(EC1)] between the viscosity η(MB) of the ethylene-propylene-diene monomer rubber masterbatch composition and the viscosity η(EC1) of the first elastomer ethylene copolymer is in the range of 0.10 to 1.50, more preferably in the range of 0.3 to 1.45, and most preferably in the range of 0.50 to 1.25, all viscosity values ​​according to ISO 11443 at a temperature in the range of 200 to 300°C and 80 to 1280 seconds. -1 The shear rate was measured within the specified range.

[0151] A particular finding of this invention is that, when any of the viscosity ratios given above are satisfied (within a temperature range of 200-300°C and 80-1280 s), -1 When the shear rate is within the specified range, the surface quality (e.g., pinholes) of the injection molded product is further improved, resulting in excellent results.

[0152] The melt flow rate (MFR2) of the polyolefin composition (PC), as determined according to ISO 1133 at 230°C and under a load of 2.16 kg, is preferably in the range of 5.0 to 100 g / 10 min, more preferably in the range of 7.0 to 80 g / 10 min, and most preferably in the range of 10.0 to 60 g / 10 min.

[0153] In the EPDM masterbatch, the selection of the second elastomer ethylene copolymer (EC2) and the second polypropylene (PP2) improves the dispersibility of EPDM within the masterbatch, while the masterbatch itself also contributes to the dispersibility of EPDM within the polypropylene composition to which the masterbatch has been added. Therefore, the final polypropylene composition not only exhibits a uniform phase dispersion but also demonstrates improved surface quality due to the introduction of EPDM.

[0154] In addition, the polypropylene compositions of the present invention can be compounded at a lower specific energy input (≤0.20 kWh / kg) than the typical specific energy input (0.25 kWh / kg or higher) used for polypropylene compositions, even if EPDM has been introduced.

[0155] In addition to improved surface quality, the final polypropylene composition also exhibits good mechanical properties acceptable to the end user, including flexural modulus, impact resistance, etc.

[0156] The polyolefin composition (PC) can be obtained by the following methods, more preferably by the following methods.

[0157] Method for producing polyolefin compositions (PC)

[0158] In another aspect, the present invention relates to a method for producing a polyolefin composition (PC) according to the first aspect, comprising the following steps:

[0159] a) Provides a first polypropylene (PP1), a first elastomer ethylene copolymer (EC1), an ethylene-propylene-diene monomer rubber masterbatch composition (MB), a filler (F), and optional additives (A);

[0160] b) The first polypropylene (PP1), the first elastomer ethylene copolymer (EC1), the ethylene-propylene-diene monomer rubber masterbatch composition (MB), the filler (F), and optional additives (A) are blended and extruded in an extruder, preferably a twin-screw extruder, at a temperature in the range of 120 to 250°C to produce a polyolefin composition (PC), preferably in granular form.

[0161] Specifically, conventional compounding or blending equipment is preferred, such as a Banbury internal mixer, a two-roll rubber mill, a Buss co-kneader, or a twin-screw extruder. More preferably, mixing is completed in a co-rotating twin-screw extruder. The polymer material recovered from the extruder is typically in granular form.

[0162] Particularly preferably, the polyolefin composition (PC) of the present invention is used to produce injection-molded articles. Therefore, preferably, the method further includes the following step after step b):

[0163] c) Inject the polyolefin composition (PC) produced in step b) to form an injection-molded article.

[0164] The injection molding is preferably glossy surface injection molding.

[0165] Those skilled in the art will understand that glossy surface injection molding involves the use of highly specialized so-called Class A molds with a high gloss finish, resulting in very smooth injection molded articles. Suitable injection molds are commercially available and are well known in the art.

[0166] Products

[0167] The present invention also relates to injection-molded articles comprising the polyolefin composition (PC) of the present invention.

[0168] Preferably, the injection molded product is a glossy surface injection molded product.

[0169] Injection molded articles, more preferably glossy surface injection molded articles, contain at least 90% by weight, more preferably at least 95% by weight, and even more preferably at least 98% by weight of a polyolefin composition (PC).

[0170] In a particularly preferred embodiment, the injection-molded article, more preferably a glossy surface injection-molded article, is composed of a polyolefin composition (PC).

[0171] Particularly preferred, injection molded articles, more preferably glossy surface injection molded articles, can be obtained by a method having steps a) to c) as described above, and even more preferably by a method having steps a) to c) as described above.

[0172] Preferably, the article is part of an automotive article, especially an exterior automotive component such as a bumper, or an interior component such as an instrumental carrier, dashboard, interior trim, etc.

[0173] Example

[0174] 1. Definition / Measurement Method

[0175] Unless otherwise defined, the following definitions and determination methods apply to the above general description of the invention and the following embodiments.

[0176] Density was measured according to ISO 1183-187. Sample preparation was performed by compression molding according to ISO 1872-2:2007.

[0177] MFR2: Melt Flow Rate (MFR) is determined according to ISO 1133 and expressed in g / 10 min. MFR is an indicator of the polymer's flowability and therefore its processing properties. The higher the melt flow rate, the lower the polymer's viscosity. The MFR2 of polypropylene was determined at a temperature of 230°C and a load of 2.16 kg. The MFR2 of the elastomer ethylene copolymer was determined at a temperature of 190°C and a load of 2.16 kg.

[0178] Melting temperature Tm: Melting temperature is measured according to ISO 11357-3.

[0179] Quantitative analysis of the microstructure of propylene copolymers using NMR spectroscopy

[0180] Quantitative nuclear magnetic resonance (NMR) spectroscopy was used to quantify the comonomer content of propylene polymers.

[0181] Quantitative data were recorded in solution using a Bruker Advance III 400 NMR spectrometer. 13 C{ 1 HNMR spectroscopy, for 1 H and 13 C was operated at 400.15 and 100.62 MHz, respectively. All spectra were performed using... 13 A C-optimized 10mm extended temperature probe was used for recording at 125°C, and nitrogen was used for all pneumatic devices. Approximately 200 mg of material was dissolved together with chromium acetylacetone (III) (Cr(acac)3) in 3 ml of 1,2-tetrachloroethane-d2 (TCE-d2) to form a 65 mM relaxant solution in the solvent, as described in G. Singh, A. Kothari, V. Gupta, Polymer Testing 2009, 28(5), 475.

[0182] To ensure a homogeneous solution, the NMR tube was further heated in a rotary furnace for at least 1 hour after initial sample preparation in the heating block. After insertion into the magnet, the tube was rotated at 10 Hz. This setup was chosen primarily for its high resolution and the precise quantification required for accurate ethylene content. Standard single-pulse excitation was used without NOE, employing an optimized tip angle, a 1-second cycle delay, and a dual-stage WALTZ16 decoupling scheme, as described in Z. Zhou, R. Kuemmerle, X. Qiu, D. Redwine, R. Cong, A. Taha, D. Baugh, B. Winniford, J. Mag. Reson. 187 (2007) 225 and V. Busico, P. Carbonniere, R. Cipullo, C. Pellecchia, J. Severn, G. Talarico, Macromol. Rapid Commun. 2007, 28, 1128. A total of 6144 (6 k) transients were acquired for each spectrum. For quantification... 13 C{ 1 The ¹H NMR spectra were processed, integrated, and the relevant quantitative properties were determined based on the integration. 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 method allows for comparable references even if the structural unit is not present.

[0183] Using the characteristic signals corresponding to the observed 2,1 Erythro type regional defects (as described in L. Resconi, L. Cavallo, A. Fait, F. Piemontesi, Chem. Rev. 2000, 100(4), 1253; Cheng, HN, Macromolecules 1984, 17, 1950; and WJ. Wang and S. Zhu, Macromolecules 2000, 33, 1157), it is necessary to correct for the influence of regional defects on the measured properties. No characteristic signals corresponding to other types of regional defects were observed.

[0184] Observe the characteristic signals corresponding to the incorporation of ethylene (as described in Cheng, HN, Macromolecules 1984, 17, 1950) and calculate the comonomer fraction as the fraction of ethylene in the polymer relative to all monomers in the polymer.

[0185] Using the method described in W.J.Wang and S.Zhu, Macromolecules 2000, 33 1157, by... 13 C{ 1 The comonomer fraction is quantified by integrating multiple signals across the entire spectral region of the H spectrum. This method was chosen because of its robustness and ability to account for regional defects when necessary. The integration region was slightly adjusted to increase applicability across the entire range of comonomer contents encountered.

[0186] The molar percentage of comonomer incorporated is calculated from the mole fraction.

[0187] The weight percentage of comonomer incorporated is calculated from the weight fraction.

[0188] The comonomer content in ethylene elastomer copolymers (EC) and ethylene-propylene-diene monomer rubbers (EPDM) was determined using a Nicolet Magna 550IR spectrometer and Nicolet Omnic FTIR software, based on... 13 Fourier transform infrared spectroscopy (FTIR) calibrated by C-NMR was measured in a known manner. A film with a thickness of approximately 250 μm was press-molded from the sample. Similar films were prepared from calibration samples with known comonomer contents. The comonomer contents ranged from 1430 to 1100 cm⁻¹. -1 The spectroscopic determination involves selecting a so-called short baseline, long baseline, or both, and measuring absorbance as the peak height. The short baseline is approximately 1410–1320 cm⁻¹. -1 The baseline is drawn using the minimum point, with the long baseline ranging from approximately 1410 to 1220 cm. -1The data is plotted between these baselines. Specific calibration is required for each baseline type. Furthermore, the comonomer content of unknown samples must be within the range of the comonomer content of the calibrated samples.

[0189] Xylene-soluble fraction at room temperature (XCS) (XCS, wt%): The amount of polymer soluble in xylene was determined at 25°C according to ISO 16152, first edition, July 1, 2005. The remainder is the xylene-insoluble fraction (XCU).

[0190] Intrinsic viscosity (IV) was measured according to ISO 1628-1 (in decahydronaphthalene at 135°C).

[0191] Mooney viscosity was measured at 125°C according to ASTM D1646.

[0192] Simply supported beam impact test: Notched impact strength (NIS) of simply supported beams according to ISO 179-1eA at +23°C and -20°C, using 80×10×4mm beams prepared according to ISO 1873-2:2007. 3 Measurements were taken from the injection molding rod sample.

[0193] Flexural modulus: Flexural modulus according to ISO 178 at 23°C for injection molded 80×10×4mm according to EN ISO 1873-2. 3 The test bar was measured by bending at three points.

[0194] Viscosity: Viscosity was measured according to ISO 11443:2021 using a Goettfert capillary rheometer "RG25" with capillary head dimensions of d = 1 mm and L = 10 mm.

[0195] Surface quality: pinholes and tiger stripes

[0196] According to ISO 19069-2, injection molded sheets of 150mm × 100mm × 3mm are prepared using an ENGEL AUSTRIAGmbH injection molding machine “Engel 120” and a mold with a glossy finished inner surface of the cavity.

[0197]

[0198] Visually inspect the injection-molded sheet for tiger stripes and pinhole defects with a particle size of 80-200μm, counting them over a 150mm × 100mm area on the sheet surface.

[0199] 2. Example

[0200] 2.1. Synthesis of multiphase propylene-ethylene copolymer (HECO)

[0201] The catalyst used in each polymerization was a Ziegler-Natta catalyst from Borealis with a Ti content of 1.9 wt% (as described in EP 591 224). Prior to polymerization, the catalyst was prepolymerized with vinylcyclohexane (VCH), as described in EP1 028984 and EP 1 183 307. A 1:1 VCH to catalyst ratio was used in the preparation, resulting in a final poly-VCH content of less than 100 ppm.

[0202] In the first stage, the above-mentioned catalyst was fed into the prepolymerization reactor along with propylene and small amounts of hydrogen (2.5 g / h) and ethylene (330 g / h). Triethylaluminum was used as a cocatalyst and dicyclopentyldimethoxysilane was used as a donor. The aluminum-to-donor ratio was 7.5 mol / mol and the aluminum-to-titanium ratio was 300 mol / mol. The reactor was operated at a temperature of 30 °C and a pressure of 55 bar.

[0203] The subsequent polymerization was carried out under the following conditions.

[0204] Table 1: Polymerization conditions of HECO

[0205]

[0206] In addition, the following commercially available polymer grades were used in the following embodiments:

[0207] EPDM ethylene-propylene-ethylidene norbornene terpolymer, its trade name is NORDEL TM IP4785HM, commercially available from Dow Chemical Company (USA), MFR2 (190℃) << 0.2 g / 10 min, Mooney viscosity (ML 1+4, 125℃) 85 MU, ethylene content 68 wt%, ethylene norbornene content 4.9 wt%, propylene content 27.1%, and density 0.88 g / cm³. 3 .

[0208] EC1 elastomer, an ethylene-octene copolymer, traded under the name Fortify C5070D, is available from Sabic (Shanghai) Trading Co., Ltd. (China). It has an MFR2 (190°C) of 5.0 g / 10 min, a Mooney viscosity (ML 1+4, 125°C) of 8 MU, and a density of 0.868 g / cm³. 3 .

[0209] EC2 is an elastomer, an ethylene-octene copolymer, commercially available under the name Engage XLT 8677 from Dow Chemical Company (USA). It has an MFR2 (190°C) of 0.5 g / 10 min, a Mooney viscosity (ML 1+4, 125°C) of 45 MU, and a density of 0.870 g / cm³. 3 .

[0210] EC3 is an elastomer, an ethylene-octene copolymer, commercially available under the brand name Engage 8100 from Dow Chemical Company (USA). It has an MFR2 (190°C) of 1.0 g / 10 min, a Mooney viscosity (ML 1+4, 125°C) of 24 MU, and a density of 0.870 g / cm³. 3 .

[0211] F talc, marketed as HTP Ultra 5L, is available from IMI Fabi (Italy).

[0212] CMB masterbatch, traded under the name KMB-L5305HW, is available from Kestro Polychem, Inc. (China).

[0213] The additive masterbatch, based on 100% of the total weight of the polyolefin composition, consists of the following: 0.8 wt% of a carrier propylene homopolymer, commercially available under the name PP-H 225, from Hongji Petrochemical (China), with an MFR2 (230℃, 2.16kg) of 27 g / 10 min; 0.15 wt% of an antioxidant, commercially available under the name Irganox 1076 (CAS-no. 2082-79-3), from BASF SE (Germany); 0.15 wt% of an antioxidant, commercially available under the name Irgafos 168 (CAS-no. 31570-04-4), from BASF SE (Germany); and 0.15 wt% of glyceryl monostearate (CAS-no. 91052-47-0), commercially available under the name Rikemal AS-005, from Riken Vitamin. Purchased from Co., Ltd. (Japan); 0.30 wt% of UV stabilizer, trade name Cyasorb V703, available from Solvay (China); 0.30 wt% of lubricant, trade name Crodamide VRX, available from Croda (UK); and 0.15 wt% of calcium stearate (CAS-no. 1592-23-0), available from FACI Chemicals (Zhangjiagang) Co., Ltd. (China).

[0214] 2.2. Preparation of Masterbatch Composition

[0215] The masterbatch composition (MB) was prepared by compounding 25% by weight of HECO1, 25% by weight of EC1 and 50% by weight of EPDM in a co-rotating twin-screw extruder "STS35" available from Coperion, with a barrel temperature of 210°C, a die temperature of 212°C, a screw speed of 507 rpm, a production rate of 40.5 kg / h, a torque of 47%, a die pressure of 3.3 bar, and a specific energy input (SEI) of 0.392 kW·h / kg.

[0216] 2.3. Preparation of Compounds in Examples and Comparative Examples

[0217] Based on the formulations indicated in Table 2, inventive examples and comparative examples were prepared by compounding in a co-rotating twin-screw extruder “STS35” from Coperon under the conditions described in Table 3.

[0218] Table 2: Formulations of the Invention Examples and Comparative Examples

[0219]

[0220] Table 3: Blending conditions for comparative and inventive examples in twin-screw extruders

[0221]

[0222] 2.4. Viscosity properties of components and compositions

[0223] The MFR2 (Table 4) and viscosity (η) (Table 5) of each polymer component, as well as the inventive and comparative compositions, were determined, and the viscosity ratios were calculated (Table 6). Viscosities were measured at temperatures ranging from 200 to 300°C and 80 to 1280 s. -1 The measurements were taken at shear rates that reflect the conditions of typical polyolefin blends in extruders or injection molding machines.

[0224] Table 4: Melt flow rates (MFR2) measured at 230℃ and 190℃

[0225]

[0226] Table 5a: 80 to 1280s -1 The shear rate and viscosity (in Pa·s) measured at temperatures ranging from 200 to 300 °C.

[0227]

[0228] Table 5b: From 80 to 1280s -1The shear rate and viscosity (in Pa·s) measured at temperatures ranging from 200 to 300 °C.

[0229]

[0230] Table 6a: Viscosity ratio between EPDM masterbatch and HECO

[0231]

[0232] Table 6b: Viscosity ratio between EPDM masterbatch and EC

[0233]

[0234] 2.5. Injection Molded Products

[0235] According to the injection molding method described in the determination method (under surface quality), injection molded sheets of 150 mm × 100 mm × 3 mm were prepared from the inventive and comparative polyolefin compositions.

[0236] Inspect the injection-molded sheet for pinhole defects and count the pinhole defects on a 150mm × 100mm surface of the sheet. The results are summarized in Table 7.

[0237] According to the injection molding method described in the determination method (under the test of impact strength and flexural modulus of simply supported beams), 80 mm × 10 mm × 4 mm injection molded test bars were prepared from the invented and comparative polyolefin compositions, and their mechanical properties were evaluated. The results are summarized in Table 7.

[0238] Table 7: Surface Properties of Injection Molded Sheets

[0239]

[0240] As can be seen from Table 7, the inventive compositions have a much lower pinhole count than the comparative compositions, and all inventive compositions and comparative compositions have no tiger stripes on the surface due to the presence of EPDM.

[0241] Furthermore, it can be seen that the examples (i.e., IE1 to IE3) with a viscosity ratio [η(MB) / η(PP1)] greater than 5.0 and a viscosity ratio [η(MB) / η(EC1)] of at least 1.50 have a pinhole count exceeding 10 (on a 150mm × 100mm surface). While this is significantly better than the comparative examples, it is certainly desirable to achieve the lowest possible pinhole content. In particular, as mentioned above, a threshold of 10 is generally considered an acceptable threshold for a glossy finish surface of injection-molded articles.

[0242] The viscosity ratio [η(MB) / η(PP1)] of IE4 and IE5 is less than 5.00. Although the other viscosity ratio [η(MB) / η(EC1)] remains at least 1.50, the pinhole count now drops below the threshold of 10 (on a 150mm × 100mm surface).

[0243] The viscosity ratio [η(MB) / η(EC1)] for IE6 and IE7 is less than 1.50. Although the other viscosity ratio [η(MB) / η(PP1)] is still greater than 5.00, the pinhole count now drops below the threshold of 10 (on a 150mm × 100mm surface).

[0244] In addition, as shown in Table 7, the compositions of the present invention have good mechanical properties and are acceptable for injection molded articles.

Claims

1. A polyolefin composition (PC) comprising: i) First polypropylene (PP1), whose melt flow rate (MFR2) is in the range of 5.0 to 120 g / 10 min, as determined according to ISO 1133 at 230 °C under a load of 2.16 kg. ii) The first elastomer ethylene copolymer (EC1) has a melt flow rate (MFR2) in the range of 0.2 to 15 g / 10 min, as determined according to ISO 1133 at 190 °C under a load of 2.16 kg. iii) Ethylene-propylene-diene monomer rubber masterbatch composition (MB); iv) Packing material (F); and v) Optional additive (A), The ethylene-propylene-diene monomer rubber masterbatch composition (MB) comprises: a) 40.0 to 60.0% by weight of ethylene-propylene-diene monomer rubber (EPDM) relative to the total weight of the ethylene-propylene-diene monomer rubber masterbatch composition (MB); b) 15.0 to 50.0% by weight of a second polypropylene (PP2) relative to the total weight of the ethylene-propylene-diene monomer rubber masterbatch composition (MB), having a melt flow rate (MFR2) in the range of 0.2 to 50 g / 10 min, determined according to ISO 1133 at 230°C under a load of 2.16 kg; and c) 2.0 to 29.0% by weight of a second elastomeric ethylene copolymer (EC2) relative to the total weight of the ethylene-propylene-diene monomer rubber masterbatch composition (MB), having a melt flow rate (MFR2) in the range of 0.2 to 20 g / 10 min, determined according to ISO 1133 at 190°C under a load of 2.16 kg. The total content of each of the ethylene-propylene-diene monomer rubber (EPDM), the second polypropylene (PP2), and the second elastomer ethylene copolymer (EC2) relative to the total weight of the ethylene-propylene-diene monomer rubber masterbatch composition (MB) is at least 90 by weight.

2. The polyolefin composition (PC) according to claim 1, wherein the melt flow rate (MFR2) of the first polypropylene (PP1) measured according to ISO 1133 at 230°C and a load of 2.16 kg is higher than that of the second polypropylene (PP2) measured according to ISO 1133 at 230°C and a load of 2.16 kg, and / or The melt flow rate (MFR2) of the first elastomer ethylene copolymer (EC1) measured according to ISO 1133 at 190°C and under a load of 2.16 kg is lower than that of the second elastomer ethylene copolymer (EC2) measured according to ISO 1133 at 190°C and under a load of 2.16 kg.

3. The polyolefin composition (PC) according to claim 1, wherein the ratio [η(MB) / η(PP1)] between the viscosity η(MB) of the ethylene-propylene-diene monomer rubber masterbatch composition and the viscosity η(PP1) of the first polypropylene is in the range of 1.00 to 5.00; and / or The ratio [η(MB) / η(EC1)] between the viscosity η(MB) of the ethylene-propylene-diene monomer rubber masterbatch composition and the viscosity η(EC1) of the first elastomer ethylene copolymer is in the range of 0.10 to 1.

50. Each viscosity is determined according to ISO 11443 at a temperature of 250°C and a time of 640 seconds. -1 The shear rate was measured.

4. The polyolefin composition (PC) according to any one of claims 1 to 3, wherein the polyolefin composition (PC) comprises: i) 50.0 to 70.0% by weight of the first polypropylene (PP1) relative to the total weight of the polyolefin composition (PC); ii) 5.0 to 20.0% by weight of the first elastomeric ethylene copolymer (EC1) relative to the total weight of the polyolefin composition (PC); iii) 5.0 to 15.0% by weight of ethylene-propylene-diene monomer rubber masterbatch composition (MB) relative to the total weight of the polyolefin composition (PC); iv) 5.0 to 25.0% by weight of the filler (F) relative to the total weight of the polyolefin composition (PC); and v) Optionally, 0.1 to 5.0% by weight of additive (A) relative to the total weight of the polyolefin composition (PC). The total content of the first polypropylene (PP1), the first elastomeric ethylene copolymer (EC1), the ethylene-propylene-diene monomer rubber masterbatch composition (MB), the filler (F), and the optional additive (A) relative to the total weight of the polyolefin composition (PC) is at least 90 by weight.

5. The polyolefin composition (PC) according to any one of claims 1 to 3, wherein the first polypropylene (PP1) is a first propylene copolymer. The melt flow rate (MFR2) of the first propylene copolymer, as determined according to ISO 1133 at 230°C and 2.16 kg, is in the range of 8.0 to 115 g / 10 min.

6. The polyolefin composition (PC) according to claim 5, wherein the first polypropylene (PP1) is a first propylene-ethylene copolymer with an ethylene content in the range of 2.0 to 30.0% by weight.

7. The polyolefin composition (PC) according to any one of claims 1 to 3, wherein the first elastomeric ethylene copolymer (EC1) is a copolymer of ethylene and one or more comonomers selected from C5 to C12 α-olefins, wherein the first elastomeric ethylene copolymer (EC1) has one or two of the following properties: a) Melt flow rate (MFR2) measured according to ISO 1133 at 190 °C and 2.16 kg, in the range of 0.3 to 10 g / 10 min; and b) Density measured according to ISO 1183-187 is between 860 and 880 g / cm³. 3 Within the range.

8. The polyolefin composition (PC) according to any one of claims 1 to 3, wherein the second polypropylene (PP2) is a second propylene copolymer. The melt flow rate (MFR2) of the second propylene copolymer, as determined according to ISO 1133 at 230°C and 2.16 kg, is in the range of 0.3 to 35 g / 10 min.

9. The polyolefin composition (PC) according to claim 8, wherein the second polypropylene (PP2) is a second propylene-ethylene copolymer with an ethylene content in the range of 2.0 to 30.0% by weight.

10. The polyolefin composition (PC) according to any one of claims 1 to 3, wherein the second elastomeric ethylene copolymer (EC2) is a copolymer of ethylene and one or more comonomers selected from C5 to C12 α-olefins, wherein the second elastomeric ethylene copolymer (EC2) has one or two of the following properties: a) Melt flow rate (MFR2) measured according to ISO 1133 at 190 °C and 2.16 kg, in the range of 0.3 to 15 g / 10 min; and b) Density measured according to ISO 1183-187 is between 860 and 880 g / cm³. 3 Within the range.

11. The polyolefin composition (PC) according to any one of claims 1 to 3, wherein the ethylene-propylene-diene monomer rubber (EPDM) is a terpolymer of ethylene, propylene, and ethylene norbornene (ENB), having one or more or all of the following properties: i) Mooney viscosity M measured at 125°C according to ASTM D1646. L Within the range of 40 to 100 MU; ii) Ethylene content (C2) is in the range of 50 to 90% by weight; iii) The ethylidene norbornene content (ENB) is in the range of 1.0 to 10.0%; and iv) Density measured according to ISO 1183-187 is between 0.80 and 0.96 g / cm³. 3 Within the range.

12. The polyolefin composition (PC) according to any one of claims 1 to 3, wherein the filler (F) is an inorganic filler.

13. The polyolefin composition (PC) according to claim 12, wherein the filler (F) is selected from the group consisting of talc, calcium carbonate, barium sulfate, mica, and mixtures thereof.

14. A method for producing a polyolefin composition (PC) according to any one of claims 1 to 13, comprising the following steps: a) Provides a first polypropylene (PP1) as described in any one of claims 1, 2, 3, 5, or 6; a first elastomeric ethylene copolymer (EC1) as described in any one of claims 1, 2, 3, or 7; an ethylene-propylene-diene monomer rubber masterbatch composition (MB) as described in any one of claims 1, 2, 3, 8, 9, 10, or 11; a filler (F) as described in any one of claims 1, 12, or 13; and optional additives (A); b) The first polypropylene (PP1), the first elastomer ethylene copolymer (EC1), the ethylene-propylene-diene monomer masterbatch composition (MB), the filler (F), and optional additives (A) are blended and extruded in an extruder at a temperature in the range of 120 to 250°C to produce the polyolefin composition (PC).

15. The method of claim 14, further comprising the following step after step b): c) Injection mold the polyolefin composition (PC) produced in step b) to form an injection molded article. The injection molding described therein is glossy surface injection molding.

16. A polyolefin composition (PC), wherein the polyolefin composition (PC) is obtained by the method according to claim 14.

17. An injection-molded article comprising at least 90% by weight of a polyolefin composition (PC) according to any one of claims 1 to 13 or 16.

18. The injection-molded article according to claim 17, which is obtained by the method according to claim 15.

19. The injection molded article according to claim 17 or 18, wherein it is a glossy surface injection molded article having no more than 10 pinhole defects per 150 mm × 100 mm surface area.

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