Modified polymer recyclate

Abstract

The present invention relates to a polymer composition comprising at least the following components: A) 75 wt.-% to 95.5 wt.-% of a polymer blend, based on the total weight of the polymer composition, the polymer blend comprising a1) polypropylene; a2) polyethylene; wherein the weight ratio of a1) to a2) is from 3:7 to 9:1; and wherein the polymer blend A) is recycled material; (B) 4.5 wt.-% to 25 wt.-% of virgin ethylene alkyl (meth)acrylate, based on the total weight of the polymer composition, the virgin ethylene alkyl (meth)acrylate having the following properties: an MFR2 (190°C, 2.16 kg) measured according to ISO 1133 of 0.1 g / 10 min to 15 g / 10 min; and an alkyl (meth)acrylate content of 5 wt.-% to 40 wt.-%, based on the total weight of component B); with the proviso that the weight proportions of components A) and B) total 100 wt.-%. Furthermore, the present invention relates to a process for preparing the polymer composition according to the invention, to the use of component (B) for increasing the tensile strain at break measured according to ISO 527-2; and / or increasing the Charpy notched impact strength measured according to ISO 179-1eA at 23° C. of a polymer blend A) made of recycled material, the polymer blend A) comprising a1) polypropylene and a2) polyethylene, wherein the weight ratio of a1) to a2) is from 3:7 to 9:1, and to articles comprising the polymer composition.

Description

Technical Field

[0001] The present invention relates to a polymer composition comprising a specific recyclate blend and a specific virgin ethylene alkyl (meth)acrylate, a process for preparing the polymer composition and the use of the virgin ethylene alkyl (meth)acrylate for improving the mechanical properties of the specific recyclate blend. Background Art

[0002] Polyolefins, in a wide range of applications (including packaging of food and other items, sets, automotive parts and various products), particularly polyethylene and polypropylene, are consumed in increasing quantities. The reason for this is not only the favorable price / performance ratio, but also the high versatility and very wide range of possible modifications of these materials, which allow customizing end-use properties in a wide range of applications. Chemical modification, copolymerization, blending, stretching, thermal treatment and the combination of these technologies can convert ordinary grade polyolefins into valuable products with desired properties. This results in a large amount of polyolefin materials being produced for consumer applications.

[0003] Over the past decade, concerns have arisen about the environmental sustainability of plastics and their current use. This has led to new legislation regarding the disposal, collection, and recycling of polyolefins. Furthermore, efforts have been made in several countries to increase the percentage of plastic materials that are recycled rather than sent to landfills.

[0004] A major trend in the polyolefin sector is the use of recycled materials from a variety of sources. Mechanical recycling of polymer waste from various collection systems is a major goal of current developments in this field. Recycled plastics typically consist of several types of polymers. In the case of polyolefin recyclates, a mixture of polypropylene (PP) and polyethylene (PE) is commonly found, and the PP / PE content depends not only on the raw materials but also on the recycling process. In addition, other polar polymers, such as ethylene vinyl acetate (EVA), polyamide (PA), polyethylene terephthalate (PET), etc., may not be completely removed during the sorting process and remain in the pellets of polyolefin recyclate. Therefore, the mechanical properties of mechanically recycled polyolefins are not as good as those of original PP or PE. However, there is a great need for recyclates with good mechanical properties. The prior art describes methods for improving the mechanical properties of recyclates.

[0005] CN 106543659 A relates to recycled plastic particles. The recycled plastic particles include the following components: modified recycled plastic, an intumescent flame retardant, barium sulfate, graphene, an antioxidant, a brightener, and a plasticizer. The recycled plastic is modified by a compatibilizer, a toughening agent, and a chain extender in the process.

[0006] EP 3145 995A2 relates to the recycling of polyamide and polyolefin waste and fiber-reinforced plastic waste. In particular, it relates to polymer blends and homogeneous polymer agglomerates comprising polyamide and polyolefin waste or co-extruded film waste and glass fiber-reinforced plastic waste, and a single-stage continuous process for preparing the agglomerates.

[0007] US2015 / 0037557 A1 relates to film compositions and articles comprising recycled elastomers. The compositions include one or more virgin polymers. Optionally, the films may also include one or more compatibilizers compatible with the polymer and thermoplastic elastomer (TPE), such as block copolymers having hard and soft segments. Multilayer or monolayer films are possible. The films can be used as packaging films or component films for consumer products.

[0008] CN 107286701 A relates to a method for preparing recycled microparticles from waste plastics. The method comprises the following steps: melting and mixing raw materials at 240°C to 340°C, the raw materials comprising, by weight, 80 to 95 parts of waste plastics, 2 to 3 parts of a heat stabilizer, 4 to 9 parts of a composite toughening agent, and 1 to 3 parts of a heat dispersant; and sequentially performing extrusion, drawing, cooling, and pelletizing.

[0009] Known polymer compositions comprising recycled materials still show some disadvantages.There is a need for recycle based polymer compositions having improved mechanical properties, in particular improved Charpy notched impact strength and tensile strain at break. Summary of the Invention

[0010] The object of the present invention is to overcome the disadvantages of polymer compositions according to the prior art. In particular, it is an object of the present invention to provide a polymer composition having high toughness as indicated by Charpy notched impact strength and tensile strain at break.

[0011] This object is achieved by the polymer composition according to claim 1 of the present invention, which comprises at least the following components:

[0012] A) 75 wt.-% to 95.5 wt.-%, based on the total weight of the polymer composition, of a polymer blend comprising:

[0013] a1) Polypropylene;

[0014] a2) Polyethylene;

[0015] wherein the weight ratio of a1) to a2) is 3:7 to 9:1; and

[0016] wherein the polymer blend A) is a recycled material;

[0017] B) 4.5 wt.-% to 25 wt.-%, based on the total weight of the polymer composition, of a virgin ethylene alkyl (meth)acrylate having the following properties:

[0018] an MFR2 (190°C, 2.16 kg) measured according to ISO 1133 of 0.1 g / 10 min to 15 g / 10 min; and

[0019] an alkyl (meth)acrylate content of 5 to 40 wt.-%, based on the total weight of component B);

[0020] The proviso is that the weight proportions of components A) and B) add up to 100 wt.-%.

[0021] Advantageous embodiments of the polymer composition according to the invention are specified in dependent claims 2 to 11.

[0022] Claim 12 of the present invention relates to a method for preparing a polymer composition according to any one of claims 1 to 11, comprising the following steps:

[0023] i) providing from 75 wt.-% to 95.5 wt.-%, based on the total weight of the polymer composition, of a1)

[0024] Polymer blends A) of polypropylene and a2) recycled materials of polyethylene, wherein a1)

[0025] The weight ratio of a2) is 3:7 to 9:1;

[0026] ii) providing a raw ethylene alkyl (meth)acrylate B) having the following properties:

[0027] an MFR2 (190°C, 2.16 kg) measured according to ISO 1133 of 0.1 g / 10 min to 15 g / 10 min; and

[0028] an alkyl (meth)acrylate content of 5 to 40 wt.-%, based on the total weight of component B);

[0029] iii) melting and mixing components A) and B) to obtain a polymer composition; and

[0030] iv) Optionally, cooling the polymer composition obtained in step iii) and / or pelletizing the polymer composition.

[0031] Claims 12 and 13 specify preferred embodiments of the method according to the invention.

[0032] Claim 14 relates to the use of a raw ethylene alkyl (meth)acrylate B) having the following properties:

[0033] an MFR2 (190°C, 2.16 kg) measured according to ISO 1133 of 0.1 g / 10 min to 15 g / 10 min; and

[0034] an alkyl (meth)acrylate content of 5 to 40 wt.-%, based on the total weight of component B);

[0035] Polymer blends for increasing recycled content A)

[0036] Tensile strain at break measured according to ISO 527-2; and / or

[0037] Charpy notched impact strength measured at 23°C according to ISO 179-1eA,

[0038] The polymer blend A) of recycled materials comprises a1) polypropylene and a2) polyethylene,

[0039] wherein the weight ratio of a1) to a2) is 3:7 to 9:1;

[0040] Thereby, the original ethylene alkyl (meth)acrylate B) is present in an amount of 4.5 wt.-% to 25 wt.-%, based on the total weight of components A) and B).

[0041] Claim 15 relates to an article comprising the polymer composition according to the invention. DETAILED DESCRIPTION

[0042] definition

[0043] Quantity Indication

[0044] The polymer composition according to the invention comprises components A) and B) and optional additives. The requirement here is that components A) and B) and additives (if present) total 100 wt.-%. The indicated fixed ranges for the amounts of the individual components A) and B) and optional additives should be understood as meaning that any amount of each individual component can be selected within the specified range, provided that the strict requirement that the sum of all components A), B) and optional additives totals 100 wt.-% is met.

[0045] For the purposes of this specification and the subsequent claims, the term "recycled" is used to indicate that the material is recovered from post-consumer waste and / or industrial waste. That is, post-consumer waste refers to items that have completed at least a first use cycle (or life cycle), i.e., have passed through the hands of a consumer and have fulfilled their first purpose; while industrial waste refers to manufacturing waste that is generally not given to consumers. In the gist of the present invention, "recycled polymer" may also include, based on the total weight of the recycled polymer, up to 17 wt.-%, preferably up to 3 wt.-%, more preferably up to 1 wt.-%, even more preferably up to 0.1 wt.-% of other components from the first use. The type and amount of these components affect the physical properties of the recycled polymer. The physical properties given below refer to the main components of the recycled polymer.

[0046] Typical additional components from the first use are thermoplastic polymers such as polystyrene and PA 6, talc, chalk, ink, wood, paper, limonene, and fatty acids. The polystyrene (PS) and polyamide 6 (PA 6) contents in the recycled polymer can be determined by Fourier transform infrared spectroscopy (FTIR), and the talc, chalk, wood, and paper contents can be determined by thermogravimetric analysis (TGA).

[0047] The term "virgin" refers to materials and / or articles that are newly produced before first use and have not been recycled. Where the source of a polymer is not explicitly mentioned, then the polymer is "virgin" polymer.

[0048] Where the term "comprising" is used in this specification and claims, it does not exclude other non-specified elements of major or minor functional importance. For the purposes of the present invention, the term "consisting of" is considered a preferred embodiment of the term "comprising..." If a group is defined hereinafter as comprising at least a certain number of embodiments, this should also be understood as disclosing a group that preferably consists only of these embodiments.

[0049] Whenever the terms "including" or "having" are used, these terms are equivalent to "comprising" as defined above.

[0050] Where an indefinite or definite article is used when referring to a singular noun eg "a", "an" or "the", this includes a plural of that noun unless something else is specifically stated.

[0051] Component A)

[0052] The polymer composition according to the present invention comprises as component A) 75 wt.-% to 95.5 wt.-%, based on the total weight of the polymer composition, of a polymer blend comprising a1) polypropylene; a2) polyethylene; wherein the weight ratio of a1) to a2) is from 3:7 to 9:1; and wherein the polymer blend A) is recycled material.

[0053] Preferred embodiments of component A) will be discussed below.

[0054] According to a preferred embodiment of the present invention, component A) comprises 80.0 wt.-% to 99.9 wt.-%, preferably 90.0 wt.-% to 99.0 wt.-%, more preferably 94.0 wt.-% to 98.0 wt.-% of polypropylene a1) and polyethylene a2), based on the total weight of component A).

[0055] A further preferred embodiment of the present invention provides that component A) comprises less than 5 wt.-%, preferably less than 3 wt.-%, more preferably from 0.01 wt.-% to 2 wt.-% of thermoplastic polymers other than a1) and a2), based on the total weight of component A), preferably less than 4.0 wt.-% of PA 6 and less than 5 wt.-% of polystyrene, more preferably component A) comprises from 0.01 wt.-% to 4 wt.-% of polystyrene.

[0056] In another preferred embodiment according to the present invention, component A) comprises less than 5 wt.-%, preferably less than 4 wt.-%, more preferably 0.01 to 3 wt.-% talc, based on the total weight of component A).

[0057] According to another preferred embodiment of the present invention, component A) comprises less than 4 wt.-%, preferably less than 3 wt.-%, more preferably 0.01 to 2 wt.-% chalk, based on the total weight of component A).

[0058] According to another preferred embodiment of the invention, component A) comprises less than 1 wt.-%, preferably less than 0.5 wt.-%, more preferably 0.01 wt.-% to 1 wt.-% of paper, based on the total weight of component A).

[0059] In another preferred embodiment of the present invention, component A) comprises less than 1 wt.-%, preferably less than 0.5 wt.-%, more preferably 0.01 to 1 wt.-% of wood, based on the total weight of component A).

[0060] According to another preferred embodiment of the present invention, component A) comprises less than 1 wt.-%, preferably less than 0.5 wt.-%, more preferably 0.01 to 1 wt.-% of metals, based on the total weight of component A).

[0061] In another preferred embodiment according to the present invention, component A) comprises less than 100 ppm, preferably 0.1 ppm to 100 ppm, of limonene, based on the total weight of component A).

[0062] According to a further preferred embodiment of the invention, it is provided that component A) comprises less than 200 ppm, preferably from 1 ppm to 200 ppm, of fatty acids, based on the total weight of component A).

[0063] In another preferred embodiment according to the present invention, component A) is a recycled material which is recovered from waste plastic material from post-consumer and / or post-industrial waste.

[0064] In another preferred embodiment of the present invention, component A) has an MFR2 (230° C., 2.16 kg), determined according to ISO 1133, of 2 to 50 g / 10 min, preferably 4 to 25 g / 10 min, more preferably 4 to 8 g / 10 min.

[0065] According to another preferred embodiment of the invention, the content of component A) in the polymer composition is 76 wt.-% to 95.1 wt.-%, preferably 77 wt.-% to 95 wt.-% or 80 wt.-% to 95 wt.-%, based on the total weight of the polymer composition.

[0066] According to another preferred embodiment of the present invention, the content of polypropylene a1) in component A) is from 75 to 98 wt.-%, preferably from 75 to 95 wt.-%, more preferably from 76 to 85 wt.-%, still more preferably from 78 to 82 wt.-%, most preferably from 79 to 81 wt.-%, based on the total weight of component A), or the content of polypropylene a1) in component A) is from 25 to 85 wt.-%, preferably from 40 to 80 wt.-%, more preferably from 50 to 65 wt.-%, most preferably from 56 to 57 wt.-%, based on the total weight of component A). Even more preferably, component a1) comprises more than 95 wt.-%, still more preferably from 96 to 99.9 wt.-%, of isotactic polypropylene, and most preferably consists of isotactic polypropylene.

[0067] In another preferred embodiment according to the present invention, the content of polypropylene a2) in component A) is from 5 wt.-% to 25 wt.-%, preferably from 15 wt.-% to 24 wt.-%, more preferably from 18 wt.-% to 22 wt.-%, most preferably from 19 wt.-% to 21 wt.-%, based on the total weight of component A); or the content of polypropylene a2) in component A) is from 15 wt.-% to 75 wt.-%, preferably from 20 wt.-% to 60 wt.-%, more preferably from 35 wt.-% to 50 wt.-%, most preferably from 43 wt.-% to 44 wt.-%, based on the total weight of component A).

[0068] In a further preferred embodiment, the polypropylene a1) comprises one or more polymeric materials selected from the group consisting of:

[0069] I) isotactic or mostly isotactic propylene homopolymers;

[0070] II) isotactic random copolymers of propylene with ethylene and / or C4-C8 α-olefins (such as 1-butene or 1-octene), wherein the total comonomer content is from 0.05 wt.-% to 20 wt.-%, or mixtures of said copolymers with isotactic or mostly isotactic propylene homopolymers;

[0071] III) Heterophasic copolymers comprising an isotactic propylene homopolymer, such as (I), or a random copolymer of propylene, such as (II), and an elastomeric fraction comprising a copolymer of ethylene with propylene and / or a C4-C8 α-olefin, such as 1-butene or 1-octene, optionally containing a small amount of a diene, such as butadiene, 1,4-hexadiene, 1,5-hexadiene, ethylidene-1-norbornene.

[0072] Another preferred embodiment of the present invention provides that component a1) has a density of 0.895 g / cm 3 to 0.920g / cm 3 , preferably 0.900g / cm 3 to 0.915g / cm 3 density.

[0073] According to another embodiment of the present invention, component a1) has a melt index (MFR) of 0.5 g / 10 min to 300 g / 10 min, preferably 1.0 g / 10 min to 150 g / 10 min, or 1.5 g / 10 min to 50 g / 10 min, measured according to ISO 1133 (at 230° C.; under a load of 2.16 kg).

[0074] In another preferred embodiment of the present invention, component a1) has a melting temperature of 130 to 170° C., preferably 140 to 168° C., more preferably 142 to 166° C. In case it is a propylene homopolymer as described in item (I) above, it will have a melting temperature of 150 to 170° C., preferably 155 to 168° C., and more preferably 160 to 166° C., as determined by differential scanning calorimetry (DSC) according to ISO 11357-3. In case it is a random propylene copolymer as described in item (II) above, it will have a melting temperature of 130 to 162° C., preferably 135 to 160° C., more preferably 140 to 158° C., as determined by DSC according to ISO 11357-3.

[0075] The polyethylene a2) is preferably a high density polyethylene (HDPE) or a linear low density polyethylene (LLDPE) or a long chain branched low density polyethylene (LDPE). The comonomer content of component a2) is typically below 50 wt.-%, preferably below 25 wt.-%, most preferably below 15 wt.-%.

[0076] In this context, HDPE suitable for use as component a2) has a density equal to or greater than 0.941 g / cm², measured according to ISO 1183. 3 , preferably 0.941g / cm 3 to 0.965g / cm 3 , more preferably 0.945g / cm 3 to 0.960g / cm 3 density.

[0077] According to another preferred embodiment, the HDPE is an ethylene homopolymer. HDPE suitable for use as component a2) in the present disclosure typically has an MFR, measured by ISO 1133 (at 190° C.; under a load of 2.16 kg), of 0.01 to 50 g / 10 min, preferably 0.1 to 30 g / 10 min, such as 0.5 to 20 g / 10 min.

[0078] HDPE may also be a copolymer, for example a copolymer of ethylene and one or more α-olefin monomers (eg, propylene, butene, hexene, etc.).

[0079] LLDPE suitable for use as component a2) in the present disclosure typically has a OD of 0.900 g / cm² as measured by ISO 1183. 3 to 0.920g / cm 3 , or 0.905g / cm 3 to 0.918g / cm 3 , or 0.910g / cm 3to 0.918g / cm 3 The LLDPE is a copolymer, for example, a copolymer of ethylene and one or more α-olefin monomers (such as propylene, butene, hexene, etc.).

[0080] LDPE suitable for use as component a2) in the present disclosure typically has a OD of 0.915 g / cm² as measured by ISO 1183. 3 to 0.935g / cm 3 and an MFR of 0.01 to 20 g / min, measured by ISO 1133 (190° C.; 2.16 kg). LDPE is an ethylene homopolymer.

[0081] According to another preferred embodiment, the melting temperature of component a2) is from 100°C to 135°C, preferably from 105°C to 132°C.

[0082] Such post-consumer and / or post-industrial waste can come from, in particular, waste electrical and electronic equipment (WEEE) or end-of-life vehicles (ELV), or from different waste collection schemes, such as the German DSD system, the Austrian ARA system and the Austrian ASZ system (in particular for Purpolen material) or the Italian "Raccolta Differziata" system.

[0083] Recycled materials are commercially available from, for example, Corpela (an Italian consortium for the collection, recovery, packaging and recycling of plastic waste), Resource Plastics Corp. (Brampton, ON), Kruschitz GmbH, Plastics and Recycling (AT), Ecoplast (AT), Vogt Plastak GmbH (DE), mtm Plastics GmbH (DE), etc.

[0084] A preferred recycled polymer blend is Purpolen PP, which is a recycled polymer mixture comprising polyethylene and polypropylene, available from mtm plastics GmbH, Niedergebra, Germany. Another preferred recycled polymer blend is Dipolen, which is a recycled polymer mixture comprising polyethylene and polypropylene, available from mtm plastics GmbH, Niedergebra, Germany.

[0085] Component B)

[0086] The polymer composition according to the invention comprises as component B) 4.5 to 25 wt.-%, based on the total weight of the polymer composition, of virgin ethylene alkyl (meth)acrylate having the following properties: an MFR2 (190° C., 2.16 kg) of 0.1 to 15 g / 10 min, determined according to ISO 1133; and an alkyl (meth)acrylate content of 5 to 40 wt.-%, based on the total weight of component B).

[0087] Preferred embodiments of component B) will be discussed below.

[0088] According to a preferred embodiment of the present invention, component B) is an ethylene alkyl acrylate, preferably ethylene methyl acrylate and / or ethylene butyl acrylate.

[0089] According to a further preferred embodiment of the present invention, component B) is ethylene methyl acrylate having an MFR2 (190° C., 2.16 kg), determined according to ISO 1133, of 0.1 g / 10 min to 10 g / 10 min, preferably 0.2 g / 10 min to 5 g / 10 min, more preferably 0.4 g / 10 min to 1.0 g / 10 min; and / or a methyl acrylate content of 10 wt.-% to 35 wt.-%, preferably 15 wt.-% to 30 wt.-%, more preferably 23 wt.-% to 27 wt.-%, based on the total weight of component B).

[0090] In a further preferred embodiment according to the present invention, component B) is ethylene butyl acrylate having an MFR2 (190° C., 2.16 kg), determined according to ISO 1133, of 0.1 to 10 g / 10 min, preferably 0.2 to 8 g / 10 min and more preferably 0.6 to 5.0 g / 10 min; and / or a butyl acrylate content of 10 to 40 wt.-%, preferably 12 to 35 wt.-% and more preferably 16 to 28 wt.-%, based on the total weight of component B).

[0091] A preferred ethylene methyl acrylate is available from Dow / DuPont under the tradename Elvaloy AC1125.

[0092] Preferred ethylene butyl acrylate is available from Repsol under the tradename Ebantix E1704 or Ebantix E2770.

[0093] additive

[0094] The polymer composition according to the invention may further comprise additives.

[0095] Preferably, these additives are selected from slip agents, UV stabilizers, pigments, antacids, antioxidants, antiblocking agents, antistatic agents, additive carriers, nucleating agents and mixtures thereof, more preferably at least one additive is an antioxidant, whereby these additives are preferably present in the range of 0 wt.-% to 5 wt.-%, more preferably 0.1 wt.-% to 4 wt.-%, most preferably 0.2 wt.-% to 0.4 wt.-%, based on the total weight of the polymer composition.

[0096] Examples of antioxidants that can be used are sterically hindered phenols (e.g. CAS No. 6683-19-8, also sold by BASF as Irganox 1010 FF), phosphorus-based antioxidants (e.g. CAS No. 31570-04-4, also sold by Clariant as Hostanox PAR 24 (FF) TM Sold or sold by BASF as Irgafos 168(FF) TM Sold), sulfur-based antioxidants (e.g., CAS No. 693-36-7, sold by BASF as Irganox PS-802FL TM sold herein), nitrogen-based antioxidants (e.g., 4,4′-bis(1,1′-dimethylbenzyl)diphenylamine), or antioxidant blends.

[0097] Examples of antacids that can be used in the polymer compositions of the present invention are calcium stearate, sodium stearate, zinc stearate, magnesium and zinc oxides, synthetic hydrotalcite (e.g. SHT, CAS No. 11097-59-9), lactic acid esters and salts, as well as calcium stearate (CAS No. 1592-23-0) and zinc stearate (CAS No. 557-05-1).

[0098] The antiblocking agent that can be used in the polymer composition of the present invention is natural silica, such as diatomaceous earth (such as CAS No. 60676-86-0 (SuperfFloss TM ), CAS number 60676-86-0 (SuperFloss E TM ) or CAS No. 60676-86-0 (Celite 499 TM)), synthetic silica (such as CAS No. 7631-86-9, CAS No. 7631-86-9, CAS No. 7631-86-9, CAS No. 7631-86-9, CAS No. 7631-86-9, CAS No. 7631-86-9, CAS No. 112926-00-8, CAS No. 7631-86-9 or CAS No. 7631-86-9), silicates (such as aluminum silicate (kaolin )CAS No. 1318-74-7, sodium aluminum silicate CAS No. 1344-00-9, calcined kaolin CAS No. 92704-41-1, aluminum silicate CAS No. 1327-36-2, or calcium silicate CAS No. 1344-95-2), synthetic zeolite (such as hydrated sodium aluminosilicate CAS No. 1344-01-0, CAS No. 1344-01-0, or hydrated sodium aluminosilicate CAS No. 1344-01-0).

[0099] UV stabilizers that can be used in the polymer composition according to the invention are, for example, bis-(2,2,6,6-tetramethyl-4-piperidinyl)-sebacate (CAS No. 52829-07-9, Tinuvin 770); 2-hydroxy-4-n-octyloxy-benzophenone (CAS No. 1843-05-6, Chimassorb 81).

[0100] Nucleating agents that can be used in the polymer composition of the present invention are, for example, sodium benzoate (CAS No. 532-32-1) or 1,3:2,4-bis(3,4-dimethylbenzylidene)sorbitol (CAS 135861-56-2, Millad 3988).

[0101] Suitable antistatic agents are, for example, glycerol esters (CAS No. 97593-29-8) or ethoxylated amines (CAS No. 71786-60-2 or 61791-31-9) or ethoxylated amides (CAS No. 204-393-1).

[0102] polymer composition

[0103] Preferred embodiments of the polymer composition according to the present invention will be discussed below.

[0104] According to a preferred embodiment of the present invention, the polymer composition has an MFR2 (230°C, 2.16 kg) measured according to ISO 1133 of 0.5 g / 10 min to 40 g / 10 min, preferably 1.0 g / 10 min to 10 g / 10 min or 11 g / 10 min to 25 g / 10 min, more preferably 1.5 g / 10 min to 6.5 g / 10 min or 12 g / 10 min to 20 g / 10 min.

[0105] According to a further preferred embodiment of the present invention it is provided that the polymer composition has a tensile strain at break measured according to ISO 527-2 of 10% to 750%, preferably 10% to 50% or 50% to 700%, more preferably 17% to 40% or 200% to 650%.

[0106] In another preferred embodiment according to the present invention, the polymer composition has a 2 , preferably 3.0 kJ / m 2 Up to 60kJ / m 2 , more preferably 3.0 kJ / m 2 Up to 50kJ / m 2 or 5 kJ / m 2 Up to 45kJ / m 2 Charpy notched impact strength measured at 23°C according to ISO 179-1eA.

[0107] According to another preferred embodiment of the present invention, the content of component A) in the polymer composition is 76 to 95.1 wt.-%, preferably 77 to 95 wt.-% or 80 to 95 wt.-%, based on the total weight of the polymer composition.

[0108] According to another preferred embodiment of the present invention, the content of component B) in the polymer composition is 4.9 to 24 wt.-%, preferably 5 to 23 wt.-% or 5 to 20 wt.-%, based on the total weight of the polymer composition.

[0109] According to another preferred embodiment of the present invention, the content of polypropylene a1) in component A) is from 75 to 98 wt.-%, preferably from 75 to 95 wt.-%, more preferably from 76 to 85 wt.-%, still more preferably from 78 to 82 wt.-%, most preferably from 79 to 81 wt.-%, based on the total weight of component A), or the content of polypropylene a1) in component A) is from 25 to 85 wt.-%, preferably from 40 to 80 wt.-%, more preferably from 50 to 65 wt.-%, most preferably from 56 to 57 wt.-%, based on the total weight of component A). Even more preferably, component a1) comprises more than 95 wt.-%, still more preferably from 96 to 99.9 wt.-%, of isotactic polypropylene, and most preferably consists of isotactic polypropylene.

[0110] In another preferred embodiment according to the present invention, the content of polypropylene a2) in component A) is from 5 wt.-% to 25 wt.-%, preferably from 15 wt.-% to 24 wt.-%, more preferably from 18 wt.-% to 22 wt.-%, most preferably from 19 wt.-% to 21 wt.-%, based on the total weight of component A); or the content of polypropylene a2) in component A) is from 15 wt.-% to 75 wt.-%, preferably from 20 wt.-% to 60 wt.-%, more preferably from 35 wt.-% to 50 wt.-%, most preferably from 43 wt.-% to 44 wt.-%, based on the total weight of component A).

[0111] Another preferred embodiment of the present invention provides that component B) is ethylene methyl acrylate and that the polymer composition has a tensile strain at break measured according to ISO 527-2 that is at least 10% higher, preferably from 10% to 600% higher, more preferably from 100% to 500% higher, most preferably from 300% to 500% higher than the same polymer composition without component B).

[0112] According to another preferred embodiment of the present invention, component B) is ethylene methyl acrylate and the polymer composition has a Charpy notched impact strength measured according to ISO 179-1eA at 23° C. that is at least 2% higher, preferably 10% to 800% higher, more preferably 20% to 700% higher, most preferably 100% to 650% higher than the same polymer composition without component B).

[0113] Another preferred embodiment of the present invention provides that component B) is ethylene butyl acrylate and that the polymer composition has a tensile strain at break measured according to ISO 527-2 that is at least 10% higher, preferably 20% to 600% higher, more preferably 30% to 500% higher, most preferably 200% to 500% higher than the same polymer composition without component B).

[0114] According to another preferred embodiment of the present invention, component B) is ethylene butyl acrylate and the polymer composition has a Charpy notched impact strength measured according to ISO 179-1eA at 23° C. that is at least 2% higher, preferably 10% to 1400% higher, more preferably 20% to 1300% higher, most preferably 100% to 1250% higher than the same polymer composition without component B).

[0115] Preferred polymer compositions according to the present invention comprise at least the following components and preferably consist of these components:

[0116] A) 75 wt.-% to 95 wt.-%, preferably 80 wt.-% to 95 wt.-%, based on the total weight of the polymer composition, of a polymer blend comprising

[0117] a1) Polypropylene;

[0118] a2) Polyethylene;

[0119] wherein the weight ratio of a1) to a2) is from 3:7 to 9:1, preferably from 8:1 to 11:1; and wherein the polymer blend A) is recycled material;

[0120] B) 5 wt.-% to 25 wt.-%, preferably 5 wt.-% to 20 wt.-%, based on the total weight of the polymer composition, of a raw ethylene alkyl acrylate, preferably ethylene methyl acrylate or ethylene butyl acrylate, having the following properties

[0121] MFR2 (190°C, 2.16 kg) measured according to ISO 1133 of 0.1 g / 10 min to 10 g / 10 min, preferably 0.6 g / 10 min to 5 g / 10 min; or 0.4 g / 10 min to 1 g / 10 min; and

[0122] an alkyl acrylate content of 5 to 40 wt.-%, preferably 16 to 28 wt.-% or 23 to 27 wt.-%, based on the total weight of component B);

[0123] The proviso is that the weight proportions of components A) and B) add up to 100 wt.-%.

[0124] method

[0125] The method for producing the polymer composition according to the present invention comprises the following steps:

[0126] i) providing from 75.5 wt.-% to 95.5 wt.-%, based on the total weight of the polymer composition, of a

[0127] Polymer blends A) of recycled materials of a1) polypropylene and a2) polyethylene, wherein

[0128] The weight ratio of a1) to a2) is 3:7 to 9:1;

[0129] ii) providing a raw ethylene alkyl (meth)acrylate B) having the following properties

[0130] an MFR2 (190°C, 2.16 kg) measured according to ISO 1133 of 0.1 g / 10 min to 15 g / 10 min; and

[0131] an alkyl (meth)acrylate content of 5 to 40 wt.-%, based on the total weight of component B);

[0132] iii) melting and mixing components A) and B) to obtain a polymer composition; and

[0133] iv) Optionally, cooling the polymer composition obtained in step iii) and / or pelletizing the polymer composition.

[0134] According to a preferred embodiment of the invention, component B) is ethylene methyl acrylate having an MFR2 (190° C., 2.16 kg), determined according to ISO 1133, of 0.1 to 10 g / 10 min, preferably 0.2 to 5 g / 10 min and more preferably 0.4 to 1.0 g / 10 min.

[0135] According to a further preferred embodiment of the invention, component B) has a methyl acrylate content of 10 to 35 wt.-%, preferably 15 to 30 wt.-%, more preferably 23 to 27 wt.-%, based on the total weight of component B).

[0136] According to another preferred embodiment of the present invention, component B) is ethylene butyl acrylate having an MFR2 (190° C., 2.16 kg), measured according to ISO 1133, of 0.1 to 10 g / 10 min, preferably 0.2 to 8 g / 10 min, more preferably 0.6 to 5.0 g / 10 min.

[0137] According to a further preferred embodiment of the invention, component B) has a butyl acrylate content of 10 to 40 wt.-%, preferably 12 to 35 wt.-%, more preferably 16 to 28 wt.-%, based on the total weight of component B).

[0138] All preferred aspects and embodiments described above should also apply to the method according to the invention.

[0139] use

[0140] The present invention also relates to the use of virgin ethylene alkyl (meth)acrylates B) having the following properties: an MFR2 (190° C., 2.16 kg), determined according to ISO 1133, of 0.1 g / 10 min to 15 g / 10 min; and an alkyl (meth)acrylate content of 5 wt.-% to 40 wt.-%, based on the total weight of component B); for increasing the tensile strain at break, measured according to ISO 527-2; and / or the Charpy notched impact strength, measured at 23° C., measured according to ISO 179-1eA, of a polymer blend A) of recycled material, the polymer blend A) comprising a1) polypropylene and a2) polyethylene, wherein the weight ratio of a1) to a2) is from 3:7 to 9:1; whereby the virgin ethylene alkyl (meth)acrylates B) is present in an amount of 4.5 wt.-% to 25 wt.-%, based on the total weight of components A) and B).

[0141] All preferred aspects and embodiments described above should also apply to the use of the present invention.

[0142] Products

[0143] The present invention also relates to an article comprising the polymer composition according to the present invention, preferably said article being selected from consumer goods or household goods, preferably caps, closures and packaging containers.

[0144] The invention will now be described with reference to the following non-limiting examples.

[0145] Experimental part

[0146] A. Measurement Method

[0147] Unless otherwise defined, the following definitions of terms and assay methods apply to the above general description of the invention as well as to the following examples.

[0148] Melt Flow Rate (MFR)

[0149] The MFR of polypropylene is measured at 230°C under a load of 2.16 kg (MFR2) and the MFR of polyethylene is measured at 190°C under a load of 2.16 kg (MFR2) according to ISO 1133. For compounds comprising a mixture of polypropylene and polyethylene, the MFR is measured at 230°C under a load of 2.16 kg (MFR2) and at 190°C under a load of 2.16 kg (MFR2).

[0150] Melting temperature T m , crystallization temperature T c and melting enthalpy H m

[0151] The melting temperature of 5 mg to 7 mg samples was determined using a TA Instruments Q2000 differential scanning calorimeter (DSC). The DSC was operated according to ISO 11357 / Part 3 / Method C2 in a heating / cooling / heating cycle at a scan rate of 10°C / min over a temperature range of -30°C to +225°C. The crystallization temperature (T) was determined from the cooling step. c ), while the melting temperature (T m ) and melting enthalpy (H m For the calculation of the melting enthalpy, 50°C was used as the lower integration limit. The melting temperature and crystallization temperature were taken as the peaks of the endotherm and exotherm.

[0152] Tensile modulus and tensile strain at break

[0153] The measurements of the test specimens were carried out after a conditioning time of 96 hours (at 23° C., 50% relative humidity).

[0154] Tensile modulus was measured according to ISO 527-2 (crosshead speed = 1 mm / min; 23°C) using injection moulded specimens as described in EN ISO 1873-2 (dog bone shape, 4 mm thickness).

[0155] Tensile strain at break was measured according to ISO 527-2 (crosshead speed = 50 mm / min; 23° C.) using injection molded specimens as described in EN ISO 1873-2 (dog bone shape, 4 mm thickness).

[0156] Simple supported beam notched impact strength

[0157] According to ISO 1791eA, at 23 ° C, using 80 × 10 × 4 mm injection molded according to EN ISO 1873-2 3 The Charpy notched impact strength (after conditioning for 96 hours at 23° C. and 50% relative humidity) was determined using test strips of the same material.

[0158] density

[0159] The density of the material is measured according to ISO 1183-1.

[0160] Determination of butyl acrylate and methyl acrylate content in EBA and EMA

[0161] The determination of the polar comonomer content of ethylene butyl acrylate and ethylene methyl acrylate is illustrated below by way of example. The wt.-% can be converted to mol-% by calculation and is well documented in the literature.

[0162] (1) Ethylene copolymer containing butyl acrylate

[0163] Film samples of the polymers were prepared for FTIR measurements: 0.5 mm to 0.7 mm thickness for ethylene butyl acrylate with butyl acrylate content > 6 wt.-% and 0.05 mm to 0.12 mm thickness for ethylene butyl acrylate with butyl acrylate content < 6 wt.-%.

[0164] After FT-IR analysis, samples with >6 wt.-% butyl acrylate were analyzed at 3450 cm -1 The maximum absorbance of the peak at 3510 cm minus the maximum absorbance at 3510 cm -1 The absorbance value of the baseline at 丙烯酸丁酯 -A3510). Then use the polyethylene peak at 2020cm -1 The maximum absorbance peak at 2120 cm minus the maximum absorbance peak at 2120 cm -1 The absorbance value of the baseline at 2020 -A 2120 ). Then calculate (A 丙烯酸丁酯 -A 3510 ) and (A 2020 -A 2120 ), which is well documented in the literature.

[0165] The samples with comonomer butyl acrylate <6 wt.-% were detected at 1165 cm -1 The maximum absorbance of the peak at 1865 cm minus the maximum absorbance of the peak at 1865 cm -1 The absorbance value of the baseline at 丙烯酸丁酯 -A 1865 ). Then use the polyethylene peak at 2660cm -1 The maximum absorbance peak at 1865 cm minus the maximum absorbance peak at 1865 cm -1 The absorbance value of the baseline (A 2660 -A 1865 Then calculate (A 丙烯酸丁酯 -A 1865 ) and (A 2660 -A 1865 ) between them.

[0166] (2) Ethylene copolymer containing methyl acrylate

[0167] Film samples of the polymers were prepared for FTIR measurements: 0.1 mm thickness for ethylene methyl acrylate with methyl acrylate content > 8 wt.-% and 0.05 mm thickness for ethylene methyl acrylate with methyl acrylate content < 8 wt.-%.

[0168] After analysis, samples with >8 wt.-% methyl acrylate were detected at 3455 cm -1 The maximum absorbance of the peak at 3510 cm minus the maximum absorbance at 3510 cm -1 The absorbance value of the baseline (A丙烯酸甲酯 -A 3510 ). Then use the polyethylene peak at 2675cm -1 The maximum absorbance peak at 2450 cm minus the maximum absorbance peak at 2450 cm -1 The absorbance value of the baseline (A 2675 -A 2450 ). Then calculate (A 丙烯酸甲酯 -A 3510 ) and (A 2675 -A 2450 ), which is well documented in the literature.

[0169] The samples with <8 wt.% of methyl acrylate as comonomer were detected at 1164 cm -1 The maximum absorbance of the peak at 1850 cm minus the maximum absorbance at 1850 cm -1 The absorbance value of the baseline (A 丙烯酸甲酯 -A 1850 ). Then use the polyethylene peak at 2665cm -1 The maximum absorbance peak at 1850 cm minus the maximum absorbance peak at 1850 cm -1 The absorbance value of the baseline (A 2665 -A 1850 Then calculate (A 丙烯酸甲酯 -A 1850 ) and (A 2665 -A 1850 ) between them.

[0170] Component A) Determination of the content of isotactic polypropylene (iPP), polystyrene (PS), ethylene, PVC and polyamide-6

[0171] Sample preparation

[0172] All calibration samples and samples to be analyzed were prepared in a similar manner on melt pressed plates. Approximately 2 g to 3 g of the compound to be analyzed were melted at 190 ° C. Subsequently, a pressure of 60 to 80 bar was applied in a hydraulic hot press for 20 seconds. Next, the sample was cooled to room temperature within 40 seconds in a cold press under the same pressure in order to control the morphology of the compound. The thickness of the plate was controlled by a 2.5 cm × 2.5 cm metal calibration frame plate with a thickness of 100 μm to 200 μm (depending on the MFR of the sample); two plates were produced in parallel at the same time and under the same conditions. The thickness of each plate was measured before any FTIR measurement; the thickness of all plates was between 100 μm and 200 μm.

[0173] In order to control the plate surface and avoid any disturbance during the measurement, all plates were pressed between two sheets of double-sided silicone release paper.

[0174] In the case of powder samples or heterogeneous compounds, the pressing process was repeated three times to increase homogeneity by pressing and cutting the samples under the same conditions as above.

[0175] Spectrometer:

[0176] A standard transmission FTIR spectrometer is used, such as a Bruker Vertex 70 FTIR spectrometer with the following settings:

[0177] Spectral range: 4000cm -1 -400cm -1 ,

[0178] The aperture is 6mm,

[0179] Spectral resolution is 2cm -1 ,

[0180] 16 background scans, 16 spectrum scans,

[0181] The interferogram zero filling factor is 32,

[0182] Norton Beer has strong apodisation.

[0183] Spectra were recorded and analyzed in Bruker Opus software.

[0184] Calibration samples:

[0185] Since FTIR is a secondary method, several calibration standards are mixed to cover the analytical range of interest, typically:

[0186] 0.2 wt.-% to 2.5 wt.-% PA

[0187] PS 0.1 wt.-% to 5 wt.-%

[0188] PET 0.2 wt.-% to 2.5 wt.-%

[0189] PVC is 0.1wt.-% to 4wt.-%

[0190] The following commercial materials were used for the compounds: Borealis HC600TF as iPP, Borealis FB3450 as HDPE and for target polymers, such as RAMAPET N1S (Indoamamer Polymer) for PET, B36LN (BASF) for polyamide 6, polystyrene diluent PS 486N (Ineos) for high-impact polystyrene (HIPS) and Inovyn PVC 263B (powder form) for PVC.

[0191] All compounds were prepared on a small scale in a Haake kneader at temperatures below 265° C. and for a time period of less than 10 minutes to avoid degradation. Additional antioxidants such as Irgafos 168 (3000 ppm) were added to minimize degradation.

[0192] calibration:

[0193] The principle of FTIR calibration is the same for all components: the intensity of a specific FTIR band divided by the plate thickness is the same as the intensity of the band on the same plate. 1 H or 13 C is related to the amount of the component determined by solution-state NMR.

[0194] Each specific FTIR absorption band is selected because the intensity of each specific FTIR absorption band increases with increasing concentration of the component regardless of the composition of the calibration standard sample and the authentic sample, and each specific FTIR absorption band is isolated from the remaining peaks.

[0195] The method is described in the publication "Alterations of plastic spectra in MIR and the potential impacts on identification towards recycling" by Signott et al., Resources, conservation and Recycling journal, 2020, volume 161, article 104980.

[0196] The wavelength of each calibration band is:

[0197] PA is 3300cm -1 ,

[0198] PS is 1601cm -1 ,

[0199] PET is 1410cm -1 ,

[0200] PVC is 615cm -1 ,

[0201] iPP is 1167cm -1 .

[0202] For each polymer component i, a linear calibration (linearity based on the Beer-Lambert law) is constructed. A typical linear correlation for such a calibration is given below:

[0203]

[0204] Among them, x i is the fraction content of polymer component i (in wt%).

[0205] E i is the absorbance intensity (expressed in au absorbance units) of the specific bands associated with polymer component i. These specific bands are: PA at 3300 cm -1 、PS is 1601cm -1 、PET is 1410cm -1 、PVC is 615cm -1 、iPP is 1167cm -1 .

[0206] d is the thickness of the sample plate.

[0207] A i and B i are the two correlation coefficients determined for each calibration curve

[0208] No specific isolated band was found for the C2-rich fraction, so the C2-rich fraction was estimated indirectly.

[0209] x C2rich =100-(x iPP +x PA +x PS +x PET +x EVA +x PVC +x 白垩 +x 滑石 )

[0210] The contents of EVA, chalk and talc are estimated "semi-quantitatively". This therefore makes the C2-rich content "semi-quantitative".

[0211] For each calibration standard, whenever available, the amount of each component is given by 1 H or 13 Solution-state NMR was used as the primary method (except for PA). NMR measurements were performed on the exact same FTIR plate used to construct the FTIR calibration curve.

[0212] Calibration standards were prepared by mixing iPP and HDPE to create a calibration curve. The thickness of the calibration standard film was 300 μm. To quantify the iPP, PS, and PA6 content in the samples, quantitative IR spectra were recorded in the solid state using a Bruker Vertex 70 FTIR spectrometer. Spectra were recorded on 25 mm × 25 mm square films with a thickness of 50 μm to 100 μm, prepared by compression molding at 190 °C and 4 mPa to 6 mPa. Standard transmission FTIR spectroscopy was used, using a 4000 cm-1 Up to 400cm -1 spectral range, 6mm aperture, 2cm spectral resolution, 16 background scans, 16 spectral scans, an interferogram zero filling factor of 32, and strong Norton-Beer apodization.

[0213] Measured at 1167cm -1 The absorbance of the bands in the iPP was determined and the iPP content was quantified according to the calibration curve (the units of absorbance / thickness were cm and the units of iPP content were wt.-%).

[0214] Measured at 1601cm -1 (PS) and 3300cm -1 The absorbance of the band at (PA6) was measured, and the PS and PA6 contents were quantified using a calibration curve (absorption / thickness in cm and iPP content in wt.%). The ethylene content was determined by subtracting the iPP, PS, and PA6 contents from 100. The analysis was performed using a duplex method.

[0215] Amount of talc and chalk

[0216] The amount of talc and chalk was measured by thermogravimetric analysis (TGA); the experiment was performed using a Perkin Elmer TGA 8000. Approximately 10 to 20 mg of material was placed in a platinum pan. This was equilibrated at 50°C for 10 minutes, then the temperature was increased to 950°C under nitrogen at a heating rate of 20°C / min. The weight loss of Ca (WCO2) between 550°C and 700°C was attributed to CO2 released by CaCO3, so the chalk content was estimated as:

[0217] Chalk content = 100 / 44×WCO2

[0218] Afterwards, the temperature was lowered to 300°C at a cooling rate of 20°C / min. The gas was then switched to oxygen and the temperature was raised again to 900°C. The weight loss in this step was attributed to carbon black (Wcb). Knowing the contents of carbon black and chalk, the ash content excluding chalk and carbon black was calculated as:

[0219] Ash content = (ash residue) - 56 / 44 × WCO2 - Wcb

[0220] Therein, the ash residue is the wt.-% measured at 900° C. in a first step carried out under nitrogen. The ash content was estimated to be identical to the talc content for the recyclate studied.

[0221] Amount of paper and wood

[0222] Paper and wood were determined by conventional laboratory methods including grinding, flotation, microscopy and thermogravimetric analysis (TGA).

[0223] Amount of metal

[0224] The amount of metal was determined by X-ray fluorescence (XRF).

[0225] Amount of limonene

[0226] The amount of limonene was determined by solid phase microextraction (HS-SPME-GC-MS).

[0227] Total fatty acid content

[0228] The amount of total fatty acids was determined by solid phase microextraction (HS-SPME-GC-MS).

[0229] B. Materials used

[0230] Component A)

[0231] Purpolen PP

[0232] Purpolen PP is a recycled polymer mixture comprising polyethylene and polypropylene obtained from mtm plastics GmbH, Niedergebra, Germany. Table 1 below shows the composition of the batches used in the working examples.

[0233] Table 1: Composition of Purpolen PP used in the working examples.

[0234]

[0235] The content of components a1) and a2) in Purpolen PP adds up to 100 wt.-% with PS (0.1 wt.-%), talc (0.7 wt.-%), chalky PA6 (0.2 wt.-%) (content also determined by FTIR) and small amounts of other substances (the MFR2 (230° C.) of the Purpolen PP used was 20.9 g / 10 min).

[0236] Dipolen S

[0237] Dipolen S is a recycled polymer mixture comprising polyethylene and polypropylene obtained from mtm plastics GmbH, Niedergebra, Germany. Table 2 below shows the composition of the batches used in the working examples.

[0238] Table 2: Composition of Dipolen S used in the working examples.

[0239]

[0240] The content of components a1) and a2) together with PS (3.3 wt.-%), PA6 (0.8 wt.-%), talc (0.5 wt.-%), chalk (0.5 wt.-%) and small amounts of other substances (the MFR2 (190°C) of the Dipolen S used was 3.2 g / 10 min and the MFR2 (230°C) was 5.3 g / 10 min) was 100 wt.-%.

[0241] Component B)

[0242] EMA is ethylene methyl acrylate (MFR2 (190° C.) = 0.5 g / 10 min, MA content = 25 wt.-% based on the total weight of the polymer), commercially available under the trade name Elvaloy AC1125 from Dow / DuPont.

[0243] EBA1 is ethylene butyl acrylate (MFR2 (190° C.)=0.85 g / 10 min, BA content=17 wt.-%, based on the total weight of the polymer) and was prepared as follows.

[0244] Fresh ethylene and recycled ethyl acrylate and comonomer butyl ester were compressed in two parallel streams to an initial reactor pressure of 2500 bar, providing L / Ds varying between approximately 17,300 and 30,400 to the front and side of the split feed 2 reactor. Comonomer was added in an amount to achieve 17 wt.% in the final polymer. The MFR2 of the final polymer was maintained at 0.85 g / 10 min. After compression, the front stream was heated to 151°C in a preheating section before entering the front section of the reactor, and the side stream was cooled and allowed to enter the side of the reactor. A mixture of commercially available peroxide free radical initiators dissolved in a substantially inert hydrocarbon solvent was injected after the preheating section and at one or more locations along the reactor in an amount sufficient to achieve exothermic polymerization reactions reaching peak temperatures of 275°C and 260°C, respectively, with cooling to 170°C between. The reaction mixture was depressurized via a pressure control valve, cooled, and the polymer separated from unreacted gases.

[0245] EBA2 is ethylene butyl acrylate (EBA, MFR2 (190° C.)=4.5 g / 10 min, BA content=27 wt.-%, based on the total weight of the polymer), which was prepared as follows.

[0246] Fresh ethylene and recycled ethyl acrylate and comonomer butyl ester were compressed in two parallel streams to an initial reactor pressure of 2500 bar, providing L / Ds varying between approximately 17,300 and 30,400 to the front and side of the split feed zone 2 reactor. Comonomer was added in an amount to achieve 27 wt.% in the final polymer. The MFR2 of the final polymer was maintained at 4.5 g / 10 min. After compression, the front stream was heated to 160°C in a preheating section before entering the front section of the reactor, and the side stream was cooled and allowed to enter the side of the reactor. A mixture of commercially available peroxide free radical initiators dissolved in a substantially inert hydrocarbon solvent was injected after the preheating section and at one or more locations along the reactor in an amount sufficient to achieve exothermic polymerization reaction peak temperatures of 275°C and 275°C, respectively, with cooling to 165°C between. The reaction mixture was depressurized via a pressure control valve, cooled, and the polymer separated from unreacted gases.

[0247] AO is a mixture of commercial antioxidants, primarily containing Irganox B 225 (FF) commercially available from BASF (CH).

[0248] C. Experimental Results

[0249] Polymer compositions (IE1 to IE15) according to the inventive examples and comparative examples (CE1 to CE4) were prepared on a Coperion ZSK24 with an L / D ratio of 40. Mixing temperatures of 190°C to 235°C were used during mixing, and the molten strands were solidified in a water bath before being pelletized. The amounts of the various components in the polymer compositions according to the inventive examples and comparative examples and the properties of the polymer compositions can be gathered from Tables 3 to 6 below.

[0250] Table 3: Polymer compositions including EMA and their properties.

[0251]

[0252] The polymer compositions shown in Table 3 above all contain the same type of recyclate (Purpolen PP). The polymer composition according to CE1 consists of this recyclate and an antioxidant mixture. In addition, IE1 contains 5 wt.% EMA, and the EMA content of IE2 and IE3 is increased to 10 wt.% and 20 wt.%, respectively. As shown in Table 3, the toughness of the polymer composition (represented by Charpy notched impact strength and tensile strain at break at 23°C) increases with increasing EMA content. After adding 5 wt.% EMA, a small increase in Charpy notched impact strength and a significant increase in tensile strain are already observed, with higher amounts being used to obtain recyclate-based polymer compositions with significantly increased Charpy notched impact strength and tensile strain at break.

[0253] Table 4: Polymer compositions including EMA and their properties.

[0254]

[0255] The polymer compositions shown in Table 4 above all contain the same type of recyclate (Dipolen S). The polymer composition according to CE2 consists of this recyclate and an antioxidant mixture. In addition, IE4 contains 5 wt.-% EMA, and for IE5 and IE6, the EMA content is increased to 10 wt.-% and 20 wt.-%, respectively. As can be seen in Table 4, the toughness of the polymer composition (represented by Charpy notched impact strength and tensile strain at 23°C) increases with increasing EMA content. After adding 5 wt.-% EMA, a significant increase in Charpy notched impact strength and tensile strength is observed, with higher amounts being added to obtain recyclate-based polymer compositions with excellent Charpy notched impact strength and tensile strain.

[0256] Table 5: Polymer compositions including EBA and their properties.

[0257]

[0258] The polymer compositions shown in Table 5 above all contain the same type of recyclate (Purpolen PP). The polymer composition according to CE3 consists of this recyclate and an antioxidant mixture. In addition, IE7 contains 5 wt.% EBA, and for IE8 and IE9, the EBA content is increased to 100 wt.% and 20 wt.%, respectively. As can be seen from Table 5, the toughness of the polymer composition (represented by the Charpy notched impact strength and tensile strain at 23°C) increases with increasing EBA content. After adding 5 wt.% EBA, a small increase in the Charpy notched impact strength and a significant increase in the tensile strain at break are already observed, with higher amounts being used to obtain polymer compositions based on recyclate having significantly increased Charpy notched impact strength and tensile strain at break.

[0259] Table 6: Polymer compositions including EBA and their properties.

[0260]

[0261]

[0262] The polymer compositions shown in Table 6 above all contain the same type of recyclate (Dipolen S). The polymer composition according to CE4 consists of this recyclate and an antioxidant mixture. In addition, IE10 and IE13 contain 5 wt.% EBA, and the EBA content is increased to 10 wt.% and 20 wt.% for IE11, IE12, IE14 and IE15, respectively. As shown in Table 6, the toughness of the polymer compositions (represented by Charpy notched impact strength and tensile strain at break at 23°C) increases with increasing EBA content. A significant increase in Charpy notched impact strength and tensile strength is observed after adding 5 wt.% EBA, with higher amounts being added to obtain recyclate-based polymer compositions with excellent Charpy notched impact strength and tensile strain at break.

Claims

1. A polymer composition comprising at least the following components A) 75 wt.-% to 95.5 wt.-%, based on the total weight of the polymer composition, of a polymer blend comprising a1) Polypropylene; a2) Polyethylene; in, The weight ratio of a1) to a2) is from 3:7 to 9:1; and wherein the polymer blend A) is a recycled material; B) 4.5 wt.-% to 25 wt.-%, based on the total weight of the polymer composition, of a virgin ethylene alkyl (meth)acrylate having the following properties An MFR2 at 190°C, 2.16 kg of 0.1 g / 10 min to 15 g / 10 min, as measured according to ISO 1133; and an alkyl (meth)acrylate content of 5 wt.-% to 40 wt.-%, based on the total weight of component B); The proviso is that the weight proportions of components A) and B) add up to 100 wt.-%.

2. The polymer composition according to claim 1, wherein Component A) comprises from 80.0 wt.-% to 99.9 wt.-% of polypropylene a1) and polyethylene a2), based on the total weight of component A); and / or Component A) comprises less than 5 wt.-%, based on the total weight of component A), of thermoplastic polymers different from a1) and a2); and / or Component A) comprises less than 5 wt.-% talc, based on the total weight of component A); and / or Component A) comprises less than 4 wt.-% chalk, based on the total weight of component A); and / or Component A) comprises less than 1 wt.-% paper, based on the total weight of component A).

3. The polymer composition according to claim 1 or 2, characterized in that Component A) comprises less than 1 wt.-% of wood, based on the total weight of component A); and / or Component A) comprises less than 1 wt.-% of metals, based on the total weight of component A); and / or Component A) comprises less than 100 ppm of limonene, based on the total weight of component A); and / or Component A) comprises less than 200 ppm of fatty acids, based on the total weight of component A); and / or Component A) is recycled material recovered from waste plastic material from post-consumer and / or post-industrial waste; and / or Component A has an MFR2 at 230° C., 2.16 kg, measured according to ISO 1133, of 2 g / 10 min to 50 g / 10 min.

4. The polymer composition according to claim 1, characterized in that Component B) is an ethylene alkyl acrylate.

5. The polymer composition according to claim 4, wherein Component B) is ethylene methyl acrylate, which has an MFR2 at 190°C, 2.16 kg, measured according to ISO 1133 of 0.1 g / 10 min to 10 g / 10 min; and / or A methyl acrylate content of 10 wt.-% to 35 wt.-%, based on the total weight of component B).

6. The polymer composition according to claim 4, wherein Component B) is ethylene butyl acrylate, which has an MFR2 at 190°C, 2.16 kg, measured according to ISO 1133 of 0.1 g / 10 min to 10 g / 10 min; and / or A butyl acrylate content of 10 wt.-% to 40 wt.-%, based on the total weight of component B).

7. The polymer composition according to claim 1, wherein The polymer composition has an MFR2 at 230°C, 2.16 kg, measured according to ISO 1133 of 0.5 g / 10 min to 40 g / 10 min; and / or 10% to 750% of the tensile strain at break measured according to ISO 527-2; and / or Greater than 2.0 kJ / m 2 Charpy notched impact strength measured at 23°C according to ISO 179-1eA.

8. The polymer composition according to claim 1, wherein Component B) is ethylene methyl acrylate, and the polymer composition has a tensile strain at break measured according to ISO 527-2 that is at least 10% higher than the same polymer composition without component B); and / or a Charpy notched impact strength measured according to ISO 179-1eA at 23°C of at least 2% higher than that of the same polymer composition without component B; or Component B) is ethylene butyl acrylate, and the polymer composition has a tensile strain at break measured according to ISO 527-2 that is at least 10% higher than the same polymer composition without component B); and / or A Charpy notched impact strength, measured according to ISO 179-1eA at 23°C, that is at least 2% higher than the same polymer composition without component B).

9. The polymer composition according to claim 1, wherein The content of component A) in the polymer composition is from 76 wt.-% to 95.1 wt.-%, based on the total weight of the polymer composition; and / or The content of component B) in the polymer composition is from 4.9 wt.-% to 24 wt.-%, based on the total weight of the polymer composition; and / or The content of polypropylene a1) in component A) is from 75 wt.-% to 98 wt.-%, based on the total weight of component A), or The content of polypropylene a1) in component A) is from 25 wt.-% to 85 wt.-%, based on the total weight of component A); and / or The content of polyethylene a2) in component A) is from 5 wt.-% to 25 wt.-%, based on the total weight of component A); or The content of polyethylene a2) in component A) is from 15 wt.-% to 75 wt.-%, based on the total weight of component A).

10. The polymer composition according to claim 1, characterized in that The polymer composition comprises at least one additive selected from the group consisting of slip agents, UV stabilizers, pigments, antioxidants, antiblocking agents, antistatic agents, antacids, additive carriers, nucleating agents, and mixtures thereof, wherein the additive is present in an amount of 0 wt.-% to 5 wt.-%, based on the total weight of the polymer composition.

11. The polymer composition according to claim 1, wherein The polymer composition comprises at least the following components A) 80 wt.-% to 95 wt.-%, based on the total weight of the polymer composition, of a polymer blend comprising a1) Polypropylene; a2) Polyethylene; wherein the weight ratio of a1) to a2) is from 3:7 to 9:1; and wherein the polymer blend A) is a recycled material; B) 5 wt.-% to 20 wt.-%, based on the total weight of the polymer composition, of a virgin ethylene alkyl acrylate having the following properties an MFR2 at 190°C, 2.16 kg of from 0.1 g / 10 min to 10 g / 10 min, as measured according to ISO 1133; and an alkyl acrylate content of 5 wt.-% to 40 wt.-%, based on the total weight of component B); The proviso is that the weight proportions of components A) and B) add up to 100 wt.-%.

12. A method for preparing a polymer composition according to any one of claims 1 to 11, comprising the following steps: i) providing 75.5 wt.-% to 95.5 wt.-% of a polymer blend A) comprising recycled materials of a1) polypropylene and a2) polyethylene, based on the total weight of the polymer composition, wherein the weight ratio of a1) to a2) is from 3:7 to 9:1; ii) providing a raw ethylene alkyl (meth)acrylate B) having the following properties an MFR2 at 190°C, 2.16 kg of 0.1 g / 10 min to 15 g / 10 min, measured according to ISO 1133; and an alkyl (meth)acrylate content of 5 wt.-% to 40 wt.-%, based on the total weight of component B); iii) melting and mixing components A) and B) to obtain said polymer composition; and iv) Optionally, cooling the polymer composition obtained in step iii) and / or pelletizing the polymer composition.

13. The method according to claim 12, wherein Component B) is ethylene methyl acrylate, which has an MFR2 at 190°C, 2.16 kg, measured according to ISO 1133 of 0.1 g / 10 min to 10 g / 10 min; and / or a methyl acrylate content of 10 to 35 wt.-%, based on the total weight of component B); or Component B) is ethylene butyl acrylate having an MFR2 at 190°C, 2.16 kg, measured according to ISO 1133 of 0.1 g / 10 min to 10 g / 10 min; and / or A butyl acrylate content of 10 wt.-% to 40 wt.-%, based on the total weight of component B).

14. Use of a raw ethylene alkyl (meth)acrylate B) having the following properties an MFR2 at 190°C, 2.16 kg of 0.1 g / 10 min to 15 g / 10 min, measured according to ISO 1133; and an alkyl (meth)acrylate content of 5 wt.-% to 40 wt.-%, based on the total weight of component B); Polymer blends for increasing recycled content A) said tensile strain at break measured according to ISO 527-2; and / or Charpy notched impact strength measured according to ISO 179-1eA at 23°C The polymer blend A) of recycled materials comprises a1) polypropylene and a2) polyethylene, wherein The weight ratio of a1) to a2) is 3:7 to 9:1; Thereby, the pristine ethylene alkyl (meth)acrylate B) is present in an amount of 4.5 wt.-% to 25 wt.-%, based on the total weight of components A) and B).

15. An article comprising the polymer composition of any one of claims 1-11.

Images