Improving the impact resistance of recycled polymers

Abstract

Improving the impact resistance of recycled polymers. The present invention relates to a composition comprising: - a recycled polymer, and - an impact-modifying additive. Figure for abstract: None

Description

Title of the invention: Improvement of the impact resistance of recycled polymers

[0001] The present invention relates to a recycled polymer composition. The present invention also relates to a method for preparing such a composition. The present invention further relates to a method for improving the impact resistance of a recycled polymer.

[0002] Plastic products are generally formed from virgin plastics (also called native materials). However, societal expectations regarding environmental protection and reduced resource consumption are increasingly strong, and it is therefore necessary to develop new materials obtained from recycled materials, in particular from recycled polymers.

[0003] The disadvantage of using a recycled polymer is that its performance is generally degraded compared to that of the corresponding virgin polymer, particularly its impact resistance. Furthermore, the future use of the recycled polymer is not necessarily identical to its past use, which implies that the properties of the recycled polymer must be modified / adapted for this new use.

[0004] There is therefore a need for recycled polymer materials with good performance, particularly mechanical, similar to or superior to the performance of the corresponding native polymer materials.

[0005] In particular, there is a need for recycled polymer materials possibly comprising at least one additive and exhibiting good impact resistance performance.

[0006] In particular, an objective of the present invention is to provide a recycled acrylonitrile-butadiene-styrene polymer composition, optionally with additives, having an IZOD notched impact resistance value at 23°C (ISO 180 standard of 2019) greater than or equal to 8 kJ / m2.

[0007] Another particular objective of the invention is to provide a composition of recycled polystyrene, optionally with additives, having an IZOD notched impact resistance value at 23 °C greater than or equal to 5 kJ / m2.

[0008] There is also a need for a method of determining recycled polymer compositions suitable for use in a predefined application, in particular the manufacture of a specific object. In particular, there is a need for a method of determining the nature and / or content of an additive to be added to a composition of recycled polymer, to obtain a final composition comprising a recycled and additively enhanced polymer suitable for use in a predefined application.

[0009] In particular, there is a need for a process for determining recycled polymer compositions suitable for use in a predefined use in which impact resistance is an important criterion.

[0010] The present invention therefore relates to a composition comprising:

[0011] - a recycled polymer, and

[0012] - an impact modifying additive.

[0013] The inventors discovered that a recycled polymer could exhibit impact resistance similar to or even greater than the impact resistance of the corresponding native polymer by adding at least one impact modifying additive.

[0014] The inventors also discovered, surprisingly, that a recycled polymer treated with an additive other than an impact modifier has reduced impact resistance compared to the recycled polymer alone, but that it is possible to increase this impact resistance by adding an impact modifier. It is thus possible to obtain recycled polymer materials with properties comparable to those of the corresponding native polymers, and which can be used in the manufacture of new objects. Recycled polymer

[0015] According to ISO 472 of 2013, recycled plastic is plastic obtained by transformation in a production process of plastic waste for the purposes of its original function or for other purposes, with the exception of energy recovery.

[0016] More precisely, for the purposes of this invention, a recycled polymer is understood to mean a post-consumer polymer, that is, one that has already served its intended purpose, for example, in the manufacture of a consumer product, and which would otherwise be discarded as waste. In contrast, a virgin (or native) polymer is a polymer obtained through a polymerization process that prepares it from one or more monomers. There are also post-industrial polymers, which refer to plastic waste generated by manufacturers of the consumer products mentioned above. Finally, post-production polymers are waste generated by producers of plastic materials. The thermomechanical properties of post-production polymers are much closer to those of virgin polymers than to those of post-consumer or post-industrial polymers.Indeed, a post-consumer polymer has been subjected to shocks and / or temperature variations and / or UV radiation, and its thermomechanical properties are diminished compared to those of a virgin polymer or those of a post-production polymer. A post-industrial polymer also exhibits modified properties compared to a virgin polymer insofar as it has undergone trans- steps. training.

[0017] A recycled polymer according to the invention is a post-consumer polymer or a post-industrial polymer, preferably post-consumer.

[0018] Preferably, the composition according to the invention is characterized by an IZOD impact resistance of a value greater than or equal to 6.0 kJ / m2, preferably greater than or equal to 8.0 kJ / m2, more preferably greater than or equal to 9.8 kJ / m2, more preferably between 6.0 and 16 kJ / m2, advantageously between 9.8 and 14 kJ / m2.

[0019] Throughout the description, "IZOD impact resistance" means "IZOD impact resistance notched at 23°C" and is determined according to ISO 180:2019.

[0020] Preferably, the composition according to the invention has a rate of increase in impact resistance greater than or equal to 1.1, preferably greater than or equal to 1.2, preferably greater than or equal to 1.5, more preferably greater than or equal to 1.8, even more preferably greater than or equal to 2, advantageously greater than or equal to 2.5, the rate of increase in impact resistance being the ratio between the IZOD impact resistance value of the composition according to the invention and the IZOD impact resistance value of a composition differing from the composition according to the invention only in that it is devoid of the impact modifying additive.

[0021] Preferably, the rate of increase in the impact resistance of the composition according to the invention goes from 1.1 to 3, preferably from 1.5 to 2.5, preferably from 1.8 to 2.

[0022] Preferably, in the composition according to the invention, the weight content of recycled polymer varies from 60% to 98% by weight, preferably from 70% to 95% by weight, preferably from 80% to 92% by weight, advantageously from 85% to 90% by weight relative to the total weight of the composition.

[0023] Preferably, the recycled polymer is chosen from recycled polystyrenes, recycled acrylonitrile-butadiene-styrene polymers, and any of their mixtures.

[0024] Typically, a recycled (or post-consumer) acrylonitrile-butadiene-styrene polymer may have an IZOD impact resistance value of less than or equal to 12 kJ / m2, preferably less than or equal to 9 kJ / m2, preferably ranging from 6 to 12 kJ / m2, preferably ranging from 6.5 to 9 kJ / m2.

[0025] Typically, recycled (or post-consumer) polystyrene may have an IZOD impact resistance value less than or equal to 10 kJ / m2, preferably less than or equal to 8 kJ / m2, preferably ranging from 3 to 10 kJ / m2, preferably ranging from 4.5 to 7 kJ / m2.

[0026] According to a first embodiment, the recycled polymer is a recycled acrylonitrile-butadiene-styrene polymer.

[0027] The recycled acrylonitrile-butadiene-styrene polymer can be a mixture consisting of recycled acrylonitrile-butadiene-styrene, less than 8% by weight of recycled polystyrene, preferably less than 3% by weight, and less than 5% by weight of recycled polypropylene, preferably less than 2% by weight, relative to the total weight of the recycled polymer.

[0028] According to this embodiment, the composition according to the invention is preferably characterized by an IZOD impact resistance of a value greater than or equal to 8.0 kJ / m2, preferably greater than or equal to 10.0 kJ / m2, more preferably greater than or equal to 12.0 kJ / m2, more preferably between 8.0 and 20.0 kJ / m2, advantageously between 10.0 and 16.0 kJ / m2.

[0029] According to a second embodiment, the recycled polymer is recycled polystyrene.

[0030] Recycled polystyrene can be a mixture consisting of recycled polystyrene, less than 8% by weight of recycled acrylonitrile-butadiene-styrene polymer, preferably less than 5% by weight, and less than 5% by weight of recycled polypropylene, preferably less than 2% by weight, relative to the total weight of the recycled polymer.

[0031] According to this embodiment, the composition according to the invention is preferably characterized by an IZOD impact resistance of a value greater than or equal to 5.0 kJ / m2, preferably greater than or equal to 6.0 kJ / m, preferably greater than or equal to 8.0 kJ / m2, more preferably greater than or equal to 10.0 kJ / m2, more preferably between 6.0 and 20.0 kJ / m2, advantageously between 8.0 and 18.0 kJ / m2. Impact modifier additive

[0032] The composition according to the invention comprises at least one impact modifier additive.

[0033] An impact modifier additive is a chemical compound which, when mixed with a polymer, makes the polymer more impact-resistant. In particular, an impact modifier additive is a polymeric material that improves the impact properties of a polymer, for example, the IZOD notch impact resistance at 23°C, as determined according to ISO 180 (2019 version). This term is also known as "impact modifiers," "impact additives," or "impact modifiers." This term is well known to those skilled in the art.

[0034] Preferably, according to the invention, an impact modifying additive is an additive which enables a polymer comprising 5% by weight of this additive, relative to the total weight of polymer-additive mixture, to exhibit a rate of increase in its impact resistance greater than or equal to 1.2, preferably greater than or equal to 1.5, more preferably greater than or equal to 2.0.

[0035] Thus, preferably, the impact modifier additive makes it possible to increase by at least 10% IZOD impact resistance of a composition consisting of the recycled polymer and 5% by weight of said impact modifier additive.

[0036] Examples of suitable impact-modifying additives include, for example, grafted polymers, core-shell polymers, and sequenced copolymers. These polymers can be obtained from at least one monomer selected from the group consisting of an alkene, an alkadiene, an arene, and an acrylate.

[0037] Preferably, the impact modifying additive is a copolymer obtained from at least one vinyl monomer.

[0038] By copolymer, we mean a polymer resulting from the copolymerization of at least two or more types of chemically different monomers, called comonomers.

[0039] By vinyl monomer, we mean an organic molecule comprising at least one carbon-carbon double bond. Preferably, the vinyl monomer has the following formula: CH2=CRR', with R and R' being independently chosen from the group consisting of a hydrogen atom, an aromatic group, preferably a phenyl, a hydrocarbon group comprising from 1 to 10 carbon atoms, preferably from 2 to 10 carbon atoms, saturated or unsaturated, further optionally comprising an ester group, a nitrile group, a carboxyl group, an amine group or an amide group.

[0040] Preferably, the impact modifying additive is a copolymer of ethylene and / or styrene, that is to say that at least one of the comonomers of the copolymer is chosen from styrene and ethylene.

[0041] Preferably, the impact modifying additive comprises a copolymer resulting from the copolymerization of at least two monomers selected from the group consisting of a C2-C8 alkene, a C4-C8 diene, a styrenic monomer and an acrylic monomer.

[0042] Preferably, the impact modifying additive comprises a copolymer resulting from the copolymerization of at least two monomers selected from the group consisting of ethylene, butene, styrene, butadiene, acrylonitrile, (m)ethyl (meth)acrylate and butyl (meth)acrylate.

[0043] In some embodiments, the impact-modifying additive is functionalized or grafted. The functionalized or grafted ethylene copolymer may comprise polar compounds, including, for example, an anhydride or epoxy function, preferably cyclic, preferably maleic anhydride or glycidyl (meth)acrylate.

[0044] Preferably, the impact modifier additive is chosen from:

[0045] - copolymers of ethylene and / or butene and a polar monomer selected from (m)ethyl acrylate, (m)ethyl methacrylate and (meth)butyl acrylate,

[0046] - modified acrylonitrile-butadiene-styrene copolymers having a level of butadiene greater than or equal to 60% by weight relative to the total weight of the modified acrylonitrile-butadiene-styrene polymer,

[0047] - styrene-ethylene / butene-styrene copolymers grafted with anhydride maleic acid or glycidyl methacrylate,

[0048] - ethylene-butyl acrylate copolymers, possibly grafted by maleic anhydride,

[0049] - styrene-butadiene copolymers, preferably styrene- Block butadiene, preferably multiblock or diblock styrene-butadiene copolymers,

[0050] - styrene-ethylene / butene-styrene copolymers, preferably copolymers styrene-ethylene / butene-styrene block,

[0051] and

[0052] - any one of their mixtures.

[0053] Advantageously, the impact modifying additive is a copolymer of ethylene and / or butene and a polar monomer selected from (m)ethyl acrylate, (m)ethyl methacrylate and butyl (meth)acrylate, more advantageously a copolymer of ethylene and a polar monomer selected from (m)ethyl acrylate and (m)ethyl methacrylate.

[0054] (M)ethyl means methyl or ethyl group.

[0055] (Meth)acrylate means acrylate or methacrylate.

[0056] Preferably, the copolymer of ethylene and / or butene and a polar monomer selected from (m)ethyl acrylate, (m)ethyl methacrylate, and (meth)butyl acrylate is a random copolymer. Such a copolymer can be prepared under high pressure from a mixture of ethylene and / or butene and at least one polar monomer selected from (m)ethyl acrylate, (m)ethyl methacrylate, and (meth)butyl acrylate in the presence of a radical polymerization initiator.

[0057] The copolymer of ethylene and / or butene and a polar monomer selected from (m)ethyl acrylate, (m)ethyl methacrylate and butyl (meth)acrylate preferably comprises 10% to 40% by weight, preferably 15% to 35% by weight, preferably still 26% to 32% by weight of polar monomer relative to the total weight of the copolymer, and 60% to 90% by weight of ethylene and / or butene, preferably 65% ​​to 85% by weight, preferably still 68% to 74% by weight relative to the total weight of the copolymer.

[0058] Preferably, the impact modifying additive comprises a copolymer of ethylene and methyl acrylate.

[0059] By way of example of a copolymer of ethylene and / or butene and a polar monomer selected from (m)ethyl acrylate, (m)ethyl methacrylate and (meth)butyl acrylate, ethylene / methylacrylate copolymers may be cited commercial products available under the reference Lotryl ©29MA03T, from SK Functional Polymer, Elvaloy® copolymers (AC1125, AC12024 S, AC1330) from Dow, or EMAC® SP2260, EMAC® SP2403, EMAC® SP2268 products from Westlake.

[0060] Preferably, the modified acrylonitrile-butadiene-styrene polymer has a butadiene content of 60% to 80%, preferably 60% to 65%.

[0061] As an example of a modified acrylonitrile-butadiene-styrene polymer having a butadiene content greater than or equal to 60% by weight, we can cite the product referenced KUMHO® HR 181 from the company Korea Kumho Petrochemical.

[0062] As an example of a styrene-ethylene / butene-styrene copolymer functionalized by For maleic anhydride, we can mention the product referenced SEBS-g-MA® from the company Kraton Polymer.

[0063] As an example of styrene-ethylene / butene-styrene copolymers grafted with maleic anhydride, we can cite the product referenced C1010® from the company Kraton Polymer.

[0064] As an example of styrene-ethylene / butene-styrene copolymers grafted with glycidyl methacrylate, we can cite the product referenced 02520 C® from the company Graft polymer.

[0065] As an example of ethylene-butyl acrylate copolymers, we can cite the product Lucofin® 1400PN from the company Lucobit.

[0066] As an example of maleic anhydride grafted ethylene-butyl acrylate copolymers, we can cite the product Lucofin® 1492 MGH from the company Lucobit.

[0067] As an example of a styrene-butadiene copolymer, we can cite the product referenced SBS-C3000® from the company Kraton Polymer or the product referenced DENKA NSBC® from the company DENKA.

[0068] As an example of a styrene-ethylene / butene-styrene copolymer, we can cite the product referenced SBS-C2000® from the company Kraton Polymer.

[0069] Preferably, the weight content of impact modifier additive varies from 0.5% to 20% by weight, preferably from 1% to 18% by weight, preferably from 1% to 16% by weight, preferably from 2% to 13% by weight, preferably from 3% to 10% by weight, advantageously from 4% to 8% by weight relative to the total weight of the composition.

[0070] If the composition includes a mixture of at least two impact modifying additives, the above weight content defines the sum of the weight content of each impact modifying additive.

[0071] According to one embodiment, the impact modifier additive comprises a mixture of:

[0072] - a copolymer of ethylene and / or butene and a polar monomer selected from (m)ethyl acrylate, (m)ethyl methacrylate and butyl (meth)acrylate, and

[0073] - a modified acrylonitrile-butadiene-styrene polymer having a level of butadiene greater than or equal to 60% by weight relative to the total weight of the modified acrylonitrile-butadiene-styrene polymer.

[0074] According to this embodiment, the content of ethylene and / or butene copolymer and a polar monomer selected from (m)ethyl acrylate, (m)ethyl methacrylate and butyl (meth)acrylate varies preferably from 1% to 15% by weight, preferably from 2% to 12% by weight, preferably from 3% to 10% by weight, more preferably from 4% to 8%, more preferably from 4% to 6% by weight relative to the total weight of the composition.

[0075] According to this embodiment, the content of modified acrylonitrile-butadiene-styrene polymer having a butadiene content greater than or equal to 60% by weight relative to the total weight of the modified acrylonitrile-butadiene-styrene polymer varies preferably from 2% to 30% by weight, preferably from 4% to 24% by weight, preferably from 6% to 20% by weight, more preferably from 8% to 16%, more preferably from 8% to 12% by weight relative to the total weight of the composition.

[0076] According to this embodiment, the weight ratio between the weight of ethylene and / or butene copolymer and a polar monomer selected from (m)ethyl acrylate, (m)ethyl methacrylate and butyl (meth)acrylate and the weight of modified acrylonitrile-butadiene-styrene polymer having a butadiene content greater than or equal to 60% by weight relative to the total weight of the modified acrylonitrile-butadiene-styrene polymer is preferably greater than or equal to 1, preferably from 1 to 10, preferably from 1.5 to 5, advantageously from 2 to 3.

[0077] According to this embodiment, the total weight content of impact modifier additive preferably ranges from 5% to 30%, relative to the total weight of the composition, preferably ranges from 8% to 18% by weight, advantageously ranges from 10% to 15% by weight.

[0078] According to another embodiment, the impact modifier additive comprises a mixture of:

[0079] - a modified acrylonitrile-butadiene-styrene polymer having a level of butadiene greater than or equal to 60% by weight relative to the total weight of the modified acrylonitrile-butadiene-styrene polymer, and

[0080] - a styrene-ethylene / butene-styrene copolymer grafted with maleic anhydride.

[0081] According to this embodiment, the content of the modified acrylonitrile-butadiene-styrene polymer having a butadiene content greater than or equal to 60% by weight relative to the total weight of the modified acrylonitrile-butadiene-styrene polymer varies preferably from 1% to 15% by weight, preferably from 2% to 10% by weight, preferably from 3% to 8% by weight relative to the total weight of the composition. According to this embodiment lisation, the content of styrene-ethylene / butene-styrene copolymer grafted with maleic anhydride varies preferably from 1% to 15% by weight, preferably from 2% to 10% by weight, preferably from 3% to 8% by weight relative to the total weight of the composition.

[0082] According to another embodiment, the impact modifier additive comprises a mixture of:

[0083] - a copolymer of ethylene and / or butene and a polar monomer selected from (m)ethyl acrylate, (m)ethyl methacrylate and (meth)butyl acrylate,

[0084] - a modified acrylonitrile-butadiene-styrene polymer having a level of butadiene greater than or equal to 60% by weight relative to the total weight of the modified acrylonitrile-butadiene-styrene polymer, and

[0085] - a styrene-ethylene / butene-styrene copolymer grafted with maleic anhydride.

[0086] According to this embodiment, the content of ethylene and / or butene copolymer and a polar monomer selected from (m)ethyl acrylate, (m)ethyl methacrylate and butyl (meth)acrylate varies preferably from 1% to 15% by weight, preferably from 2% to 10% by weight, preferably from 3% to 8% by weight relative to the total weight of the composition and / or the content of modified acrylonitrile-butadiene-styrene polymer having a butadiene content greater than or equal to 60% by weight relative to the total weight of the modified acrylonitrile-butadiene-styrene polymer varies preferably from 1% to 15% by weight, preferably from 2% to 10% by weight, preferably from 3% to 8% by weight relative to the total weight of the composition and / or the content of styrene-ethylene / butene-styrene copolymer grafted with maleic anhydride, preferably from 1% to 15% by weight, preferably from 2% to 10% by weight.preferably 3% to 8% by weight relative to the total weight of the composition.

[0087] According to another embodiment, the impact modifier additive comprises a mixture of:

[0088] - a copolymer of ethylene and / or butene and a polar monomer selected from (m)ethyl acrylate, (m)ethyl methacrylate and (meth)butyl acrylate,

[0089] - a modified acrylonitrile-butadiene-styrene polymer having a level of butadiene greater than or equal to 60% by weight relative to the total weight of the modified acrylonitrile-butadiene-styrene polymer, and

[0090] - a styrene-butadiene copolymer.

[0091] According to this embodiment, the content of ethylene and / or butene copolymer and a polar monomer selected from (m)ethyl acrylate, (m)ethyl methacrylate and butyl (meth)acrylate varies preferably from 1% to 10% by weight, preferably from 2% to 8% by weight, preferably from 3% to 7% by weight relative to the total weight of the composition and / or the acrylonitrile polymer content modified butadiene-styrene having a butadiene content greater than or equal to 60% by weight relative to the total weight of the modified acrylonitrile-butadiene-styrene polymer varies preferably from 2% to 20% by weight, preferably from 5% to 15% by weight, preferably from 8% to 12% by weight relative to the total weight of the composition and / or the styrene-butadiene copolymer content varies preferably from 1% to 10% by weight, preferably from 2% to 8% by weight, preferably from 3% to 7% by weight relative to the total weight of the composition.

[0092] These combinations of impact-modifying additives exhibit a synergistic effect with regard to improving the IZOD impact resistance of the composition. Second additive

[0093] Preferably, the composition according to the invention comprises a second additive different from the impact modifier additive.

[0094] Preferably, the second additive is different from a copolymer of ethylene and a polar monomer selected from (m)ethyl acrylate and (m)ethyl methacrylate.

[0095] More particularly, the second additive is different from an impact modifier as defined in this description. For example, the second additive is different from a polymer selected from the group consisting of an ethylene-methyl acrylate copolymer, a modified acrylonitrile-butadiene-styrene polymer having a butadiene content greater than or equal to 60% by weight relative to the total weight of the modified acrylonitrile-butadiene-styrene polymer, a styrene-ethylene / butene-styrene copolymer grafted with maleic anhydride, a styrene-butadiene copolymer, a styrene-ethylene / butene-styrene copolymer, an ethylene-butyl acrylate copolymer optionally grafted with maleic anhydride.

[0096] Preferably, the second additive is chosen from the group consisting of a UV stabilizer, a colorant, a curing accelerator, a lubricant, a flame retardant, a thermal polymerization inhibitor, a strengthening agent, a mineral filler, a diluent, a surfactant, a photosensitizer, a plasticizer, an antioxidant, a thermal resistance enhancer, a fluidizer, and any mixture thereof.

[0097] Preferably, the weight content of the second additive varies from 1% to 25% by weight, preferably from 2% to 20% by weight, preferably from 3% to 16% by weight, more preferably from 4% to 12% by weight, advantageously from 5% to 10% by weight relative to the total weight of the composition.

[0098] If the composition includes a mixture of at least two second additives, the above weight content defines the total weight content of second additives.

[0099] The present invention also relates to a method for preparing a composition according to the invention, comprising a step of mixing a recycled polymer and an impact modifying additive.

[0100] According to one embodiment, the recycled polymer is additively treated. A recycled polymer with additives comprises a recycled polymer and a second additive as defined in this description.

[0101] According to this embodiment, the preparation process comprises:

[0102] - a step of mixing a recycled polymer with a second additive, to obtain a recycled and additively enhanced polymer, and

[0103] - a step of adding a modifying additive to the recycled and additively treated polymer impact.

[0104] Alternatively, according to this embodiment, the preparation process includes a step of mixing a recycled polymer, an impact modifying additive and a second additive.

[0105] All the definitions, embodiments and preferred features described in the above description concerning the composition apply to all variants of the preparation process of the invention.

[0106] The present invention also relates to the use of an impact modifying additive in a composition comprising a recycled polymer to increase the impact resistance of said composition.

[0107] According to one embodiment, the composition further comprises a second additive different from the impact modifier additive.

[0108] All the definitions, embodiments and preferred characteristics described in the above description concerning the composition apply to all variants of this use.

[0109] The present invention also relates to a consumer product comprising a composition according to the invention.

[0110] The present invention further relates to a method for manufacturing a consumer product, comprising a step selected from extrusion, injection, molding, rotomolding, thermoforming and calendering of a composition according to the invention.

[0111] The present invention further relates to the use of a composition according to the invention, for the manufacture of a consumer product.

[0112] The determination of the composition described in this description is in particular facilitated by the implementation of a process for determining the nature and / or content of an additive to be added to a recycled polymer composition as described below.

[0113] The present invention therefore also relates to a method for determining the nature and / or content of an additive to be added to a recycled polymer composition to obtain a final composition comprising a recycled and additively treated polymer, suitable for use in a predefined application, in particular the manufacture of a specific object, including:

[0114] a) the determination of a first target range of values ​​required for a first physical quantity of the final composition to be used in the predefined use,

[0115] b) the measurement of the value of the first physical quantity for the recycled polymer composition,

[0116] c) the addition of an additive to the recycled polymer composition to obtain a recycled and additively treated polymer composition to be tested,

[0117] d) measuring the value of the first physical quantity of the recycled and additively treated polymer composition to be tested, in order to obtain a first measured value to be tested,

[0118] e) the test of a first criterion applied to the first measured value to be tested and to the first target interval, and

[0119] f) the selection of the additive if the first criterion is met, or

[0120] repeating steps c) to f) if the first criterion is not met.

[0121] Preferably, the additive is preferably an impact modifier additive or a second additive as defined above for the composition, in all the planned variants.

[0122] Preferably, the recycled polymer is preferably as defined above for composition, in all planned variants.

[0123] Preferably, the first physical quantity is the IZOD shock resistance.

[0124] According to one embodiment, the determination method is such that:

[0125] - step a) further comprises determining a second target interval of values ​​required for a second physical quantity of the final composition,

[0126] - step b) further includes measuring the value of the second quantity physical composition of recycled polymer

[0127] - step d) further comprises measuring the value of the second quantity physical composition of recycled and additively treated polymer to be tested, in order to obtain a second measured value to be tested.

[0128] - step e) further comprises testing a second criterion applied to the second measured value to be tested and at the second target interval, and

[0129] - step f) includes the selection of the additive if the first criterion and the second criteria are met, or

[0130] repeating steps c) to f) if the first criterion is not met and / or the second criterion is not met.

[0131] Preferably, the first physical quantity and, when present, the second physical quantity, are independently:

[0132] - a chemical property such as corrosion resistance,

[0133] - an electrical property such as conductivity, conductance, resistance, re sistivity or permittivity,

[0134] - a manufacturing property such as extrudability or hardness,

[0135] - an optical property such as color,

[0136] - a mechanical property such as IZOD impact resistance,

[0137] - a physical property such as flame retardancy, or

[0138] - a thermal or thermodynamic property such as the softening point Vicat.

[0139] Preferably, the additive is a combination of at least two distinct additives.

[0140] Preferably, the additive is a combination of an impact modifying additive and of at least one second additive as defined above for the composition, in all the planned variants.

[0141] According to a particular embodiment, the first physical quantity is the impact resistance IZOD, and:

[0142] - step a) includes determining a first required target interval of the re IZOD shock resistance of the final composition,

[0143] - step b) includes measuring the IZOD impact resistance value of the recycled polymer composition,

[0144] - step c) includes adding an additive to the recycled polymer composition for to obtain a composition of recycled and additively treated polymer for testing

[0145] - step d) includes measuring the IZOD impact resistance value of the composition of recycled and additively treated polymer to be tested, in order to obtain an IZOD impact resistance value to be tested.

[0146] - step e) includes testing a first criterion applied to the resistance value to the IZOD shock test and to the first target interval of the IZOD shock resistance, and

[0147] - step f) includes the selection of the additive if the first criterion is met, or

[0148] repeating steps c) to f) if the first criterion is not met.

[0149] According to another particular embodiment, the first physical quantity is the IZOD impact resistance of the final composition and the second physical quantity is a physical quantity of the final composition different from the IZOD impact resistance, and:

[0150] - step a) includes determining a first required target range of values of the IZOD shock resistance of the final composition and the determination of a second target range of values ​​required for the second physical quantity of the final composition,

[0151] - step b) includes measuring the IZOD impact resistance value of the composition of recycled polymer, and the measurement of the value of the second physical quantity for the composition of recycled polymer,

[0152] - step c) includes adding an additive to the recycled polymer composition for to obtain a composition of recycled and additively treated polymer for testing

[0153] - step d) includes measuring the IZOD impact resistance value of the composition of recycled and additive polymer to be tested to obtain a value of the IZOD impact resistance to be tested, and the measurement of the value of the second physical quantity of the composition of recycled and additive polymer to be tested to obtain a second measured value to be tested,

[0154] - step e) includes testing a first criterion applied to the resistance value to the IZOD shock to be tested and to the first target interval of the IZOD shock resistance, and the test of a second criterion applied to the second measured value to be tested and to the second target interval, and

[0155] - step f) is the selection of the additive if the first criterion and the second criterion are filled, or

[0156] repeating steps c) to f) if the first criterion is not met and / or the second criterion is not met.

[0157] Preferably, the second physical quantity is chosen from the Vicat softening point, color, flexural modulus, load bending temperature, fluidity index, ductility, flame retardancy, corrosion resistance and injectability.

[0158] Preferably, in embodiments in which the first physical quantity is the IZOD impact resistance, the additive is a combination of at least two distinct additives, of which at least one is an impact modifier additive.

[0159] Preferably, in embodiments in which the first physical quantity is the IZOD impact resistance, the required target range of the IZOD impact resistance is of the type [x ; +oo[, with x being a positive real number equal to 8.0 kJ / m2, preferably equal to 10.0 kJ / m2, more preferably equal to 12.0 kJ / m2.

[0160] Preferably, in all embodiments, the first criterion of the determination method according to the invention is the belonging of the first measured value to be tested to within 10% of the first target interval, preferably the belonging of the first measured value to be tested to the first target interval.

[0161] Preferably, in all embodiments, the recycled polymer is chosen from recycled polystyrenes, recycled acrylonitrile-butadiene-styrene polymers, and any of their mixtures.

[0162] The process for determining the nature and / or content of an additive to be added to a recycled polymer composition of the invention makes it possible to obtain a recycled polymer composition meeting the specifications imposed by a specific use.

[0163] The present invention therefore also relates to a composition intended to be used in a predefined use, in particular the manufacture of a specific object, comprising at least one recycled polymer and at least one additive determined according to the method for determining the nature and / or content of an additive to be added to a recycled polymer composition of the invention.

[0164] The present invention also relates to a method for preparing a composition intended for use in a specific application, in particular the manufacture of a specific object, comprising:

[0165] - the determination of the nature and / or content of an additive according to the process of determination of the nature and / or content of an additive to be added to a recycled polymer composition of the invention, and

[0166] - the mixture of a recycled polymer and the selected additive.

[0167] The present invention also relates to a device for determining at least one additive to be added to a recycled polymer composition to obtain a recycled and additively treated polymer composition suitable for use in a predetermined application, in particular the manufacture of a specific object, comprising:

[0168] - a device for mixing an additive and a recycled polymer composition to obtain a final composition of recycled and additively enhanced polymer, and

[0169] - a device for measuring the value of a first physical quantity of the communication position of recycled polymer and final composition of recycled and additive polymer.

[0170] Preferably, this device further comprises a measuring device for a second physical quantity of the composition of recycled polymer and of the final composition of recycled and additively treated polymer.

[0171] Preferably, the measuring device for the value of the first physical quantity of the recycled polymer composition and the final composition of the recycled and additively treated polymer is an IZOD impact resistance measuring device.

[0172] The present invention also relates to a system for preparing a recycled and additively enhanced polymer composition intended for use in a predefined application, the system comprising:

[0173] - an inflow of recycled polymer, in particular recycled polymer obtained by sorting waste, and

[0174] - an insertion unit for an additive in the recycled polymer.

[0175] All the definitions, embodiments, and preferred features described above concerning the composition or process apply to all variants of the method for determining the invention, to the composition intended for use in a predefined use of the invention, to the method for preparing a composition intended for use in a specific use of the invention, to the device of the invention, and to the preparation system. of a composition of the invention.

[0176] Throughout the description, the expression "from...to..." describes a range of values ​​whose bounds are included in this range.

[0177] The invention will now be described by means of the following non-limiting examples.

[0178] EXAMPLES

[0179] In all the following examples, the IZOD impact resistance was determined according to ISO 180 (2019 version).

[0180] Compositions marked with an asterisk are comparative.

[0181] Contents are indicated as a percentage by weight relative to the total weight of composition (% mass), unless otherwise stated.

[0182] Example 1: Improving the impact resistance of recycled ABS or PS

[0183] To prepare the compositions of this example, the recycled ground material is compounded by adding the impact modifier additive using metering hoppers.

[0184] In the compositions of this example, the following materials and additives were used:

[0185] ABS “lot EGR0064”

[0186] PS “lot EGR0072”

[0187] Impact modifier additive 1: ethylene and methyl acrylate copolymer (Lotryl 29MA03T®)

[0188] Impact modifier additive 2: a modified acrylonitrile-butadiene-styrene polymer having a butadiene content greater than or equal to 60% by weight relative to the total weight of the modified acrylonitrile-butadiene-styrene polymer (HR-181®)

[0189] Impact modifier additive 3: block styrene-butadiene copolymer (C3000®)

[0190] Impact modifier additive 4: styrene-butadiene-styrene triblock copolymer (SBS GI®

[0191] Impact modifier additive 5: block styrene-butadiene copolymer (SBS KTR 201®)

[0192] Impact modifier additive 6: styrene-ethylene / butene-styrene copolymer grafted with maleic anhydride (C1010®)

[0193] [Tables] Reference: Nature of recycled polymer; Nature of impact modifier additive; Impact modifier additive content (% by mass); IZOD notched at 23°C (kJ / m²); Cl₁* ABS - - 7.93 + 0.28 Cl₂ ABS 1 5% 14.7 + 0.3 Cl₂3 ABS 1 7% 16.80 + 0.58 Cl₂4 ABS 1 10% 18 + 0.5 Cl₂7 ABS 1 15% 19.8 + 0.4 Cl₂8 ABS 2 2% 10.60 + 0.27 Cl₂9 ABS 2 4% 14.20 + 0.44 Cl₂10 ABS 2 7% 14.70 + 0.59 Cl₂11 ABS 2 10% 15.3 + 0.39 Cl₂12 ABS 2 15% 19.1 + 0.9 Cl-21* PS - - 3.32 + 0.11 Cl-22 PS 3 5% 7.0 + 0.06 Cl-23 PS 4 (SBS GI) 5% 8.45 + 0.24 Cl-24 PS 5 (SBS KTR 201) 5% 8.2 + 0.13 Cl-25 PS 6 2.5% 3.6 + 0.1

[0194] * : comparative example

[0195] Example 2: Improving the impact resistance of recycled and additively treated ABS or PS

[0196] The compositions were prepared as follows:

[0197] Initially, the recycled shredded material is mechanically mixed with the second additive. During compounding, the second impact modifier additive is added using metering hoppers.

[0198] In the compositions of this example, the following materials and additives were used:

[0199] Impact modifier additive 1: ethylene methyl acrylate copolymer (Lotryl 29MA03T®)

[0200] Impact modifier additive 3: block styrene-butadiene copolymer (C3000®)

[0201] Impact modifier additive 5: block styrene-butadiene copolymer (SBS KTR 201®)

[0202] [Tables2] Reference Recycled Polymer Nature Impact Modifier Additive Nature (Wt. %) Second Additive (Wt. %) Notched IZOD 23°C (kJ / m²) C2-1 * PS "batch PGR0072" - - 5.9 + 0.19 C2-2 * PS "batch PGR0072" - 2% 4.99 + 0.14 C2-3 PS "batch PGR0072" 1 (1%) 2% 6.96 + 0.38 C2-4 PS "batch PGR0072" 1 (2%) 2% 6.94 + 0.90 C2-5 PS "batch PGR0072" 1 (3%) 2% 8.31 + 0.60 C2-6 PS "batch PGR0072" 1 (4%) 2% 9.72 + 1.19 C2-7 PS "batch PGR0072 » 1 (5%) 2% 9.99 + 0.39 C2-8 PS “lot PGR0072” 1 (6%) 2% 10.20 + 0.56 C2-9 PS “lot PGR0072” 1 (10%) 2% 12.20 + 0.39

[0203] “The second additive is chosen from the group consisting of a UV stabilizer, a colorant, a lubricant, a curing accelerator, a lubricant, a flame retardant, a thermal polymerization inhibitor, a strengthening agent, a mineral filler, a diluent, a surfactant, a photosensitizer, a plasticizer, an antioxidant and a flame retardant.

[0204] * : comparative example

[0205] [Tables3] Reference: Nature of recycled polymer, Impact modifier additive (% by mass), Second additive (% by mass), Notched IZOD 23°C (kJ / m²), C2-10* ABS "batch EGR0064" - - 10.90 + 0.37, C2-11* ABS "batch EGR0064" - 2% 10.20 + 0.31, C2-12 ABS "batch EGR0064" 1 (1%) 2% 11.70 + 0.38, C2-13 ABS "batch EGR0064" 1 (1%) - 12.80 + 0.32, C2-14 ABS "batch EGR0064" 1 (2%) 2% 12.70 + 0.58, C2-15 ABS "batch EGR0064" 1 (2%) - 13.40 + 0.47 C2-16 ABS “lot EGR0064” 1 (4%) 2% 14.0 + 0.68 C2-17 ABS “lot EGR0064” 1 (6%) 2% 14.80 + 0.78 C2-18 ABS “lot EGR0064” 1 (10%) 2% 16.50 + 1.14

[0206] a The second additive is chosen from the group consisting of a UV stabilizer, a colorant, a lubricant, a curing accelerator, a lubricant, a flame retardant, a thermal polymerization inhibitor, a strengthening agent, a mineral filler, a diluent, a surfactant, a photosensitizer, a plasticizer, an antioxidant and a flame retardant.

[0207] [Tables4] Reference Nature of recycled polymer Impact modifier additive (% by mass) Second additive (% by mass) Notched IZOD 23°C (kJ / m²) C2-20* PS "batch PGR0072" - - 3.3 C2-21* PS "batch PGR0072" - 5% 2.3 C2-22 PS "batch PGR0072" 3 (5%) - 7.0 + 0.1 C2-23 PS "batch PGR0072" 3 (5%) 5% 6.1 + 0.2 C2-24 PS "batch PGR0072" 5 (5%) - 8.2 + 0.1 C2-25 PS "batch PGR0072" 5 (5%) 5% 7.8 + 0.1

[0208] a The second additive is chosen from the group consisting of a UV stabilizer, a colorant, a lubricant, a curing accelerator, a lubricant, a flame retardant, a thermal polymerization inhibitor, a strengthening agent, a mineral filler, a diluent, a surfactant, a photosensitizer, a plasticizer, an antioxidant and a flame retardant.

[0209] * : comparative example

[0210] These results show that 1) the addition of the second additive further reduces the impact resistance of the recycled polymers, and 2) that the addition of an impact modifier additive significantly improves the impact resistance of these recycled and additive-enhanced polymers.

[0211] Example 3: Synergistic effect between at least two impact modifying additives according to the invention

[0212] To prepare the compositions of this example, the recycled ground material is compounded by adding the additive(s) chosen from the impact modifier additives using dosing hoppers.

[0213] In the compositions of this example, the following materials and additives were used:

[0214] ABS “lot EGR0064”

[0215] Impact modifier additive 1: ethylene-methyl acrylate copolymer (Lotryl 29MA03T®)

[0216] Impact modifier additive 2: a modified acrylonitrile-butadiene-styrene polymer having a butadiene content greater than or equal to 60% by weight relative to the total weight of the modified acrylonitrile-butadiene-styrene polymer (HR-181®)

[0217] [Tables5] Reference Nature of recycled polymer Impact modifier additive 1 (% by mass) Impact modifier additive 2 (% by mass) Notched IZOD 23°C (kJ / m²) C3-1* ABS - - 7.93 + 0.28 C3-2 ABS 15 - 19.8 + 0.5 C3-4 ABS - 15 19.1 + 0.9 C3-5 ABS 10 5 21.4 + 0.7

[0218] * : comparative example

[0219] For an equivalent amount of impact modifier additive, compositions comprising a mixture of two impact modifiers exhibit better shock resistance than compositions comprising only one impact modifier, which demonstrates a synergistic effect between these two impact modifier additives.

Claims

Demands

1. Composition comprising: - from 60% to 98% by weight, relative to the total weight of the composition, of a recycled polymer, and - an impact modifying additive selected from: - copolymers of ethylene and / or butene and a polar monomer selected from (m)ethyl acrylate, (m)ethyl methacrylate and butyl (meth)acrylate, - modified acrylonitrile-butadiene-styrene copolymers having a butadiene content greater than or equal to 60% by weight relative to the total weight of the modified acrylonitrile-butadiene-styrene polymer, - styrene-ethylene / butene-styrene copolymers grafted with maleic anhydride or glycidyl methacrylate, - ethylene-butyl acrylate copolymers, optionally grafted with maleic anhydride, - copolymers styrene-butadiene, preferably block styrene-butadiene copolymers, preferably multiblock or diblock styrene-butadiene copolymers, - styrene-ethylene / butene-styrene copolymers,preferably styrene-ethylene / butene-styrene block copolymers, and any mixture thereof.

2. Composition according to claim 1, wherein the impact modifier additive makes it possible to increase by at least 10% the IZOD impact resistance of a composition consisting of the recycled polymer and 5% by weight of said impact modifier additive, compared to the IZOD impact resistance of a composition differing from said composition in that it is devoid of the impact modifier additive.

3. Composition according to claim 1 or 2, wherein the impact modifying additive is a copolymer of ethylene and / or butene and a polar monomer selected from (m)ethyl acrylate, (m)ethyl methacrylate and butyl (meth)acrylate.

4. Composition according to claim 1 or 2, wherein the impact modifying additive comprises a mixture of: - a copolymer of ethylene and / or butene and a polar monomer selected from (m)ethyl acrylate, (m)ethyl methacrylate and butyl (meth)acrylate, and - a modified acrylonitrile-butadiene-styrene polymer having a butadiene content greater than or equal to 60% by weight relative to the total weight of the modified acrylonitrile-butadiene-styrene polymer.

5. Composition according to any one of the preceding claims, wherein the weight content of impact modifier additive varies from 0.5% to 20% by weight, preferably from 1% to 18% by weight, preferably from 1% to 16% by weight, preferably from 2% to 13% by weight, preferably from 3% to 10% by weight, advantageously from 4% to 8% by weight relative to the total weight of the composition.

6. Composition according to any one of the preceding claims, further comprising a second additive different from the impact modifier additive.

7. Composition according to claim 6, wherein the weight content of second additive varies from 1% to 25% by weight, preferably from 2% to 20% by weight, preferably from 3% to 16% by weight, more preferably from 4% to 12% by weight, advantageously from 5% to 10% by weight relative to the total weight of the composition.

8. Composition according to any one of the preceding claims, wherein the weight content of recycled polymer varies from 70% to 95% by weight, preferably from 80% to 92% by weight, advantageously from 85% to 90% by weight relative to the total weight of the composition.

9. Composition according to any one of the preceding claims, wherein the recycled polymer is selected from recycled polystyrenes, recycled acrylonitrile-butadiene-styrene polymers, and any of their mixtures.

10. Composition according to any one of the preceding claims, having a rate of increase in impact resistance greater than or equal to 1.1, preferably greater than or equal to 1.2, preferably greater than or equal to 1.5, more preferably greater than or equal to 1.8, advantageously greater than or equal to 2, the rate of increase in impact resistance being the ratio between the IZOD impact resistance value of the composition according to any one of the preceding claims and the IZOD impact resistance value of a composition differing from the composition of any one of the preceding claims only in that it is devoid of the impact modifying additive.

11. A method for preparing a composition according to any one of claims 1 to 10, comprising a step of mixing a polymer recycled and an impact modifying additive.

12. Use of an impact modifying additive in a composition comprising a recycled polymer to increase the impact resistance of said composition.

13. Consumer product comprising a composition according to any one of claims 1 to 10.

14. A method for manufacturing a consumer product, comprising a step selected from extrusion, injection, molding, rotomolding, thermoforming and calendering of a composition according to any one of claims 1 to 10.

15. Use of a composition according to any one of claims 1 to 10, for the manufacture of a consumer product.