Toy building brick made of recycled ABS (Acrylonitrile Butadiene Styrene) material

Abstract

The present invention relates to a toy assembly element made of recycled acrylonitrile-butadiene-styrene (ABS) material and manufactured by processing a resin comprising recycled ABS polymer.

Description

[0001] This application is a divisional application of the application with the filing date of April 15, 2021, international application number PCT / EP2021 / 059742, national application number 202180042139.0, and invention title "Toy building bricks made of recycled ABS material". Technical Field

[0002] The present invention relates to toy building elements made of recycled (recycled) acrylonitrile-butadiene-styrene (ABS) material and manufactured by processing a resin comprising recycled ABS polymer. Background Art

[0003] Toy building elements have been manufactured and sold for many years. Traditionally, such toy building elements are made of petroleum-based polymers such as ABS.

[0004] ABS is an engineering thermoplastic polymer manufactured by polymerizing styrene and acrylonitrile in the presence of polybutadiene. The proportions can be 15 - 35% acrylonitrile, 5 - 30% butadiene, and 40 - 60% styrene. ABS consists of an amorphous continuous phase and a rubbery (rubber) dispersed phase. The poly(styrene-co-acrylonitrile) (SAN) copolymer forms the continuous phase, and the second phase consists of dispersed butadiene or butadiene copolymer. The butadiene particles have a SAN layer grafted onto their surface, which makes the two phases compatible. The properties of ABS result from the composition, the thermoplastic and rubbery phase characteristics, and their interaction. Thus, the SAN content and molecular weight control properties such as processability, heat resistance, surface hardness, and chemical resistance. The butadiene content mainly contributes to toughness.

[0005] ABS can be manufactured by emulsion polymerization and bulk polymerization. Depending on whether the ABS is produced by emulsion or bulk polymerization, ABS materials with different properties are obtained. For example, when ABS is produced by emulsion polymerization, a high-gloss surface of the ABS material can be obtained, while when the ABS material is produced by bulk polymerization, a low surface gloss is usually obtained.

[0006] The increasing concern about the reduction of petroleum resources and the impact of global warming have prompted the development of recycled ABS and technologies for producing ABS polymers by using biomass as a renewable resource.

[0007] ABS can be produced by using biomass as a renewable resource. WO 2015 / 034948A1 describes methods for producing bio-based organic chemicals such as bioacrylic acid, bioacrylonitrile, and bio-1,4-butadiene using renewable carbon sources as raw materials. In the first stage, bio-1,3-propanediol is obtained from a renewable carbon source by microbial fermentation, and in the second stage, the bio-1,3-propanediol is converted into bioacrylic acid or bioacrylonitrile or bio-1,4-butanediol.

[0008] ABS can also be produced by using materials that have been obtained with carbon capture technology, i.e., materials that have been produced using carbon monoxide and / or carbon dioxide that have been directly captured from air or gases from industrial processes. Such carbon capture technologies include, for example, absorption, adsorption, chemical looping, and membrane separation technologies. The captured carbon oxides can then be converted into hydrocarbons, such as alcohols or ethanol, which can be used as sources for the preparation of new monomers or polymers.

[0009] ABS can also be obtained by mechanical or chemical recycling of ABS materials.

[0010] The mechanical recycling of ABS only involves mechanical processes such as grinding, washing, separating, drying, regranulating, and compounding. In a typical recycling process, waste ABS plastics are collected and washed to remove contaminants. The clean plastics are then ground into flakes, which can be compounded and granulated or reprocessed into pellets.

[0011] One problem associated with using mechanically recycled ABS materials is that the properties of the recycled ABS materials are generally poorer than those of virgin ABS materials. This is due to degradation phenomena that occur during the life of the ABS and during melt reprocessing operations that accelerate degradation. During reprocessing, the ABS material is subjected to high temperatures and shear stresses, which result in different types of degradation reactions. The degree of degradation depends on the number of cycles and the processing temperature. It is also expected that for post-consumer recycled ABS, exposure to light, elevated temperatures, and chemicals during use will cause further degradation. It is believed that ABS degrades due to chain scission and crosslinking, producing oligomeric products that can migrate to the surface and brittle crosslinked polybutadiene particles. The chemical changes have a significant negative impact on, for example, impact strength, and it is necessary to improve the properties of the recycled polymer by adding suitable additives or by blending it with virgin polymers.

[0012] Another problem associated with the use of mechanically recycled ABS material is the presence of hazardous and / or unacceptable additives and other unwanted substances in the waste ABS used for recycling. The ABS waste is usually washed before recycling, but this washing step does not remove all of the additives and other unwanted substances present in the waste. Some types of additives can be hazardous and thus their presence in the recycled ABS material is unacceptable when used to manufacture toys such as toy building elements. In particular, substances classified as carcinogenic, mutagenic or toxic for reproduction (CMR) category 1A, 1B or 2 according to Regulation (EC) No 1272 / 2008 are unwanted substances in the recycled material. In addition, the presence of toxic metals must be avoided. Flame retardants in waste from WEEE (waste electrical and electronic equipment) are another example of unacceptable types of additives. Other types of additives that can be present in waste ABS include pigments such as iron oxide, which contribute to the continuous degradation of the ABS material during its lifetime before the ABS article is discarded as waste. Other types of additives can be impact modifiers that affect the impact strength of the recycled ABS material, lubricants that can affect the processing and frictional properties of the material, and colorants that can affect both the color and mechanical properties of the recycled ABS material. The ABS waste can also contain unwanted substances that have been absorbed during the use phase. Such substances can include organic solvents, cleaning agents and food ingredients. The ABS waste can also contain decorations, which include other monomers and solvents.

[0013] Another problem associated with the use of mechanically recycled ABS polymer is that recycled ABS is only commercially available in dark grey and black. Suitable coloring treatments must be developed to produce brightly colored toys made from recycled ABS material.

[0014] Chemical recycling of ABS refers to any method by which ABS waste is converted by chemical means into its virgin monomers and / or oligomers, which can be used to produce new virgin polymers to form ABS articles. This type of chemical recycling method includes pyrolysis and chemical depolymerization. Chemical recycling also refers to any method in which a suitable solvent can be used to dissolve the ABS waste and then the dissolved ABS polymer is usually recovered either by precipitation of the polymer or by evaporation of the solvent. This type of chemical recycling process is commonly referred to as "solvent dissolution".

[0015] Pyrolysis refers to the decomposition of the ABS material at elevated temperatures in the absence of oxygen. Pyrolysis converts the plastic into pyrolysis oil that can be further refined. The resulting oil can then be used to prepare new virgin polymers by known polymerization methods.

[0016] Chemical depolymerization is a process of decomposing polymers into monomers, oligomers, or a mixture of monomers and / or oligomers and / or their intermediates using chemicals. This process removes additives and colorants from the monomers / intermediates. New virgin polymers can be produced by polymerization of the monomers. Currently, there is no commercially available technology suitable for the depolymerization of ABS waste. However, new virgin ABS polymers can be manufactured by polymerization of monomers that have been recovered by the depolymerization of other types of plastic waste. For example, styrene monomers can be recovered by the depolymerization of polystyrene as described in WO 2016 / 049782.

[0017] Solvent dissolution involves selectively extracting polymers using solvents. Any additives and colorants are removed and the resulting polymer is typically recovered by precipitation of the polymer or by evaporation of the solvent. The polymer chains and structure are not decomposed. Solvent-based ABS recycling technologies have also been developed, in which many solvents have been proposed for dissolving ABS, such as acetone and tetrahydrofuran (THF).

[0018] One problem associated with using ABS polymers recovered from the solvent dissolution recycling process is that solvent extraction also removes all additives. This means that the recycled ABS material will not have the desired properties, such as viscosity, mold release, friction, fillers, and flame retardants, and may require new protective additives, such as heat stabilizers, antioxidants, UV stabilizers, etc.

[0019] Another problem associated with using ABS polymers recovered from the solvent dissolution recycling process is that solvent extraction will result in a mixture containing different SAN chains and butadiene spheres. Compensating for the unforeseen mixture of material components is a challenge. Therefore, it may be necessary to add short-chain or long-chain SAN to change the rheology or stiffness, and it may be necessary to add butadiene spheres to improve the impact properties. It may also be necessary to add different types of additives to compensate for the additives lost during the solvent dissolution process.

[0020] The main problem associated with the use of recycled ABS, regardless of how it is manufactured, is the polymer composition that is non-uniform compared to the virgin polymer composition. The degree of variation mainly depends on the waste: the more uniform the waste, the smaller the degree of variation. It must be expected that recycled ABS will have significant variations in the ratio between styrene, butadiene, and acrylonitrile, the chain length of the SAN copolymer, the size and size distribution of the butadiene spheres, and the degree of SAN grafting on the surface of the butadiene spheres. Therefore, more effort is needed to manufacture recycled ABS that is suitable for and conducive to manufacturing articles such as toy building elements, in order to obtain articles with satisfactory properties such as satisfactory impact strength, surface friction, and color. In particular, if it is intended to manufacture articles with surface gloss, it is important to know in advance that the ABS waste has been produced by emulsion polymerization and that it also contains butadiene spheres of suitable size, since the size of the butadiene spheres in the ABS material has been shown to be important for obtaining a smooth surface of the finished product. Summary of the Invention

[0021] The present invention relates to toy building elements made from recycled ABS (acrylonitrile-butadiene-styrene) material and manufactured by processing a resin comprising a recycled ABS polymer. The inventors of the present invention surprisingly found that toy building elements can be manufactured by processing a resin comprising a recycled ABS polymer.

[0022] In a first aspect, the present invention relates to toy building elements made from recycled ABS material.

[0023] In a second aspect, the present invention relates to a method for manufacturing toy building elements made from recycled ABS material. Description of the Drawings

[0024] Figure 1 Shows a conventional box-shaped 2*4 brick.

[0025] Figure 2 Shows a method for manufacturing toy building elements by processing a resin that comprises a mechanically recycled ABS polymer and / or a chemically recycled ABS polymer recovered from a dissolution recycling process.

[0026] Figure 3 Shows a method for manufacturing toy building elements by processing a resin comprising a mechanically recycled ABS polymer.

[0027] Figure 4 Shows a method for manufacturing toy building elements by processing a resin comprising a mechanically recycled ABS polymer, wherein the waste ABS material is a waste toy building element.

[0028] Figure 5A method of manufacturing a toy building element by processing a resin comprising a chemically recycled ABS polymer recovered from a dissolution recovery process is shown. In this embodiment, both the SAN phase and the butadiene spheres are recovered.

[0029] Figure 6 A method of manufacturing a toy building element by processing a resin comprising a chemically recycled ABS polymer recovered from a dissolution recovery process is shown. In this embodiment, only the SAN phase is recovered and mixed with additives and virgin butadiene and optionally other ABS polymers.

[0030] Figure 7 A method of manufacturing a toy building element by processing a resin comprising a chemically recycled ABS polymer recovered from a dissolution recovery process is shown. In this embodiment, only the SAN phase is recovered and mixed with additives and virgin ABS having a high butadiene content. Detailed Description

[0031] The present invention relates to toy building elements made from recycled ABS material.

[0032] As used herein, the term "toy building element" includes traditional toy building elements in the form of box-shaped building bricks, which are provided with knobs on the upper side and complementary tubes on the lower side. Traditional box-shaped building bricks are shown in Figure 1 . Traditional box-shaped toy building bricks were first disclosed in US 3,005,282 and are sold under the trade names and widely. The term also includes other similar box-shaped building bricks, which are produced by other companies different from the LEGO Group and are therefore sold under other trademarks different from the trademark LEGO.

[0033] The term "toy building element" also includes other types of toy building elements that form part of a toy building set, which typically includes a plurality of building elements that are compatible and can therefore be interconnected with each other. Such toy building sets are also sold under the trademark LEGO, such as bricks, Technic and Some of these toy building components include toy building figures, such as miniature figures (see, for example, US 05 / 877,800), which have complementary tubes on the lower side so that the figures can be connected to other toy building elements in the toy building set. The term "toy building element" also includes such toy building figures. The term also includes similar toy building elements, which are produced by other companies different from the LEGO Group and are therefore sold under other trademarks different from the trademark LEGO.

[0034] Toy building elements can have a variety of shapes, sizes, and colors. Bricks and One difference between bricks is The size of the bricks is Twice the size of the bricks in all dimensions. A traditional box-shaped Toy building bricks are approximately 3.2 cm long, 1.6 cm wide, and 0.96 cm high (excluding the knobs), and each knob has a diameter of approximately 0.48 cm. In contrast, bricks with 4*2 knobs on the upper side are approximately 6.4 cm long, 3.2 cm wide, and 1.92 cm high (excluding the knobs), and each knob has a diameter of approximately 0.96 cm.

[0035] The toy building element is made of recycled ABS material, and the element is made by processing a resin that includes mechanically recycled ABS polymer and / or chemically recycled ABS polymer collected from a solvent dissolution recycling process.

[0036] As used herein, the term "recycled ABS material" refers to an ABS material obtained by processing a resin that includes recycled ABS polymer. The recycled ABS polymer is obtained from ABS waste. The ABS waste can be mechanically recycled ABS material or chemically recycled ABS material. The recycled ABS polymer in the resin is mechanically recycled ABS polymer and / or chemically recycled ABS polymer collected from a solvent dissolution recycling process. In addition, the resin can also include virgin ABS polymer and / or chemically recycled ABS polymer collected from a pyrolysis recycling method and / or recycled ABS polymer collected from a chemical depolymerization recycling method.

[0037] "Mechanically recycled ABS material" refers to an ABS material recycled from mechanically recycled ABS material. Mechanical recycling only involves mechanical processes such as grinding, washing, separating, drying, pelletizing, and compounding. In a typical recycling process, ABS waste is collected and washed to remove contaminants. Then the clean plastic is ground into flakes, which can be mixed and pelletized or reprocessed into pellets.

[0038] "Chemically recycled ABS material" includes ABS materials made from ABS waste that has undergone pyrolysis, chemical depolymerization, solvent dissolution, or any other suitable chemical recycling method.

[0039] "Pyrolysis" refers to the decomposition of an ABS material into pyrolysis oil at an elevated temperature in the absence of oxygen. Then new virgin polymers can be prepared from the resulting oil by known polymerization methods.

[0040] "Chemical depolymerization" refers to the process of decomposing a polymer into monomers, monomer mixtures, or intermediates thereof using chemical reagents. New virgin polymers can be produced by polymerization of the monomers.

[0041] "Solvent dissolution" refers to the selective extraction of a polymer using a solvent. The extracted polymer is recovered by precipitation of the polymer or by evaporation of the solvent. The polymer chains and structure are not decomposed. Butadiene exists as separate spheres in ABS. Solvent dissolution does not change the chemical bonds in the polymer chains, but there is a risk of physical changes in the shape and size of the butadiene spheres. Therefore, it may be necessary to discard the butadiene spheres during solvent dissolution.

[0042] The term "recovered ABS polymer" refers to an ABS polymer included in mechanically recycled ABS waste or a polymer chemically recovered from ABS waste during solvent dissolution. The term also relates to virgin ABS polymers produced in a pyrolysis recovery process or a chemical depolymerization recovery process. When the term relates to virgin ABS polymers, it also includes polymers in which only one or two monomers have been recovered by pyrolysis or chemical depolymerization. For example, the term includes an ABS polymer in which some or all of the styrene monomers have been recovered by chemical depolymerization of polystyrene, while the acrylonitrile and butadiene monomers may be non-recovered monomers produced by conventional manufacturing methods.

[0043] In some embodiments, the recovered ABS material includes a recovered ABS polymer obtained from mechanically recycled ABS waste. In other embodiments, the recovered ABS material includes a recovered ABS polymer obtained from chemically recycled ABS waste, where the ABS polymer has been recovered using a solvent dissolution recovery method. In other embodiments, the recovered ABS material includes a mixture of recovered ABS polymers obtained from mechanically recycled ABS waste and chemically recycled ABS waste, where the ABS polymer has been recovered using a solvent dissolution recovery method. In further embodiments, the recovered ABS material may also include virgin ABS polymer and / or virgin ABS polymer, i.e., a recovered ABS polymer obtained from a pyrolysis recovery method and / or from a chemical depolymerization recovery method.

[0044] Toy building elements are manufactured by injection molding (injection moulding) or by additive manufacturing techniques or by a combination of injection molding and additive manufacturing techniques. Alternatively, these toy building elements are manufactured by extrusion, optionally followed by molding using thermoforming or similar techniques.

[0045] The injection molding of toy building elements is a traditional way of manufacturing toy building bricks. This manufacturing technique has been used for many years and is well known to those skilled in the art. In some embodiments, the toy building elements are manufactured by injection molding a resin comprising recycled ABS polymer. In other embodiments, the toy building elements are manufactured by two-component injection molding, where one component is a resin comprising recycled ABS polymer. In other embodiments, the toy building elements are manufactured by multi-component injection molding, where at least one component is a resin comprising recycled ABS polymer.

[0046] In recent years, new additive manufacturing techniques have been developed for building objects in, for example, polymeric materials. As used herein, the term "additive manufacturing" or "additive manufactured" refers to building the bricks in an additive manner, i.e., by adding new material on top of a substrate or on top of newly added material, by repeatedly solidifying thin layers of liquid or droplets on a substrate or on a previously cured liquid layer or droplet, or by repeatedly printing a thermoplastic polymer material on a substrate or on a previously printed plastic material, or by additive welding of plastic material, for example by using a laser.

[0047] In some embodiments, the toy building elements are manufactured by injection molding. In other embodiments, the toy building elements are manufactured by additive manufacturing. In other embodiments, the toy building elements are manufactured by a combination of injection molding and additive manufacturing. For example, such a combined manufacturing technique is described in WO2014 / 005591, where toy building elements with a high degree of design individuality are manufactured by adding material layer by layer on the surface of a conventionally injection-molded box-shaped building brick.

[0048] In other embodiments, the toy building elements are manufactured by extrusion. Optionally, the extrusion process is followed by molding using thermoforming or a similar technique.

[0049] It is known that the size of the butadiene spheres in ABS material affects the glossiness of the surface of an article made of the ABS material. In the toy industry, a glossy surface is most often targeted. Therefore, in a preferred embodiment, the size of the butadiene spheres in the recycled ABS material is less than or equal to 0.5 microns.

[0050] One of the main problems with using recycled ABS material to manufacture new toy building elements is the loss of mechanical properties, especially impact strength. Sometimes, this problem can be solved at least in part by adding virgin ABS polymer to the resin before processing the resin into toy building elements. Alternatively, the problem can be solved by adding virgin ABS polymer or a mixture of virgin ABS polymer and virgin ecological ABS polymer.

[0051] In one embodiment, the resin further comprises virgin ABS polymer. In some embodiments, the amount of virgin ABS polymer is at least 5 wt% of the total polymer in the resin, such as at least 10 wt%, at least 30 wt%, at least 50 wt%, at least 70 wt% or at least 90 wt%. In other embodiments, the amount of virgin ABS polymer is 5-95 wt% of the total polymer in the resin, such as 10-95 wt%, 30-95 wt%, 50-95 wt%, 70-95 wt% or 80-95 wt%. In other embodiments, the amount of virgin ABS polymer is 5-50 wt% of the total polymer in the resin, such as 5-30 wt%, 5-20 wt% or 5-10 wt%.

[0052] In other embodiments, the resin comprises native ABS polymer. As used herein, the term "native ABS polymer" refers to chemically recycled ABS polymer recovered from a pyrolysis recovery process and / or from a chemical depolymerization recovery process. In some embodiments, the amount of native ABS polymer is at least 5 wt% of the total polymer in the resin, such as at least 10 wt%, at least 30 wt%, at least 50 wt%, at least 70 wt% or at least 90 wt%. In other embodiments, the amount of native ABS polymer is 5-95 wt% of the total polymer in the resin, such as 10-95 wt%, 30-95 wt%, 50-95 wt%, 70-95 wt% or 80-95 wt%. In other embodiments, the amount of native ABS polymer is 5-50 wt% of the total polymer in the resin, such as 5-30 wt%, 5-20 wt% or 5-10 wt%.

[0053] In other embodiments, the resin comprises a mixture of virgin ABS polymer and native ABS polymer. In some embodiments, the total amount of virgin ABS polymer and native ABS polymer is at least 5 wt% of the total polymer in the resin, such as at least 10 wt%, at least 30 wt%, at least 50 wt%, at least 70 wt% or at least 90 wt%. In other embodiments, the total amount of virgin ABS polymer and native ABS polymer is 5-95 wt% of the total polymer in the resin, such as 10-95 wt%, 30-95 wt%, 50-95 wt%, 70-95 wt% or 80-95 wt%. In other embodiments, the total amount of virgin ABS polymer and native ABS polymer is 5-50 wt% of the total polymer in the resin, such as 5-30 wt%, 5-20 wt% or 5-10 wt%.

[0054] In a preferred embodiment, the recycled ABS waste is a discarded toy building element, and thus the recycled material is very similar to the virgin material, except that the recycled material has been processed into a toy building element which has then been ground into pellets or flakes. In such cases, it has surprisingly been found that toy building elements made entirely from mechanically recycled toy building elements having satisfactory mechanical properties (i.e., impact strength) can be manufactured even without introducing new additives (such as impact modifiers) for improving mechanical properties.

[0055] In some embodiments, the resin does not contain any virgin ABS polymer. In other embodiments, the amount of virgin ABS polymer is 0 - 95 wt%, such as 0 - 50 wt%, 0 - 25 wt%, 0 - 10 wt% or 0 - 5 wt% of the total polymer in the resin.

[0056] The weight ratio between the mechanically recycled ABS polymer and the virgin ABS polymer can range from 100:0 to 1:99, such as 100:0 to 10:90, 90:10 to 50:50 or 50:50 to 90:10.

[0057] In certain embodiments, the recycled ABS waste is subjected to a solvent dissolution recycling process. In this process, the ABS polymer from the waste is dissolved in a solvent, and then the dissolved ABS polymer is usually recovered by precipitation of the polymer or by evaporation of the solvent. In the dissolved state, the polymer can separate into two phases; one phase contains poly(styrene - co - acrylonitrile) chains, also known as the SAN phase, and the other phase contains a butadiene copolymer, also known as butadiene spheres.

[0058] In some embodiments, it may be suitable to recover both the SAN phase and the butadiene spheres, while in other embodiments, it may be suitable to recover only the SAN phase. In some cases where only the SAN phase is suitably recovered, the recycled SAN copolymer can be mixed with butadiene, which can be virgin butadiene or recycled butadiene or a mixture thereof. In other cases where only the SAN phase is suitably recovered, the recycled SAN copolymer can be mixed with an ABS having a high butadiene content. The ABS having a high butadiene content can be virgin ABS or recycled ABS or a mixture thereof.

[0059] As used herein, the term "ABS having a high butadiene content" refers to an ABS having at least 20 wt% butadiene.

[0060] In other embodiments, the resin comprises a mechanically recycled ABS polymer and a chemically recycled ABS polymer recovered from a solvent dissolution recycling process. In some embodiments, the resin further comprises a virgin ABS polymer.

[0061] Alternatively, the resin comprises a mechanically recycled ABS polymer, a recycled SAN copolymer, and additional ABS having a high butadiene content. The ABS having a high butadiene content can be virgin ABS or recycled ABS or a mixture thereof.

[0062] In other embodiments, the resin comprises a mechanically recycled ABS polymer and a SAN phase recovered from ABS waste that has undergone a solvent dissolution recovery process. In this embodiment, it may be suitable to further add butadiene or ABS having a high butadiene content or a mixture thereof. The butadiene and the ABS having a high butadiene content can be of virgin or recycled origin or a mixture thereof.

[0063] In an actual injection molding system, the amount of recycled ABS is determined by the volume ratio of the mold and the mold runner system. When new production starts, virgin material is fed into the mold during the first run. The material remaining in the runner system and thus not forming part of the final injection molded element is ground back into the form of pellets or flakes or the like and used as recycled material, which is mixed with the virgin material and fed back into the mold again. Such recycling continues until a steady state is reached, where the amount of recycled material will represent a certain constant percentage of the input material, and where the rest of the material will be virgin material. This constant percentage of recycled material will be referred to as "recycled material after % steady state".

[0064] The inventors of the present invention have surprisingly found that for molded elements produced in a mold operating at a low % recycled material after steady state, a significant increase in the Charpy V-notch is observed. A specific example is described in Example 2, where a mold (Mold 1) operating at 42% recycled material after steady state produces molded rods having a relative Charpy V-notch value of 108%. Another mold (Mold 2) operating at 90% recycled material after steady state shows no reduction in the relative Charpy V-notch value. These findings are very unexpected because when ABS material is recycled, a reduction in the relative Charpy V-notch value would be expected.

[0065] Accordingly, in a particularly preferred embodiment of the present invention, toy building elements are produced by injection molding using a mold operating at 20 - 95 wt%, such as 30 - 90 wt% recycled material after steady state.

[0066] The resin processed into toy building elements may comprise a bio-based ABS polymer and / or a hybrid bio-based ABS polymer.

[0067] As used herein, the term "bio-based ABS polymer" refers to an ABS polymer produced by the chemical or biochemical polymerization of monomers derived from biomass. In some embodiments, the bio-based polymer is produced by the chemical polymerization of monomers, all of which are derived from biomass. In other embodiments, the bio-based polymer is produced by the biochemical polymerization of monomers, all of which are derived from biomass.

[0068] As used herein, the term "hybrid bio-based ABS polymer" refers to an ABS polymer produced by polymerization, wherein at least one ABS monomer is derived from biomass and at least one ABS monomer is derived from petroleum, petroleum by-products, or petroleum-derived feedstocks. The ABS monomers can be virgin monomers, chemically recycled monomers, or a mixture of virgin and recycled monomers. The polymerization process is typically a chemical polymerization process.

[0069] In some embodiments, at least a portion of the recycled ABS polymer is a bio-based ABS polymer and / or a hybrid bio-based ABS polymer. In other embodiments, at least a portion of the virgin ABS polymer is a bio-based ABS polymer and / or a hybrid bio-based ABS polymer. In other embodiments, at least a portion of the recycled ABS polymer and at least a portion of the virgin ABS polymer are bio-based ABS polymers and / or hybrid bio-based ABS polymers.

[0070] In other embodiments, the toy building element can include an ABS polymer produced using carbon capture technology. As used herein, the term "ABS polymer produced using carbon capture technology" refers to a polymer that contains carbon atoms from carbon monoxide and / or carbon dioxide that are directly captured from the air or from gases from industrial processes.

[0071] In one embodiment, the total amount of ABS polymer in the resin is at least 50 wt% relative to the total weight of the resin. In other embodiments, the total amount of ABS polymer is at least 60 wt% or at least 70 wt% or at least 80 wt% relative to the total weight of the resin. In other embodiments, the total amount of ABS polymer is at least 85 wt%, such as at least 90 wt%, relative to the total weight of the resin.

[0072] In another embodiment, the total amount of ABS polymer in the resin is 50 - 99 wt% relative to the total weight of the resin. In other embodiments, the total amount of ABS polymer is 60 - 95 wt% or 70 - 90 wt% or 80 - 85 wt% relative to the total weight of the resin. In other embodiments, the total amount of ABS polymer is 85 - 97 wt% or 90 - 97 wt% or 90 - 95 wt% or 90 - 92 wt% relative to the total weight of the resin.

[0073] As used herein, the term "total amount of ABS polymer in the resin" refers to the total amount of ABS polymer in the resin, regardless of whether the ABS polymer is recycled ABS polymer, virgin ABS polymer, bio-based ABS polymer, hybrid bio-based ABS polymer, and / or ABS polymer produced using carbon capture technology.

[0074] It may be beneficial to add additives to a resin comprising recycled ABS polymer to improve the performance of toy building elements manufactured by processing the resin. In some embodiments, the resin comprising recycled ABS polymer comprises one or more additives such as impact modifiers, fillers, antioxidants, lubricants, flame retardants, colorants, light stabilizers / UV absorbers, and plasticizers.

[0075] The impact modifier can be a reactive impact modifier or it can be a non-reactive impact modifier. In some embodiments, the resin of recycled ABS polymer can comprise reactive and non-reactive impact modifiers. In a preferred embodiment, the resin comprises a reactive impact modifier.

[0076] As used herein, the term "impact modifier" refers to a reagent that increases the impact strength of injection molded ABS elements when added to the resin.

[0077] The reactive impact modifier has functionalized end groups. The functionalization serves two purposes: 1) to bind the impact modifier to the polymer matrix, and 2) to modify the interfacial energy between the polymer matrix and the impact modifier to enhance dispersion. Preferred examples of such functionalized end groups include glycidyl methacrylate, maleic anhydride, and carboxylic acids.

[0078] In the present invention, a reactive impact modifier is preferred. In a preferred embodiment, the impact modifier is a copolymer of the formula X / Y / Z, where X is an aliphatic or aromatic hydrocarbon polymer having 2-8 carbon atoms, Y is a moiety comprising acrylate or methacrylate having 3-6 and 4-8 carbon atoms respectively, and Z is a moiety comprising methacrylic acid, glycidyl methacrylate, maleic anhydride, or carboxylic acid.

[0079] In a preferred embodiment, the impact modifier can be described by the following formula:

[0080]

[0081] where

[0082] n is an integer from 1 to 4,

[0083] m is an integer from 0 to 5,

[0084] k is an integer from 0 to 5, and

[0085] R is an alkyl group of 1 to 5 carbons or 1 hydrogen atom.

[0086] X accounts for 40 - 90% (wt / wt) of the impact modifier, and Y accounts for 0 - 50% (wt / wt) of the impact modifier, such as 10 - 40% (wt / wt), preferably 15 - 35% (wt / wt), most preferably 20 - 35% (wt / wt), and Z accounts for 0.5 - 20% (wt / wt) of the impact modifier, preferably 2 - 10% (wt / wt), most preferably 3 - 8% (wt / wt).

[0087] In other embodiments, X accounts for 70 - 99.5% (wt / wt) of the impact modifier, preferably 80 - 95% (wt / wt), most preferably 92 - 97% (wt / wt), and Y accounts for 0% (wt / wt) of the impact modifier, and Z accounts for 0.5 - 30% (wt / wt) of the impact modifier, preferably 5 - 20% (wt / wt), most preferably 3 - 8% (wt / wt).

[0088] Suitable examples of specific impact modifiers that can be used in the resins of the present invention include ethylene - ethyl acrylate - glycidyl methacrylate and ethylene - butyl acrylate - glycidyl methacrylate. Commercially available impact modifiers include Paralid TM EXM - 2314 (an acrylic copolymer from Dow Chemical Company), AX8700, AX8900, Lotader AX8950 and AX8840 (manufactured by Arkema) and PTW (manufactured by DuPont).

[0089] Other suitable examples of specific impact modifiers that can be used in the resins of the present invention include acid anhydride - modified ethylene acrylates. Commercially available impact modifiers include 3210, 3410, 4210, 3430, 4402, 4503, 4613, 4700, 5500, 6200, 8200, HX8210, HX8290, LX4110, TX8030 (manufactured by Arkema), 21E533, 21E781, 21E810 and 21E830 (manufactured by DuPont).

[0090] In other embodiments, the impact modifier is a modified ethylene vinyl acetate, such as 1123 or 1124 (manufactured by DuPont); an acid-modified ethylene acrylate, such as 2002 or 2022 (manufactured by DuPont); a modified ethylene acrylate, such as 22E757, 22E780 or 22E804 (manufactured by DuPont), an acid anhydride-modified ethylene-vinyl acetate, such as 30E670, 30E671, 30E753 or 30E783 (manufactured by DuPont); and an acid / acrylate-modified ethylene-vinyl acetate, such as 3101 or 3126 (manufactured by DuPont), an acid anhydride-modified ethylene-vinyl acetate, such as E418, 3810, 3859, 3860 or 3861 (manufactured by DuPont), an acid anhydride-modified ethylene-vinyl acetate, such as 3930 or 39E660 (manufactured by DuPont); and an acid anhydride-modified high density polyethylene, such as 4033 or 40E529 (manufactured by DuPont); an acid anhydride-modified linear low density polyethylene, such as 4104, 4105, 4109, 4125, 4140, 4157, 4164, 41E556, 41E687, 41E710, 41E754, 41E755, 41E762, 41E766, 41E850, 41E865 or 41E871 (manufactured by DuPont); acid anhydride modified low density polyethylene, such as 4206, 4208, 4288 or 42E703 (manufactured by DuPont); or acid anhydride modified polypropylene, such as 50E571, 50E662, 50E725, 50E739, 50E803 or 50E806 (manufactured by DuPont).

[0091] Other suitable impact modifiers include maleic anhydride grafted impact modifiers. Specific examples of such impact modifiers include chemically modified ethylene acrylate copolymers, such as A560 (manufactured by DuPont), acid anhydride modified polyethylene, such as E158 (manufactured by DuPont), acid anhydride modified polyethylene resin, such as E564 or E589 or E226 or E528 (manufactured by DuPont), acid anhydride modified high density polyethylene, such as E100 or E265 (manufactured by DuPont), acid anhydride modified ethylene copolymer, such as N525 (manufactured by DuPont), or chemically modified propylene copolymer, such as E353 (manufactured by DuPont).

[0092] Other suitable impact modifiers include ethylene - acid copolymer resins, such as copolymers based on ethylene - methacrylic acid (EMAA) and copolymers based on ethylene - acrylic acid (EAA). Specific examples of copolymer impact modifiers based on ethylene - methacrylic acid include 403, 407HS, 411HS, 0609HSA, 0903, 0903HC, 908HS, 910, 910HS, 1202HC, 599, 699, 925 and 960 (manufactured by DuPont). Specific examples of ethylene-acrylic acid based copolymers are 30707, 30907, 31001, 3990 and AE (manufactured by DuPont). Other specific examples of ethylene copolymers based on ethylene-acrylic acid (EAA) include EscorTM 5000, EscorTM 5020, EscorTM 5050, EscorTM 5080, EscorTM 5100, EscorTM 5200 and EscorTM 6000 (manufactured by ExonMobile Chemical).

[0093] Other suitable impact modifiers include ionomers of ethylene acid copolymers. Specific examples of such impact modifiers include 1601, 1601-2, 1601-2LM, 1605, 8150, 8320, 8528 8660 (manufactured by DuPont).

[0094] In other embodiments, the impact modifier is an alkyl methacrylate-silicone / alkyl acrylate graft copolymer. The "alkyl methacrylate" of the graft copolymer may be selected from methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, and butyl methacrylate. The "silicone / alkyl acrylate" in the graft copolymer refers to a polymer obtained by polymerizing a mixture of a silicone monomer and an alkyl acrylate monomer. The silicone monomer may be selected from dimethylsiloxane, hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, trimethyltriphenylcyclotetrasiloxane, tetramethyltetraphenylcyclotetrasiloxane, and octaphenylcyclotetrasiloxane. The alkyl monomer may be selected from methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, butyl methacrylate, and butyl methacrylate. The graft copolymer is in the form of a core-shell rubber and has a grafting rate of 5 to 90% (wt / wt), the glass transition temperature of the core is -150 to -20 °C, and the glass transition temperature of the shell is 20 to 200 °C. In one embodiment of the present invention, the graft copolymer is a methyl methacrylate-silicone / butyl acrylate graft copolymer. Specific examples include S-2001, S-2100, S-2200, and S-2501 manufactured by Mitsubishi Rayon Co., Ltd., Japan.

[0095] Other suitable impact modifiers include the silicone polymers mentioned in US 4,616,064, which contain silicone units and at least one of carbonate, urethane, or amide units.

[0096] Suitable impact modifiers also include those mentioned in paragraphs

[0043] -

[0072] of WO 2018 / 089573.

[0097] Other suitable impact modifiers include core-shell impact modifiers, such as those mentioned in US 5,409,967.

[0098] The resin including recycled ABS polymer may also include a filler. Suitable examples of the filler include inorganic particulate materials, nanocomposites, or mixtures thereof.

[0099] Suitable examples of the inorganic particulate materials include inorganic oxides such as glass, MgO, SiO2, TiO2 and Sb2O3; hydroxides such as Al(OH)3 and Mg(OH)2; salts such as CaCO3, BaSO4, CaSO4 and phosphates; silicates such as talc, mica, kaolin, wollastonite, montmorillonite, nanoclay, feldspar and asbestos; metals such as boron and steel; carbon-graphite such as carbon fiber, graphite fiber and flakes, carbon nanotubes and carbon black. Suitable examples of the inorganic particulate materials also include surface-treated and / or surface-modified SiO2 and TiO2 such as alumina surface-modified TiO2.

[0100] Suitable examples of the nanocomposites include clay-filled polymers such as clay / low density polyethylene (LDPE) nanocomposites, clay / high density polyethylene (HDPE) nanocomposites, acrylonitrile-butadiene-styrene (ABS) / clay nanocomposites, polyimide (PI) / clay nanocomposites, epoxide / clay nanocomposites, polypropylene (PP) / clay nanocomposites, poly(methyl methacrylate) (PMMA) / clay nanocomposites and polyvinyl chloride (PVC) / clay nanocomposites; alumina-filled polymers such as epoxide / alumina nanocomposites, PMMA / alumina nanocomposites, PI / alumina nanocomposites, PP / alumina nanocomposites, LDPE / alumina nanocomposites and crosslinked polyethylene (XLPE) / alumina nanocomposites; barium titanate-filled polymers such as HDPE / barium titanate nanocomposites and polyetherimide (PEI) / barium titanate nanocomposites; silica-filled polymers such as PP / silica nanocomposites, epoxide / silica nanocomposites, PVC / silica nanocomposites, PEI / silica nanocomposites, PI / silica nanocomposites, ABS / silica nanocomposites and PMMA / silica nanocomposites; and zinc oxide-filled polymers such as LDPE / zinc oxide nanocomposites, PP / zinc oxide nanocomposites, epoxide / zinc oxide nanocomposites and PMMA / zinc oxide nanocomposites.

[0101] The resin including recycled ABS polymer may also include antioxidants. Suitable examples of the antioxidants include phosphites, phenols, amines and any mixture thereof.

[0102] Resins comprising recycled ABS polymers may also include lubricants. The addition of lubricants may be very important in order to obtain toy building elements with satisfactory surface properties, such as satisfactory surface friction. Suitable examples of lubricants include fatty acids, fatty acid amides and bisamides, fatty acid esters, stearic acid, metal stearates, inorganic stearates, lignite wax, paraffin wax, polyethylene wax, polypropylene wax, silicone-based lubricants and any mixtures thereof.

[0103] Resins comprising recycled ABS polymers may also include flame retardants. Suitable examples of flame retardants include mineral flame retardants, such as magnesium hydroxide or aluminum hydroxide; organic flame retardants, such as carboxylic acids and organophosphorus flame retardants.

[0104] Resins comprising recycled ABS polymers may also include colorants. Suitable examples of colorants include organic pigments, inorganic pigments, solvent dyes, zinc ferrite, carbon black, titanium dioxide and aluminum oxide.

[0105] Resins comprising recycled ABS polymers may also include light stabilizers and / or UV absorbers. Suitable examples of light stabilizers / UV absorbers include benzoates, benzophenones, benzotriazoles, hindered amines and triazines.

[0106] Resins comprising recycled ABS polymers may also include plasticizers. Suitable examples of plasticizers include hydrocarbon processing oils, phosphate esters, such as or for example triphenyl phosphate and resorcinol bis(diphenyl phosphate), or oligophosphate esters, long-chain fatty acids and aromatic sulfonamides.

[0107] The type and variety of ABS waste are important for the uniformity of the ABS polymer in the resin. The more uniform the waste, the more uniform the resin. Advantageously, resins of recycled ABS polymers with uniform length, crosslinking and butadiene sphere size are used. In one embodiment, the recycled ABS polymer is produced from ABS waste from the toy industry.

[0108] In a preferred embodiment, the ABS waste is discarded toy building elements. The main advantage of using discarded toy building elements from the manufacturer's own production plant is that their chemical composition is known and also how to process the material. If the waste is color-sorted before recycling, it is easier to produce recycled toy building elements with a uniform color. If the waste is not color-sorted before recycling, then it may be necessary to first remove the colorant and then add a new colorant in order to obtain a final toy building element with a satisfactory color.

[0109] Some ABS waste contains harmful additives, and thus their presence in recycled ABS materials is unacceptable when used to manufacture toys such as toy building elements. Examples of such harmful additives include harmful flame retardants such as halogenated flame retardants; plasticizers such as phthalates and bisphenol A; harmful lubricants such as fluoropolymers; and inorganic materials such as cadmium and manganese. Other types of additives that may be present in waste ABS include pigments such as iron oxide, which contribute to the continuous degradation of the ABS material during the lifetime of the article before the ABS article is discarded as waste.

[0110] Generally, the recycled ABS material must meet the requirements specified, for example, in Regulation (EC) No 1907 / 2006 and the Toy Safety Directive (2009 / 48 / EC), otherwise the ABS waste is not suitable for use in manufacturing toy building elements.

[0111] In particular, the amount of carcinogenic, mutagenic or reprotoxic (CMR) substances classified as category 1A, 1B or 2 under Regulation (EC) No 1272 / 2008 must be below specific limits. Thus, the total content of carcinogenic substances in categories 1A and 1B must be 1000 ppm or less, while the total content of carcinogenic substances in category 2 must be 10000 ppm or less. The total content of mutagenic substances in categories 1A and 1B must be 1000 ppm or less, while the total content of mutagenic substances in category 2 must be 10000 ppm or less. The total content of reprotoxic substances in categories 1A and 1B must be 3000 ppm or less, while the total content of reprotoxic substances in category 2 must be 30000 ppm or less.

[0112] Equally important is that the metal content in the ABS waste is below the migration limits specified, for example, in the Toy Safety Directive (2009 / 48 / EC), otherwise the waste is not suitable for use in manufacturing toy building elements. In particular, the following migration limits must not be exceeded: aluminium: 70000 mg / kg; antimony: 560 mg / kg; arsenic: 47 mg / kg; barium: 18750 mg / kg; boron: 15000 mg / kg; cadmium 17 mg / kg; chromium(III): 460 mg / kg; chromium(IV): 0.053 mg / kg; cobalt: 130 mg / kg; copper: 7700 mg / kg; lead: 160 mg / kg; manganese: 15000 mg / kg; mercury: 94 mg / kg; nickel: 930 mg / kg; selenium: 460 mg / kg; strontium: 56000 mg / kg; tin: 180000 mg / kg; organotin: 12 mg / kg; and zinc: 46000 mg / kg.

[0113] To obtain harmless ABS waste with uniform physical and chemical properties, screening the waste before recycling may be beneficial or even necessary. Such screening may include analytical methods for quantifying the ratio of the butadiene copolymer to SAN, detecting and / or quantifying carcinogenic substances, mutagenic substances, substances toxic to reproduction, antioxidants, heavy metals, halogenated substances, lubricants, flame retardants, colorants, etc. Suitable analytical methods may include attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) to determine the ratio of the butadiene copolymer to SAN. Thermogravimetric analysis (TGA) and / or differential scanning calorimetry - oxidation induction time (DSC-OIT) for determining the thermal oxidative stability of the waste material. X-ray fluorescence spectroscopy (XRF) for determining the amounts of heavy metals and / or halogenated substances, etc. It may also be necessary to screen the ABS waste for the size of the butadiene spheres and study how the spheres are distributed within the SAN phase. Direct methods for determining the distribution of butadiene spheres in the SAN phase include scanning electron microscopy (SEM) and transmission electron microscopy (TEM), while indirect methods include measuring the gloss of the reinjected molded parts.

[0114] The present invention also relates to a method for manufacturing toy building elements. The method is as Figure 2 shown.

[0115] a) Providing and screening ABS waste,

[0116] b) Recovering a recycled ABS polymer from the screened ABS waste by subjecting the ABS waste of step a to a grinding and / or solvent dissolution recycling process,

[0117] c) Obtaining a resin by mixing the recovered ABS polymer of step b with one or more additives and optionally one or more ABS polymers selected from: virgin ABS polymer, chemically recycled ABS polymer recovered from pyrolysis, and chemically recycled ABS polymer recovered from chemical depolymerization, and

[0118] d) Manufacturing toy building elements by processing the resin of step c

[0119] Suitable resins obtained in step c and processed in step d include those described above.

[0120] The recycled ABS polymer in the resin is derived from ABS waste that has undergone one or more screening processes before being introduced into the resin, such that only materials containing harmless and / or acceptable additives are introduced into the resin.

[0121] In step a, the ABS waste is screened to obtain at least one property selected from the following:

[0122] The quantity of substances classified as carcinogenic, mutagenic or toxic for reproduction (CMR) in categories 1A, 1B or 2 according to Regulation (EC) No 1272 / 2008

[0123] The migration limits of one or more metals selected from aluminium, antimony, arsenic, barium, boron, cadmium, chromium III, chromium IV, cobalt, copper, lead, manganese, mercury, selenium, strontium, tin, organotin and zinc

[0124] The quantity of oxides

[0125] The quantity of phthalates

[0126] The quantity of flame retardants

[0127] The ratio of the butadiene copolymer to SAN

[0128] The size and size distribution of the butadiene spheres, and

[0129] The crosslinking level of the butadiene spheres

[0130] It is very important that the quantity of substances classified as carcinogenic, mutagenic or toxic for reproduction (CMR) in categories 1A, 1B or 2 according to Regulation (EC) No 1272 / 2008 is below the specified limits, otherwise the waste is not suitable for use in the manufacture of toys. Thus, the total content of carcinogenic substances in categories 1A and 1B must be 1000 ppm or less, while the total content of carcinogenic substances in category 2 must be 10000 ppm or less. The total content of mutagenic substances in categories 1A and 1B must be 1000 ppm or less, while the total content of mutagenic substances in category 2 must be 10000 ppm or less. The total content of substances toxic for reproduction in categories 1A and 1B must be 3000 ppm or less, while the total content of substances toxic for reproduction in category 2 must be 30000 ppm or less.

[0131] It is also important that the metal content in the ABS waste is below the migration limits specified, for example, in the Toy Safety Directive (2009 / 48 / EC), otherwise the waste is not suitable for use in the manufacture of toy building elements. In particular, the following migration limits must not be exceeded: aluminium: 70000 mg / kg; antimony: 560 mg / kg; arsenic: 47 mg / kg; barium: 18750 mg / kg; boron: 15000 mg / kg; cadmium 17 mg / kg; chromium (III): 460 mg / kg; chromium (IV): 0.053 mg / kg; cobalt: 130 mg / kg; copper: 7700 mg / kg; lead: 160 mg / kg; manganese: 15000 mg / kg; mercury: 94 mg / kg; nickel: 930 mg / kg; selenium: 460 mg / kg; strontium: 56000 mg / kg; tin: 180000 mg / kg; organotin: 12 mg / kg; and zinc: 46000 mg / kg.

[0132] The amount of iron oxide must also be kept at a very low level to avoid chemical degradation of the ABS polymer over time, especially the formation of ABS monomers, which results in poor mechanical properties of the manufactured toy building elements and thus becomes a product safety issue. Additionally, if the ABS waste is intended for use in manufacturing toys, the amounts of toxic compounds such as phthalates and flame retardants must be avoided.

[0133] It is also important to screen the ratio of the butadiene copolymer to SAN and the size of the butadiene spheres in the waste ABS material. The butadiene content in the ABS material is preferably 15 - 22 wt% based on the total ABS polymer. The size of the butadiene spheres is preferably less than or equal to 0.5 microns to obtain a glossy surface of the manufactured toy building elements.

[0134] In some cases, the waste ABS material may be very non-uniform, and in such cases, it may be necessary to classify the waste ABS material before screening the above properties.

[0135] In step b, the screened ABS waste is subjected to a grinding and / or solvent dissolution recovery process to obtain the recovered ABS polymer.

[0136] Figure 3 and Figure 4 A method for manufacturing toy building elements by processing a resin including a mechanically recovered ABS polymer is shown in. In this method, the screened ABS waste is ground. In the grinding step, the recovered material is crushed / cut into small pieces of material. This step is important to obtain a uniform material mixture that is easily mixed with additives and optionally other ABS polymers and is also easily melted during the manufacturing process of the toy building elements, i.e., during injection molding, extrusion, or additive manufacturing.

[0137] Figure 5 、 6 A method for manufacturing toy building elements by processing a resin including a chemically recovered ABS polymer is shown in and 7. In this method, the screened ABS waste is subjected to a solvent dissolution recovery process. Generally, the waste ABS material is ground before dissolution to facilitate the dissolution of the waste material, but the grinding step is not mandatory. During the dissolution step, the ABS waste is dissolved, and the ABS polymer can be separated into two phases: one phase contains poly(styrene-co-acrylonitrile) chains, also known as the SAN phase, and the other phase contains the butadiene copolymer, also known as the butadiene spheres. In some embodiments, both the SAN phase and the butadiene spheres are recovered ( Figure 5 ), while in other embodiments, only the SAN phase is recovered ( Figure 6 and 7 ).

[0138] In step c, the recycled ABS polymer is mixed with other compounds to form a resin. Preferably, the mixing step is a compounding step. During mixing, one or more additives are mixed with the recycled ABS polymer, and optionally, virgin and / or virgin-like ABS polymers may also be incorporated into the resin. Suitable additives include impact modifiers, fillers, antioxidants, lubricants, flame retardants, colorants, light stabilizers / UV absorbers, and / or plasticizers. The virgin and / or virgin-like ABS polymers can be bio-based ABS polymers and / or hybrid bio-based polymers. Additionally, the virgin-like ABS polymer can be an ABS polymer recovered from a chemical pyrolysis recovery process or a chemical depolymerization recovery process.

[0139] In certain preferred embodiments, as Figure 4 shown, the waste ABS material is a discarded toy building element. In these embodiments, the addition of additives may not be necessary since the discarded toy building element may already have the mechanical properties required to manufacture toy building elements with the desired properties.

[0140] In step d, building brick elements are manufactured by processing the resin obtained in step c. In some embodiments, the toy building elements are manufactured by injection molding. In such embodiments, the mixing of the recycled ABS polymer with additives and / or colorants and optionally other virgin or virgin-like ABS polymers can be carried out before feeding the resin into an injection molding machine. In some embodiments, the mixing can be carried out as a dry blending step or a compounding step. In other embodiments, the mixing can be carried out by using a compounding step in an extruder before the injection molding step. In other embodiments, the additives can be mixed into a masterbatch and then the masterbatch is mixed with the remaining ABS resin during the feeding of the injection molding machine. Alternatively, the mixing can be carried out during the feeding of the resin into the injection molding machine.

[0141] In other embodiments, the toy building elements are manufactured by extrusion, optionally followed by molding using thermoforming or similar techniques.

[0142] In some embodiments, the toy building element is manufactured by additive manufacturing. Suitable examples of additive manufacturing techniques are those in which the toy building element is built by photopolymerization additive manufacturing or thermoplastic additive manufacturing, such as liquid-based additive manufacturing, toner-based additive manufacturing, powder-based additive manufacturing, or pellet-based additive manufacturing.

[0143] Preferably, the method further comprises the following steps, wherein before forming the resin obtained in step c into toy building elements in step d, quality control is performed on the resin, and this quality control is mainly to ensure that important mechanical properties are necessary in order to obtain final toy building elements with desired properties. Examples of mechanical properties that are typically measured include one or more of impact strength, surface friction, surface gloss, and color.

[0144] Example

[0145] In the following examples, it is described how to recycle ABS by regrinding molded elements and runners, and then using the regrind material to produce new elements by injection molding. In Example 1, all of the ABS material was recycled, and in Example 2, the recycled ABS was mixed with virgin ABS and then injection molded into new elements. The impact strength of the injection molded elements was tested by the "Charpy V-notch test".

[0146] Charpy V-notch test

[0147] According to ISO 179-1 / 1eA, a molded plastic bar with dimensions of 6.0 × 4.0 × 50.0 mm 3 , B × W × H and the relevant material to be tested was cut with a notch cutter (ZNO, Zwick, Germany) with a notch tip diameter of 0.5 mm. The notched specimens were placed under a V-notch reverse pendulum and tested in a pendulum impact testing machine (HOT, Zwick, Germany) according to the principle described in ISO 179-1:2010.

[0148] Properties of Example 1 - Complete Recycling of ABS from Mechanical Recycling

[0149] The virgin ABS GP35 (supplied by INEOS Styrolution) was dried at 80 °C for 4 hours. The ABS was processed into impact bars and runners via injection molding (Arburg, Allrounder 470E 1000-400, 30 mm screw, Germany). Ten impact bars were tested in the Charpy V-notch test, and the results were recorded in the following table as regrind cycle 0.

[0150] The remaining runners and impact bars were ground into pellets in a plastic grinder. The ground ABS pellets were processed into impact bars and runners again, 10 impact bars were used in the Charpy V-notch test, and the results were recorded as regrind cycle 1. In a similar manner, the remaining impact bars and runners were ground and reprocessed in up to 10 regrind cycles.

[0151] The injection molding parameters are as follows:

[0152] Melting temperature: 240 °C

[0153] Mold temperature: 30 °C

[0154] The results are shown in the following table.

[0155] Number of regrinding cycles Relative Charpy V-notch value 0 100 1 100 5 95 10 88

[0156] The results show that one regrind cycle does not seem to affect the Charpy V-notch at all, while 5 regrind cycles result in a relative Charpy V-notch value decrease from 100 to 95. In the case of producing toy building elements, such a reduction may still be acceptable. A further decrease in the relative Charpy V-notch to 88 was observed after 10 regrind cycles. This indicates that toy building elements made from ABS recycled 10 times are likely to have unacceptable mechanical properties due to insufficient impact strength. Therefore, in order to increase the impact strength to an acceptable level, new or additional impact modifiers need to be mixed into the recycled material.

[0157] Example 2 Properties of Mechanically Recycled ABS - Partial Recycling of ABS

[0158] Two molds for producing components of different sizes were used to test the effect of applying different amounts of mechanically recycled ABS during the injection molding process. In this study, the amount of mechanically recycled ABS was represented by the percentage of the mechanical regrind runner system that was fed back into the molding process of the ABS. The two molds used in this test were configured to run with 42% and 90% regrind of the runner during the molding process. These two molds were used to study whether supplementing the regrind ABS with different levels of virgin ABS could help maintain good overall impact properties of the molded components. The above two molds were used to produce the input materials for 3 additional molds that ran with 37%, 51% and 85% regrind respectively.

[0159] The virgin ABS GP35 (supplied by INEOS Styrolution) was dried at 80 °C for 4 hours. The ABS was processed into LEGO components using molds 1 and 2 via injection molding (Arburg, Allrounder 470E 1000 - 400, 30 mm screw, Germany). The regrind and virgin ABS were fed into the molds according to the following table. Due to the level of regrind material introduced in this process, the molds needed to produce many shots before the entire process stabilized, i.e., before reaching a steady-state condition. The number of shots to ensure a stable process is shown in the following table.

[0160]

[0161] Once a stable process is reached, samples of the blended material ready for molding are collected and these samples are processed into impact bars via injection molding. The molded impact bars are used for Charpy V-notch analysis and the results are shown in the table below.

[0162] In addition, the stable processing materials produced by Dies 1 and 2 are used as input materials for processing in Dies 3, 4, and 5. Once a stable process is reached, material samples are collected and used to produce the impact bars tested in the Charpy V-notch analysis. The results are shown in the table below.

[0163]

[0164]

[0165] The results show that adding a certain amount of mechanically recycled ABS to virgin ABS during the injection molding process surprisingly provides an increase in the relative Charpy V-notch value. In particular, Die 1 run with 42% regrind shows a relative Charpy V-notch value increase to 108%. Moreover, when the steady-state material from Die 1 is used as the input material for Die 3, the relative Charpy V-notch value further increases to 112% compared to using virgin material. The inventors of the present invention have observed such relative Charpy V-notch value increases several times, and it can indicate an improved dispersion of polybutadiene spheres when the recycled ABS material is mixed with virgin ABS.

[0166] The results also show that as the number of recycling cycles of the ABS increases, the relative Charpy V-notch value decreases, resulting in a decrease in the impact strength of the injection-molded components. The acceptable precise Charpy V-notch value for producing toy building components using recycled ABS will depend on the type of components produced; for example, traditional bricks require a higher impact strength than bricks. But ultimately, regardless of the type of component, the recycled ABS material can no longer produce toy building bricks with satisfactory mechanical properties, and new or additional impact modifiers or virgin ABS need to be mixed with the recycled ABS to produce toy building components with acceptable impact strength.

[0167] The above experimental results show that ABS can be mechanically recycled to a certain extent, but ultimately the mechanical properties need to be improved in order to produce toy building components with acceptable mechanical performance such as acceptable impact strength.

Claims

1. A toy building element, which is made of recycled ABS (acrylonitrile-butadiene-styrene) material and manufactured by processing a resin containing mechanically recycled ABS polymer, wherein the mechanically recycled ABS material or the resin containing mechanically recycled ABS material meets the requirements specified in Regulation (EC) No 1907 / 2006 and the Toy Safety Directive (2009 / 48 / EC), and it has: - The total content of carcinogenic substances of Class 1A and 1B is 1000 ppm or less, - The total content of carcinogenic substances of Class 2 is 10000 ppm or less, - The total content of mutagenic substances of Class 1A and 1B is 1000 ppm or less, - The total content of mutagenic substances of Class 2 is 10000 ppm or less, - The total content of reproductive toxicants of Class 1A and 1B is 3000 ppm or less, - The total content of reproductive toxicants of Class 2 is 30000 ppm or less, - The aluminum content is 70000 mg / kg or less, - The antimony content is 560 mg / kg or less, - The arsenic content is 47 mg / kg or less, - The barium content is 18750 mg / kg or less, - The boron content is 15000 mg / kg or less, - The cadmium content is 17 mg / kg or less, - The chromium(III) content is 460 mg / kg or less, - The chromium(IV) content is 0.053 mg / kg or less, - The cobalt content is 130 mg / kg or less, - The copper content is 7700 mg / kg or less, - The lead content is 160 mg / kg or less, - The manganese content is 15000 mg / kg or less, - The mercury content is 94 mg / kg or less, - The nickel content is 930 mg / kg or less, - The selenium content is 460 mg / kg or less, - The strontium content is 56000 mg / kg or less, - The tin content is 180000 mg / kg or less, - The organotin content is 12 mg / kg or less, and - The zinc content is 46000 mg / kg or less.

2. The toy building element according to claim 1, wherein the resin contains recycled ABS having uniform length, crosslinking, and uniform butadiene sphere size.

3. The toy building element according to claim 1 or 2, wherein the toy building element is manufactured by injection molding, extrusion, or additive manufacturing technology or by a combination of injection molding and additive manufacturing technology.

4. The toy building element according to claim 1 or 2, wherein the size of the butadiene spheres in the recycled ABS polymer is less than or equal to 0.5 microns.

5. The toy building element according to claim 1 or 2, wherein the resin further contains virgin ABS polymer, and the weight ratio between the mechanically recycled ABS polymer and the virgin ABS polymer is in the range of 100:0 to 5:

95.

6. The toy building element according to claim 1 or 2, wherein at least a part of the ABS polymer is a bio-based ABS polymer and / or a hybrid bio-based ABS polymer and / or an ABS polymer produced using carbon capture technology.

7. The toy building element according to claim 1 or 2, wherein the total amount of the ABS polymer in the resin is at least 50% by weight relative to the total weight of the resin.

8. The toy building element according to claim 1 or 2, wherein the resin further comprises one or more additives selected from impact modifiers, fillers, antioxidants, lubricants, flame retardants, colorants, light stabilizers / UV absorbers, and plasticizers.

9. The toy building element according to claim 1 or 2, wherein the recycled ABS polymer is produced from ABS waste materials originating from the toy industry.

10. The toy building element according to claim 9, wherein the ABS waste materials are discarded toy building elements.

11. The toy building element according to claim 1 or 2, wherein the element is produced by injection molding using a mold operating with 20 - 95% by weight, such as 30 - 90% by weight, of recycled materials after reaching a steady state.

12. A method for manufacturing a toy building element, which comprises the following steps: a) providing and screening ABS waste materials such that only the ABS polymer as defined in claim 1 is introduced into the resin, b) recovering the recycled ABS polymer from the screened ABS waste materials by subjecting the ABS waste materials of step a to grinding, c) obtaining a resin by mixing the recovered ABS polymer of step b with one or more additives and optionally virgin ABS polymer, and d) manufacturing a toy building element by processing the resin of step c.

13. The method according to claim 12, wherein the ABS waste materials are screened for at least one property selected from: - the amount of carcinogenic, mutagenic or reprotoxic (CMR) substances classified as category 1A, 1B or 2 according to Regulation (EC) No 1272 / 2008, - the migration limits of one or more metals selected from aluminum, antimony, arsenic, barium, boron, cadmium, chromium (III), chromium (IV), cobalt, copper, lead, manganese, mercury, selenium, strontium, tin, organotin, and zinc, - the amount of oxides, - the amount of phthalates, - the amount of flame retardants, - the ratio of butadiene copolymer to SAN, - the size and size distribution of butadiene spheres, and - the crosslinking level of butadiene spheres.

14. The method according to claim 12 or 13, wherein the recovered ABS polymer is compounded with one or more additives selected from impact modifiers, fillers, antioxidants, lubricants, flame retardants, colorants, light stabilizers / UV absorbers, and plasticizers.

15. The method according to claim 12 or 13, wherein the toy building element is manufactured by injection molding, extrusion, or additive manufacturing of the resin obtained in step c, or by a combination of injection molding and additive manufacturing of the resin obtained in step c.

16. The method according to claim 12 or 13, wherein quality control is performed on the resin obtained in step c before forming the resin into a toy building element in step d.

17. The method according to claim 16, wherein the quality control includes measuring one or more mechanical properties of the resin, wherein the mechanical properties are selected from - Impact strength, - Surface friction, - Surface gloss, and - Color.

18. The method according to claim 12 or 13, wherein the ABS waste is a discarded toy building element, and wherein mixing the collected ABS polymer with one or more additives in step c is optional.

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