Toy building blocks made from recycled ABS material

Abstract

The present invention relates to toy building elements made from recycled ABS (acrylonitrile butadiene styrene) material and manufactured by processing a resin that includes recycled ABS polymer.

Description

[Technical Field]

[0001] The present invention relates to toy building elements made from recycled ABS (acrylonitrile butadiene styrene) material and manufactured by processing a resin that includes recycled ABS polymer. [Background technology]

[0002] Toy building blocks have been manufactured and marketed for many years.

[0003] Traditionally, such toy building elements have been made from petroleum-based polymers such as ABS.

[0004] ABS is an engineering thermoplastic polymer produced by polymerizing styrene and acrylonitrile in the presence of polybutadiene. The ratios may vary from 15 to 35% acrylonitrile, 5 to 30% butadiene, and 40 to 60% styrene. ABS consists of an amorphous-continuous phase and a rubbery dispersed phase. Poly(styrene-co-acrylonitrile) (SAN) copolymer forms the continuous phase and a second phase consisting of dispersed butadiene or butadiene copolymer. Butadiene particles have a layer of SAN grafted onto their surface, which makes the two phases compatible. The properties of ABS are obtained by the composition, the characteristics of the thermoplastic and rubbery phases, and the interactions between them. Therefore, the SAN content and molecular weight control properties such as processability, heat resistance, surface hardness, and chemical resistance. The butadiene content primarily contributes to toughness.

[0005] ABS can be produced by emulsion polymerization and bulk polymerization. ABS materials with different properties can be obtained depending on whether the ABS is produced by emulsion or bulk polymerization. For example, a highly glossy surface of an ABS material can be obtained when the ABS is produced by emulsion polymerization, while a weak surface gloss is usually obtained when the ABS material is produced by bulk polymerization.

[0006] Increasing concerns about dwindling petroleum resources and the effects of global warming have encouraged the development of technologies for recycling ABS and 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 / 034948 A1 describes a method for producing bio-based organic chemicals, such as bioacrylic acid, bioacrylonitrile, and bio-1,4-butadiene, using a renewable carbon source as a raw material. In a first step, bio-1,3-propanediol is derived from a renewable carbon source via microbial fermentation, and in a second step, the bio-1,3-propanediol is converted to bioacrylic acid, bioacrylonitrile, or bio-1,4-butadiol.

[0008] ABS can also be produced using materials obtained using carbon capture techniques, i.e., materials produced using carbon monoxide and / or carbon dioxide captured directly from the air or from gases produced by industrial processes. Such carbon capture techniques include, for example, absorption, adsorption, chemical looping, and membrane separation. The captured carbon oxides can then be converted into hydrocarbons, such as methanol or ethanol, which can be used as a feedstock for making new monomers or polymers.

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

[0010] Mechanical recycling of ABS involves only mechanical processes, such as crushing, washing, separating, drying, re-granulating, and compounding. In a typical recycling process, waste ABS plastic is collected and cleaned to remove foreign matter. The cleaned plastic is then crushed into flakes, which can be compounded and pelletized, or reprocessed into granules.

[0011] One problem associated with the use of mechanically recycled ABS materials is that their properties are typically inferior to those of virgin ABS materials. This is due to degradation phenomena that occur throughout the ABS's service life and during melt reprocessing, which accelerates the degradation process. During reprocessing, ABS materials are subjected to high temperatures and shear stress, which induce different types of degradation reactions. The extent of degradation depends on the number of cycles and the processing temperature. In post-consumer recycled ABS, exposure to light, elevated temperatures, and chemicals during use is also expected to induce further degradation. ABS is believed to degrade due to chain scission and crosslinking, producing oligomeric products that can migrate to the surface and brittle crosslinked polybutadiene particles. Chemical changes have a significant adverse effect on, for example, impact strength, making it necessary to improve the performance of recycled polymers by adding suitable additives or blending them with virgin polymers.

[0012] Another issue with the use of mechanically recycled ABS materials is the presence of harmful and / or unacceptable additives and other undesirable substances in the waste ABS used for recycling. ABS waste is typically washed before recycling, but this washing step does not remove all additives and other undesirable substances present in the waste material. Some types of additives can be harmful and therefore their presence is unacceptable in recycled ABS materials when used to manufacture toys, such as toy building blocks. In particular, substances classified as carcinogenic, mutagenic, or toxic to reproduction (CMR) in categories 1A, 1B, or 2 under Regulation (EC) No. 1272 / 2008 are undesirable in recycled materials. The presence of toxic metals must also be avoided. Flame retardants in waste from WEEE (Waste Electrical and Electronic Equipment) are a further example of an unacceptable type of additive. Other types of additives that may be present in waste ABS include pigments, such as iron oxides, which contribute to the continued degradation of ABS materials during the life of the ABS item before it is discarded as waste. Other types of additives include impact modifiers, which affect the impact strength of recycled ABS materials; lubricants, which can affect material processability and friction; and colorants, which can affect both the color and mechanical properties of recycled ABS materials. ABS waste may also contain unwanted substances absorbed during the use phase. Such substances may include organic solvents, detergents, and food ingredients. ABS waste may also contain decorations containing other monomers and solvents.

[0013] Yet another problem with the use of mechanically recycled ABS polymer is that recycled ABS is only commercially available in dark gray and black. To produce toys made from recycled ABS material that are brightly colored, suitable coloring processes must be developed.

[0014] Chemical recycling of ABS refers to any process in which ABS waste is chemically converted back into the original monomers and / or oligomers, which can then be used to create new, virgin-like polymers to create ABS items. This type of chemical recycling process includes pyrolysis and chemical depolymerization. Chemical recycling also refers to any process in which ABS waste can be dissolved using a suitable solvent, and the dissolved ABS polymer is then recovered, typically by precipitating the polymer or evaporating the solvent. This type of chemical recycling process is typically referred to as "solvent dissolution."

[0015] Pyrolysis refers to the breakdown of ABS material at elevated temperatures in the absence of oxygen. Pyrolysis reduces the plastic to pyrolysis oil, which can be further refined. New, virgin-like polymer can then be made from the resulting oil through known polymerization processes.

[0016] Chemical depolymerization is a process that uses chemicals to break down polymers into monomers, oligomers, or mixtures of monomers and / or oligomers, and / or their intermediates. The process removes additives and colorants from the monomers / intermediates. New virgin-like polymers can be produced by polymerizing the monomers. Today, there are no commercially available technologies suitable for depolymerizing ABS waste. However, new virgin ABS polymers can be produced by polymerizing monomers recovered from the depolymerization of other types of plastic waste. For example, styrene monomer can be recovered from the depolymerization of polystyrene, as described in WO 2016 / 049782.

[0017] Solvent dissolution involves selective extraction of the polymer using a solvent. Any additives and colorants are removed, and the resulting polymer is typically recovered by precipitating the polymer or evaporating the solvent. The polymer chains and structure are not disrupted. Dissolution-based techniques for recycling ABS have also been developed, and many solvents, such as acetone and tetrahydrofuran (THF), have been suggested for dissolving ABS. [Prior art documents] [Patent documents]

[0018] [Patent Document 1] WO2015 / 034948 A1 [Patent Document 2] WO2016 / 049782 [Patent Document 3] US3,005,282 [Patent Document 4] US05 / 877,800 [Patent Document 5] WO2014 / 005591 [Patent Document 6] US4,616,064 [Patent Document 7] WO2018 / 089573 paragraphs

[0043] to

[0072] [Patent Document 8] US5,409,967 Summary of the Invention [Problem to be solved by the invention]

[0019] One problem with using ABS polymer recovered from solvent dissolution recycling processes is that solvent extraction also removes all additives, meaning the recycled ABS material will not have the required properties, such as viscosity, mold release, friction, fillers, and flame retardants, and may require new protective additives, such as heat stabilizers, antioxidants, and UV stabilizers.

[0020] Another problem with using ABS polymer recovered from the solvent dissolution recycling process is that the solvent extraction contains a mixture of different SAN chains and butadiene spheres. Compensating for this unpredictable mixture of material components presents a challenge. Therefore, adding short- or long-chain SAN may be necessary to modify the rheology or degree of cure, or adding butadiene spheres to improve impact properties. Adding different types of additives may also be necessary to compensate for additive losses during the solvent dissolution process.

[0021] A major problem with using recycled ABS is the recovery of polymer compositions, which, regardless of how they are produced, are less uniform compared to virgin polymer compositions. The degree of variability is primarily determined by the waste material: the more uniform the waste material, the lower the degree of variability. Recycled ABS should be expected to possess high variability 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 extent of SAN grafting to the surface of the butadiene spheres. Therefore, significant efforts are required to make recycled ABS suitable and useful for manufacturing items, such as toy building blocks, in order to obtain items with satisfactory properties, such as satisfactory impact strength, surface friction, and color. Specifically, if the goal is to manufacture items with a glossy surface, it is important to understand that the ABS waste material was previously produced by emulsion polymerization and to contain butadiene spheres of an appropriate size, since the size of the butadiene spheres in the ABS material is known to be important for obtaining a glossy surface on the finished item. [Means for solving the problem]

[0022] The present invention relates to toy building elements made from recycled ABS (acrylonitrile butadiene styrene) material and manufactured by processing a resin that includes recycled ABS polymer. The inventors have surprisingly found that toy building elements can be manufactured by processing a resin that includes recycled ABS polymer.

[0023] In a first aspect, the present invention relates to toy building elements made from recycled ABS material.

[0024] In a second aspect, the present invention relates to a method for manufacturing toy building elements made from recycled ABS material. [Brief explanation of the drawings]

[0025] [Figure 1] FIG. 1 shows the traditional boxed LEGO® with 2x4 blocks. [Figure 2] FIG. 1 illustrates a method for manufacturing toy building elements by processing resins comprising mechanically and / or chemically recycled ABS polymers recovered from a melt recycling process. [Figure 3] FIG. 1 illustrates a method for manufacturing toy building elements by processing a resin comprising mechanically recycled ABS polymer. [Figure 4] FIG. 1 illustrates a method for manufacturing toy building elements by processing resins containing mechanically recycled ABS polymer, where waste ABS material is a disposed toy building element. [Figure 5] 1 illustrates a method for manufacturing toy building elements by processing a resin containing chemically recycled ABS polymer recovered from a melt recycling process. In this embodiment, both the SAN phase and the butadiene spheres are recycled. [Figure 6] 1 illustrates a method for manufacturing toy building elements by processing a resin comprising chemically recycled ABS polymer recovered from a melt recycling process. In this embodiment, only the SAN phase is recycled and mixed with additives and virgin butadiene, and optionally further ABS polymer. [Figure 7]1 illustrates a method for manufacturing toy building elements by processing a resin containing chemically recycled ABS polymer recovered from a melt recycling process. In this embodiment, only the SAN phase is recycled and mixed with additives and virgin ABS with a high butadiene content. DETAILED DESCRIPTION OF THE INVENTION

[0026] The present invention is directed to toy building elements made from recycled ABS materials.

[0027] As used herein, the term "toy building element" includes a traditional toy building element in the form of a box-type building block with protrusions on the top surface and complementary tubes on the bottom surface. A traditional box-type toy building block is shown in FIG. 1. Traditional box-type toy building blocks were first disclosed in U.S. Pat. No. 3,005,282 and are widely sold under the trade names LEGO® and LEGO® DUPLO®. The term also includes other similar box-type building blocks produced by other companies that are not part of the LEGO Group and therefore sold under other trademarks than the trademark LEGO.

[0028] The term "toy building element" also includes other types of toy building elements that typically form part of a toy building set, including multiple building elements that fit together and thus can be connected to one another. Such toy building sets are also sold under the trademark LEGO, e.g., LEGO® bricks, LEGO® Technic, and LEGO® DUPLO®. Some of these toy building sets include toy building figures, e.g., LEGO® Minifigures (see, e.g., US 05 / 877,800), which have complementary tubular portions on their undersides so that the figures can be connected to other toy building elements in the toy building set. Such toy building figures are also encompassed by the term "toy building element." This term also includes similar toy building elements produced by other companies that are not part of the LEGO Group and therefore sold under other trademarks than the trademark LEGO.

[0029] Toy building elements are available in a wide variety of shapes, sizes, and colors. One difference between LEGO® bricks and LEGO® DUPLO® bricks is size, with a LEGO® DUPLO® brick being twice the size of a LEGO® brick in all dimensions. A traditional boxed LEGO® toy building block with 4x2 projections on its top surface measures approximately 3.2 cm long, 1.6 cm wide, and 0.96 cm high (excluding projections), with each projection having a diameter of approximately 0.48 cm. In contrast, a LEGO® DUPLO® brick with 4x2 projections on its top surface measures approximately 6.4 cm long, 3.2 cm wide, and 1.92 cm high (excluding projections), with each projection having a diameter of approximately 0.96 cm.

[0030] The toy building elements are made from recycled ABS material and the elements are Mechanically recycled ABS polymer and / or chemically recycled ABS polymer recovered from solvent dissolution recycling processes It is produced by processing a resin containing

[0031] As used herein, the term "recycled ABS material" refers to an ABS material obtained by processing a resin containing 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 can be: Mechanically recycled ABS polymer and / or chemically recycled ABS polymer recovered from solvent dissolution recycling processes Additionally, the resin may further comprise virgin ABS polymer, and / or chemically recycled ABS polymer recovered from a pyrolysis recycling process, and / or recycled ABS polymer recovered from a chemical depolymerization recycling process.

[0032] "Mechanically recycled ABS material" refers to ABS material recovered through mechanical recycling of ABS material. Mechanical recycling involves mechanical processes only, such as crushing, cleaning, separating, drying, regranulating, and compounding. In a typical recycling process, ABS waste material is collected and cleaned to remove foreign matter. The cleaned plastic is then crushed into flakes, which can be compounded and pelletized, or reprocessed into granules.

[0033] "Chemically recycled ABS material" includes ABS material made from ABS waste that has been subjected to pyrolysis, chemical depolymerization, solvent dissolution, or any other suitable chemical recycling process.

[0034] "Pyrolysis" refers to the breakdown of ABS material into pyrolysis oils at elevated temperatures in the absence of oxygen. New, virgin-like polymer can then be made from the resulting oils by known polymerization processes.

[0035] "Chemical depolymerization" refers to a process in which a polymer is broken down into monomers, a mixture of monomers, or an intermediate using a chemical agent. New, virgin-like polymer can be produced by polymerization of the monomers.

[0036] "Solvent dissolution" refers to the selective extraction of a polymer using a solvent. The extracted polymer is recovered by precipitating the polymer or evaporating the solvent. The polymer chains and structure are not disrupted. The butadiene exists in ABS as individual globules. 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 globules. Therefore, it may be necessary to dispose of the butadiene globules during the solvent dissolution process.

[0037] The term "recycled ABS polymer" refers to ABS polymer contained in mechanically recycled ABS waste or polymer chemically recovered from ABS waste in a solvent dissolution process. The term also refers to virgin-like ABS polymer produced in a pyrolysis recycling process or a chemical depolymerization recycling process. When referring to virgin-like ABS polymer, the term also includes polymers in which only one or two of the monomers have been recycled by pyrolysis or chemical depolymerization. For example, the term includes ABS polymers in which some or all of the styrene monomer has been recycled by chemical depolymerization of polystyrene, while the acrylonitrile and butadiene monomers may be non-recycled monomers produced by traditional manufacturing methods.

[0038] In some embodiments, the recycled ABS material comprises recycled ABS polymer obtained from mechanically recycled ABS scrap. In other embodiments, the recycled ABS material comprises recycled ABS polymer obtained from chemically recycled ABS scrap, where the ABS polymer was recovered using a solvent dissolution recycling process. In yet other embodiments, the recycled ABS material comprises a mixture of recycled ABS polymer obtained from mechanically recycled ABS scrap and chemically recycled ABS scrap, where the ABS polymer was recovered using a solvent dissolution recycling process. In further embodiments, the recycled ABS material may further comprise virgin ABS polymer and / or virgin-like ABS polymer, i.e., recycled ABS polymer recovered from a pyrolysis recycling process and / or a chemical depolymerization recycling process.

[0039] The toy building elements are manufactured by injection molding, or by additive manufacturing techniques, or by a combination of injection molding and additive manufacturing techniques. Alternatively, the toy building elements are manufactured by extrusion, optionally followed by shaping using thermoforming or similar techniques.

[0040] Injection molding of toy building elements is a traditional means of manufacturing toy building blocks. 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 of the components is a resin comprising recycled ABS polymer. In yet other embodiments, the toy building elements are manufactured by multi-component injection molding, where at least one of the components is a resin comprising recycled ABS polymer.

[0041] In recent years, new additive manufacturing techniques have been developed for assembling objects, for example, with polymeric materials. As used herein, the term "additive manufacturing" or "additively manufactured" means that blocks are assembled in an additive manner, i.e., by adding new material onto a substrate or onto newly added material, by repeatedly solidifying thin liquid layers or droplets onto a substrate or previously solidified liquid layers or droplets, or by repeatedly printing with a thermoplastic polymer material onto a substrate or previously printed plastic material, or by repeatedly brazing a plastic material in an additive manner, for example, by using a laser.

[0042] 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 still other embodiments, the toy building elements are manufactured by a combination of injection molding and additive manufacturing. Such combined manufacturing techniques are described, for example, in WO 2014 / 005591, where toy building elements with a high degree of design individuality are manufactured by adding material layer by layer to the surface of traditional injection molded box-shaped building blocks.

[0043] In yet other embodiments, the toy building elements are manufactured by extrusion. Optionally, the extrusion process is followed by shaping using thermoforming or similar techniques.

[0044] It is known that the size of the butadiene spheres in ABS materials affects the surface glossiness of items made from ABS materials. In the toy industry, glossy surfaces are very often a target. Therefore, in a preferred embodiment, the size of the butadiene spheres in the recycled ABS materials is 0.5 micrometers or less.

[0045] One of the main problems with producing new toy building elements using recycled ABS materials is the loss of mechanical properties, particularly impact strength. This problem can sometimes be at least partially solved by adding virgin ABS polymer to the resin before processing it into toy building elements. Alternatively, this problem can be solved by adding virgin-like ABS polymer or a mixture of virgin and virgin-like ABS polymers.

[0046] In one embodiment, the resin further comprises a virgin ABS polymer. In some embodiments, the amount of virgin ABS polymer is at least 5 wt% of the total amount of polymer in the resin, e.g., 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 ranges from 5 to 95 wt% of the total amount of polymer in the resin, e.g., 10-95 wt%, 30-95 wt%, 50-95 wt%, 70-95 wt%, or 80-95 wt%. In yet other embodiments, the amount of virgin ABS polymer ranges from 5 to 50 wt%, e.g., 5-30 wt%, 5-20 wt%, or 5-10 wt% of the total amount of polymer in the resin.

[0047] In other embodiments, the resin comprises a virgin-like ABS polymer. As used herein, the term "virgin-like ABS polymer" refers to a chemically recycled ABS polymer recovered from a pyrolysis recycling process and / or a chemical depolymerization recycling process. In some embodiments, the amount of virgin-like ABS polymer is at least 5 wt%, e.g., at least 10 wt%, at least 30 wt%, at least 50 wt%, at least 70 wt%, or at least 90 wt% of the total amount of polymer in the resin. In other embodiments, the amount of virgin-like ABS polymer ranges from 5 to 95 wt%, e.g., 10-95 wt%, 30-95 wt%, 50-95 wt%, 70-95 wt%, or 80-95 wt% of the total amount of polymer in the resin. In still other embodiments, the amount of virgin-like ABS polymer ranges from 5 to 50 wt%, e.g., 5-30 wt%, 5-20 wt%, or 5-10 wt% of the total amount of polymer in the resin.

[0048] In yet other embodiments, the resin comprises a mixture of virgin and virgin-like ABS polymers. In some embodiments, the combined amount of virgin and virgin-like ABS polymers is at least 5 wt%, e.g., at least 10 wt%, at least 30 wt%, at least 50 wt%, at least 70 wt%, or at least 90 wt% of the total amount of polymer in the resin. In other embodiments, the combined amount of virgin and virgin-like ABS polymers ranges from 5 to 95 wt%, e.g., 10-95 wt%, 30-95 wt%, 50-95 wt%, 70-95 wt%, or 80-95 wt% of the total amount of polymer in the resin. In still other embodiments, the combined amount of virgin and virgin-like ABS polymers ranges from 5 to 50 wt%, e.g., 5-30 wt%, 5-20 wt%, or 5-10 wt% of the total amount of polymer in the resin.

[0049] In a preferred embodiment, the recycled ABS waste material is discarded toy building elements, and therefore the recycled material is exactly like the virgin material, except that the recycled material has been processed into toy building elements and then crushed into pellets or flakes. In such cases, it has been surprisingly found that toy building elements made exclusively from mechanically recycled toy building elements have satisfactory mechanical properties, i.e., impact strength, and can be produced even without incorporating new additives to improve the mechanical properties, such as impact modifiers.

[0050] In some embodiments, the resin does not contain any virgin ABS polymer, while in other embodiments, the amount of virgin ABS polymer ranges from 0 to 95 wt%, e.g., 0-50 wt%, 0-25 wt%, 0-10 wt%, or 0-5 wt%, of the total amount of polymer in the resin.

[0051] The weight ratio between the mechanically recycled ABS polymer and the virgin ABS polymer may range from 100:0 to 1:99, such as from 100:0 to 10:90, from 90:10 to 50:50, or from 50:50 to 90:10.

[0052] In some embodiments, 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 the dissolved ABS polymer is then typically recovered by precipitating the polymer or evaporating 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 butadiene copolymers, also known as butadiene spheres.

[0053] In some embodiments, it may be preferable to recycle both the SAN phase and the butadiene spheres, while in other embodiments, it may be preferable to recycle only the SAN phase. In some cases where only the SAN phase is preferable to recycle, the recycled SAN copolymer may be blended with butadiene, which may be virgin or recycled butadiene, or a mixture thereof. In other cases where only the SAN phase is preferable to recycle, the recycled SAN copolymer may be blended with ABS having a high butadiene content. The ABS having a high butadiene content may be virgin or recycled ABS, or a mixture thereof.

[0054] As used herein, the term "ABS with a high content of butadiene" means ABS with at least 20 wt% butadiene.

[0055] In yet another embodiment, the resin is Mechanically recycled ABS polymer and chemically recycled ABS polymer recovered from solvent dissolution recycling process In some embodiments, the resin further comprises a virgin ABS polymer.

[0056] Alternatively, the resin comprises a mechanically recycled ABS polymer, a recycled SAN copolymer, and also a high butadiene content ABS, which can be virgin ABS or recycled ABS, or a mixture thereof.

[0057] In another embodiment, the resin comprises a mechanically recycled ABS polymer and a SAN phase recovered from ABS waste that has been subjected to a solvent dissolution recycling process. In this embodiment, it may be advantageous to further add butadiene or high-butadiene ABS, or a mixture thereof. The butadiene and high-butadiene ABS may be of virgin or recycled origin, or a mixture thereof.

[0058] In a practical injection molding system, the amount of recycled ABS is determined by the volumetric ratio of the mold and mold runner system. When a new production run is started, the mold is fed with virgin material on the first run. The material that remains in the runner system, and therefore does not form part of the final injection-molded element, is re-ground into pellets or flakes, etc., and used as recycled material to be mixed with the virgin material and fed back into the mold. This recycling continues until a steady-state situation is achieved, where the amount of recycled material represents a certain percentage of the input material, with the remainder of the material being virgin material. This certain percentage of recycled material is called "% recycled material after steady state."

[0059] The inventors have unexpectedly found that significant improvements in Charpy v-notch are observed for molded elements produced in molds flowing a low percentage of post-steady-state recycled material. A detailed example, described in Example 2, is a mold (Mold 1) flowing 42% post-steady-state recycled material, producing molded specimens with a relative Charpy v-notch value of 108%. Another mold (Mold 2) flowing 90% post-steady-state recycled material showed no decrease in relative Charpy v-notch value. These findings were highly unexpected, as a decrease in relative Charpy v-notch value was expected when ABS materials are recycled.

[0060] Thus, in a particular preferred embodiment of the present invention, the toy building elements are produced by injection molding using a mold that flows with 20-95 wt%, for example 30-90 wt%, of post-steady state recycled material.

[0061] The resin that is processed into the toy building elements may include bio-based ABS polymer and / or hybrid bio-based ABS polymer.

[0062] As used herein, the term "bio-based ABS polymer" refers to an ABS polymer produced by chemical or biochemical polymerization of monomers derived from biomass. In some embodiments, the bio-based polymer is produced by chemical polymerization of monomers derived entirely from biomass. In other embodiments, the bio-based polymer is produced by biochemical polymerization of monomers derived entirely from biomass.

[0063] As used herein, the term "hybrid bio-based ABS polymer" refers to an ABS polymer produced by polymerization in which at least one of the ABS monomers is derived from biomass and at least one of the ABS monomers is derived from petroleum, a petroleum by-product, or a petroleum-derived raw material. 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.

[0064] In some embodiments, at least a portion of the recycled ABS polymers are bio-based and / or hybrid bio-based ABS polymers. In other embodiments, at least a portion of the virgin ABS polymers are bio-based and / or hybrid bio-based ABS polymers. In still other embodiments, at least a portion of the recycled ABS polymers and at least a portion of the virgin ABS polymers are bio-based and / or hybrid bio-based ABS polymers.

[0065] In yet other embodiments, the toy building elements may include ABS polymer produced using carbon capture technology. As used herein, the term "ABS polymer produced using carbon capture technology" refers to a polymer containing carbon atoms from carbon monoxide and / or carbon dioxide captured directly from air or from gases from industrial processes.

[0066] In one embodiment, the total amount of ABS polymer in the resin is at least 50 wt% based on 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% based on the total weight of the resin. In other embodiments, the total amount of ABS polymer is at least 85 wt%, e.g., at least 90 wt%, based on the total weight of the resin.

[0067] In another embodiment, the total amount of ABS polymer in the resin is 50-99 wt% based on 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%, based on 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%, based on the total weight of the resin.

[0068] As used herein, the term "total amount of ABS polymer in the resin" means 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.

[0069] It can be beneficial to add additives to resins comprising recycled ABS polymers to improve the properties of the toy building elements produced by processing the resin. In some embodiments, resins comprising recycled ABS polymers include one or more additives, such as impact modifiers, fillers, antioxidants, lubricants, flame retardants, colorants, light stabilizers / UV absorbers, and plasticizers.

[0070] The impact modifier can be a reactive or non-reactive impact modifier. In some embodiments, the resin of recycled ABS polymer can contain both reactive and non-reactive impact modifiers. In a preferred embodiment, the resin contains a reactive impact modifier.

[0071] As used herein, the term "impact modifier" means an agent that, when added to a resin, increases the impact strength of injection molded ABS components.

[0072] The reactive impact modifier has a functionalized end group. The functionalization serves two purposes: 1) to bond the impact modifier to the polymer matrix, and 2) to modify the interfacial energy between the polymer matrix and the impact modifier to improve dispersion. Preferred examples of such functionalized end groups include glycidyl methacrylate, maleic anhydride, and carboxylic acids.

[0073] In the present invention, reactive impact modifiers are 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 to 8 carbon atoms, Y is an acrylate or methacrylate containing moiety having 3 to 6 and 4 to 8 carbon atoms, respectively, and Z is a methacrylic acid, glycidyl methacrylate, maleic anhydride, or carboxylic acid containing moiety.

[0074] In one preferred embodiment, the impact modifier has the formula: [C1] (In the formula, n is an integer from 1 to 4, m is an integer from 0 to 5; k is an integer from 0 to 5, R is an alkyl of 1 to 5 carbon or 1 hydrogen atom).

[0075] X constitutes 40 to 90% (wt / wt) of the impact modifier, Y constitutes 0 to 50% (wt / wt) of the impact modifier, for example 10 to 40% (wt / wt), preferably 15 to 35% (wt / wt), most preferably 20 to 35% (wt / wt), and Z constitutes 0.5 to 20% (wt / wt), preferably 2 to 10% (wt / wt), most preferably 3 to 8% (wt / wt) of the impact modifier.

[0076] In another embodiment, X constitutes 70-99.5% (wt / wt), preferably 80-95% (wt / wt), and most preferably 92-97% (wt / wt) of the impact modifier, Y constitutes 0% (wt / wt) of the impact modifier, and Z constitutes 0.5-30% (wt / wt), preferably 5-20% (wt / wt), and most preferably 3-8% (wt / wt) of the impact modifier.

[0077] Suitable examples of specific impact modifiers that can be used in the resins of the present invention include ethylene-ethylene acrylate-glycidyl methacrylate and ethylene-butyl acrylate-glycidyl methacrylate. Commercially available impact modifiers include Paraloid™ EXM-2314 (an acrylic copolymer from Dow Chemical Company), Lotader® AX8700, Lotader® AX8900, Lotader® AX8750®, Lotader® AX8950 and Lotader® AX8840 (manufactured by Arkema), and Elvaloy® PTW (manufactured by DuPont).

[0078] Other suitable examples of specific impact modifiers that may be used in the resins of the present invention include anhydride-modified ethylene acrylates. Commercially available impact modifiers include Lotader® 3210, Lotader® 3410, Lotader® 4210, Lotader® 3430, Lotader® 4402, Lotader® 4503, Lotader® 4613, Lotader® 4700, Lotader® 5500, Lotader® 6200, Lotader® 6300, Lotader® 6400, Lotader® 6500, Lotader® 6600, Lotader® 6700, Lotader® 6800, Lotader® 6900, Lotader® 7000, Lotader® 7100, Lotader® 7200, Lotader® 7300, Lotader® 7400, Lotader® 7500, Lotader® 7600, Lotader® 7700, Lotader® 7800, Lotader® 79 ... Lotader® 8200, Lotader® HX8210, Lotader® HX8290, Lotader® LX4110, Lotader® TX8030 (manufactured by Arkema), Bynel® 21E533, Bynel® 21E781, Bynel® 21E810 and Bynel® 21E830 (manufactured by DuPont).

[0079] In other embodiments, the impact modifier is a modified ethylene vinyl acetate such as Bynel® 1123 or Bynel® 1124 (manufactured by DuPont), acid modified ethylene acrylate such as Bynel® 2002 or Bynel® 2022 (manufactured by DuPont), modified ethylene acrylate such as Bynel® 22E757, Bynel® 22E780 or Bynel® 22E804 (manufactured by DuPont), or an unmodified ethylene vinyl acetate such as Bynel® 1123 or Bynel® 1124 (manufactured by DuPont). Hydride-modified ethylene vinyl acetates such as Bynel® 30E670, Bynel® 30E671, Bynel® 30E753, or Bynel® 30E783 (manufactured by DuPont) and acid / acrylate-modified ethylene vinyl acetates such as Bynel® 3101 or Bynel® 3126 (manufactured by DuPont), anhydride-modified ethylene vinyl acetates such as Bynel® E418, Bynel® 3810, Bynel® 3811, Bynel® 3812, Bynel® 3813, Bynel® 3814, Bynel® 3815, Bynel® 3816, Bynel® 3817, Bynel® 3818, Bynel® 3819 ... Bynel® 3859, Bynel® 3860 or Bynel® 3861 (manufactured by DuPont), anhydride-modified ethylene vinyl acetate such as Bynel® 3930 or Bynel® 39E660 (manufactured by DuPont), and anhydride-modified high density polyethylene such as Bynel® 4033 or Bynel® 40E529 (manufactured by DuPont), anhydride-modified linear low density polyethylene such as Bynel® 4104 , Bynel (registered trademark) 4105, Bynel (registered trademark) 4109, Bynel (registered trademark) 4125, Bynel (registered trademark) 4140, Bynel (registered trademark) 4157, Bynel (registered trademark) 4164, Bynel (registered trademark) 41E556, Bynel (registered trademark) 41E687, Bynel (registered trademark) 41E710, Bynel (registered trademark) 41E754, Bynel (registered trademark) 41E755, Bynel (registered trademark) 41E762, Bynel (registered trademark) 41E766, Bynel (registered trademark) 41E850,Bynel® 41E865 or Bynel® 41E871 (manufactured by DuPont), anhydride-modified low-density polyethylene such as Bynel® 4206, Bynel® 4208, Bynel® 4288 or Bynel® 42E703 (manufactured by DuPont), or anhydride-modified polypropylene such as Bynel® 50E571, Bynel® 50E662, Bynel® 50E725, Bynel® 50E739, Bynel® 50E803 or Bynel® 50E806 (manufactured by DuPont).

[0080] Other suitable impact modifiers include maleic anhydride grafted impact modifiers. Specific examples of such impact modifiers include chemically modified acrylic ethylene copolymers such as Fusabond® A560 (manufactured by DuPont), anhydride-modified polyethylene such as Fusabond® E158 (manufactured by DuPont), anhydride-modified polyethylene resins such as Fusabond® E564 or Fusabond® E589 or Fusabond® E226 or Fusabond® E528 (manufactured by DuPont), anhydride-modified high-density polyethylene such as Fusabond® E100 or Fusabond® E265 (manufactured by DuPont), anhydride-modified ethylene copolymers such as Fusabond® N525 (manufactured by DuPont), or chemically modified propylene copolymers such as Fusabond® E353 (manufactured by DuPont).

[0081] Still other suitable impact modifiers include ethylene-acid copolymer resins, such as ethylene-methacrylic acid (EMAA)-based copolymers and ethylene-acrylic acid (EAA)-based copolymers. Specific examples of ethylene-methacrylic acid-based copolymer impact modifiers include Nucrel® 403, Nucrel® 407HS, Nucrel® 411HS, Nucrel® 0609HSA, Nucrel® 0903, Nucrel® 0903HC, Nucrel® 908HS, Nucrel® 910, Nucrel® 910HS, Nucrel® 1202HC, Nucrel® 599, Nucrel® 699, Nucrel® 925, and Nucrel® 960 (manufactured by DuPont). Specific examples of ethylene-acrylic acid based copolymers include Nucrel® 30707, Nucrel® 30907, Nucrel® 31001, Nucrel® 3990, and Nucrel® AE (manufactured by DuPont). Other specific examples of ethylene ethylene-acrylic acid (EAA) based copolymers include Escor™ 5000, Escor™ 5020, Escor™ 5050, Escor™ 5080, Escor™ 5100, Escor™ 5200, and Escor™ 6000 (manufactured by ExonMobile Chemical).

[0082] Other more suitable impact modifiers include ionomers of ethylene acid copolymers. Specific examples of such impact modifiers include Surlyn® 1601, Surlyn® 1601-2, Surlyn® 1601-2LM, Surlyn® 1605, Surlyn® 8150, Surlyn® 8320, Surlyn® 8528, and Surlyn® 8660 (manufactured by DuPont).

[0083] In another embodiment, the impact modifier is an alkyl methacrylate-silicone / alkyl acrylate graft copolymer. The "alkyl methacrylate" in the graft copolymer may be selected from the group consisting of 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 silicone monomers and alkyl acrylate monomers. The silicone monomer may be selected from the group consisting of dimethylsiloxane, hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, trimethyltriphenylcyclotetrasiloxane, tetramethyltetraphenylcyclotetrasiloxane, and octaphenylcyclotetrasiloxane. The alkyl monomer may be selected from the group consisting of 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 graft ratio of 5 to 90% (wt / wt), a core glass transition temperature of -150 to -20°C, and a shell glass transition temperature of 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. of Japan.

[0084] Other suitable impact modifiers include the siloxane polymers mentioned in US Pat. No. 4,616,064, which contain siloxane units and at least one carbonate, urethane or amide unit.

[0085] Suitable impact modifiers also include those mentioned in WO2018 / 089573, paragraphs

[0043] to

[0072] .

[0086] Other suitable impact modifiers include core-shell impact modifiers such as those mentioned in US Pat. No. 5,409,967.

[0087] Resins including recycled ABS polymers may also include fillers. Suitable examples of fillers include inorganic particulate materials, nanocomposites, or mixtures thereof.

[0088] Suitable examples of inorganic particulate materials include inorganic oxides such as glass, MgO, SiO, TiO, and SbO; hydroxides such as Al(OH) and Mg(OH); salts such as CaCO, BaSO, CaSO, and phosphates; silicates such as talc, mica, kaolin, wollastonite, montmorillonite, nanoclays, feldspar, and asbestos; metals such as boron and steel; carbon-graphites such as carbon fibers, graphite fibers and flakes, carbon nanotubes, and carbon black. Suitable examples of inorganic particulate materials also include surface-treated and / or surface-modified SiO and TiO, such as alumina-surface-modified TiO.

[0089] Suitable examples of 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, epoxy / clay nanocomposites, polypropylene (PP) / clay nanocomposites, poly(methyl methacrylate) (PMMA) / clay nanocomposites and polyvinyl chloride (PVC) / clay nanocomposites; alumina-filled polymers, such as epoxy / alumina nanocomposites, PMMA / alumina nanocomposites, PI / alumina nanocomposites, PP / alumina nanocomposites, LDPE / alumina nanocomposites, and polyvinyl chloride (PVC) / clay nanocomposites. These include lumina nanocomposites and cross-linked 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, epoxy / 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, epoxy / zinc oxide nanocomposites, and PMMA / zinc oxide nanocomposites.

[0090] Resins containing recycled ABS polymers may also contain antioxidants. Suitable examples of antioxidants include phosphites, phenols, amines, and any mixtures thereof.

[0091] Resins containing recycled ABS polymers may also contain a lubricant. The addition of a lubricant can be crucial to obtaining 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, montan wax, paraffin wax, polyethylene wax, polypropylene wax, silicone-based lubricants, and mixtures thereof.

[0092] Resins containing recycled ABS polymers may also contain flame retardants. Suitable examples of flame retardants include inorganic flame retardants such as magnesium or aluminum hydroxide, organic flame retardants such as carboxylic acids and organophosphorus flame retardants.

[0093] Resins containing recycled ABS polymers may also contain colorants. Suitable examples of colorants include organic pigments, inorganic pigments, oil-soluble dyes, zinc ferrite, carbon black, titanium dioxide, and aluminum oxide.

[0094] Resins containing recycled ABS polymers may also contain light stabilizers and / or UV absorbers. Suitable examples of light stabilizers / UV absorbers include benzoates, benzophenones, benzotriazoles, hindered amines, and triazines.

[0095] Resins containing recycled ABS polymers may also contain plasticizers. Suitable examples of plasticizers include hydrocarbon processing oils, phosphate esters such as triphenyl phosphate and resorcinol bis(diphenyl phosphate) or oligomeric phosphates, long chain fatty acids, and aromatic sulfonamides.

[0096] The type and assortment of ABS scrap is important to the uniformity of the ABS polymer in the resin. The more uniform the scrap, the more uniform the resin. It is advantageous to use a resin with recycled ABS polymer of uniform length and crosslinking, as well as butadiene sphere size. In one embodiment, the recycled ABS polymer is produced from ABS scrap from the toy industry.

[0097] In a preferred embodiment, the ABS waste material is discarded toy building elements. The main advantage of using discarded toy building elements from a manufacturer's own production plant is that its chemical composition is known, and it is also known how to process the material. If the waste material is color-coded before recycling, it may be easier to produce recycled toy building elements with a uniform color. If the waste material is not color-coded before recycling, it may be necessary to first remove colorant and then add new colorant to obtain a final toy building element with a satisfactory color.

[0098] Some ABS waste materials contain harmful additives that are therefore unacceptable for their presence in recycled ABS materials when used to manufacture toys, e.g., toy building blocks. 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 continued degradation of the ABS material during the life of the item before it is discarded as waste.

[0099] In general, recycled ABS materials 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 material will not be suitable for use in the manufacture of toy building elements.

[0100] In detail, the amount of substances classified as carcinogenic, mutagenic, or toxic to reproduction (CMR) in Category 1A, 1B, or 2 under Regulation (EC) No. 1272 / 2008 must be below the specified limit range. Thus, the total content of Category 1A and 1B carcinogens must be less than 1,000 ppm, while the total content of Category 2 carcinogens must be less than 10,000 ppm. The total content of Category 1A and 1B mutagens must be less than 1,000 ppm, while the total content of Category 2 mutagens must be less than 10,000 ppm. The total content of Category 1A and 1B reproductive toxicants must be less than 3,000 ppm, while the total content of Category 2 reproductive toxicants must be less than 30,000 ppm.

[0101] It is also important that the metal content in ABS waste material is below the migration limits specified, for example, in the Toy Safety Directive (2009 / 48 / EC), otherwise the waste material is not suitable for use in the manufacture of toy building elements. In detail, the following migration limits must not exceed: aluminum: 70,000 mg / kg, antimony: 560 mg / kg, arsenic: 47 mg / kg, barium: 18,750 mg / kg, boron: 15,000 mg / kg, cadmium: 17 mg / kg, chromium(III): 460 mg / kg, chromium(IV): 0.053 mg / kg, cobalt: 130 mg / kg, copper: 7,700 mg / kg, lead: 160 mg / kg, manganese: 15,000 mg / kg, mercury: 94 mg / kg, nickel: 930 mg / kg, selenium: 460 mg / kg, strontium: 56,000 mg / kg, tin: 180,000 mg / kg, organotins: 12 mg / kg, and zinc: 46,000 mg / kg.

[0102] To achieve uniform physical and chemical properties and non-hazardous ABS waste, it may be beneficial or even necessary to screen the waste prior to recycling. Such screening may include analytical methods to quantify the butadiene copolymer to SAN ratio, to detect and / or quantify carcinogens, mutagens, reproductive toxicants, antioxidants, heavy metals, halides, lubricants, flame retardants, colorants, etc. Suitable analytical methods may include attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) to determine the butadiene copolymer to SAN ratio, thermogravimetric analysis (TGA) and / or differential scanning calorimetry-oxidation induction time (DSC-OIT) to determine the thermal oxidative stability of the waste, and X-ray fluorescence spectroscopy (XRF) to determine the amount of heavy metals and / or halides, etc. It may also be necessary to screen the ABS waste for the size of butadiene spheres and to investigate whether 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 techniques include measuring the gloss of the remolded parts.

[0103] The present invention also relates to a method for manufacturing toy building elements, which method is illustrated in Figure 2. The method comprises: a) preparing and screening ABS waste material; b) subjecting the ABS waste material of step a to a crushing and / or solvent dissolution recycling process to recover recycled ABS polymer from the screened ABS waste material; 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 the group consisting of virgin ABS polymers, chemically recycled ABS polymers recovered from pyrolysis, and chemically recycled ABS polymers recovered from chemical depolymerization; d) manufacturing toy building elements by processing the resin of step c. Includes:

[0104] Suitable resins obtained in step c and processed in step d include those described above.

[0105] The recycled ABS polymer in the resin comes from ABS waste material, which is subjected to one or more screening processes before being incorporated into the resin, so that only materials that are not harmful and / or contain acceptable additives are incorporated into the resin.

[0106] In step a, the ABS waste material: - the amount of substances classified as carcinogenic, mutagenic or toxic for reproduction (CMR) in category 1A, 1B or 2 under Regulation (EC) No 1272 / 2008, - migration limits of one or more metals selected from the group consisting of aluminum, antimony, arsenic, barium, boron, cadmium, chromium (III), chromium (IV), cobalt, copper, lead, manganese, mercury, selenium, strontium, tin, organotin and zinc; - amount of oxide, - amount of phthalates, - amount of flame retardant, - the ratio of butadiene copolymer to SAN, - the size and size distribution of the butadiene spheres, and - the level of crosslinking of the butadiene spheres.

[0107] It is crucial that the amount of substances classified as carcinogenic, mutagenic, or toxic to reproduction (CMR) in Category 1A, 1B, or 2 under Regulation (EC) No. 1272 / 2008 is below the specified limits; otherwise, the waste material is not suitable for use in manufacturing toys. Therefore, the total content of Category 1A and 1B carcinogens must not exceed 1,000 ppm, while the total content of Category 2 carcinogens must not exceed 10,000 ppm. The total content of Category 1A and 1B mutagens must not exceed 1,000 ppm, while the total content of Category 2 mutagens must not exceed 10,000 ppm. The total content of Category 1A and 1B reproductive toxicants must not exceed 3,000 ppm, while the total content of Category 2 reproductive toxicants must not exceed 30,000 ppm.

[0108] It is also important that the metal content in ABS waste material is below the migration limits specified, for example, in the Toy Safety Directive (2009 / 48 / EC), otherwise the waste material is not suitable for use in the manufacture of toy building elements. In detail, the following migration limits must not be exceeded: aluminum: 70,000 mg / kg, antimony: 560 mg / kg, arsenic: 47 mg / kg, barium: 18,750 mg / kg, boron: 15,000 mg / kg, cadmium: 17 mg / kg, chromium(III): 460 mg / kg, chromium(IV): 0.053 mg / kg, cobalt: 130 mg / kg, copper: 7,700 mg / kg, lead: 160 mg / kg, manganese: 15,000 mg / kg, mercury: 94 mg / kg, nickel: 930 mg / kg, selenium: 460 mg / kg, strontium: 56,000 mg / kg, tin: 180,000 mg / kg, organotins: 12 mg / kg, and zinc: 46,000 mg / kg.

[0109] This amount of iron oxide must also be kept at an extremely low level to avoid chemical degradation of the ABS polymer over time, specifically to avoid the formation of ABS monomers that would impair the mechanical properties of the toy building elements produced and therefore constitute a product safety issue. When ABS scrap is used in the manufacture of toys, this amount of toxic compounds, such as phthalates and flame retardants, must also be avoided.

[0110] It is also important that the waste ABS material is screened for butadiene copolymer to SAN ratio and butadiene sphere size. The butadiene content in the ABS material is preferably in the range of 15-22 wt% of the total ABS polymer. To obtain a glossy surface for the toy building elements produced, the butadiene sphere size is preferably 0.5 micrometers or less.

[0111] In some cases, the waste ABS material can be highly heterogeneous, and in such cases, it may be necessary to sort the waste ABS material before screening for the properties mentioned above.

[0112] In step b, the screened ABS waste material is subjected to a crushing and / or solvent dissolution recycling process to recover recycled ABS polymer.

[0113] A method for producing toy building elements by mechanically processing resin containing recycled ABS polymer is shown in Figures 3 and 4. In this method, screened ABS waste is subjected to grinding. In the grinding step, the recycled material is crushed / cut into small pieces of material. This step is important to obtain a homogeneous mixture of materials that can be easily mixed with additives and, optionally, other ABS polymers, and easily melted during the production of the toy building elements, i.e., by injection molding, extrusion, or additive manufacturing processes.

[0114] A method for manufacturing toy building elements by processing resins containing chemically recycled ABS polymer is shown in Figures 5, 6, and 7. In this method, screened ABS waste is subjected to a solvent dissolution recycling process. Typically, the waste ABS material is ground prior to dissolution to facilitate dissolution of the waste, although the grinding step is not required. During the dissolution step, the ABS waste is dissolved and the ABS polymer separates into two phases: one phase contains poly(styrene-co-acrylonitrile) chains, also known as the SAN phase, and the other phase contains butadiene copolymer, also known as butadiene spheres. In some embodiments, both the SAN phase and the butadiene spheres are recycled (Figure 5), while in other embodiments, only the SAN phase is recycled (Figures 6 and 7).

[0115] 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 mixed with the recycled ABS polymer and, optionally, the virgin and / or virgin-like ABS polymer may also be mixed 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 polymer may be a bio-based ABS polymer and / or a hybrid bio-based polymer. Furthermore, the virgin-like ABS polymer may be an ABS polymer recovered from a chemical pyrolysis recycling process or a chemical depolymerization recycling process.

[0116] In particular preferred embodiments, the waste ABS material is discarded toy building elements, as shown in Figure 4. In these embodiments, the addition of additives may not be necessary because the discarded toy building elements may already possess the mechanical properties necessary to produce toy building elements with the required properties.

[0117] In step d, toy building elements are produced by processing the resin obtained in step c. In some embodiments, the toy building elements are produced by injection molding. In such embodiments, mixing the recycled ABS polymer with additives and / or colorants, and optionally additional virgin or virgin-like ABS polymer, can occur before feeding the resin into an injection molding machine. In some embodiments, mixing can occur as a dry mixing step or a compounding step. In other embodiments, mixing can occur by using a compounding step in an extruder prior to the injection molding step. In still other embodiments, the additives can be mixed into a masterbatch, which is then mixed with the remainder of the ABS resin during feeding of the injection molding machine. Alternatively, mixing can occur during feeding of the resin into the injection molding machine.

[0118] In yet other embodiments, the toy building elements are manufactured by extrusion, optionally followed by molding using thermoforming or similar techniques.

[0119] In some embodiments, the toy building elements are manufactured by additive manufacturing. Suitable examples of additive manufacturing techniques are those in which the toy building elements are assembled by photopolymerization additive manufacturing or thermoplastic additive manufacturing, such as liquid-based additive manufacturing, toner-based additive manufacturing, powder-based additive manufacturing, or granule-based additive manufacturing.

[0120] Preferably, the method also includes subjecting the resin obtained in step c to quality control before manufacturing the resin into toy building elements in step d. The quality control is primarily to verify the key mechanical properties necessary to obtain final toy building elements with the required properties. Examples of mechanical properties that are typically measured include one or more of impact strength, surface friction, surface gloss and color.

[0121] Example The following examples describe how ABS can be recycled by regrindting the molded components and runners and then using this regrind to produce new components by injection molding. In Example 1, all ABS material is recycled, and in Example 2, the recycled ABS is mixed with virgin ABS before injection molding new components. The impact strength of the injection-molded components is tested using the Charpy v-notch test.

[0122] Charpy V-notch test Dimensions: 6.0 x 4.0 x 50.0 mm 3 Molded plastic bars of dimensions B x W x H and of the relevant material to be tested were cut with a notch cutter (ZNO, Zwick, Germany) with a notch tip diameter of 0.5 mm according to ISO 179-1 / 1 eA. The notched specimens were placed with the v-notch on the opposite side of the pendulum and tested in a pendulum impact tester (HOT, Zwick, Germany) according to the principles described in ISO 179-1:2010. [Example]

[0123] Properties of ABS from Mechanical Recycling - Complete Recycling of ABS Virgin ABS Terluran® GP35 (supplied by INEOS Styrolution) was dried at 80°C for 4 hours. The ABS was processed into impact specimens and runners via injection molding (Arburg, Allrounder 470E 1000-400, 30mm screw, Germany). Ten impact specimens were tested in a Charpy v-notch test, and the results are recorded as 0 regrind cycles in the table below.

[0124] The remaining runners and impact specimens were re-ground into pellets in a plastics crusher. The crushed ABS pellets were re-processed into impact specimens and runners, and 10 impact specimens were used in Charpy v-notch tests, with the results recorded as one re-grind cycle. In a similar manner, the remaining impact specimens and runners were crushed and re-processed for up to 10 re-grind cycles.

[0125] The injection molding parameters were as follows: Melting temperature: 240℃ Mold temperature: 30℃

[0126] The results are shown in the table below. [Table 1]

[0127] The results show that one regrinding cycle does not appear to affect the Charpy v-notch at all, but five regrinding cycles reduce the relative Charpy v-notch value from 100 to 95. Such a reduction would still be acceptable for toy building element production. A further reduction in relative Charpy v-notch to 88 is seen after 10 regrinding cycles. This indicates that toy building elements made from 10-times recycled ABS may very well possess unacceptable mechanical properties due to insufficient impact strength. Therefore, new or additional impact modifiers need to be blended into the recycled material to improve impact strength to an acceptable level. [Example]

[0128] Properties of ABS from Mechanical Recycling - Partial Recycling of ABS Two molds producing elements of different sizes were used to test the effect of applying various amounts of mechanically recycled ABS in the molding process. In this study, the amount of mechanically recycled ABS was represented by the percentage of the mechanically regrind runner system reintroduced into the ABS molding process. The two molds tested were constructed to allow 42% and 90% regrind to flow through the runners during the molding process. These two molds were used to investigate whether supplementing various levels of virgin ABS with regrind could help maintain good overall impact properties of molded elements. These two molds were used to generate input material for three additional molds, each flowing 37%, 51%, and 85% regrind, respectively.

[0129] Virgin ABS Terluran® GP35 (supplied by INEOS Styrolution) was dried at 80°C for 4 hours. The ABS was processed into LEGO elements via injection molding (Arburg, Allrounder 470 E 1000-400, 30mm screw, Germany) using molds no. 1 and 2. The molds were fed with regrind and virgin ABS according to the table below. Due to the level of regrind introduced into the process, the mold needs to produce several shots before the overall process stabilizes, i.e., before a steady-state situation is achieved. The number of shots to ensure a stable process is indicated in the table below. [Table 2]

[0130] Once stable processing was achieved, mold-ready blend material samples were collected and processed into impact specimens via injection molding. The molded impact specimens were used for Charpy v-notch analysis, the results of which are shown in the table below.

[0131] The stable processed material produced in molds 1 and 2 was further used as input material for processing in molds 3, 4, and 5. Once stable processing was achieved, material samples were collected and used to produce impact specimens that were tested with Charpy v-notch analysis. The results are shown in the table below. [Table 3]

[0132] The results show that adding a certain amount of mechanically recycled ABS to virgin ABS in the molding process unexpectedly increases the relative Charpy v-notch value. Specifically, mold 1, which flows with 42% regrind, shows an increase in relative Charpy v-notch value of up to 108%. Furthermore, when the steady-state material from mold 1 is used as the input material for mold 3, the relative Charpy v-notch value further increases to 112% compared to the use of virgin material. The inventors have observed such an increase in relative Charpy v-notch value several times, which may indicate improved dispersion of polybutadiene spheres when recycled ABS material is mixed with virgin ABS.

[0133] The results also show that as the number of recycling cycles of ABS increases, the relative Charpy v-notch value decreases, resulting in molded components with reduced impact strength. The exact Charpy v-notch value that is acceptable when using recycled ABS to produce toy building components depends on the type of component being produced; for example, a traditional LEGO® brick requires higher impact strength than a LEGO® DUPLO® brick. Ultimately, however, independent of component type, recycled ABS material can no longer produce toy building blocks with satisfactory mechanical properties, and new or additional impact modifiers or virgin ABS must be blended with the recycled ABS to produce toy building components with acceptable impact strength.

[0134] The above experimental results indicate that ABS can be mechanically recycled to some extent, but ultimately, an improvement in the mechanical properties is required to produce toy building elements with acceptable mechanical properties, e.g., acceptable impact strength.

Claims

1. Toy building elements made from recycled ABS (acrylonitrile butadiene styrene) material and manufactured by mechanically processing a resin containing recycled ABS polymer.

2. The toy building element of claim 1 , wherein the resin further comprises a virgin ABS polymer.

3. The resin meets the requirements specified in Regulation (EC) No 1907 / 2006 and Toy Safety Directive (2009 / 48 / EC) and the criteria for the amount of substances classified as carcinogenic, mutagenic or toxic for reproduction (CMR) in category 1A, 1B or 2 under Regulation (EC) No 1272 / 2008: The total content of carcinogens in categories 1A and 1B is 1000 ppm or less, The total content of Category 2 carcinogens is 10,000 ppm or less, The total content of mutagens in categories 1A and 1B is 1000 ppm or less; The total content of Category 2 mutagens is 10,000 ppm or less; The total content of substances classified as Category 1A and 1B as reproductive toxicants is 3000 ppm or less; The total content of Category 2 reproductive toxic substances is 30,000 ppm or less and meets the migration limits of metal content specified in the Toy Safety Directive (2009 / 48 / EC): Aluminum: 70,000 mg / kg or less, Antimony: 560 mg / kg or less, Arsenic: 47 mg / kg or less, Barium: 18,750 mg / kg or less, Boron: 15,000 mg / kg or less, Cadmium 17 mg / kg or less, Chromium (III): 460 mg / kg or less, Chromium (IV): 0.053 mg / kg or less, Cobalt: 130 mg / kg or less, Copper: 7700mg / kg or less, Lead: 160mg / kg or less, Manganese: 15,000 mg / kg or less, Mercury: 94mg / kg or less, Nickel: 930 mg / kg or less, Selenium: 460 mg / kg or less, Strontium: 56,000 mg / kg or less, Tin: 180,000 mg / kg or less, Organotins: not more than 12 mg / kg; and Zinc: 46,000 mg / kg or less 3. The toy building element according to claim 1, wherein:

4. 4. The toy building element of claim 1, wherein the toy building element is manufactured by injection molding, extrusion or additive manufacturing techniques, or by a combination of injection molding and additive manufacturing techniques.

5. 5. The toy building element of claim 1, wherein the mechanically recycled ABS polymer comprises butadiene spheres having a size of 0.5 micrometers or less.

6. 3. The toy building element of claim 2, wherein the weight ratio between the mechanically recycled ABS polymer and the virgin ABS polymer ranges from 100:0 to 5:

95.

7. 7. The toy building element of claim 1, wherein the resin comprises, in part, a bio-based ABS polymer, and / or a hybrid bio-based ABS polymer, and / or an ABS polymer produced using carbon capture technology.

8. 8. A toy building element according to any one of claims 1 to 7, wherein the total amount of ABS polymer in the resin is at least 50 wt% relative to the total weight of the resin.

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

10. 10. The toy building element of any one of claims 1 to 9, wherein the mechanically recycled ABS polymer is produced from ABS waste material from the toy industry.

11. 11. The toy building element of claim 10, wherein the ABS waste material is discarded toy building elements.

12. 12. A toy building element according to any one of claims 1 to 11, produced by injection moulding using a mould that flows 20-95 wt% recycled material after steady state.

13. a) providing and screening ABS waste material; b) subjecting the ABS waste screened in step a to a crushing process to recover recycled ABS polymer from the ABS waste; c) blending the ABS polymer recovered in step b with one or more additives, and optionally with virgin ABS polymer, to obtain a resin; d) manufacturing toy building elements by processing the resin obtained in step c; 1. A method for manufacturing a toy building element, comprising:

14. The ABS scrap material comprises: - the amount of substances classified as carcinogenic, mutagenic or toxic for reproduction (CMR) in category 1A, 1B or 2 under Regulation (EC) No 1272 / 2008, - migration limits of one or more metals selected from the group consisting of aluminum, antimony, arsenic, barium, boron, cadmium, chromium (III), chromium (IV), cobalt, copper, lead, manganese, mercury, selenium, strontium, tin, organotin and zinc; - amount of oxide, - amount of phthalates, - amount of flame retardant, - butadiene copolymer to SAN ratio, - butadiene sphere size and size distribution, and - the level of crosslinking of the butadiene spheres.

15. 15. The method of claim 13 or 14, wherein the ABS polymer recovered in step b is compounded with one or more additives selected from the group consisting of impact modifiers, fillers, antioxidants, lubricants, flame retardants, colorants, light stabilizers / UV absorbers, and plasticizers.

16. 16. The method according to any one of claims 13 to 15, wherein the toy building elements are 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.

17. 17. A method according to any one of claims 13 to 16, wherein the resin obtained in step c is subjected to quality control before being manufactured into toy building elements in step d.

18. The quality control includes measuring one or more physical properties of the resin, the physical properties being: - impact strength, - surface friction, - surface gloss, and - color.

19. 19. The method of any one of claims 13 to 18, wherein the ABS waste material is discarded toy building blocks, and wherein in step c) it is optional to mix the ABS polymer recovered in step b) with one or more additives.

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