Patent Application
20240182674
The present invention relates to an innovative stabilizer composition for stabilizing halogen-free thermoplastic plastic recyclates. In addition, the present invention relates to a stabilizer composition, a master batch or a concentrate, a stabilized plastic composition, a method of stabilizing halogen-free thermoplastic plastic recyclates, and to possible uses of the composition.
Plastic recyclates are a growing market and an important element in recycling management of natural resources, with recyclates ideally being intended to replace new plastics having an identical or at least comparable property profile. Recyclates from the production of plastic parts (so-called “postindustrial” recyclates) and from collections of old plastics (so-called “post-consumer recyclates), however, differ chemically from new plastic products. Irreversible changes in the polymer chains result during the first processing steps (e.g. by compounding, extrusion, or injection molding) and during use frequently over many years and in demanding areas of application (e.g. high temperatures and/or UV light) due to mechano-chemical, chemical, or light-induced processes (see e.g. R. Pfaendner et al., Anew. Makromol. Chemie 1995, 232, 193-227, R. Pfaendner, Kunststoffe International 12/2015, 41-44, J. Pospisil et al., Pol. Degr. Stab. 1995, 48, 351-358, F. P. La Mantia, Macromol. Symp. 1998, 135, 157-165,).
New chemical groups are produced in the polymer chain and/or the composition of the polymers is changed on the molecular level by radical reactions in the presence of oxygen. The chemical changes produced by the damage process and by the aging process are above all hydroperoxide groups, aliphatic carbonyl groups, alpha-beta unsaturated carbonyl groups, alcohol groups, acid groups, ester groups, and peroxy acid groups, i.e. structures that, for example, are typically not present in new polyolefin products and are above all produced as a consequence of oxidation processes (J. Pospisil et al. Macromol. Symp. 1998, 135, 247-263). Furthermore, recyclates in particular comprise polyolefins, frequently unsaturated structures, i.e. vinylide groups, vinylene groups, and vinyl groups, wherein vinylene groups can even be present in conjugated form. Unsaturated structures are produced here by chain splitting reactions and disproportionation reactions (H. Hjnske et al., Pol. Degr. Stab. 1991, 34, 279-293,). The concentration of these newly formed groups increases with the processing intensity (process management, shear, temperature), the area of use (UV light, high temperatures, contact media), and the time of use. Furthermore, the formation of these structures in oxidation processes and consecutive reactions can be catalyzed by metals and by pigments. The structural inhomogeneities of a recyclate consequently influence the plastic properties such as the mechanical properties or the morphology. Recyclates or predamaged plastics are more sensitive to oxidation than as new material due to the newly formed chemical structures since they act as initiator sites for a further oxidation or as prodegrants (A. S. Maxwell, Pol. Eng. Sci. 2008, 48, 381-385, I. H. Craig, J. R. White, J. Mater. Sci. 2006, 41, 993-1006, S. Luzuriaga et al. Pol. Degr. Stab. 2006, 91, 1226-1232). It is furthermore documented that the degradation rate depends on the concentration of the chromophoric “contaminants” (M. S. Rabello, J. R. White, Polym. Degrad. Stab. 1997, 56, 55-73). The concentrations of the described “aging” structures in the recyclates can increase by several orders of magnitude with respect to the new material. It is furthermore known that even small portions of old plastics in mixtures with new products result in a disproportional property degradation (V. S. Cecon et al., Polym. Degr. Stab. 2021, 190. 109627).
Post-stabilization with selected stabilizers such as antioxidants is an important method to achieve a quality improvement of plastic recyclates. The stabilizers used protect the recyclate from further oxidative (or photo-oxidative) damage or at least delay it. Since new plastic products and plastic recyclates, as described, differ significantly chemically and since recyclates are more oxidation sensitive due to this predamage and imitator sites, it is a challenging object to develop powerful stabilizers for an efficient stabilization of plastic recyclates that is distinguished from the new product due to the described structural differences of the recyclate.
Due to the differences now recognized between new plastic products and plastic recyclates, special recyclate stabilizer compositions have become known and are also available as commercial products (e.g. the Recyclobyk products of BYK Chemie GmbH, Wesel). Known technical stabilization solutions that take account of the demands of recyclates are, for example: described in the following patents/patent applications, for example:
Stabilization composition consisting of a phenolic antioxidant, a phosphite, and a metal oxide such as calcium oxide (U.S. Pat. Nos. 6,525,158, 6,251,972).
Stabilization composition consisting of a phenolic antioxidant and a polyfunctional epoxide (EP 0702704).
Stabilization by a macrocyclic piperidine (U.S. Pat. No. 5,789,470).
Stabilization composition consisting of a secondary aromatic amine and a polyfunctional epoxide (WO 97/30112).
Discoloration of damaged polyolefins by a hydroxylamine (EP 0470048).
Mixture of antioxidants, mold lubricants, anti-blocking agents, UV stabilizers, and antistatic agents for recyclate films (DD 288161).
Stabilization composition for mixed plastics consisting of a phenolic antioxidant and a phosphite/phosphonite (EP 0506614).
The following applications of the applicant for the stabilization of recyclates are furthermore present:
Inorganic sulfites have e.g. been proposed in the form of calcium sulfite or lead sulfite as stabilizers for polymers comprising halogens such as PVC (e.g. EP 313113, U.S. Pat. No. 3,542,725, US20030104954) and for polyvinylpyrrolidone (U.S. Pat. No. 2,872,433, DE102005005974), but have not yet been described for the thermal stabilization of plastic recyclates. Organic esters of sulfurous acid are generally known for the stabilization of polymers (e.g. DD 247913, U.S. Pat. No. 3,542,725), but not for the stabilization of plastic recyclates.
Despite the known solutions for the post-stabilization of recyclates, there is still a demand for particularly high performance, environmentally friendly, and inexpensive stabilizer compositions for recyclates that are obtained from the compositions in accordance with the invention of inorganic sulfites and primary antioxidants.
This object is satisfied by the features of the independent claims. The dependent claims in this respect set forth advantageous further developments.
The invention thus relates in a first aspect to the use of at least one stabilizer composition comprising or consisting of
New stabilizer compositions and a new method of stabilizing in particular plastic recyclates are proposed that have high effectiveness, environmental friendliness, and a favorable cost structure.
A preferred embodiment provides that the at least one sulfite is an inorganic sulfite, an inorganic disulfite, or an inorganic hydrogen sulfite, preferably a monovalent, bivalent, trivalent, or tetravalent metal, with the metal preferably being an alkali metal, an alkaline earth metal, aluminum, and/or zinc, particularly preferably a sulfite selected from the group consisting of sodium sulfite, potassium sulfite, lithium sulfite, calcium sulfite, magnesium sulfite, aluminum sulfite, zinc sulfite, or an organic sulfite, and mixtures and combinations thereof, with the sulfite in particular being used in its form free of crystal water; and/or
The primary antioxidant is preferably selected from the group consisting of H donors, radical scavengers, phenolic antioxidants, (partially) aromatic amines, hydroxylamines, or N-oxides (nitrones), and lactones.
Preferred phenolic antioxidants are here selected from the group consisting of Alkylated monophenols, such as 2,6-di-tert-butyl-4-methylphenol, 2-tert-butyl-4,6-dimethylphenol, 2,6-di-tert-butyl-4-ethylphenol, 2,6-di-tert-butyl-4-n-butylphenol, 2,6-di-tert-butyl-4-isobutyl phenol, 2,6-dicyclopentyl-4-methylphenol, 2-(α-methylcyclohexyl)-4,6-dimethylphenol, 2,6-dioctadecyl-4-methylphenol, 2,4,6-tricyclohexylphenol, 2,6-di-tert-butyl-4-methoxymethylphenol, linear or branched nonylphenols such as 2,6-dinonyl-4-methylphenol, 2,4-dimethyl-6-(1′-methylundec-1′-yl)phenol, 2,4-dimethyl-6-(1′-methylheptadec-1′-yl)phenol, 2,4-dimethyl-6-(1′-methyltridec-1′-yl)phenol and mixtures thereof;
Further particularly preferred phenolic antioxidants are tocopherols (vitamin E), tocotrienols, tocomonoenols, hydroxytyrosol, flavanols such as chrysin, quercitin, hesperidin, neohesperidin, naringin, morin, kaempferol, fisetin, and tannins, vitamin E (tocopherol) is very particularly preferred.
Preferred usable amine antioxidants are selected from the group consisting of N,N′-di-isopropyl-p-phenylene diamine, N,N′-di-sec-butyl-p-phenylene diamine, N,N′-bis(1,4-dimethyl pentyl)-p-phenylene diamine, N,N′-bis(1-ethyl-3-methyl pentyl)-p-phenylene diamine, N,N′-bis(1-methyl heptyl)-p-phenylene diamine, N,N′-dicyclohexyl-p-phenylene diamine, N,N′-diphenyl-p-phenylene diamine, N,N′-bis(2-naphthyl)-p-phenylene diamine, N-isopropyl-N′-phenyl-p-phenylene diamine, N-(1,3-dimethyl butyl)-N′-phenyl-p-phenylene-diamine, N-(1-methyl heptyl)-N′-phenyl-p-phenylene diamine, N-cyclohexyl-N′-phenyl-p-phenylene diamine, 4-(p-toluolsulfamoyl)diphenylamine, N,N′-dimethyl-N,N′-di-sec-butyl-p-phenylene diamine, diphenylamine, N-allyl diphenylamine, 4-isopropoxydiphenylamine, N-phenyl-1-naphthylamine, N-(4-tert-octyl phenyl)-1-naphthylamine, N-phenyl-2-naphthylamine, octylated diphenylamine, e.g. p,p′-di-tert-octyl diphenylamine, 4-n-butyl aminophenol, 4-butyryl aminophenol, 4-nonanoyl aminophenol, 4-dodecanoyl aminophenol, 4-octadecanoyl amino-phenol, bis(4-methoxyphenyl)amine, 2,6-di-tert-butyl-4-dimethylaminomethyl-phenol, 2,4′-diamino diphenylmethane, 4,4′-diamino diphenylmethane, N,N,N′,N′-tetra-methyl-4,4′-diamino diphenylmethane, 1,2-bis[(2-methyl-phenyl)amino]ethane, 1,2-bis(phenylamino)propane, (o-tolyl)biguanide, bis[4-(1′,3′-dimethyl butyl)phenyl]amine, tert-octylated N-phenyl-1-naphthylamine, a mixture of monoalkylated and dialkylated tert-butyl/tert-octyldiphenylamines, a mixture of monoalkylated and dialkylated nonyldiphenylamines, a mixture of monoalkylated and dialkylated dodecyldiphenylamines, a mixture of monoalkylated and dialkylated isopropyl/isohexyl-diphenylamines, a mixture of monoalkylated and dialkylated tert-butyldiphenylamines, 2,3-dihydro-3,3-dimethyl-4H-1,4-benzothiazine, phenothiazine, a mixture of monoalkylated and dialkylated tert-butyl/tert-octylphenothiazines, a mixture of monoalkylated and dialkylated tert-octylphenothiazines, N-llylphenothiazine, N,N,N′,N′-tetraphenyl-1,4-diamino but-2-ene and mixtures or combinations hereof.
Preferred hydroxylamines or N-oxides (nitrones) are selected from the group consisting of N,N-dialkylhydroxylamines, N,N-dibenzyl hydroxylamine, N,N-dilaurylhydroxylamine, N,N-distearylhydroxylamine, N-benzyl-α-phenylnitrone, N-octadecyl-α-hexadecyl nitrone, and Genox EP (SI Group) in accordance with the formula:
For the purposes of the present invention, preferred lactones are selected from the group consisting of benzofuranones and indolinones, in particular selected from the group consisting of 3-(4-(2-acetoxyethoxy)phenyl]-5,7-di-tert-butyl-benzofuran-2-one, 5,7-di-tert-butyl-3-[4-(2-stearoyloxyethoxy)phenyl]benzofuran-2-one, 3,3′-bis[5,7-di-tert-butyl-3-(4-(2-hydroxy ethoxy]phenyl)benzofuran-2-one), 5,7-di-tert-butyl-3-(4-ethoxy phenyl)benzofuran-2-one, 3-(4-acetoxy-3,5-dimethylphenyl)-5,7-di-tert-butyl-benzofuran-2-one, β-(3,5-dimethyl-4-pivaloyloxyphenyl)-5,7-di-tert-butyl-benzofuran-2-one, β-(3,4-dimethylphenyl)-5,7-di-tert-butyl-benzofuran-2-one, 3-(2,3-dimethylphenyl)-5,7-di-tert-butyl-benzofuran-2-one as well as lactones that additionally comprise a phosphite group such as
It is equally possible to use mixtures and combinations of the aforesaid compounds.
The phenolic antioxidants selected from the group consisting of the following compounds are in particular preferred
Preferred aminic antioxidants are selected from the group consisting of the following compounds:
where n is 2 to 100.
With respect to the totality of the halogen-free thermoplastic plastic recyclates, the stabilizer composition will preferably use recyclates in a weight ratio of 0.01 to 10.00 wt %, preferably 0.02 to 5.00 wt %, and particularly preferably 0.05 to 2.00 wt %.
It is furthermore advantageous if the totality of the at least one sulfite and/or of the at least one thiosulfate and the totality of the at least one primary antioxidant is/are used in a weight ratio of 1:99 to 99:1, preferably 20:80 to 80:20, further preferably from 30:70 to 70:30, particularly preferably from 40:60 to 60:40.
The halogen-free thermoplastic plastic recyclates can in particular be recyclates of the polymers listed below:
The thermoplastic plastic recyclate is particularly preferably selected from the group consisting of polymers of olefins or diolefins such as polyethylene, in particular LDPE, LLDPE, VLDPE. ULDPE, MDE, HDPE, and UHMWPE, metallocene PE (m-PE), polypropylene, polyisobutylene, poly-4-methyl-pentene-1, polybutadiene, polyisoprene, polycyclooctene, polyalkylene-carbon monoxide copolymers, and corresponding copolymers in the form of statistical or block structures such as polypropylene-polyethylene (EP), EPM or EPDM, ethylene-vinyl acetate (EVA), ethylene-acrylic ester such as ethylene butyl acrylate, ethylene-acrylic acid glycidyl acrylate, and corresponding graft polymers such as polypropylene maleic acid anhydride, polypropylene-g-acrylic acid, and polyethylene acrylic acid.
The one thermoplastic is very particularly preferably a polyolefin recyclate. The thermoplastic plastic recyclate can, for example, be polypropylene, that is in particular a polypropylene recyclate homopolymer or copolymer, or polyethylene, that is in particular a polyethylene recyclate, e.g. HDPE, LDPE, LLDPE or mixtures of different polyethylenes such as HDPE, MDPE, LDPE, LLDPE or of PE and PP.
The stabilizer composition can be used in a further preferred embodiment in combination with at least one additive, in particular at least one additive selected from the group consisting of secondary antioxidants, UV absorbers, light stabilizers, metal deactivators, filler deactivators, antiozonants, nucleation agents, anti-nucleation agents, toughening agents, mold lubricants, rheological modifiers, thixotropic agents, chain extenders, processing aids, demolding aids, flame retardants, pigments, dyes, optical brighteners, antimicrobial active agents, antistatic agents, slip agents, anti-blocking agents, coupling agents, crosslinking agents, anti-cross-linking agents, hydrophilization agents, hydrophobing agents, bonding agents, dispersing agents, compatibilizers, oxygen scavengers, acid scavengers, expanding agents, degradation additives, defoaming agents, odor scavengers, marking agents, anti-fogging agents, fillers, reinforcement materials, polyol costabilizers, compatibilizers, and mixtures thereof.
In a preferred embodiment, the compositions in particular comprise light stabilizers, fillers, acid scavengers, polyol costabilizers, and/or compatibilizers.
Preferred fillers are calcium carbonate, silicates, talcum, mica, kaolin, metal oxides and metal hydroxides, black carbon, graphite, wood flour, or fibers of natural products such as cellulose. Further suitable fillers are hydrotalcites or zeolites or phyllosilicates such as montmorillonite, bentonite, beidellite, mica, hectorite, saponite, vermiculite, ledikite, magadiite, illite, kaolinite, wollastonite, attapulgite.
Suitable secondary antioxidants are in particular phosphites or phosphonites such as
Particularly preferred phosphites are:
where n=3-100
A preferred phosphonite is:
Suitable secondary antioxidants are furthermore organosulfur compounds such as sulfides and disulfides, e.g., distearylthiodipropionate, dilaurylthiodipropionate, ditridecyldithiopropionate, ditetradecylthiodipropionate, 3-(dodecylthio), 1,1′-[2,2-bis[[3-(dodecylthio)-I-oxopropoxy]methyl]1,3-propandiyl] propanoic acid ester. The following structures are preferred:
Suitable acid scavengers (“antacids”) are salts of monovalent, bivalent, trivalent, or quadrivalent metals, preferably alkali metals, alkaline earth metals, aluminum or zinc, in particular formed with fatty acids such as calcium stearate, magnesium stearate, zinc stearate, aluminum stearate, calcium laurate, calcium behenate, calcium lactate, calcium stearoyl-2-lactate. Further classes of suitable acid scavengers are hydrotalcites, in particular synthetic hydrotalcites on the basis of aluminum, magnesium and zinc, hydrocalumites, zeolites, alkaline earth metals, in particular calcium oxide and magnesium oxide and zinc oxide, alkaline earth carbonates, in particular calcium carbonate, magnesium carbonate and dolomite, and hydroxides, in particular brucite (magnesium hydroxide).
Suitable costabilizers are furthermore polyols, in particular alditols or cyclitols. Polyols are e.g. pentaerythritol, dipentaerythritol, tripentaerythritol, short chain polyether polyols or short chain polyester polyols, and hyperbranched polymers/oligomers, or dendrimers having alcohol groups e.g.
The at least one alditol is preferably selected from the group consisting of threitol, erythritol, galactol, mannitol, ribitol, sorbitol, xylitol, arabitol, ismaltol, lactitol, maltitol, altritol, iditol, maltotritol, and hydrated oligosaccharides and polysaccharides with polyol end groups and mixtures thereof. The at least one preferred alditol is particularly preferably selected from the group consisting of erythritol, mannitol, isomaltol, maltitol, and mixtures thereof.
Examples of further suitable sugar alcohols are heptitols and octitols: meso-glycero-allo-heptitol, D-glycero-D-altro-heptitol, D-glycero-D-manno-heptitol, meso-glycero-gulo-heptitol, D-glycero-D-galacto-heptitol (perseitol), D-glycero-D-gluco-heptitol, L-glycero-D-gluco heptitol, D-erythro-L-galacto-octitol, D-threo-L-galacto-octitol.
In particular, the at least one cyclitol may be selected from the group consisting of inositol (myo, scyllo-, D-chiro-, L-chiro-, muco-, neo-, allo-, epi- and cis-inositol), 1,2,3,4-tetrahydroxycyclohexane, 1,2,3,4,5-pentahydroxycyclohexane, quercitol, viscumitol, bornesitol, conduritol, ononitol, pinitol, pinpollitol, quebrachitol, ciceritol, quinic acid, shikimic acid and valienol; in this case myo-inositol is preferred.
Suitable light stabilizers are, for example, compounds based on 2-(2′-hydroxyphenyl) benzotriazoles, 2-hydroxy benzophenones, esters of benzoic acids, acrylates, oxamides, and 2-(2-hydroxyphenyl)-1,3,-5-triazines.
Suitable 2-(2′-hydroxyphenyl)benzotriazoles are, for example, 2-(2′-hydroxy-5′methylphenyl)benzotriazole, 2-(3′,5′-di-tert-butyl-2′-hydroxyphenyl)benzotriazole, 2-(5′-tert-butyl-2′-hydroxy-phenyl)benzotriazole, 2-(2′-hydroxy-5′-(1,1,3,3-tetramethylbutyl)phenyl)benzotriazole, 2-(3′,5′-di-tert-butyl-2′-hydroxyphenyl)-5-chlorobenzotriazole, 2-(3′-tert-butyl-2′-hydroxy-5′-methylphenyl-5-chlorobenzotriazole, 2-(3′-sec-butyl-5′-tert-butyl-2′-hydroxy-phenyl)benzotriazole, 2-(2′-hydroxy-4′-octyloxyphenyl)benzotriazole, 2-(3′,5′-di-tert-amyl-2′-hydroxyphenyl)benzotriazole, 2-(3′,5′-bis(α,α-dimethylbenzyl)-2′-hydroxyphenyl)benzotriazole, 2-(3′-tert-butyl-2′-hydroxy-5′-(2-octyloxycarbonylethyl)phenyl)-5-chlorobenzotriazole, 2-(3′-tert-butyl-5′-[2-(2-ethylhexyloxy)carbonylethyl]-2′-hydroxyphenyl)-5-chlorobenzotriazole, 2-(3′-tert-butyl-2′-hydroxy-5′-(2-methoxycarbonylethyl)phenyl)-5-chlorobenzotriazole, 2-(3′-tert-butyl-2′-hydroxy-5′-(2-methoxycarbonylethyl)phenyl)benzotriazole, 2-(3′-tert-butyl-2′-hydroxy-5′-(2-octyloxycarbonylethyl)phenyl)benzotriazole, 2-(3′-tert-butyl-5′-[2-(2-ethylhexyloxy)carbonylethyl]-2′-hydroxyphenyl)benzotriazole, 2-(3′-dodecyl-2′-hydroxy-5′-methylphenyl)benzotriazole, 2-(3′-tert-butyl-2′-hydroxy-5′-(2-isooctyloxycarbonylethyl)phenylbenzotriazole, 2,2′-methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-benzotriazole-2-ylphenol]; the product of the transesterification of 2-[3′-tert-butyl-5′-(2-methoxycarbonylethyl)-2′-hydroxyphenyl]-2H-benzotriazole with polyethyleneglycol 300; [R—CH2CH2—COO—CH2CH2—]-2, where R=3′-tert-butyl-4′-hydroxy-5′-2H-benzotriazole-2-ylphenyl, 2-[2′-hydroxy-3′-(α,α-dimethylbenzyl)-5′-(1,1,3,3-tetramethylbutyl)phenyl]benzotriazole, 2-[2′-hydroxy-3′-(1,1,3,3-tetramethylbutyl)-5′-(α,α-dimethylbenzyl)phenyl]benzotriazole.
Suitable 2-hydroxybenzophenones are, for example, 4-hydroxy-, 4-methoxy-, 4-octyloxy-, 4-decyloxy-4-dodecyloxy, 4-benzyloxy, 4,2′,4′-trihydroxy- and 2′-hydroxy-4,4′-dimethoxy derivatives of the 2-hydroxy benzophenones.
Suitable acrylates are, for example, ethyl-α-cyano-β,β-diphenylacrylate, isooctyl-α-cyano-β,β-diphenylacrylate, methyl-α-carbomethoxycinnamate, methyl-α-cyano-β-methyl-β-methoxycinnamate, butyl-α-cyano-β-methyl-β-methoxycinnamate, methyl-α-carbomethoxy-β-methoxycinnamate and N-(β-carbomethoxy-β-cyanovinyl)-2-methylindoline.
Suitable esters of benzoic acids are, for example, 4-tert-butylphenylsalicylate, phenylsalicylate, octylphenylsalicylate, dibenzoylresorcinol, bis(4-tert-butylbenzoyl)resorcinol, benzoylresorcinol, 2,4-di-tert-butylphenyl-3,5-di-tert-butyl-4-hydroxybenzoate, hexadecyl-3,5-di-tert-butyl-4-hydroxybenzoate, octadecyl-3,5-di-tert-butyl-4-hydroxybenzoate, 2-methyl-4,6-di-tert-butylphenyl-3,5-di-tert-butyl-4-hydroxybenzoate.
Suitable oxamides are, for example, 4,4′-dioctyloxyoxanilide, 2,2′-diethoxyoxanilide, 2,2′-dioctyloxy-5,5′-di-tert-butoxanilide, 2,2′-didodecyloxy-5,5′-di-tert-butoxanilide, 2-ethoxy-2′-ethoxanilide, N,N′-bis(3-dimethylaminopropyl)oxamide, 2-ethoxy-5-tert-butyl-2′-ethoxanilide and its mixtures with 2-ethoxy-2′-ethyl-5,4′-di-tert-butoxanilide, mixtures of o- and p-methoxy-disubstituted oxanilides and mixtures of o- and p-ethoxy-disubstituted oxanilides.
Suitable 2-(2-hydroxyphenyl)-1,3,5-triazines are, for example, 2,4,6-tris(2-hydroxy-4-octyloxyphenyl)-1,3,5-triazine, 2-(2-hydroxy-4-octyloxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-(2,4-dihydroxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2,4-bis(2-hydroxy-4-propyloxyphenyl)-6-(2,4-dimethylphenyl)-1,3,5-triazine, 2-(2-hydroxy-4-octyloxyphenyl)-4,6-bis(4-methylphenyl-1,3,5-triazine, 2-(2-hydroxy-4-dodecyloxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-(2-hydroxy-4-tridecyloxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-[2-hydroxy-4-(2-hydroxy-3-butyloxypropoxy)-phenyl]-4,6-bis(2,4-dimethyl)-1,3,5-triazine, 2-[2-hydroxy-4-(2-hydroxy-3-octyloxypropyloxy)phenyl]-4,6-bis(2,4-dimethyl)-1,3,5-triazine, 2-[4-(dodecyloxy/tridecyloxy-2-hydroxypropoxy)-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-[2-hydroxy-4-(2-hydroxy-3-dodecyloxypropoxy)phenyl]-4,6-bis(2,4-dimethylphenyl-1,3,5-triazine, 2-(2-hydroxy-4-hexyloxy)phenyl-4,6-diphenyl-1,3,5-triazine, 2-(2-hydroxy-4-methoxyphenyl)-4,6-diphenyl-1,3,5-triazine, 2,4,6-tris[2-hydroxy-4-(3-butoxy-2-hydroxypropoxy)phenyl]-1,3,5-triazine, 2-(2-hydroxyphenyl)-4-(4-methoxyphenyl)-6-phenyl-1,3,5-triazine, 2-{2-hydroxy-4-[3-(2-ethylhexyl-1-oxy)-2-hydroxypropyloxy]phenyl}-4,6-bis(2,4-dimethylphenyl-1,3,5-triazine.
Suitable metal deactivators are, for example, N,N′-diphenyloxamide, N-salicylal-N′-salicyloylhydrazine, N,N′-bis(salicyloyl)hydrazine, N,N′-bis(3,5-di-tert-butyl-4-hydroxyphenylpropionyl)hydrazine, 3-salicyloylamino-1,2,4-triazole, bis(benzylidene)oxalyldihydrazide, oxanilide, isophthaloyldihydrazide, sebacoyl-bis-phenylhydrazide, N,N′-diacetyladipoyldihydrazide, N,N′-bis(salicyloyl)oxylyldihydrazide, N,Ne-bis(salicyloyl)thiopropionyldihydrazide.
Particularly preferred as metal deactivators are
Suitable hindered amines are, for example 1,1-bis(2,2,6,6-tetramethyl-4-piperidyl)succinate, bis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacate, bis(1-octyloxy-2,2,6,6-tetramethyl-4-piperidyl)sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidyl)-n-butyl-3,5-di-tert-butyl-4-hydroxybenzylmalonate, the condensation product from 1-(2-hydroxyethyl)-2,2,6,6-tetramethyl-4-hydroxypiperidine and succinic acid, linear or cyclic condensation products of N,N′-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylene diamine and 4-tert-octylamino-2,6-dichloro-1,3,5-triazine, tris(2,2,6,6-tetramethyl-4-piperidyl)nitrilotriacetate, tetrakis(2,2,6,6-tetramethyl-4-piperidyl)-1,2,3,4-butane tetracarboxylate, 1,1′-(1,2-ethandiyl)-bis(3,3,5,5-tetramethylpiperazinone), 4-benzoyl-2,2,6,6-tetramethylpiperidine, 4-stearyloxy-2,2,6,6-tetramethylpiperidine, linear or cyclic condensation products of N,N′-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylene diamine and 4-morpholino-2,6-dichloro-1,3,5-triazine, the reaction product of 7,7,9,9-tetramethyl-2-cycloundecyl-1-oxa-3,8-diaza-4-oxospiro-[4,5]decane and epichlorhydrine.
The sterically hindered N—H, N-alkyl such as N-methyl or N-octyl, the N-alkoxy derivatives such as N-methoxy or N-octyloxy, the cycloalkyl derivatives such as N-cyclohexyloxy and the N-(2-hydroxy-2-methylpropoxy) analogs are also each included in the above-given structures here.
Preferred hindered amines furthermore have the following structures:
Preferred oligomeric and polymeric hindered amines have the following structures:
In the above-named compounds, n respectively means 2 to 100, preferably 3 to 20, particularly preferably 3 to 10.
A further suitable light stabilizer is Hostanox NOW (manufacturer: Clariant SE) having the following general structure:
where R is —O—C(O)—C15H31—O—C(O)—C17H35.
Compatibilizers are used, for example, with thermodynamically non-miscible blends or also with recyclate mixtures and comprise structural elements of the respective blend components that are mixed. Suitable compatibilizers for polyolefin mixtures are, for example, olefin block copolymers consisting of ethylene, propylene, and alpha-olefins such as 1-octene. Other compatibilizers, in particular for the compatibilization of polar plastics such as PET or polyamides, and non-polar plastics such as PP or PE polymers are, for example, polypropylene-g-maleic acid anhydride, polyethylene-g-maleic acid anhydride, polypropylene-g-acrylic acid, polyethylene-g-acrylic acid, poly(ethylene-co-maleic acid anhydride), SBS-g-maleic acid anhydride, SEBS-g-maleic acid anhydride, polyethylene-co-methyl acrylate-co-glycidyl acrylate or polyethylene-co-methyl acrylate-co-glycidyl methacrylate.
Suitable dispersion agents are, for example:
polyacrylates, for example, copolymers having long chain side groups, polyacrylate block copolymers, alkylamides: for example, N,N′-1,2-ethanediylbisoctadecanamide sorbitan esters, for example, monostearyl sorbitan esters, titanates and zirconates, reactive copolymers having functional groups, for example, polypropylene-co-acrylic acid, polypropylene-co-maleic anhydride, polyethylene-co-glycidyl methacrylate, polystyrene-alt-maleic anhydride-polysiloxanes: for example, dimethylsilanediol-ethylene oxide copolymer, polyphenylsiloxane copolymer, amphiphilic copolymers: for example, polyethylene block polyethylene oxide, dendrimers, for example, dendrimers comprising hydroxyl groups.
Suitable antinucleating agents are azine dyes, such as e.g. nigrosine.
Suitable flame retardant agents are, in particular
Suitable plasticizers are, for example, phthalic acid esters, adipic acid esters, esters of citric acid, ester of 1,2-cyclohexane dicarboxylic acid, trimellitic acid esters, isorobide esters, phosphate esters, epoxides such as epoxidized soy bean oil, or aliphatic polyesters.
Suitable mold lubricants and processing aids are, for example, polyethylene waxes, polypropylene waxes, salts of fatty acids such as calcium stearate, zinc stearate, or salts of montane waxes, amide waxes such as erucic acid amide or oleic acid amides, fluoropolymers, silicones, or neoalkoxytitanates and zirconates.
Suitable pigments can be of an inorganic or organic nature. Inorganic pigments are, for example, titanium dioxide, zinc oxide, zinc sulfide, iron oxide, ultramarine, black carbon; organic pigments are, for example, anthraquinones, anthanthrones, benzimidazolones, chinacridones, diketoptyrrolopyrrols, dioxazines, inanthrones, isoindolines, azo compounds, perylenes, phthalocyanines or pyranthrones. Further suitable pigments include effect pigments on a metal base or pearl gloss pigments on a metal oxide base.
Suitable optical brighteners are, for example, bis-beznzoxazoles, phenylcumarines, or bis(styryl)biphenyls and in particular optical brighteners of the formulas:
Suitable filler deactivators are, for example, polysiloxanes, polyacrylates, in particular block copolymers such as polymethacrylic acid polyalkyene oxide or polyglycidyl(meth)acrylates and their copolymers, e.g. with sytrene and epoxides of e.g. the following structures:
Suitable antistatic agents are, for example, ethoxylated alkylamines, fatty acid esters, alkylsulfonates, and polymers such as polyetheramides.
Suitable antiozonants are the above-named amines such as N,N′-di-isopropyl-p-phenylene diamine, N,N′-di-sec-butyl-p-phenylene diamine, N,N′-bis(1,4-dimethylpentyl)-p-phenylene diamine, N,N′-dicyclohexyl-p-phenylene diamine, N-isopropyl-N′-phenyl-p-phenylene diamine, N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylene diamine, N-(1-methylheptyl)-N′-phenyl-p-phenylene diamine, N-cyclohexyl-N′-phenyl-p-phenylene diamine.
Suitable nucleation agents are, talcum, alkali, or alkaline earth salts of mono- and polyfunctional carboxylic acids such as benzoic acid, succinic acid, adipic acid, e.g. sodium benzoate, zinc glycerolate, alumini umhydroxy-bis(4-tert-butyl)benzoate, 2,2′-methylene-bis-(4,6-di-tert-butylphenyl) phosphate, and trisamides and diamides such as trimesic acid tricyclohexylamide, trimesic acid tri(4-methylcyclohexylamide), trimesic acid tri(tert-butylamide), N,N′,N″-1,3,5 benzoltriyltris(2,2-dimethyl-propanamide) or 2,6-naphthalene dicarboxylic acid cyclohexylamide.
Suitable additives for the linear molecular weight structure of polycondensation polymers (chain extenders) are diepoxides, bis-oxazonlines, bis-oxazolones, bis-oxazines, diisoscyanates, dianhydrides, bis-acyllactams, bis-maleimides, dicyanates, carbodiimides.
Further suitable chain extenders are polymer compounds such as e.g. polystyrene polyacrylate polyglycidyl(meth)acrylate copolymers, polystyrene maleic acid anhydride copolymers, and polyethylene maleic acid anhydride copolymers.
Suitable additives for increasing the electrical conductivity are, for example, the antistatic agents mentioned, carbon black and carbon compounds like carbon nanotubes and graphene, metal powder, such as e.g. copper powder, and conductive polymers, such as e.g. polypyrroles, polyanilines and polythiophenes. Suitable additives to increase thermal conductivity are, for example, aluminum nitrides and boron nitrides.
Suitable infrared-active additives are, for example, aluminum silicates or dyestuffs such as phthalocyanines or anthraquinones.
Suitable demolding agents are, for example, silicones, soaps, and waxes, such as montan waxes.
The incorporation of the additives described above and optionally of the additional additives into the plastic takes place by typical processing methods, with the polymers being melted and being mixed with the additive composition in accordance with the invention and the optionally further additives, preferably by mixers, kneaders, or extruders. Extruders such as single-screw extruders, twin screw extruders, planetary gear extruders, ring extruders, and co-kneaders that are preferably equipped with a vacuum degassing are preferred as processing machines. The processing can take place here under air or, optionally, under inert gas conditions.
The additive compositions in accordance with the invention can furthermore be comprised, prepared and incorporated in a polymer in the form of so-called master batches or concentrates that, for example, include 10-90% of the compositions in accordance with the invention.
The present invention moreover relates to a stabilizer composition for the stabilization of halogen-free thermoplastic plastic recyclates, in particular against oxidative, thermal, and/or actinic degradation, consisting of at least one sulfite and/or at least one thiosulfate in combination with at least one primary antioxidant.
Provision is made in a preferred embodiment that the totality of the at least one sulfite and/or thiosulfate and the totality of the at least one primary antioxidant are used in a weight ratio of 1:99 to 99:1, preferably 20:80 to 80:20, further preferably from 30:70 to 70:30, particularly preferably from 40:60 to 60:40.
The additive compositions in accordance with the invention can furthermore be comprised, prepared and incorporated in a polymer in the form of so-called master batches or concentrates that, for example, include 10-90% of the compositions in accordance with the invention.
To this extent, the present invention equally relates to a masterbatch or concentrate comprising 10 to 90 wt % of a stabilizer composition in accordance with one of the two preceding claims and 90 to 10 wt % of a halogen-free thermoplastic or of a plastic recyclate.
The present invention furthermore relates to a plastic composition comprising or consisting of
In accordance with a preferred embodiment, the plastic composition in accordance with the invention has the following composition:
The plastic composition can preferably comprise at least one additive, with the at least one additive preferably being selected from the group consisting of secondary antioxidants, secondary antioxidants excluding phosphite and phosphonites, UV absorbers, light stabilizers, metal deactivators, filler deactivators, antiozonants, nucleation agents, anti-nucleation agents, toughening agents, mold lubricants, rheological modifiers, thixotropic agents, chain extenders, processing aids, demolding aids, flame retardants, pigments, dyes, optical brighteners, antimicrobial active agents, antistatic agents, slip agents, anti-blocking agents, coupling agents, crosslinking agents, anti-cross-linking agents, hydrophilization agents, hydrophobing agents, bonding agents, dispersing agents, compatibilizers, oxygen scavengers, acid scavengers, expanding agents, degradation additives, defoaming agents, odor scavengers, marking agents, anti-fogging agents, fillers, reinforcement materials, and mixtures thereof.
A further embodiment of the plastic composition provides that up to 80 wt %, preferably 0.1 to 60 wt %, particularly preferably 1 to 50 wt %, of at least one plasticizer, filler, reinforcement material, polyol costabilizers, and/or compatibilizers is comprised with respect to 100 wt % of components (A) to (C).
Preferred additives are in particular acid scavengers, light stabilizers or fillers, reinforcement materials, polyol costabilizers, and/or compatibilizers.
In this respect, suitable acid scavengers are selected from the group consisting of salts of monovalent, bivalent, trivalent, or tetravalent metals, preferably alkali metals, alkaline earth metals, aluminum or zinc, in particular formed with fatty acids such as calcium stearate, magnesium stearate, zinc stearate, aluminum stearate, calcium laurate, calcium behenate, calcium lactate, calcium stearoyl-2-lactate. Further classes of suitable acid scavengers are hydrotalcites, in particular synthetic hydrotalcites on the basis of aluminum, magnesium and zinc, hydrocalumites, zeolites, alkaline earth metals, in particular calcium oxide and magnesium oxide and zinc oxide, alkaline earth carbonates, in particular calcium carbonate, magnesium carbonate and dolomite, and hydroxides, in particular brucite (magnesium hydroxide);
The present invention moreover relates to a molding compound or a molded part that can be produced from a plastic composition in accordance with the invention described in the above.
The molding compound or molded part can in particular be in the form of films; packaging, e.g. for foodstuffs or cosmetic products, detergents, cosmetics, or adhesives; hollow bodies, in particular bottles, pouches, screw lid jars, storage and transport containers such as boxes, crates, barrels, buckets, parts of automobiles, railroads, aircraft, ships, and machines such as bumpers, trim, dashboard parts and functional parts, upholstery; construction applications such as sections, construction films, roof sheeting, gable ducts, sidings, noise-insulating walls, drainage gutters, sections such as window and door sections, molded boards, floor coverings, pallets;
The present invention moreover relates to a method of the oxidative, thermal, and/or actinic stabilization of a halogen-free thermoplastic plastic recyclate, in particular against oxidative, thermal, and/or actinic degradation by addition, additiviation, or integration of at least one stabilization composition in accordance with the invention to or into the halogen-free thermoplastic plastic recyclate.
The method in accordance with the invention is in particular characterized in that the thermal stabilization takes place during the thermal processing of the halogen-free thermoplastic plastic recyclate, with the thermal processing in particular taking place under aprotic conditions.
The present invention furthermore relates to the use of the composition in accordance with the invention for the manufacture of
The present invention will be described in more detail with reference to the following example without restricting the invention to the specific parameters.
A post-consumer polypropylene recyclate from accumulator box ground stock (supplier: BSB Braubach) together with the additives given in the Table was conveyed in a circle in the melt at 210° C. in a twin screw microextruder (5 cc, manufacturer DSM) in continuous mode at 200 revolutions a minute for 30 minutes to check the effect of the stabilizer composition in accordance with the invention. The force absorption is measured after 30 minutes. The force is a measure for the toughness of the melt and thus for the molecular weight of the polypropylene recyclate used. The higher the remaining force, the smaller the degradation of the polymer. The respective average of 2 experiments is given.
The synergistic combination in accordance with the invention has proven superior in the present test to the synthetic commercial synergistic combinations of AO-1 and P-1 (Comparison example 3) since there is a smaller degradation of the polymer over the experiment time.
In a further series of experiments, an HDPE recyclate from reusable material collections was extruded five times by means of multiple extrusion on a 16 mm twin screw extruder at 255° C. maximum temperature and 200 revolutions per minute and the respective resulting MVR was determined after the 1st, 3rd, and 5th extrusion.
Post-stabilization of HDPE recyclate
The unstabilized HDPE recyclate shows a clear reduction in the MVR value, i.e. a molecular weight increase as a result of branching and/or interlocking (Comparison example 4).
Standard stabilizers, i.e. AO-1 in combination with P-1 result, as expected, in an improvement, i.e. a smaller reduction of the MVR value; however; no constant value is reached with the used amount. In contrast, Example 4 in accordance with the invention shows an excellent stabilization effect with considerably smaller concentrations up to an MVR value almost unchanged over 5 extrusion steps (Example 4 in accordance with the invention).
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2021 202 103.4 | Mar 2021 | DE | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2022/054870 | 2/25/2022 | WO |
