Flame retarded polymeric composition subtantially free of antimony

Abstract

Technologies described herein provide flame retardant compositions and polymers containing flame retardant compositions that are substantially free of antimony oxide. Examples of the composition include a polymeric composition comprising a polymer, a brominated flame retardant and optionally one or more fillers. The polymeric composition is substantially free of antimony oxide but provide similar or better processing characteristics. The brominated flame may be a brominated anionic styrenic polymer having a number average molecular weight of about 750 to about 20,000 and a bromine content of greater than about 55 wt% or a brominated diphenylalkanes or mixtures of the two.

Description

FLAME RETARDED POLYMERIC COMPOSITIONSUBTANTIALLY FREE OF ANTIMONYCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 686,401 filed August 23, 2024, the entire contents of which are incorporated herein by reference.TECHNICAL FIELD

[0002] This invention relates to flame retarded polymeric compositions that are substantially free of antimony and the uses thereof.BACKGROUND

[0003] Many plastics are flame retarded to avoid ignition and to minimize the spread of fire, including polyolefins. In WO 2005 / 095685, polybrominated anionic styrenic polymers are used to flame retard polyolefins, in conjunction with at least one synergist; the polybrominated anionic styrenic polymer is no more than about 15 wt% of the polyolefin. WO 2001 / 029124 discloses polyolefins with flame retardants, which include the bis(2,3-dibromopropyl ether) of tetrabromobisphenol- A and the bis(2,3-dibromopropyl ether) of tetrabromobisphenol-S. In US 6780348, combinations of a polybromodiphenylalkane and a tetrabromobisphenol- A- bis(bromoalkyl ether) are disclosed. US 8476373 and US 8933159 are directed to brominated anionic chain transfer vinyl aromatic polymers, which can flame retard polyolefins.

[0004] Polymeric compositions comprising halogenated flame-retardants, including brominated flame retardants, are known to those skilled in the art. For example, WO 2017 / 176740 and WO 2017 / 184350 detail the preparation of low molecular weight brominated anionic styrenic polymers. Polymeric compositions only relying on halogenated flame retardants to provide flame retardancy typically require high loadings of flame retardants to meet the most stringent burn performance requirements, such as the UL-94 V-0 vertical burn test. However, high loadings of flame retardants can adversely affect the processability and mechanical performance, such as tensile elongation and impact strength, of the polymeric compositions.AttyDktNo.: 1710.00090WQ

[0005] One method of overcoming processability and mechanical performance issues associated with high halogenated filler concentration is to include a flame -retardant synergist or combinations of flame-retardant synergists. One conventional combination of flameretardant synergists include zinc containing compounds and antimony trioxide and antimony pentoxide (collectively antimony oxide). Antimony trioxide is believed to work by evolution of volatile but dense antimony halide vapors through successive transformation of halogenated antimony oxide complexes generated from reaction between halogenated flame retardant and antimony oxide as the temperature increases. This bonding of the antimony and the halogen creates various vapor phase compounds having a greater effect on the combustion process than the halogenated vapor phase without antimony.

[0006] The use of antimony trioxide as a flame-retardant synergist faces a variety of constraining pressures. For example, antimony trioxide faces regulatory pressure in certain jurisdictions to reduce or abandon its use. Further, sourcing of antimony trioxide may be constrained due to the location of natural deposits and geopolitical tensions. As such, the reduced use of antimony trioxide is desired, however U.S. Patent Application Publication Number 2019 / 0185654 demonstrates that too little antimony trioxide may result in compositions that exhibit unacceptable bum test properties. Further, simply increasing the halogenated filler component may negatively affect mechanical properties of the composition.

[0007] Other attempts at reducing antimony oxide have resulted in the required use of synergists. For example, in US 203 / 00233422, it is shown a flame retardant polymeric composition free of antimony trioxde but requires the use of a zinc synergist. As the US 2023 / 0033422 notes, it provides a polymeric composition that is free of antimony trioxide, enables a coated conductor made of it to pass a VW-i Bum Test and has a Zn:Br molar ratio from greater than 0 to 0.160.

[0008] Considering the benefit of lower toxicity and relative economic benefits, it would be of critical importance if some or all antimony oxide can be replaced while achieving equal or better flame retardant performances.AttyDktNo.: 1710.00090WQSUMMARY OF THE INVENTION

[0009] This invention provides flame retardant compositions and polymers containing flame retardant compositions that are substantially free of antimony oxide. The flame retardants are typically brominated flame retardant such as a brominated anionic styrenic polymer having a number average molecular weight of about 750 to about 20,000 and a bromine content of greater than about 55 wt% or a non-polymeric flame retardant with aromatic bromines or mixtures of the two. Non-limiting examples of non-polymeric flame retardants with aromatic bromines include brominated diphenylalkane and brominated phthalamides.

[0010] An embodiment of this invention is a polymeric composition comprising a polymer; a brominated flame retardant; a filler; wherein the polymeric composition is substantially free of antimony oxide; wherein the brominated flame is a brominated anionic styrenic polymer having a number average molecular weight of about 750 to about 20,000 and a bromine content of greater than about 55 wt% or a brominated diphenylalkanes or mixtures of the two.

[0011] Another embodiment of the invention is the above polymeric composition further comprising an impact modifier and further wherein the impact modifier is selected from ethylene octene copolymers, ethylene hexene copolymers, styrene-ethylene butylene-styrene block copolymer, a maleic anhydride grafted SEBS block copolymer, or a styrene-ethylene propylene- styrene block copolymer or mixtures thereof.

[0012] These and other embodiments and features of this invention will be still further apparent from the ensuing description and appended claims.FURTHER DETAILED DESCRIPTION OF THE INVENTION

[0013] A critical feature of the present invention is that there is provided a polymeric composition comprising a polymer and a flame retardant that is substantially free of antimony oxide. By “substantially free of antimony oxide” it is meant that the concentration of antimony oxide in the composition is well below the acceptable amount used in plastic composites inAttyDktNo.: 1710.00090WQ conjunction with halogenated additives, e.g., not more 1.0% by weight, more preferably, up 0.5% by weight, e.g., 0.0-0.3% by weight (based on the total weight of the composition). Antimony oxide is meant to include all forms of antimony oxide, such as antimony trioxide and antimony pentoxide. Furthermore, it is intended that no antimony oxide is added during the process of making the flame retarded polymeric composition, however, trace amounts as impurities may exist. Most preferably, the compositions of the invention are totally devoid of antimony oxide.

[0014] A brominated flame retardant that can be used in the practice of this invention is a low molecular weight brominated anionic styrenic polymer having a number average molecular weight (Mn) of about 750 or more, preferably about 1000 or more, more preferably about 2000 or more. In some embodiments, these brominated anionic styrenic polymers have an Mnin the range of about 750 to about 20,000, preferably about 1000 to about 7500, and more preferably about 2000 to about 4000.

[0015] Typically, the low molecular weight brominated anionic styrenic polymers contain about 55 wt% or more bromine, preferably about 66 wt% or more bromine, more preferably about 72 wt% or more bromine. In some embodiments, these brominated anionic styrenic polymers contain about 55 wt% to about 77 wt% bromine, preferably about 66 wt% to about 77 wt%, more preferably about 72 wt% to about 76 wt% bromine.

[0016] Preferably, the low molecular weight brominated anionic styrenic polymers are brominated anionic polystyrenes. In some embodiments, the low molecular weight brominated anionic styrenic polymers are brominated anionic polystyrenes having a number average molecular weight of about 750 to about 20,000, and about 55 wt% to about 77 wt% bromine, preferably a number average molecular weight of about 1000 to about 7500, and about 70 wt% to about 77 wt% bromine, more preferably a number average molecular weight of about 2000 to about 4000, and about 72 wt% to about 76 wt% bromine.

[0017] The low molecular weight brominated anionic styrenic polymers can be formed by bromination in an organic solvent. Information on the preparation of low molecular weightAttyDktNo.: 1710.00090WQ brominated anionic styrenic polymers is found for example in International Patent Publications WO 2017 / 176740 and WO 2017 / 184350.

[0018] Another brominated flame retardant that can be used in the practice of this invention is brominated diphenylalkanes, for example e.g., decabromodiphenylethane. Decabromodiphenylethane is produced by methods known in the skill in the art. Among prior processes for production are described in U.S. Pat. Nos. 6,518,468; 6,958,423; 6,603,049; 6,768,033; 6,974,887; and 9,018,298.

[0019] In addition, to the flame retardant optional ingredients can be present. These additional ingredients may include inorganic compounds, impact modifiers, compatibilizers, and other flame retardants, and other thermal stabilizers. Of particular note is the increased amount of inorganic compounds, such as talc or glass fibers, that can be utilized with this invention. This allows for a greater range of formulations as well as more inexpensive formulations.Flame Retardants for Use in the Present Invention

[0020] It has been found that particular flame retardants allow for the elimination of antimony oxide while still maintaining good physical and flame retardant properties. Typically, the brominated flame retardant contains aromatically-bound bromine, and is a) a brominated anionic styrenic polymer having a number average molecular weight of about 750 to about 7500, and / or a bromine content of about 55 wt% to about 77 wt%, and / or b) decabromodiphenylethane.

[0021] A brominated flame retardant that can be used in the practice of this invention is a low molecular weight brominated anionic styrenic polymer having a number average molecular weight (Mn) of about 750 or more, preferably about 1000 or more, more preferably about 2000 or more. In some embodiments, these brominated anionic styrenic polymers have an Mnin the range of about 750 to about 20,000, preferably about 1000 to about 7500, and more preferably about 2000 to about 4000.AttyDktNo.: 1710.00090WQ

[0022] Typically, the low molecular weight brominated anionic styrenic polymers contain about 55 wt% or more bromine, preferably about 66 wt% or more bromine, more preferably about 72 wt% or more bromine. In some embodiments, these brominated anionic styrenic polymers contain about 55 wt% to about 77 wt% bromine, preferably about 66 wt% to about 77 wt%, more preferably about 72 wt% to about 76 wt% bromine.

[0023] Preferably, the low molecular weight brominated anionic styrenic polymers are brominated anionic polystyrenes. In some embodiments, the low molecular weight brominated anionic styrenic polymers are brominated anionic polystyrenes having a number average molecular weight of about 750 to about 20,000, and about 55 wt% to about 77 wt% bromine, preferably a number average molecular weight of about 1000 to about 7500, and about 70 wt% to about 77 wt% bromine, more preferably a number average molecular weight of about 2000 to about 4000, and about 72 wt% to about 76 wt% bromine.

[0024] The low molecular weight brominated anionic styrenic polymers can be formed by bromination in an organic solvent. Information on the preparation of low molecular weight brominated anionic styrenic polymers is found for example in International Patent Publications WO 2017 / 176740 and WO 2017 / 184350.

[0025] Another brominated flame retardant that can be used in the practice of this invention is brominated diphenylalkanes, for example e.g., decabromodiphenylethane. Decabromodiphenylethane is presently sold as a powder derived from the bromination of 1 ,2- diphenylethane. Among prior processes for effecting such bromination are the bromination processes described in U.S. Pat. Nos. 6,518,468; 6,958,423; 6,603,049; 6,768,033; and 6,974,887.

[0026] Mixtures of two or more brominated flame retardants can be used in the practice of this invention. In addition to the brominated anionic styrenic polymers and / or decabromodiphenylethane, the compositions can contain one or more other brominated flame retardants. Suitable brominated flame retardants include hexabromocyclohexane, dibromoethyldibromocyclohexane, monochloropentabromocyclohexane,AttyDktNo.: 1710.00090WQ tetrabromocyclooctane, hexabromocyclododecane, bis(pentabromophenyl)ethane (decabromodiphenyl ethane), hexabromobenzene, dibromo styrene and derivatives thereof, pentabromodiphenyl oxide, octabromodiphenyl oxide (octabromodiphenyl ether), decabromodiphenyl oxide (decabromodiphenyl ether), l,2-bis(tribromophenoxy)ethane, tetradecabromodiphenoxybenzene, 2,4,6-tribromophenol allyl ether, dibromoneopentyl glycol, tribromoneopentyl alcohol, tetrabromobisphenol-A, tetrabromobisphenol A diallyl ether, tetrabromobisphenol-A bis(2,3-dibromopropyl ether), bis(2,4,6-tribromophenoxyethyl) tetrabromobisphenol-A ether, tetrabromobisphenol - bis(2-hydroxyethyl) ether, tetrabromobisphenol-S, tetrabromobisphenol-S bis(2,3-dibromopropyl ether), brominated epoxy oligomer, such as tribromophenol endcapped brominated epoxy oligomers, brominated carbonate oligomers based on tetrabromobisphenol-A such as 2,4,6-tribromophenyl terminated tetrabromobisphenol-A carbonate oligomer and phenoxy-terminated tetrabromobisphenol-A carbonate oligomer, brominated polystyrenes, block copolymers of polystyrene and brominated polybutadiene, poly(dibromophenylene oxide), poly(pentabromobenzyl acrylate), brominated phthalic acids, diallyl tetrabromophthalate, bis(2-ethylhexyl) tetrabromophthalate, tetrabromophthalimide, N,N-ethylene-bis(tetrabromophthalimide), tetrabromophthalic anhydride, a mixed ester of tetrabromophthalic anhydride with diethylene glycol and propylene glycol, N,N'-ethylene-bis-(5,6-dibromonorbornane 2,3-dicarboximide), tris(tribromophenyl)triazine, brominated phenoxytriazines such as tris(tribromophenoxy)triazine, brominated maleimides such as tribromophenyl maleimide, brominated trimethylphenylindan, brominated isocyanurates such as tris(2,3- dibromopropyl)isocyanurate, and tris(tribromoneopentyl) phosphate. Preferred brominated flame retardants to use in admixture with the brominated anionic styrenic polymers include decabromodiphenyl ethane and N,N-ethylene-bis(tetrabromophthalimide)

[0027] In addition, to mixtures of two or more brominated flame retardants, mixtures of nonhalogen flame retardants with the brominated flame retardants can be used in the practice ofAttyDktNo.: 1710.00090WQ this invention. Suitable non-halogen flame retardants include ammonium polyphosphate, piperazine pyrophosphate and the like.The Polymer

[0028] The polymer used in this invention are those typically used and known by those skilled in the ail. Suitable polymers include but are not limited to polycarbonate, polyurethane, polyester, polyamide, polyolefin, styrenic polymer, chlorinated polyethylene, and / or combinations thereof. Suitable polyolefins in the practice of this invention include polyethylenes such as high density polyethylene (HDPE), low density polyethylene (LDPE), and linear low density polyethylene (LLDPE); polypropylene; polybutylenes such as polybutylene terephthalate; copolymers formed from propylene and ethylene, including ethylene propylene diene polymers (EPDM); ethylene and / or propylene copolymers with other olefinic monomers copolymerizable therewith, including polyolefin elastomers and plastomers. Preferred polyolefins include polyethylene, polypropylene, and copolymers formed from propylene and ethylene. Mixtures of polyolefins can be used if desired. Polystyrenes such as high impact polystyrenes may be used. The polymer is typically present in an amount 20 wt% to 70 wt% of the total weight of flame retarded composition.Other Ingredients in the Flame Retarded Polymeric Composition

[0029] Optional ingredients that can be present arc often present in the flame retardant compositions include inorganic compounds, antioxidants, impact modifiers, compatibilizers, halogenated polyethlyenes, pigments, flame retardant synergists, anti-dripping agents, dyes, light stabilizers, UV stabilizers, fillers, antifoaming agents, antimicrobial agents, biocidal agents, buffers, pH stabilizers, fixing agents, anti-static agents, soil repellants, wetting agents, softeners, water repellants, optical brighteners, plasticizers, emulsifiers, acid scavengers, radical scavengers, metal scavengers or deactivators, processing aids, mold release agents, lubricants, anti-blocking agents, antistatic agents, slip additives, blowing agents, antifoggingAttyDktNo.: 1710.00090WQ agents, reinforcing agents, coupling agent, nucleating agents, other flame retardants, and other thermal stabilizers.

[0030] Inorganic compounds are a preferred type of optional ingredient. As used throughout this document, the phrase "inorganic component" refers to one or more inorganic compounds which contain one or more metal atoms that do not have a hydrocarbyl group bound directly to the metal atom(s).

[0031] The inorganic compounds grouped together here are often classified separately, as flame retardant synergists, fillers, pigments, and so forth. Suitable inorganic compounds in the practice of this invention include talc, ammonium phosphate, ammonium polyphosphate (APP) and intumescent systems based on APP, piperazine pyrophosphate and intumescent systems based on piperazine pyrophosphate, ammonium phosphinate, aluminum phosphinate, aluminum diethyl phosphinate, calcium stearate, calcium borate, calcium phosphinate, magnesium hydroxide, magnesium aluminum hydroxide carbonate, zinc borate, zinc oxide, zinc stannate, zinc sulfide, zinc phosphate, zinc phosphinate, zinc diethyl phosphinate, zinc molybdate, tin(IV) oxide, titanium dioxide, titanium phosphate, a-zirconium phosphate, wollastonite, hydrotalcite, silane-modified aluminum silicate, glass fibers, MCA PPM Triazine HF (Poly-[2,4-(piperazine-l,4-yl)-6-(morpholine-4-yl)-l,3,5-triazine] / Piperazine, polymer with morpholine-2,4,6-trichloro-l,3,5-triazine reaction product) and clays including smectites such as montmorillonite, bentonite, nontronite, hectorite, laponite, beidellite, volkonskoite, sauconite, stevensite, and saponite; kaolins such as halloysite; micas such as ledikite; rectorite; tarasovite; kenyaite; permutite; vermiculites; attapulgites; and illites. Mixtures of two or more inorganic compounds can be used if desired, and in some embodiments, more than one inorganic compound is preferred. As is known in the art, some of these inorganic compounds, such as magnesium hydroxide and aluminum hydroxide, can also be helpful in providing additional flame retardancy.

[0032] Preferred inorganic compounds include talc, glass fibers, zinc borate, aluminum phophinate, aluminum diethyl phosphinate, calcium phosphinate, and hydrotalcite.AttyDktNo.: 1710.00090WQ

[0033] A flame retardant additive may include magnesium hydroxide alone or in combination with talc and / or glass fibers. In some ATO-free compositions using PBT as described herein, glass fibers comprised 30 wt% of the composition. In other examples, lower percentages of glass fibers may be used in PBT compositions. For example, 10 to 20 wt% glass fibers may be used. In other examples, 0 to 10 wt% glass fibers may be used in PBT compositions. In some examples with a lower content of glass fibers, a higher percentage of flame retardant may be used, such as 30 to 40 wt%, 30 to 50 wt%, or 40 to 50 wt%.

[0034] In some ATO-free compositions using PP as described herein, fillers are not used. In some examples with no filler or a lower content of filler, a higher percentage of flame retardant may be used, such as 30 to 40 wt%, 30 to 50 wt%, or 40 to 50 wt%.

[0035] Antioxidants that can be used in the practice of this invention include phenolic antioxidants, thioesters, aromatic amines, phosphonites, and phosphite antioxidants. Suitable antioxidants include 2,6-di-tert-butyl-4-methyl phenol, tetrakis(3-(4-hydroxy-3,5-di-tert- butylphenyl)propionyloxymethyl)methane, l,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)-s- triazine-2,4,6(lH,3H,5H)trione, octadecyl 3,5-di-tert-butyl-4-hydroxyhydrocinnamate, 1,3,5- trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, 4,4'-methylenebis(2,6-di-tert- butyl-phenol), ethylenebis(oxyethylene)bis-(3-(5-tert-butyl-4-hydroxy-m-tolyl)-propionate), N,N'-(hexane- 1 ,6-diyl)bis(3-(3,5-di-tert-butyl-4-hydroxyphenyl00propionamide), hexadecyl- 3,5-di-t-butyl-4-hydroxybenzoate, 2,2'-thiodiethylene bis[3-(3,5-di-tert-butyl-4- hydroxyphenyl)propionate], C13-C15 linear and branched alkyl esters of 3-(3'5'-di-t-butyl-4'- hydroxyphenyl)propionic acid, C9-C11 linear and branched alkyl esters of 3-(3',5'-di-t-butyl-4'- hydroxyphenyl)propionic acid, 2,2'-methylenebis(6-tert-butyl-4-methylphenol), 2,2'- ethylidenebis(4,6-di-tert-butylphenol), (l,l-di-tert-butyl)-4- hydroxyphenyl)methyl)ethylphosphonate, N-phenyl-benzenamine reaction products with 2,4,4-trimethylpentene, dimyristyl thiodipropionate, distearyldisulfide, pentaerythritol tetrakis(P-laurylthiopropionate), dioctadecyl 3,3'-thiodipropanoate, didodecyl 3,3'- thiodipropanoate, tris-(2,4-di-tert-butylphenyl)phosphite, bis(2,4-di-tert-AttyDktNo.: 1710.00090WQ butylphcnyljpcntracrythritol diphosphate, (2,4,6-tri-tert-butylphenyl)(2-butyl-2-ethyl-l,3- propanediol) phosphite, tetrakis(2,4-di-tert-butylphenyl)-4,4'-biphenylene diphosphonite, distearylpentaerythritol diphosphite, bis(2,4-dicumylphenyl) pentaerythritol diphosphate, tris(dipropyleneglycol) phosphite, poly(dipropylene glycol) phenyl phosphite, diphenyl isodecyl phosphite, phenyl diisodecyl phosphite, heptakis(dipropyleneglycol) triphosphate, tris(nonylphenyl) phosphite, bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite, 2,2'-ethylidenebis(4,6-di-tert-butylphenyl) fluorophosphonite, 2,2'-methylenebis(4,6-di-tert- butylphenyl)octyl-phosphite, trilauryl trithiophosphite, l,2-bis(3,5-di-tert-butyl-4- hydroxyhydrocinnamoyl)hydrazine, and 1:1:2 combination of calcium (3,5-di-tert-butyl-4- hydroxyphenyl)methyl ethoxyphosphinate, polyethylene wax and tris(2,4-di-tert-butylphenyl) phosphite. Mixtures of two or more antioxidants can be used. Preferred antioxidants include tetrakis(3-(4-hydroxy-3,5-di-tert-butylphenyl)propionyloxymethyl)methane and tris-(2,4-di- tert-butylphenyl) phosphite; more preferred is a combination of tetrakis(3-(4-hydroxy-3,5-di- tert-butylphenyl)propionyloxymethyl)methane and tris-(2,4-di-tert-butylphenyl) phosphite.

[0036] Generally, impact modifiers are rubbers or elastomers. Suitable impact modifiers in the practice of this invention include ethylene octene copolymers and ethylene hexene copolymers. Ethylene octene copolymers or polyolefin elastomers are preferred impact modifiers in the practice of this invention. Mixtures of impact modifiers can be used if desired. In an aspect, the impact modifiers can be a thermoplastic elastomer such as, for example, a styrenic block copolymer, a thermoplastic polyurethane, a nitrile butadiene rubber, an acrylic elastomer, a copolyester elastomer, a thermoplastic polyether ester elastomer (TPEE), a thermoplastic amide ether elastomer (TAEE), a chlorinated rubber, an ionomer, a thermoplastic vulcanizate, or any combination thereof. In one aspect, when the impact modifier is or includes a nitrile butadiene rubber, the nitrile butadiene rubber can be a hydrogenated nitrile butadiene rubber. In another aspect, when the impact modifiers is or includes a styrenic block copolymer, the styrenic block copolymer can be selected from a styrene-ethylene butylene-styrene block copolymer (SEBS), a maleic anhydride grafted SEBS block copolymer, a styrene-ethyleneAttyDktNo.: 1710.00090WQ propylene- styrene block copolymer (SEPS), or any combination thereof. In one aspect, when the impact modifier is or includes SEBS, the SEBS has a styrene to ethylene and butylene ratio of from about 10:90 to about 70:30, from about 20:80 to about 50:50, from about 50:50 to about 70:30, or of about 10:90, 20:80, 30:70, 40:60, 50:50, 60:40, or about 70:30, or a combination of any of the foregoing values, or a range encompassing any of the foregoing values. In another aspect, when the impact modifiers is or includes a thermoplastic polyurethane, the thermoplastic polyurethane can be a polyester polyurethane, a polyether polyurethane, or any combination thereof. In still another aspect, when the impact modifiers is or includes an acrylic elastomer, the acrylic elastomer can be ethylene acrylic terpolymer. In one aspect, when the impact modifiers is or includes a chlorinated rubber, the chlorinated rubber can be polychloroprene, a chloro polyethylene copolymer, or any combination thereof.

[0037] Compatibilizers are sometimes thermoplastic elastomers, maleated copolymers of olefin homopolymers or copolymers, or in .ym / - formed macromolecule catalysts. Compatibilizers suitable for use in the practice of this invention include styrene ethylene butadiene copolymers, especially styrene ethylene / butylene linear triblock copolymers, maleic anhydride modified polypropylene homopolymers, and a sodium ionomer of ethylene / methacrylic acid copolymer. Mixtures of compatibilizers can be used. Preferred compatibilizers include styrene ethylene / butylene linear triblock copolymers.

[0038] Halogenated polyethylenes are polyethylenes containing halogen atoms. Suitable halogenated polyethlyenes include polytetrafluoroethylene and chlorinated polyethylene. Mixtures of halogenated polyethylenes can be used.Flame Retarded Polymer Compositions

[0039] A typical flame retarded polymeric formulation will comprise a polymer and a flame retardant and often a flame retardant synergist. However, a critical feature of the present invention is that the polymeric composition comprising a polymer in and a flame retardant is substantially free of antimony oxide.AttyDktNo.: 1710.00090WQ

[0040] In the flame retarded polymer composition, the flame retardant amount is usually about 15 wt% or more, preferably about 20 wt% or more, more preferably about 24 wt% or more, based on total weight of flame retarded polymer composition. In some embodiments, the flame retardant amount is about 15 wt% to about 45 wt%, preferably about 20 to about 37 wt%, more preferably about 24 to about 35 wt%, based on total weight of flame retarded polymer composition.

[0041] In terms of bromine content, the flame retarded polymer composition preferably contains the brominated flame retardant in an amount to provide about 5 wt% bromine or more, more preferably about 10 wt% bromine or more, even more preferably about 15 wt% bromine or more, based on the total weight of the flame retarded polymer composition. In some embodiments, the brominated flame retardant is in an amount to provide about 5 wt% to about 35 wt% bromine, preferably about 10 wt% to about 25 wt% bromine, more preferably about 15 wt% to about 23 wt% bromine, based on the total weight of the flame retarded polymer composition. When more than one brominated flame retardant is present in the flame retarded polymer composition, these values refer to the combined amount of bromine present in the flame retarded polymer composition.

[0042] One of the benefits that occurs with the removal of antimony oxide, is the ability to utilize less expensive “filler” or “reinforcing” material such as talc or glass fibers. In the present invention, the talc or glass fibers are typically present in the flame retarded polymer composition and in the amount of about 10 wt% or more, preferably about 20 wt% or more, or about 10 wt% to about 50 wt% and preferably about 20 wt% to about 35 wt%, based on the total weight of the polymer composition.

[0043] The total amount of inorganic compounds is in an amount of about 5 wt% or more, preferably about 8 wt% or more, more preferably about 12 wt% or more, based on the total weight of the flame retarded polymer composition. In some embodiments, the total amount of inorganic compounds is typically in an amount of about 5 wt% to about 50 wt%, preferably about 8 wt% to about 35 wt%, more preferably about 12 wt% to about 30 wt%, based on theAttyDktNo.: 1710.00090WQ total weight of the flame retarded polymer composition. When the amount of inorganic compound is less than about 10 wt%, the polymer composition may pass some flammability tests, such as the V-2 standard in the UL-94 vertical bum test, but it is often preferred that the polymer composition meet a more rigorous standard, such as V-0 in the UL-94 vertical burn test, for which a higher amount of brominated flame retardant is usually needed.

[0044] Antioxidants and preferences therefor are as described above. The amount of antioxidant is about 0.05 wt% or more, preferably about 0.1 wt% or more, or about 0.05 wt% to about 1 wt%, preferably about 0.1 wt% to about 0.5 wt%, based on the total weight of the flame retarded polymer composition. When more than one antioxidant is present in the flame retarded polymer composition, these values refer to the combined amount of antioxidants present in the flame retarded polymer composition.

[0045] Impact modifiers and preferences therefor are as described above, and are in an amount of about 0.5 wt% or more, preferably about 2 wt% or more, more preferably about 5 wt% or more, or about 0.5 wt% to about 20 wt%, preferably about 2 wt% to about 15 wt%, more preferably about 5 wt% to about 10 wt%, based on the total weight of the flame retarded polymer composition. When more than one impact modifier is present in the flame retarded polymer composition, these values refer to the combined amount of impact modifiers present in the flame retarded polymer composition.

[0046] Compatibilizers and preferences therefor are as described above and are in an amount of about 0.25 wt% or more, preferably about 1 wt% or more, or about 0.5 wt% to about 20 wt%, preferably about 1 wt% to about 10 wt%, based on the total weight of the flame retarded polymer composition. When more than one compatibilizer is present in the flame retarded polymer composition, these values refer to the combined amount of compatibilizers present in the flame retarded polymer composition.

[0047] The combination of materials, in particular’ talc, and the flame retardants discussed herein, allow the polymeric compositions to meet the rigorous UL-94 V0 testing while maintaining good physical properties. It is typically expected that at high levels of brominatedAttyDktNo.: 1710.00090WQ flame retardant and filler material, such as talc, the polymeric composition will become overly brittle and difficult to extrude due to low flowability. However, it has been found with the flame retardants discussed herein, formulations substantially free of antimony oxide maintain good flowability. In some examples, the flame retardants discussed herein, the compositions maintain good flowability even with higher talc levels.Processes for Forming Flame Retarded Polymer Compositions

[0048] The processes for forming flame retarded polymer compositions of the invention comprise combining at least one brominated flame retardant and at least one polymer. A flame retardant amount of the brominated flame retardant is used. The brominated flame retardant contains aromatically-bound bromine and is a brominated anionic styrenic polymer having a number average molecular weight of about 750 to about 2000, and / or a bromine content of about 55 wt% to about 77 wt%, and / or decabromodiphenylethane.

[0049] When preparing flame retarded polymer compositions of this invention, the individual components of the flame retardant composition of this invention can be blended separately and / or in subcombinations with the substrate or host polymer in appropriate proportions.

[0050] Various known procedures can be used to prepare the flame retarded polymer compositions and masterbatches of this invention. The compounding of the brominated flame retardant, and the other ingredients can be done on compounding equipment such as a single screw extruder, a twin screw extruder, or a Buss kneader. Preferably, the compounding uses an extruder, more preferably a twin-screw extruder. The other ingredients utilized in the practice of this invention can be added in the initial feed port of the extruder or they can be added to the extruder further downstream. When using a twin-screw extruder and glass fibers are a component, it is desirable to add the glass fibers at a downstream portion of the extruder in order to avoid excessive glass fiber breakage. In an extruder, many ingredients typically melt as they are mixed together. The extrudate from the extruder is typically converted into granules or pellets either by cooling strands of the extruding polymer and subdividing theAttyDktNo.: 1710.00090WQ solidified strands into granules or pellets, or by subjecting the extrudate to concurrent die-faced pelletizing and water-cooling or air-cooling. If desired, the compositions of this invention can be formulated as powder or granular blends of the ingredients of the composition.

[0051] The flame retarded polymer compositions of this invention can be used to form articles by molding techniques, including but not limited to injection molding, gas assisted molding, rotomolding, compression molding, blow molding, film insert molding, structural foam molding, extrusion molding, and resin transfer molding. Other techniques that can be used to form articles from the flame retarded polymer in compositions of this invention include thermoforming and extrusion (for example, of sheet, film, or fiber).

[0052] The following examples are presented for purposes of illustration and are not intended to impose limitations on the scope of this invention.EXAMPLES - GENERALEXAMPLES 1-15

[0053] Examples of polypropylene formulations were made to show the effectiveness of ATO free formulations of the current application. The formulations are described below followed by a Table 1 of their performance. Example formulations using varying amounts of ATO were also tested with polypropylene. The ingredients of these examples are listed below: a. PP homopolymer is a polypropylene homopolymer with MFI (230°C / 2.16 kg) = 4 b. PP copolymer is a polypropylene copolymer with MFI (230°C / 2.16 kg) = 12 c. FR1 is a commercial sample of decabromodiphenylethane d. FR2 is a low molecular weight brominated anionic styrenic polymer e. ATO is a commercially available Sb2O3 f. Additive 1 is polyolefin elastomer g. Additive 2 is a SEPS h. Talc is Mistron Vapor RAttyDktNo.: 1710.00090WQ i. MDH is magnesium hydroxide j. PP-g-MAH is maleic anhydride modified polypropylene homopolymerAttyDktNo.: 1710.00090WQTABLE 1AttyDktNo.: 1710.00090WQTABLE 1 (Continued)

[0054] As can be seen in the above table of results, the formulations of the present invention provide UL 94 VO flame retardancy while maintaining good physical characteristics. Each formulation in Ex 1 to Ex 10 and Ex 12 is substantially free of antimony oxide (or includes a minimal amount of ATO), allowing significant flexibility in formulations for any given application. Ex 11 and Ex 13 to Ex 15 are comparative examples that do include varying amounts of ATO. The examples without ATO have similar or improved performance characteristics as the examples with ATO.AttyDktNo.: 1710.00090WQEXAMPLES 16-29

[0055] Examples of polypropylene formulations were made to show the effectiveness of ATO free formulations of the current application. The formulations are described below followed by a Table 2 of their performance. Example formulations using varying amounts of ATO were also tested with polypropylene . The ingredients of these examples are listed below: a. PP is a polypropylene copolymer with MFI (230°C I 2.16 kg) = 12 b. FR1 is a commercial sample of decabromodiphenylethane c. FR2 is a low molecular weight brominated anionic styrenic polymer d. ATO is a commercially available SbsOa e. Additive 1 is polyolefin elastomer f. Additive 2 is a SEPS g. Talc is Mistron Vapor R h. MDH is magnesium hydroxide i. PP-g-MAH is maleic anhydride modified polypropylene homopolymerAttyDktNo.: 1710.00090WQTABLE 2AttyDktNo.: 1710.00090WQTABLE 2 (Continued)

[0056] As can be seen in the above table of results, the formulations of the present invention provide UL 94 VO flame retardancy while maintaining good physical characteristics. Each formulation in Ex 17 to Ex 27 is substantially free of antimony oxide allowing significant flexibility in formulations for any given application. Ex 28 to Ex 29 include minimal amounts of ATO (0.5 wt%).AttyDktNo.: 1710.00090WQEXAMPLES 30-43

[0057] Examples of ABS formulations were made to show the effectiveness of ATO free formulations of the current application. The formulations are described below followed by a Table 3 of their performance. Example formulations using varying amounts of ATO were also tested with ABS The ingredients from this Example are listed below: a. PC is a polycarbonate b. ABS 1 acrylonitrile butadiene styrene c. Additive 3 is a linear block copolymer based on styrene and butadiene d. FR2 is a low molecular weight brominated anionic styrenic polymer e. ATO is a commercially available Sb20a f. Clay g. Zn Borate h. Talc is Mistron Vapor RAttyDktNo.: 1710.00090WQTABLE 3AttyDktNo.: 1710.00090WOTABLE 3 (Continued)

[0058] As can be seen in the above table of results, the formulations of the present invention provide UL 94 VO flame retardancy while maintaining good physical characteristics. Each formulation in Ex 30 to Ex 38 is substantially free of antimony oxide allowing significant flexibility in formulations for any given application. Ex 39 to Ex 43 are comparative examples that do include varying amounts of ATO. The examples without ATO have similar or improved performance characteristics as the examples with ATO. EXAMPLES 44-56

[0059] Examples of high impact polystyrene in formulations were made to show the effectiveness of ATO free formulations of the current application. The formulations a e described below followed by a Table 4 of their performance. Example formulations using varying amounts of ATO were also tested with high impact polystyrene. The ingredients are listed below:AttyDktNo.: 1710.00090WQ a. HIPS is a high impact polystyrene b. Additive 1 is polyolefin elastomer c. FR1 is a commercial sample of decabromodiphenylethane d. FR2 is a low molecular weight brominated anionic styrenic polymer e. ATO is a commercially available 86263 f. Clay g. Zn Borate h. Talc is Mistron Vapor RAttyDktNo.: 1710.00090WQTABLE 4AttyDktNo.: 1710.00090WQTABLE 4 (Continued)

[0060] As can be seen in the above table of results, the formulations of the present invention provide UL 94 VO flame retardancy while maintaining good physical characteristics. Each formulation in Ex 44 to Ex 53 is substantially free (or including a minimal wt%) of antimony oxide allowing significant flexibility in formulations for any given application. Ex 54 to Ex 56 arc comparative examples that do include varying amounts of ATO. The examples without ATO have similar or improved performance characteristics as the examples with ATO. EXAMPLES 57-65

[0061] Examples of polybutylene terephthalate in formulations were made to show the effectiveness of ATO free formulations of the current application. The formulations are described below followed by a Table 5 of their performance. Example formulations using varying amounts of ATO were also tested with polybutylene terephthalate. The ingredients from this Example are listed below:AttyDktNo.: 1710.00090WG a. PBT is a polybutylene terephthalate b. PC is a polycarbonate c. GF1 are glass fibers (10 micron filament diameter) suitable for use in PBT d. GF2 are glass fibers (10 micron filament diameter) suitable for use in PBT e. Additive 4 is an acrylic copolymer f. ATO is a commercially available SbsOa g. FR3 is a brominated polystyrene h. Clay i. Zn Borate j. Talc is Mistron Vapor RAttyDktNo.: 1710.00090WQTABLE 5AttyDktNo.: 1710.00090WQ

[0062] As can be seen in the above table of results, the formulations of the present invention provide UL 94 VO flame retardancy while maintaining good physical characteristics. Each formulation in Ex 57 to Ex 58 is substantially free of antimony oxide allowing significant flexibility in formulations for any given application. Ex 59 to Ex 65 are comparative examples that do include varying amounts of ATO. The examples without ATO have similar or improved performance characteristics as the examples with ATO.

[0063] Components referred to by chemical name or formula anywhere in the specification or claims hereof, whether referred to in the singular or plural, are identified as they exist prior to coming into contact with another substance referred to by chemical name or chemical type (e.g., another component, a solvent, or etc.). It matters not what chemical changes, transformations and / or reactions, if any, take place in the resulting mixture or solution as such changes, transformations, and / or reactions are the natural result of bringing the specified components together under the conditions called for pursuant to this disclosure. Thus, the components are identified as ingredients to be brought together in connection with performing a desired operation or in forming a desired composition. Also, even though the claims hereinafter may refer to substances, components and / or ingredients in the present tense ("comprises", "is", etc.), the reference is to the substance, component or ingredient as it existed at the time just before it was first contacted, blended or mixed with one or more other substances, components and / or ingredients in accordance with the present disclosure. The fact that a substance, component or ingredient may have lost its original identity through a chemical reaction or transformation during the course of contacting, blending or mixing operations, if conducted in accordance with this disclosure and with ordinary skill of a chemist, is thus of no practical concern.

[0064] The invention may comprise, consist, or consist essentially of the materials and / or procedures recited herein.

[0065] As used herein, the term "about" modifying the quantity of an ingredient in the compositions of the invention or employed in the methods of the invention refers to variationAttyDktNo.: 1710.00090WQ in the numerical quantity that can occur, for example, through typical measuring and liquid handling procedures used for making concentrates or use solutions in the real world; through inadvertent error in these procedures; through differences in the manufacture, source, or purity of the ingredients employed to make the compositions or carry out the methods; and the like. The term about also encompasses amounts that differ due to different equilibrium conditions for a composition resulting from a particular initial mixture. Whether or not modified by the term "about", the claims include equivalents to the quantities.

[0066] Except as may be expressly otherwise indicated, the article "a" or "an" if and as used herein is not intended to limit, and should not be construed as limiting, the description or a claim to a single element to which the article refers. Rather, the article "a" or "an" if and as used herein is intended to cover one or more such elements, unless the text expressly indicates otherwise.

[0067] This invention is susceptible to considerable variation in its practice. Therefore the foregoing description is not intended to limit, and should not be constmed as limiting, the invention to the particular exemplifications presented hereinabove.

Claims

THAT WHICH IS CLAIMED IS:

1. A polymeric composition comprising: a polymer; a brominated flame retardant; and optionally a tiller; wherein the polymeric composition is substantially free of antimony oxide; and wherein the brominated flame retardant is a brominated anionic styrenic polymer having a number average molecular weight of about 750 Da to about 20,000 Da and a bromine content of greater than about 55 wt% or a non-polymeric flame retardant with aromatic bromines or mixtures of the two.

2. The polymeric composition of Claim 1 wherein low molecular weight brominated anionic styrenic polymer has a number average molecular weight (Mn) of about 750 Da or more, preferably about 1000 Da or more, more preferably about 2000 Da or more.

3. The polymeric composition of Claim 1 wherein low molecular weight brominated anionic styrenic polymer has a number average molecular weight (Mu) of about 750 to about 20,000 Da, preferably about 1000 Da to about 7500 Da, and more preferably about 2000 Da to about 4000 Da.

4. The polymeric composition of Claim 1 wherein the low molecular weight brominated anionic styrenic polymer about 55 wt% to about 77 wt% bromine, preferably about 66 wt% to about 77 wt%, more preferably about 72 wt% to about 76 wt% bromine.

5. The polymeric composition of Claim 1 wherein a non-polymeric flame retardant with aromatic bromines is a brominated diphenylalkanes, and preferably is decabromodiphenylethane.AttyDktNo.: 1710.00090WQ6. The polymeric composition of Claim 1 wherein a non-polymeric flame retardant with aromatic bromines is a brominated phthalamides, and preferably is ethane bis(tetrabromophthalamide) .

7. The polymeric composition of Claim 1 wherein the flame retardant is about 15 wt% to about 45 wt%, preferably about 20 to about 37 wt%, more preferably about 24 to about 35 wt%, based on total weight of the composition.

8. The polymeric composition of Claim 1 wherein the bromine content is in an amount to provide about 5 wt% to about 35 wt% bromine, preferably about 10 wt% to about 25 wt% bromine, more preferably about 15 wt% to about 23 wt% bromine, based on the total weight of the composition.

9. The polymeric composition of Claim 1, wherein the polymer comprises polycarbonate, polyurethane, polyester, polyamide, polyolefin, styrenic polymer, chlorinated polyethylene, polybutylene, polybutylene terephthalate, and / or combinations thereof.

10. The polymeric composition of Claim 1, wherein the polymer comprises a polyolefin, such as polypropylene homopolymers and copolymers, polyethylene, and polyolefin copolymers such as poly (ethylene- vinyl acetate) (EVA) and poly (ethylene ethyl acrylate) (EEA), polyolefin elastomers and plastomers, as well as derivatives of polyolefins such as chlorinated polyethylene or silane functionalized polyethylene and combinations thereof.

11. The polymeric composition of Claim 9 wherein the polymer comprises polyethylenes such as high density polyethylene (HDPE), low density polyethylene (LDPE), and linear low density polyethylene (LLDPE); polypropylene; copolymers formed from propylene and ethylene, including ethylene propylene diene polymers (EPDM).AttyDktNo.: 1710.00090WQ12. The polymeric composition of Claim 1 wherein the polymer is present in an amount of 20 wt% to 70 wt% of the total weight of the composition.

13. The polymeric composition of Claim 1 wherein the filler is selected from talc, glass fibers, zinc borate, aluminum phosphinate, aluminum diethyl phosphinate, calcium phosphinate, clays, silica, and hydrotalcite and mixtures thereof.

14. The polymeric composition of Claim 13 wherein the filler is one or more of talc and glass fibers.

15. The polymeric composition of Claim 1 wherein the filler is present in the amount of about 10 wt% or more, preferably about 20 wt% or more, or about 10 wt% to about 50 wt% and preferably about 20 wt% to about 35 wt%, based on the total weight of the composition.

16. The polymeric composition of Claim 1 further comprising an impact modifier.

17. The polymeric composition of Claim 16 wherein the impact modifier is selected from ethylene octene copolymers, ethylene hexene copolymers, styrene-ethylene butylenestyrene block copolymer, a maleic anhydride grafted SEBS block copolymer, or a styrene-ethylene propylene- styrene block copolymer or mixtures thereof.

18. The polymeric composition of Claim 17 wherein the impact modifier is a styrene- ethylene butylene- styrene block copolymer (SEBS) or a maleic anhydride grafted SEBS block copolymer or a styrene-ethylene propylene- styrene block copolymer (SEPS).AttyDktNo.: 1710.00090WQ19. The polymeric composition of Claim 18 wherein the SEBS has a styrene to ethylene and butylene ratio of from about 10:90 to about 70:30, from about 20:80 to about 50:50, from about 50:50 to about 70:30, or of about 10:90, 20:80, 30:70, 40:60, 50:50, 60:40, or about 70:30, or a combination of any of the foregoing values.

20. The polymeric composition of Claim 19 wherein the impact modifier in an amount of about 0.5 wt% or more, preferably about 2 wt% or more, more preferably about 5 wt% or more, or about 0.5 wt% to about 20 wt%, preferably about 2 wt% to about 15 wt%, more preferably about 5 wt% to about 10 wt%, based on the total weight of the composition.

21. The polymeric composition of Claim 1 further comprising magnesium hydroxide.

22. The polymeric composition of Claim 1 further comprising a polyolefin elastomer.

23. The polymeric composition of Claim 1 further comprising a maleic anhydride modified polypropylene homopolymer.

24. The polymeric composition of Claim 1 further comprising a linear block copolymer based on styrene and butadiene.

25. The polymeric composition of Claim 1 further comprising a linear block copolymer based on styrene and propylene.

26. The polymeric composition of any one of Claims 1-25 wherein the polymeric composition is not flammable with a rating of V0 based on UL94 standard vertical burn testing.AttyDktNo.: 1710.00090WQ27. A method of making a polymeric composition of any of the claims 1-26 wherein the individual components of the flame retardant composition of this invention can be blended separately and / or in subcombinations with the substrate or host polymer in appropriate proportions.

28. A method of using a polymeric composition of any of the claims 1-26 to form articles by molding techniques, including but not limited to injection molding, gas assisted molding, rotomolding, compression molding, blow molding, film insert molding, structural foam molding, extrusion molding, resin transfer molding, thermoforming and extrusion (for example, of sheet, film, or fiber).

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