Antioxidant blends for emulsion polymerized rubber.

Abstract

The present invention relates to a stabilized composition, particularly one that can be used to stabilize elastomeric materials, such as rubber and / or butadiene-based elastomers. The stabilized composition comprises a first stabilizing component comprising at least one phosphite antioxidant; a second stabilizing component comprising at least one amine antioxidant; and a third stabilizing component comprising at least one phenolic antioxidant. Use of the stabilized composition to stabilize elastomeric materials, stabilized compositions comprising the elastomeric materials and the stabilized composition, and utility products comprising the stabilized composition are also disclosed herein.

Description

[Technical Field]

[0001] This application claims priority to GB Patent Application Publication No. 1907363.4, filed May 24, 2019, the entire contents of which are incorporated herein by reference.

[0002] The present invention relates to a stabilizing composition. More particularly, but not exclusively, the present invention relates to a stabilizing composition useful for stabilizing polymers, particularly elastomers such as rubber and / or butadiene-based elastomers. [Background technology]

[0003] Polymers are used in a wide variety of applications. Elastomers are a type of polymer with a variety of structures, properties, and uses. All exhibit some degree of viscoelasticity and can be made from natural or synthetic polymers. Due to their unique properties, such as high elasticity, durability, and strength, elastomers are used in a wide variety of applications, including tires, tubes, gaskets, and seals. Elastomers are susceptible to physical and visual degradation over time, resulting in poor performance and reduced service life. Factors such as exposure to heat, oxygen, ozone, and radiation (e.g., light) can degrade elastomers, resulting in substantial changes in mechanical properties, for example, as a result of softening or hardening of the elastomer. Thus, the viscosity of rubbers can change substantially with aging. The elastomeric structure degrades, most commonly through chain scission and / or crosslinking. Undesirable odors, discoloration, and fading of elastomers can also be observed as a result of aging. Polybutadiene and its copolymers with fewer active double bonds are primarily susceptible to degradation by chain crosslinking. Elastomers with larger or electron-donating groups, such as natural rubber, polyisoprene, and isobutylene-isoprene rubber, are more susceptible to degradation by chain scission.

[0004] Mooney viscosity values ​​are widely used to estimate an elastomer's ability to flow and retain its shape. To ensure that elastomeric properties are maintained, it is important to ensure that the Mooney viscosity value does not change or fluctuate over time. Therefore, it is important to maintain Mooney viscosity in elastomeric materials to minimize the degradative effects of chain scission and / or crosslinking. Discoloration of elastomers can also be observed as a result of degradation, so minimizing color change is also important. For many elastomer applications, it is desirable for the elastomer to retain certain properties during storage, processing, and subsequent application. More specifically, it is desirable for the elastomer to retain its melt flow, Mooney viscosity, and have excellent color stability during storage and even during prolonged or repeated exposure to temperature fluctuations during storage. Mooney viscosity (M L It is known to add different types of additives to elastomers, in particular antioxidants, to help preserve elastomeric properties such as thermal expansion (temperature at 100°C) and color stability (as measured by the yellowness index).

[0005] U.S. Pat. No. 9,309,379 describes a composition comprising emulsion crude rubber, synthetic latex, or natural rubber latex, which is susceptible to degradation, and a stabilizer comprising a mixture selected from a specific group of alkylthiomethylphenol-type compounds and styrenated diphenylamines. U.S. Pat. No. 4,489,099 describes a chewing gum composition (gum base) that utilizes a combination of dilauryl thiodipropionate and at least one member selected from the group consisting of t-butyl-hydroquinone (TBHQ) and vitamin E as an antioxidant stabilizer system. EP 2980146 describes an elastomer compositing comprising a diene-based elastomer containing an antioxidant, the antioxidant comprising a combination of tris(nonylphenyl)phosphite (TNPP) and tetramethylethylenediamine (TMEDA) in a mass ratio of TNPP to TMEDA ranging from 4 / 1 to 50 / 1. Also disclosed are rubber compositions containing such elastomer compositings, articles of manufacture such as tires containing such elastomer compositings or rubber compositions, and methods of manufacture. European Patent No. 2159264 describes an acrylic rubber composition and vulcanized rubber, which ensures the heat resistance of the vulcanized rubber and minimizes changes in the elongation at break (EB) and hardness of the vulcanized rubber, particularly under heated conditions. The acrylic rubber composition contains a carboxyl group-containing acrylic rubber, 10 to 100 parts by mass of carbon black, 0.1 to 15 parts by mass of at least one primary antioxidant selected from the group consisting of amine antioxidants and phenolic antioxidants, and 0.1 to 15 parts by mass of at least one secondary antioxidant selected from the group consisting of phosphorus antioxidants and sulfur antioxidants, per 100 parts by mass of the carboxyl group-containing acrylic rubber. WO 2015 / 114131 discusses compositions useful for stabilizing organic polymers, particularly natural or synthetic rubbers, against oxidative degradation and damage, comprising a) poly(dichloropentadiene-co-p-cresol) (Formula I); b) a sterically hindered phenol of Formula II; and c) an alkylthiophenol of Formula III. [ka]

[0006] WO 2018 / 041649 describes a liquid antioxidant composition for use in raw rubber, comprising: a) 5 to 30% by weight of at least one aromatic amine antioxidant; b) 20 to 70% by weight of at least one hindered phenol antioxidant; c) 0 to 40% by weight of at least one phosphite antioxidant; and d) 20 to 40% by weight of at least one solvent having a boiling point greater than 185°C and a freezing point less than -10°C at 101.325 kPa. The weight percent of components a), b), c), or d) is based on the total weight of the antioxidant composition, and the mixture of components a), b), and c) is liquid at 25°C and 101.325 kPa. WO 2007 / 050991 describes a composition comprising an antioxidant; and at least one additive selected from the group consisting of phosphorus stabilizers, acid stabilizers and co-stabilizers. GB 2322374 describes a composition comprising an organic material susceptible to oxidative, thermal or light-induced degradation; at least one compound of the benzofuran-2-one type; at least one compound from the group of organic phosphites or phosphonites; at least one compound from the group of phenolic antioxidants; and at least one compound from the group of sterically hindered amines. JP 2018-070747 A describes a polyolefin resin material stabilized with a phenolic antioxidant, a phosphorus-based antioxidant, and a hindered amine light stabilizer. JP 2003-012900 A describes a composition containing an aromatic amine-based antioxidant, a hindered phenolic antioxidant, a sulfur-based antioxidant, and a phosphorus-based antioxidant. U.S. Patent Application Publication No. 2007 / 0254990 describes a pipe coating resin composition having an oxidation induction time of greater than 5 minutes, the composition comprising a thermoplastic ethylene-alphaolefin copolymer composition having a melt index of 1 to 10 grams / 10 minutes as measured by ASTM D1238 and a molecular weight distribution of 2.0 to 3.0; and an antioxidant system including 250 to 2500 ppm of a hindered phenol antioxidant, a secondary antioxidant that is a phosphorus(III) compound, and a hindered amine light stabilizer. Summary of the Invention

[0007] There is a continuing need in the industry for improved stabilized compositions, particularly those that do not discolor, Mooney viscosity change, and have undesirable odors when exposed to temperature fluctuations during extended storage or repeated storage. DETAILED DESCRIPTION OF THE INVENTION

[0008] According to a first aspect of the present invention, there is provided a stabilizing composition for elastomers, comprising: a. a first stabilizing component comprising at least one phosphite antioxidant; b. a second stabilizing component comprising at least one amine antioxidant; and c. a third stabilizing component comprising at least one phenolic antioxidant. Surprisingly, the inventors have found that the stabilizing compositions according to the present invention are highly effective in stabilizing articles made with elastomers, particularly butadiene-based elastomers, with superior property retention compared to compositions previously used in the art. The elastomer may be butadiene-based. In this context, "butadiene-based" means that the elastomer contains, as a monomeric base unit, butadiene or a butadiene derivative, such as chloroprene. For example, the elastomer may include polybutadiene (BR), nitrile rubber (NBR), styrene-butadiene (SBR), polychloroprene (CR), and / or compatible mixtures of two or more thereof. Surprisingly, it has been found that elastomeric materials incorporating the stabilizing compositions of the present invention outperform the same elastomeric materials stabilized with the industry standard 4,6-bis(octylthiomethyl)-o-cresol (Lowinox® 520, CAS 110553-27-0) in terms of Mooney viscosity retention, color performance, and have an overall lower odor. Thus, the stabilizing compositions of the present invention can be used to replace conventional additives.

[0009] Without being bound by theory, it is believed that the antioxidants of the present invention exhibit a synergistic effect on stabilized compositions or articles, such as elastomeric materials and articles of manufacture thereof. This synergistic blend significantly improves Mooney viscosity retention and color retention during heat aging, and is important for lower initial color. The stabilizing composition of the present invention, when added to an elastomer, can cause the elastomer to exhibit a lesser change in Mooney viscosity (measured in accordance with ASTM D1646) over a heat aging period of 6 days at 100°C than the same elastomer to which an equivalent w / w amount of the same stabilizing composition without any amine component has been added. This accelerated thermal aging test uses high temperatures (100°C) to simulate several months of varying storage and shipping conditions. It is a widely accepted standard quality control test for elastomers. This accelerated thermal aging test is used to predict the long-term thermal and storage stability of elastomers. The maximum % variation (measured as the % difference between the starting Mooney viscosity and the highest and / or lowest Mooney viscosity measured) can be such that the viscosity of the elastomer (measured according to ASTM D1646) varies by less than 30%, less than 25%, less than 20%, less than 16%, or less than 10% over a 6 day period. The stabilizing compositions of the present invention, when added to elastomers, can provide the elastomers with an Initial Yellowness Index value (0 days) of less than about 15, less than about 10, or less than about 8 (measured according to ASTM E313). The stabilizing compositions of the present invention, when added to elastomers, can provide elastomers with Yellowness Index values ​​(measured according to ASTM E313) of less than 45, less than 40, less than 37, less than 35, or less than 30 after 4 days.

[0010] In the following paragraphs, compounds designated by the trade names Aminox®, Anox®, BLE®, DURAZONE®, FLEXZONE®, Rowinox®, NAUGALUBE®, Naugard®, NAUGAWHITE®, NOVAZONE®, OCTAMINE®, and WESTON® are available from SI Group USA (USAA), LLC, 4 Mountain View Terrace, Suite 200, Danbury, CT 06810. The phosphite antioxidant may be a liquid at ambient conditions. The amine antioxidant may be a liquid at ambient conditions. Preferably, both the phosphite antioxidant and the amine antioxidant are liquid at ambient conditions. However, in some instances, a stabilized composition according to the present invention that is liquid at ambient conditions can be made by blending a liquid phosphite antioxidant with a solid amine antioxidant. It may also be possible to make stabilized compositions according to the present invention that are liquid at ambient conditions by blending a solid phosphite antioxidant with a liquid amine antioxidant. By "ambient conditions" we preferably mean a temperature of 50° C. or less, more preferably a temperature of 30° C. or less, and most preferably a temperature of 25° C. or less, and atmospheric pressure, i.e., 101.325 kPa. For example, "ambient conditions" can mean a temperature of 25° C. and atmospheric pressure. Preferably, the stabilized composition is a liquid at ambient conditions.

[0011] The phosphite antioxidants provided in the stabilized compositions of the present invention are selected so that the stabilized compositions are liquid at ambient conditions, as described above. This is often accomplished by selecting a separate phosphite antioxidant component that is itself a liquid at ambient conditions. The phosphite antioxidant may include an organic phosphite antioxidant. The phosphite antioxidant may include a triaryl phosphite, a trialkyl phosphite, and / or an alkylaryl phosphite. The phosphite antioxidant may include a triaryl phosphite, optionally triphenyl phosphite. The phosphite antioxidant may include one or more triaryl phosphites of formula I: [ka] wherein R1, R2, and R3 are independently selected from alkylated aryl groups of Formula II: [ka] wherein R4, R5, and R6 are independently selected from hydrogen and C1-C 20 alkyl, with the proviso that at least one of R4, R5, and R6 is not hydrogen. R4, R5 and R6 are independently hydrogen and C1-C 10 alkyl, provided that at least one of R4, R5, and R6 is not hydrogen. R4, R5, and R6 may be independently selected from the group consisting of hydrogen and C1-C6 alkyl, provided that at least one of R4, R5, and R6 is not hydrogen. C1-C6 alkyl may be selected from methyl, ethyl, propyl, butyl, pentyl, hexyl and / or their isomers such as isopropyl, isobutyl, sec-butyl, tert-butyl, isopentyl, tert-pentyl and / or neopentyl. At least one of R4, R5 and R6 may be selected from the group consisting of tert-butyl and / or tert-pentyl.

[0012] The one or more triaryl phosphites may have the structure of formula (III): [ka] wherein R7, R8, and R9 are independently selected from methyl and ethyl groups; and n is 0, 1, 2, or 3. The one or more triaryl phosphites may be independently selected from the group consisting of tris(4-tert-butylphenyl)phosphite; tris(2,4-di-tert-butylphenyl)phosphite; bis(4-tert-butylphenyl)-2,4-di-tert-butylphenyl phosphite; bis(2,4-di-tert-butylphenyl)-4-tert-butylphenyl phosphite; tris(4-tert-pentylphenyl)phosphite; tris(2,4-di-tert-pentylphenyl)phosphite; bis(4-tert-pentylphenyl)-2,4-di-tert-pentylphenyl phosphite; bis(2,4-di-tert-pentylphenyl)-4-tert-pentylphenyl phosphite; and / or blends thereof. The one or more triaryl phosphites may be independently selected from the group consisting of tris(4-tert-pentylphenyl)phosphite; tris(2,4-di-tert-pentylphenyl)phosphite; bis(4-tert-pentylphenyl)-2,4-di-tert-pentylphenyl phosphite; bis(2,4-di-tert-pentylphenyl)-4-tert-pentylphenyl phosphite; and / or blends thereof. The phosphite antioxidant may comprise a blend of triaryl phosphites as described above. Preferably, the phosphite antioxidant comprises a blend of at least two different triaryl phosphites, at least three different triaryl phosphites, or at least four different triaryl phosphites.

[0013] Particularly preferred phosphite antioxidants according to the present invention include mixed 2,4-bis(1,1-dimethylpropyl)phenyl and 4-(1,1-dimethylpropyl)phenyl phosphite (WESTON® 705, CAS 939402-02-5). The present inventors have discovered that certain advantages are realized when the phosphite antioxidant contains one or more triaryl phosphites. In particular, it has been found that, compared to other known phosphite antioxidants, particularly alkylaryl phosphites such as tetra C12-15 alkyl(propane-2,2-diylbis(4,1-phenylene))bis(phosphite) (CAS 96152-48-6), triaryl phosphites are much more stable and less susceptible to hydrolysis when combined with elastomers under elastomer processing conditions. In WO 2018 / 041649, a key component of the antioxidant composition is a solvent, which is used to ensure that the antioxidants, particularly the phosphite antioxidants, do not hydrolyze during the production of raw rubber. In contrast, the stabilized compositions of the present invention are stable under elastomer processing conditions and can therefore be prepared without any solvent.

[0014] The phosphite antioxidant may be a nonylphenyl-free antioxidant. The phosphite antioxidant may include a trialkyl phosphite, such as DOVERPHOS® LGP-11 (available from Dover Chemicals). The phosphite antioxidant may include an alkylaryl phosphite, such as tris(tridecyl) phosphite (WESTON® TTDP, CAS 25488-25-3). Specific, non-limiting examples of phosphite antioxidants include, for example, 2,4-bis(1,1-dimethylpropyl)phenyl and 4-(1,1-dimethylpropyl)phenyl mixed phosphite (WESTON® 705 (CAS 939402-02-5); tris(nonylphenyl)phosphite (WESTON® TNPP, CAS 26523-78-4); tris(tridecyl)phosphite (WESTON® TTDP, CAS 25488-25-3); trilauryl phosphite (WESTON® TLP, CAS 3 076-63-9; triisodecyl phosphite (WESTON® TDP, CAS 25448-25-3); phenyl diisodecyl phosphite (WESTON® PDDP, CAS 25550-98-5); diphenyl isodecyl phosphite (WESTON® DPDP, CAS 26544-23-0); triisooctyl phosphite (TOP, CAS 25103-12-52); tris(2-ethylhexyl) phosphite (CAS 78-42-2); 2-ethylhexyl phenyl phosphite mixed esters (mixed 2-ethylhexyl phenyl phosphite ester) (WESTON® EHDP, CAS 15647-8-2); tris(dipropylene glycol) phosphite (WESTON® 430, CAS 36788-39-3); poly 4,4'-isopropylidenediphenol C12-15 alcohol phosphite (WESTON® 439, CAS 96152-48-6); polymeric liquid phosphite (DOVERPHOS® LGP-11, available from Dover Chemicals); 4,4'-butylidenebis(3-methyl-6-tert-butylphenyl)alkyl(C13) phosphite; and / or compatible mixtures of two or more thereof. The phosphite antioxidant may include 2,4-bis(1,1-dimethylpropyl)phenyl and 4-(1,1-dimethylpropyl)phenyl mixed phosphite (WESTON® 705, CAS 939402-02-5) and / or tris(tridecyl) phosphite (WESTON® TTDP, CAS 25488-25-3). The phosphite antioxidant may include 2,4-bis(1,1-dimethylpropyl)phenyl and 4-(1,1-dimethylpropyl)phenyl mixed phosphite (WESTON® 705, CAS 939402-02-5).

[0015] The phosphite antioxidant may be present in an amount of about 20 to about 95% by weight of the stabilized composition, about 25 to about 90% by weight of the stabilized composition, about 30 to about 85% by weight of the stabilized composition, about 35 to about 70% by weight of the stabilized composition, or about 50 to about 65% by weight of the stabilized composition. The phosphite antioxidant is preferably present in an amount greater than about 40% by weight of the stabilized composition. For example, the phosphite antioxidant may be present in an amount from greater than 40% by weight to about 60, about 65, about 70, about 75, about 80, about 85, about 90, or about 95% by weight of the stabilized composition. The phosphite antioxidant may be present in an amount from about 41, about 42, about 45, or about 50% by weight of the stabilized composition to about 60, about 65, about 70, about 75, about 80, about 85, about 90, or about 95% by weight of the stabilized composition. For example, the phosphite may be present in an amount from about 42 to about 75% by weight of the stabilized composition, from about 45 to about 70% by weight of the stabilized composition, or from about 50 to about 65% by weight of the stabilized composition. The phosphite antioxidant may be a liquid at a temperature of not more than 50° C., optionally not more than 30° C., optionally not more than 25° C., and at atmospheric pressure, i.e., 101.325 kPa. The phosphite antioxidant may be a liquid at a temperature of 25° C., and at atmospheric pressure, i.e., 101.325 kPa.

[0016] The stabilizing component (b) comprises one or more amine antioxidants. Specific, non-limiting examples of amine antioxidants include, for example, 4,4'-bis(α,α-dimethylbenzyl)diphenylamine (Naugard® 445, CAS 10081-67-1); butylated octylated mixed diphenylamine (Naugard® PS30, CAS 68411-46-1); octylated diphenylamine (Octamine®, CAS 101-67-7); nonylated diphenylamine (NAUGALUBE® 438L, CAS 122-39-4); polymerized 1,2-dihydro-2,2,4-trimethylquinoline (Naugard® Q, CAS 26 780-96-1; N,N-bis-(1,4-dimethylpentyl)-p-phenylenediamine (FLEXZONE® 4L, CAS 3081-14-9); acetone diphenylamine (Aminox®, CAS 68412-48-6); reaction products of diphenylamine with acetone (BLE®, CAS 112-39-4); mixed N,N'-phenyl and tolyl derivatives of 1,4-benzenediamine (NOVAZONE® AS, CAS 68953-84-4); benzamine, N-phenyl-, reaction products with 2,4,4-trimethylpentene (benzamine, N-phenyl-, reaction products with 2,4,4-trimethylpentene) (Irganox® 5057, CAS 68411-46-1, available from BASF); N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (Santoflex® 6PPD, CAS 793-24-8, available from Eastman); N,N'-diphenyl-p-phenylenediamine (DPPD, CAS 74-31-7); N-isopropyl-N '-Phenyl-1,4-phenylenediamine (IPPD, CAS 101-72-4); 2,4,6-tris-(N-1,4-dimethylpentyl-p-phenylenediamino)-1,3,5-triazine (DURAZONE® 37, CAS 121246-28-4); N,N'-bis(1,4-dimethylpentyl)-p-phenylenediamine (Santoflex® 77PD, CAS 3081-14-9, available from Eastman);and / or may comprise a compatible mixture of two or more thereof; Amine antioxidants may include 4,4'-bis(α,α-dimethylbenzyl)diphenylamine (Naugard® 445, CAS 10081-67-1) and / or butylated octylated mixed diphenylamines (Naugard® PS30, CAS 68411-46-1). Amine antioxidants may include butylated octylated mixed diphenylamines (Naugard® PS30, CAS 68411-46-1). Butylated octylated mixed diphenylamine (Naugard® PS30, CAS 68411-46-1) is a liquid amine antioxidant that particularly facilitates the preparation of liquid blends according to the present invention. The amine antioxidant may be present in an amount of from about 1 to about 40% by weight of the stabilized composition, from about 1 to about 30% by weight of the stabilized composition, from about 5 to about 25% by weight of the stabilized composition, or from about 7 to about 20% by weight of the stabilized composition.

[0017] The amine antioxidant may be a secondary amine. The amine antioxidant may be an aromatic amine. Amine antioxidants may have the general formula -R-NH-R', where optionally the R and / or R' groups are aromatic. R and R' may be the same or different. Amine antioxidants may have the general formula R-NH-R'-NH-R, where optionally R' is aromatic and / or the R groups are aromatic and / or alkyl. R and R' may be the same or different. The amine antioxidant may contain at least one aromatic group, or at least two aromatic groups. The amine antioxidant may comprise a single compound or a blend of two or more compounds. The amine antioxidant may have a total nitrogen content of at least 3.5 w / w% or at least 4 w / w%.

[0018] The stabilizing component (c) comprises one or more phenolic antioxidants. The phenolic antioxidant may comprise a single compound or a blend of two or more compounds. The phenolic antioxidant may be optionally substituted. The phenolic antioxidant may include semi-hindered and / or hindered phenolic antioxidants. The phenolic antioxidant may include a hindered phenolic antioxidant. By "hindered" herein, we preferably mean that the phenolic antioxidant contains substituted hydrocarbyl groups in both ortho positions relative to the phenolic -OH group with respect to the aromatic ring, and each of these substituents is branched at the C1 and / or C2 positions, preferably the C1 position. By "semi-hindered" herein, we preferably mean that the phenolic antioxidant comprises at least one substituted hydrocarbyl group in the ortho position relative to the phenolic -OH group with respect to the aromatic ring, with the or each substituent being branched at the C1 and / or C2 position, preferably the C1 position.

[0019] The phenolic antioxidant may comprise a substituted phenolic group, preferably two substituted phenolic groups, in this case preferably ortho to the phenolic -OH group. The or each substituent on the phenol group may comprise an alkyl group, optionally a branched chain alkyl group, optionally t-butyl. The phenolic antioxidants may be further substituted at the meta and para positions relative to the phenolic -OH group. The phenolic antioxidant may contain multiple phenolic groups. Specific, non-limiting examples of phenolic antioxidants include C13-C15 linear and branched alkyl esters of 3-(3',5'-di-t-butyl-4-hydroxyphenyl)propionate (Anox® 1315, CAS 171090-93-0); octadecyl 3-(3',5'-di-t-butyl-4-hydroxyphenyl)propionate (Anox® PP18, CAS 2082-79-3); isooctyl 3-(3',5'-di-t-butyl-4-hydroxyphenyl)propionate (Anox® PP18, CAS 2082-79-3); ) propionate (Naugard® PS48, CAS 125643-61-0); methyl 3-(3',5'-di-tert-butyl-4-hydroxyphenyl)propionate (CAS 6386-38-5); pentaerythritol tetrakis(3-(3,5-di-tert.butyl-4-hydroxyphenyl)propionate (Anox® 20, CAS 6683-19-8); butylated hydroxytoluene (BHT, CAS 128-37-0); butylated hydroxyethylbenzene (B HEB, CAS 4130-42-1; butylated octylated phenol (Annox® T, CAS 12674-05-4); styrenated phenol (Naugard® SP, CAS 61788-44-1); styrenated p-cresol (Naugard® 431, CAS 1817-68-1); benzenepropanoic acid, 3,5-bis(1,1-dimethylethyl)-4-hydroxy-C7-C9 side chain alkyl ester (Irganox® 1135, CAS 125643- 61-0 (available from BASF); 2,2-methylenebis(6-nonyl-p-cresol) (NAUGAWHITE®, CAS 7786-17-6); 4-sec-butyl-2,6-di-tert-butylphenol (CAS 17540-75-9); 2-tert-butyl-4,6-dimethylphenol (Rowinox® 624, CAS 1879-09-0); mixed tert-butylated phenols (Isonox® 133, CAS 60083-44-5 (SI Group Inc.), 2750 Balltown Road, Schenectady, NY 12301, USA); 4,4'-methylenebis(2,6-di-tert-butylphenol) (CAS 118-82-1); methyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (PP base, CAS 6386-38-5); 2,4-dimethyl-6-(1-methylpentadecyl)-phenol (CAS 134701-20-5); and / or compatible mixtures of two or more thereof. Phenolic antioxidants may include 3-(3',5'-di-t-butyl-4-hydroxyphenyl)propionate (Anox® 1315, CAS 171090-93-0) and / or C13-C15 linear and branched alkyl esters of isooctyl 3-(3',5'-di-t-butyl-4-hydroxyphenyl)propionate (Naugard® PS48, CAS 125643-61-0).

[0020] The phenolic antioxidant may be present in an amount of about 5 to about 70% by weight of the stabilized composition, about 10 to about 60% by weight of the stabilized composition, about 15 to about 55% by weight of the stabilized composition, about 20 to about 50% by weight of the stabilized composition, or about 20 to about 40% by weight of the stabilized composition. The phenolic antioxidant may be selected to be liquid at a temperature of not more than 50° C., optionally not more than 30° C., optionally not more than 25° C., and at atmospheric pressure, i.e., 101.325 kPa. The phenolic antioxidant may be liquid at a temperature of 25° C. and at atmospheric pressure, i.e., 101.325 kPa. The ratio of phosphite antioxidant to amine antioxidant to phenolic antioxidant in the stabilized composition can be (about 35 to about 70):(about 1 to about 30):(about 15 to about 35); (about 45 to about 65):(about 5 to about 25):(about 15 to about 30); or (about 50 to about 65):(about 7 to about 20):(about 20 to about 30). Additional antioxidants, such as hydroxylamines or precursors thereof, lactone radical scavengers, acrylate radical scavengers, UV absorbers and / or chelating agents may be included in the stabilized composition. The stabilizing compositions according to the present invention are particularly effective in stabilizing elastomeric materials, for example, against oxidation, heat and / or radiation (e.g., light) induced degradation.

[0021] The stabilized composition according to the present invention may further comprise a fourth stabilizing component comprising at least one sulfur-containing antioxidant. For example, the stabilizing composition may comprise: a. a first stabilizing component comprising at least one phosphite antioxidant; b. a second stabilizing component comprising at least one amine antioxidant; c. a third stabilizing component comprising at least one phenolic antioxidant; and optionally, d. a fourth stabilizing component comprising at least one sulfur-containing antioxidant. The sulfur-containing antioxidant may contain one or more thioether groups. The sulfur-containing antioxidant may contain one or more thioester groups. The sulfur-containing antioxidant may include a sulfur-containing phenolic antioxidant. The sulfur-containing antioxidant may be a liquid at ambient conditions. Specific, non-limiting examples of sulfur-containing antioxidants include 4,6-bis(octylthiomethyl)-o-cresol (Lowinox® 520, CAS 110553-27-0); 2,2'-thiodiethylenebis[3(3,5-di-t-butyl-4-hydroxyphenyl)propionate] (Anox® 70, CAS 41484-35-9); dilauryl thiodipropionate (Naugard® DLTDP, CAS 123-28-4); distearyl thiodipropionate (Naugard® ) DSTSP, CAS 693-36-7); ditridecylthiodipropionate (Naugard® DTDTDP, CAS 10595-72-9); pentaerythritol tetrakis(β-laurylthiopropionate) (Naugard® 412S, CAS 29598-76-3); 2,4-bis(dodecylthiomethyl)-6-methylphenol (Irganox® 1726, CAS 110675-26-8 (available from BASF)); and / or compatible mixtures of two or more thereof. Sulfur-containing antioxidants may include 4,6-bis(octylthiomethyl)-o-cresol (Rowinox® 520, CAS 110553-27-0) and / or ditridecylthiodipropionate (Naugard® DTDTDP, CAS 10595-72-9).

[0022] The sulfur-containing antioxidant may be present in an amount of about 0 to about 50% by weight of the stabilized composition, about 1 to about 40% by weight of the stabilized composition, about 2 to about 30% by weight of the stabilized composition, about 2 to about 20% by weight of the stabilized composition, or about 2 to about 10% by weight of the stabilized composition. The ratio of phosphite antioxidant to amine antioxidant, phenolic antioxidant, and sulfur-containing antioxidant in the stabilized composition is: (about 35 to about 70):(about 1 to about 30):(about 15 to about 35):(about 0 to about 20); (about 45 to about 65): (about 5 to about 25): (about 15 to about 30): (about 1 to about 15); or It may be (about 50 to about 65):(about 7 to about 20):(about 20 to about 30):(about 1 to about 5).

[0023] According to a second aspect of the present invention, there is provided the use of a stabilising composition for stabilising an elastomeric material. Elastomers are amorphous polymers with a glass transition temperature below ambient temperature, preferably below the temperature of use. Due to their low glass transition temperature, elastomers have excellent viscoelastic properties such as high elasticity, high impact resistance, etc. The elastomers can be thermoplastic or thermoset, vulcanized or unvulcanized. The elastomeric material may include natural rubber, synthetic rubber, and / or blends of elastomers and plastics such as high impact polystyrene (HIPS) or acrylonitrile butadiene styrene (ABS). The elastomer may be butadiene-based. As outlined above, in this context, "butadiene-based" means that the elastomer contains, as a monomeric base unit, butadiene or a butadiene derivative, such as chloroprene. For example, the elastomer may include polybutadiene (BR), nitrile rubber (NBR), styrene-butadiene (SBR), polychloroprene (CR), and / or compatible mixtures of two or more thereof.

[0024] According to a third aspect of the present invention, a. Elastomer material b. Stabilized Compositions According to the Present Invention The present invention provides a stabilized elastomeric composition comprising: The stabilized elastomeric composition may be suitable for stabilizing elastomeric materials such as rubber. The rubber may include natural rubber, synthetic rubber, and / or combinations thereof. The elastomeric material may be the product of emulsion or solution polymerization. The elastomeric material may or may not be crosslinked after incorporating the above stabilization treatment into the end use application. The stabilized elastomeric composition may further comprise any material suitable for combining with the elastomeric material and the stabilized composition of the present invention. As specific, non-limiting examples, the elastomer may include natural polyisoprene (cis-1,4-polyisoprene, natural rubber (NR)); gutta-percha (trans-1,4-polyisoprene); synthetic polyisoprene; polybutadiene (butadiene rubber (BR)); polychloroprene (CR); butyl rubber (copolymer of isobutylene and isoprene, IIR); halogenated butyl rubber; styrene-butadiene (copolymer of styrene and butadiene, SBR), nitrile rubber (buna-N rubber (NBR)); hydrogenated nitrile rubber (HNBR), and / or compatible mixtures of two or more thereof. The elastomer may be emulsion polymerized including at least one of styrene butadiene (SBR); nitrile rubber (NBR); polybutadiene (BR); polychloroprene (CR). The elastomer may contain butadiene as one of the building blocks. Other suitable building block comonomers may be styrene, acrylonitrile, ethylene or propylene. The elastomers may use different catalyst systems, including metallocenes.

[0025] The present invention also relates to useful articles comprising the stabilized elastomeric compositions described herein. The stabilizing composition according to the present invention may be added to the elastomeric material in an amount of about 0.01 to about 5 w / w%, about 0.05 to 3 w / w%, about 0.1 to about 2 w / w%, or about 0.2 to about 1 w / w%. The proportion of this stabilizing composition is important to provide the necessary protection for the stabilized elastomeric composition during storage and transportation. A storage stable composition requires little change in Mooney viscosity over extended storage periods, e.g., up to one year at 40°C. The stabilizing composition may be added during or after polymerization. Preferably, the stabilizing composition is added after polymerization.

[0026] According to a fourth aspect of the present invention, there is provided a process for stabilising an article made using an elastomeric material, the process comprising incorporating or applying to the elastomeric material a stabilising composition of the present invention. For clarity, all features relating to the stabilized compositions of the present invention also relate to the stabilized elastomeric compositions, stabilized articles, and processes for stabilizing articles, as appropriate, and vice versa. The present invention will now be more specifically described with reference to the following non-limiting examples.

[0027] Example Table 1 outlines the details regarding the different stabilizing ingredients used in the stabilizing composition. Hereafter, the stabilizing ingredients will simply be referred to using the name listed in the "Abbreviation" column. [Table 1] TIFF0007749464000006.tif39156 Symbols in Table 1: Component A: Phosphite antioxidant Component B: Amine antioxidant Component C: Phenolic antioxidant Component D: Sulfur-containing antioxidant As will be apparent to one of ordinary skill in the art, certain materials (e.g., Rowinox® 520, CAS 110553-27-0) may be included in one or more of ingredient categories A, B, C, and D, which are defined as necessary ingredients of the present invention. Thus, Rowinox® 520 may be recognized as ingredient C and / or ingredient D in accordance with the present invention.

[0028] Table 2 shows the various stabilizing compositions that were prepared, with the percentage amounts in the table being the weight percent of the total stabilizing composition and the amount of stabilizing composition applied in parts by weight (phr). [Table 2] Examples A, B, C, and D are comparative examples that do not contain any amine component, and Example D represents an industry standard. Examples 1-10 are in accordance with the present invention.

[0029] Sample preparation Various mixtures of antioxidants were prepared according to the compositions summarized in Table 2. The antioxidant blends of each example (approximately 60 g) were melted and mixed together. The mixture was then heated to 70° C., and oleic acid was added and mixed together. KOH solution (13.3 w / w%) (approximately 48 g) was then slowly added to the mixture and stirred at high speed to ensure complete mixing and emulsion formation. The mixing speed was then reduced, and approximately 152 g of hot deionized water was added. The resulting antioxidant emulsion had a solids content of approximately 20 w / w%. The examples demonstrate the stability that can be achieved by utilizing various stabilizing compositions for ESBR. An antioxidant emulsion was added to the ESBR latex. After mixing, the ESBR latex sample was coagulated using a standard salt-acid coagulation system. More specifically, the sample was coagulated with 2% calcium chloride. The latex was then added dropwise to a 2% calcium chloride solution, and the rubber was transferred to fresh water. The rubber was washed three times while squeezing. The rubber was then dried in a vacuum oven for 16 hours at 50°C. Any remaining water was then removed using a HAAKE® internal mixer at 105°C for 2 minutes. A two-roll mill was used to make the elastomer more uniform. The elastomers were oven aged at 100°C and measurements were recorded every 24 hours for 4 days (Yellowness Index) and 6 days (Mooney Viscosity).

[0030] Test conditions color stability First, the sample was placed in a compression mold at 100°C for 5 minutes. The resulting ESBR sheet was 1 mm thick. Discoloration was measured using a colorimeter as a Yellowness Index (YI). Approximately 4 g of elastomer was taken for each YI measurement. YI values ​​were recorded at time 0 and every 24 hours thereafter, measured as defined in ASTM E313. The five measurements were averaged. The lower the YI value, the less discoloration the composition had. The results are shown in Table 3. [Table 3] Stabilized compositions A and B represent comparative examples that do not utilize an amine antioxidant. Example D represents an industry standard containing L520. The results show that the ESBR samples stabilized with the stabilizing composition according to the present invention (Examples 1-6) exhibit less discoloration than the industry standard. ESBR samples stabilized with the stabilizing composition according to the present invention have a lower initial Yellowness Index at day 0 and a lower Yellowness Index value at day 4. Thus, ESBR samples using stabilizing compositions consistent with the present invention exhibit excellent color retention and can be stored for extended periods without color change.

[0031] Mooney Viscosity Approximately 20 g of sample was taken for each example for Mooney Viscosity testing. Mooney Viscosity was measured using standard method ASTM D1646, (1+4)T100°C. Mooney Viscosity values ​​were recorded at time 0 and every 24 hours thereafter. [Table 4] * The date crosslinking begins for ESBR. If degradation due to crosslinking dominates over chain scission, an overall increase in Mooney viscosity is expected. Degradation of ESBR is dependent on crosslinking. Elastomer structures degrade primarily through two different degradation mechanisms: chain scission and crosslinking. Chain scission generally occurs early in the degradation process and can decrease Mooney viscosity. Crosslinking generally occurs later in the process and increases Mooney viscosity. It is theorized that Example 8 exhibits slightly higher initial chain scission than the other examples, but subsequently exhibits a relatively smaller fluctuation in Mooney viscosity, as seen from days 2 to 6, compared to the comparative examples. A small change in Mooney viscosity value over time indicates the structural integrity of the elastomer and minimal degradation. The examples according to the invention have Mooney viscosities that are superior to the comparative examples at equivalent loads and are comparable to or superior to the comparative examples at lower load levels. Thus, the examples containing the stabilized compositions according to the present invention clearly exhibit superior Mooney viscosity retention, surpassing Comparative Examples A to D. These stabilized compositions have better storage stability performance and superior retention of physical properties. The examples according to the invention have a smaller degree of variation in Mooney viscosity from day 0 to day 6. As can be seen from the results, the maximum % variation for the examples according to the invention is significantly smaller than that of the comparative examples. Thus, the examples containing the stabilized composition according to the present invention clearly have better Mooney viscosity retention and smaller changes than Comparative Examples A-D.

[0032] Samples of Examples 9 and 10 were taken for Mooney Viscosity testing. Mooney Viscosity values ​​are measured using standard method ASTM D1646, (1+4)T100°C. Mooney Viscosity values ​​are recorded at 0 hours, then 12, 24, 36, and 72 hours. [Table 5] Both Examples 9 and 10 contain stabilized compositions in accordance with the present invention. Example 10 exhibits significantly less variability in Mooney viscosity from 0 to 72 hours. As can be seen from the results, the addition of component D to the stabilized composition significantly increases stability and reduces fluctuations in Mooney viscosity. Thus, the example (Example 10) containing the four-component stabilized composition according to the present invention clearly exhibits superior Mooney viscosity retention and smaller fluctuations. This stabilized composition has better storage stability performance and superior retention of physical properties. Because elastomer converters typically standardize elastomer processing conditions for mass production, variations in Mooney viscosity can lead to varying properties in the final article, resulting in inconsistent quality, which is undesirable. Accelerated heat aging tests simulate the change in Mooney viscosity during various storage and shipping conditions, which indicates to elastomer producers how stable their elastomers are. Thus, the increased stability and reduced variability in Mooney viscosity when using the stabilized compositions according to the present invention is beneficial to the user and results in more consistent product quality. Another aspect of the present invention may be as follows. [1] a. a first stabilizing component comprising at least one phosphite antioxidant; b. a second stabilizing component comprising at least one amine antioxidant; and c. a third stabilizing component comprising at least one phenolic antioxidant; 1. A stabilizing composition for elastomers comprising: [2] The stabilizing composition according to [1], wherein when added to an elastomer, the Mooney viscosity of the elastomer (measured in accordance with ASTM D1646) varies less over a heat aging period of 6 days at 100°C than the same elastomer to which the same stabilizing composition not containing any amine component has been added in an equivalent w / w amount. [3] The stabilized composition according to [1] or [2], further comprising a fourth stabilizing component comprising at least one sulfur-containing antioxidant. [4] The stabilized composition according to any one of [1] to [3], wherein the phenolic antioxidant comprises a hindered phenolic antioxidant. [5] The stabilized composition according to any one of [1] to [4], wherein the phenolic antioxidant is present in the stabilized composition in an amount of about 5 to about 70% by weight of the stabilized composition, about 10 to about 60% by weight of the stabilized composition, about 15 to about 55% by weight of the stabilized composition, about 20 to about 50% by weight of the stabilized composition, or about 20 to about 40% by weight of the stabilized composition. [6] The phosphite antioxidant comprises a triaryl phosphite and may comprise triphenyl phosphite; and / or The stabilized composition according to any one of [1] to [5], wherein the phosphite antioxidant is an antioxidant that does not have nonylphenyl. [7] the phosphite antioxidant is present in an amount greater than about 40% by weight of the stabilized composition; and / or the phosphite antioxidant is present in an amount of from greater than about 40% to about 60, about 65, about 70, about 75, about 80, about 85, about 90, or about 95% by weight of the stabilized composition; and / or [6] The stabilized composition of any one of [1] to [6], wherein the phosphite antioxidant is present in an amount of about 42 to about 75% by weight of the stabilized composition, about 45 to about 70% by weight of the stabilized composition, or about 50 to about 65% by weight of the stabilized composition. [8] The stabilized composition according to any one of [1] to [7], wherein the phosphite antioxidant is liquid at a temperature of 50°C or less, optionally 30°C or less, optionally 25°C or less, and at atmospheric pressure, i.e., 101.325 kPa. [9] The stabilized composition according to any one of [1] to [8], wherein the amine antioxidant is a secondary amine.

[10] The stabilized composition according to any one of [1] to [9], wherein the amine antioxidant contains at least one aromatic group.

[11] The stabilized composition according to any one of [1] to

[10] , wherein the amine antioxidant comprises 4,4'-bis(α,α-dimethylbenzyl)diphenylamine and / or butylated octylated mixed diphenylamine.

[12] The stabilized composition according to any one of [1] to

[11] , wherein the amine antioxidant is present in the stabilized composition in an amount of about 1 to about 40% by weight of the stabilized composition, about 1 to about 30% by weight of the stabilized composition, about 5 to about 25% by weight of the stabilized composition, or about 7 to about 20% by weight of the stabilized composition.

[13] The ratio of the phosphite antioxidant to the amine antioxidant and the phenolic antioxidant is (about 35 to about 70): (about 1 to about 30): (about 15 to about 35); or (about 45 to about 65): (about 5 to about 25): (about 15 to about 30); or (about 50 to about 65):(about 7 to about 20):(about 20 to about 30), The stabilized composition according to any one of [1] to

[12] above.

[14] The ratio of the phosphite antioxidant to the amine antioxidant, the phenolic antioxidant, and the sulfur-containing antioxidant in the stabilized composition is (about 35 to about 70): (about 1 to about 30): (about 15 to about 35): (about 0 to about 20); or (about 45 to about 65): (about 5 to about 25): (about 15 to about 30): (about 1 to about 15); or The stabilized composition according to any one of [3] to

[12] , wherein the molecular weight is (about 50 to about 65):(about 7 to about 20):(about 20 to about 30):(about 1 to about 5).

[15] The stabilized composition according to any one of [1] to

[14] , which is a liquid composition at a temperature of 50°C or less, optionally 30°C or less, optionally 25°C or less, and at atmospheric pressure, i.e., 101.325 kPa.

[16] The stabilized composition according to any one of [1] to

[15] , which, when added to an elastomer, has a maximum % variation in the Mooney viscosity of the elastomer (measured according to ASTM D1646) of less than 30%, less than 25%, less than 20%, less than 16%, or less than 10% over a 6-day period.

[17] The stabilized composition according to any one of [1] to

[16] , wherein when added to an elastomer, after 4 days the yellowness index value of the elastomer (measured according to ASTM E313) is less than 45, less than 40, less than 37, less than 35, or less than 30.

[18] Use of the stabilizing composition according to any one of [1] to

[17] above for stabilizing an elastomer material.

[19] a. Elastomer materials b. The stabilized composition according to any one of [1] to

[17] above 1. A stabilized elastomeric composition comprising:

[20] The elastomeric material comprises natural rubber and / or synthetic rubber; and / or The stabilized elastomer composition according to

[19] , wherein the elastomer material is an emulsion polymerization product.

[21] The stabilized elastomer composition according to

[19] or

[20] , wherein the elastomer material comprises a butadiene-based elastomer.

[22] The stabilized elastomer composition according to

[21] , wherein the butadiene-based elastomer comprises at least one of styrene-butadiene, polybutadiene, nitrile rubber, and polychloroprene.

[23] The stabilized elastomer composition according to any one of

[19] to

[22] , wherein the stabilizing composition is added to the elastomer material in an amount of about 0.01 to about 5 w / w%, about 0.05 to 3 w / w%, about 0.1 to 2 w / w%, or about 0.2 to 1 w / w%.

[24] A practical product comprising the stabilized elastomer composition according to any one of

[19] to

[23] .

[25] A method for stabilizing an article made using an elastomeric material, comprising incorporating or applying the stabilizing composition of any one of [1] to

[17] to the elastomeric material.

Claims

1. a. a first stabilizing component comprising at least one phosphite antioxidant, the phosphite antioxidant being a nonylphenyl-free antioxidant and comprising a triaryl phosphite; b. a second stabilizing component comprising at least one amine antioxidant; and c. a third stabilizing component comprising at least one phenolic antioxidant; A stabilizing composition for elastomers comprising: the phosphite antioxidant is present in an amount greater than 40% by weight of the stabilized composition; The stabilized composition is a liquid composition at 50°C or below and atmospheric pressure, i.e., 101.325 kPa.

2. 10. The stabilized composition of claim 1, wherein the phosphite antioxidant comprises triphenyl phosphite.

3. 10. The stabilized composition of claim 1, wherein the phosphite antioxidant comprises at least two different triaryl phosphites.

4. the at least two different triaryl phosphites each have the structure of formula (III): 【Chemical 1】 In the formula, R 7 , R 8 and R 9 4. The stabilized composition of claim 3, wherein n is independently selected from methyl and ethyl groups and n is 0, 1, 2, or 3.

5. 5. The stabilized composition of claim 4, wherein the at least two different triaryl phosphites are tris(4-tert-pentylphenyl)phosphite; tris(2,4-di-tert-pentylphenyl)phosphite; bis(4-tert-pentylphenyl)-2,4-di-tert-pentylphenyl phosphite; bis(2,4-di-tert-pentylphenyl)-4-tert-pentylphenyl phosphite; or a mixture thereof.

6. 6. The stabilized composition of any one of claims 1 to 5, which when added to an elastomer causes the Mooney viscosity (measured in accordance with ASTM D1646) of the elastomer to vary less over a heat aging period of 6 days at 100°C than the same elastomer to which the same stabilized composition without any amine component has been added in an equivalent w / w amount.

7. 7. The stabilized composition of claim 1, further comprising a fourth stabilizing component comprising at least one sulfur-containing antioxidant.

8. 8. The stabilized composition of claim 7, wherein the sulfur-containing antioxidant comprises one or more sulfur-containing phenolic antioxidants.

9. 9. The stabilized composition of claim 8, wherein the sulfur-containing phenolic antioxidant is 4,6-bis(octylthiomethyl)-o-cresol; 2,2'-thiodiethylenebis[3(3,5-di-t-butyl-4-hydroxyphenyl)propionate]; 2,4-bis(dodecylthiomethyl)-6-methylphenol; or a mixture thereof.

10. 10. The stabilized composition of claim 1, wherein the phenolic antioxidant comprises a hindered phenolic antioxidant.

11. 11. The stabilized composition of claim 1, wherein the phenolic antioxidant is present in the stabilized composition in an amount of from 15 to 55% by weight of the stabilized composition.

12. 12. The stabilized composition of any one of claims 1 to 11, wherein the phosphite antioxidant is a liquid at a temperature of 50°C or less and at atmospheric pressure, i.e., 101.325 kPa.

13. 13. The stabilized composition of claim 1, wherein the amine antioxidant is a secondary amine.

14. 14. The stabilized composition of claim 1, wherein the amine antioxidant comprises at least one aromatic group.

15. 15. The stabilized composition of any one of claims 1 to 14, wherein the amine antioxidant comprises 4,4'-bis(α,α-dimethylbenzyl)diphenylamine) and / or butylated octylated mixed diphenylamines.

16. 16. The stabilized composition of claim 1, wherein the amine antioxidant is present in the stabilized composition in an amount of from 1 to 40% by weight of the stabilized composition.

17. The ratio of phosphite antioxidant to amine antioxidant and phenolic antioxidant is (42 to 70): (1 to 30): (15 to 35), 17. The stabilized composition of any one of claims 1 to 16.

18. The ratio of the phosphite antioxidant to the amine antioxidant and the phenolic antioxidant is (45 to 65): (5 to 25): (15 to 30), 17. The stabilized composition of any one of claims 1 to 16.

19. The ratio of phosphite antioxidant to amine antioxidant, phenolic antioxidant, and sulfur-containing antioxidant in the stabilized composition is 17. The stabilized composition of any one of claims 7 to 16, wherein the ratio is (42 to 70):(1 to 30):(15 to 35):(0 to 20).

20. The stabilized composition of claim 20, wherein the ratio of phosphite antioxidant to amine antioxidant, phenolic antioxidant, and sulfur-containing antioxidant is:

17. The stabilized composition of any one of claims 7 to 16, wherein the ratio is (45 to 65):(5 to 25):(15 to 30):(1 to 15).

21. 21. The stabilized composition of any one of claims 1 to 20, which is a liquid composition at a temperature of 30°C or less and at atmospheric pressure, i.e., 101.325 kPa.

22. 22. The stabilized composition of any one of claims 1 to 21, which, when added to an elastomer, has a maximum % variation in the Mooney viscosity (measured according to ASTM D1646) of the elastomer over a 6 day period of less than 30%.

23. 23. The stabilized composition of any one of claims 1 to 22, which, when added to an elastomer, after 4 days causes the elastomer to have a Yellowness Index value (measured according to ASTM E313) of less than 45.

24. 24. Use of a stabilizing composition according to any one of claims 1 to 23 for stabilizing an elastomeric material.

25. a. Elastomer material b. A stabilized composition according to any one of claims 1 to 23.

1. A stabilized elastomeric composition comprising:

26. the elastomeric material comprises natural rubber and / or synthetic rubber; and / or 26. The stabilized elastomeric composition of claim 25, wherein the elastomeric material is an emulsion polymerization product.

27. 27. The stabilized elastomeric composition of claim 25 or claim 26, wherein the elastomeric material comprises a butadiene-based elastomer.

28. 28. The stabilized elastomeric composition of claim 27, wherein the butadiene-based elastomer comprises at least one of styrene butadiene, polybutadiene, nitrile rubber, or polychloroprene.

29. 29. The stabilized elastomeric composition of any one of claims 25 to 28, wherein the stabilizing composition is added to the elastomeric material in an amount of 0.01 to 5 w / w%.

30. 30. A utility article comprising the stabilized elastomeric composition of any one of claims 25 to 29.

31. 24. A method of stabilizing an article made with an elastomeric material, comprising incorporating or applying to the elastomeric material a stabilizing composition of any one of claims 1 to 23.

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