CA2026900A1

CA2026900A1 - Stabilised organic material

Info

Publication number: CA2026900A1
Application number: CA 2026900
Authority: CA
Inventors: Samuel Evans; Paul Dubs
Original assignee: Ciba Geigy AG
Current assignee: Novartis AG
Priority date: 1989-10-06
Filing date: 1990-10-04
Publication date: 1991-04-07
Also published as: JPH03207788A; EP0421932A1

Abstract

Stabilised organic material Abstract of the disclosure A composition comprising a) an organic material which is susceptible to degradation induced by oxidation, heat and actinic radiadon, b) at least one compound of formula I
(I) wherein X1 is a sulfur atom or C1-C12alkylidene, R1 and R2 are each independently of the other hydrogen, C1-C24alkyl, C5-C12cycloalkyl, C5-C7cycloalkyl which is substituted by C1-C4alkyl, or are phenyl or C7-C10phenylalkyl, R3 and R4 are each independently of the other hydrogen or C1-C8alkyl, and c) at least one compound of formula IIa and/or IIb, ,

Description

`~ 2026~

A-17781/+

Stabilised organic material The present invendon relates to composidons comprising a) an organic material which is susceptible to degradadon induced by oxidation, heat and actinic radiadon, b) a bisphenol monoacrylate and c) a bisphenol. The invendon further relates to the use of a composidon containing a bisphenol monoacrylate and a bisphenol for stabilising organic material.

Stabilisers selected from the group of the bisphenols and bisphenol monoacrylates are known and commercially available.

Japanese Patent Kokai Sho 61/159 442 discloses films of a styrene/butadiene block copolymer which contains, inter alia, a bisphenol monoacrylate and a bisphenol.

In-one of its aspects, dhe present invention relates to a composidon comprising .

a) an organic material which is suscepdble to degradadon induced by oxidadon, heat and actinic radiation, b) at least one compound of formula I
: . O R3 R4 ~: ~ ' . Il I I
: OH O C - C = CH
Rl~,XI~"R~

. ' R2 R2 wherein Xl is a sulfur atom or Cl-CI2aLkylidene, Rl and R2 are each independendy of the other hydrogen, Cl-C24aL~cyl, Cs-CI2cycloalkyl, C5-C7cycloaLkyl which is subsdtuted by Cl-C4aLI~yl, or are phenyl or C7-CIOphenylalkyl, R3 and R4 are each independently of the other hydrogen or Cl-C8aL~yl, ~` 2~26~

and c) at least one compound of formula IIa and/or IIb, ~a) ~b) wherein X2 and X3 are each independently of the other a sulfur atom or Cl-CI2aLkylidene, R5 and R6 are each independendy of dhe odher hydrogen, Cl-C24alkyl, Cs-Cl2cycloaLkyl, Cs-C7cycloalkyl which is substituted by Cl-C4aLIcyl, or are phenyl or C7-ClOphenylaLtcyl, ~ ;~
R7 and R8 are each independently of the other Cl-C4aL~cyl, with dhe proviso that the radical -X3 in formula IIb is different from sulfur if the component a) is a styrenelbutadiene block copolymer.

Cl-CI2ALkylidene may be methylene or a ~oup -CHR-, wherein R is preferably straight-chain aL~cyl, most preferably methyl. Methylene is one of the especially preferred meanings of Xl, X2 und X3.

Cl-C24AL~yl is typically methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecylj nonadecyl, eicosyl, heneicosyl, docosyl, tricosyl or tetracosyl.
Cl-CI8AL~yl is preferred. One of the especially preferred meanings of Rl, R2, Rs and R6 is Cl-C4aLkyl, such as methyl or tert-butyl.

Cs-CI2CycloaLlcyl may be cycIopentyl, cyclohexyl, cycioheptyl, cyclooctyl, cyclononyl, cyclodecyl or cyclododecyl. Cs-C7CycloaLl~yl, preferably cyclohexyl, is preferred.

C5-C7CycloaLIcyl which is substituted by Cl-C4aL1cyl may be methylcyclohexyl.

C7-qOPhenylallcyl may be benzyl or phenylethyl.

~ ~ 2 ~

R3 and R4 as Cl-C8alkyl is typically methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl or octyl. Cl-C4Alkyl, more particularly methyl, is preferred.

R7 and R8 as Cl-C4aLkyl is typically methyl, ethyl, propyl, isopropyl, butyl or tert-butyl.
R7 is preferably methyl and R8 is preferably tert-butyl.

Useful compositions are those wherein Xl, X2 and X3 are each independently of one another a sulfur atom or Cl-C4aLlcylidene, Rl, R2, R5 and R6 are each independently of one another Cl-Cl8aLIcyl, Cs-C7cycloalkyl, Cs-C7cycloaL~cyl which is substituted by Cl-C4alkyl, or are phenyl or C7-ClOphenylaLkyl, R3 and R4 are each independendy of the other hydrogen or Cl-C4aL~cyl, and R7 and R8 are each independently of the otherCl-C4alkyl.

Component b) is preferably selected from compounds of formula I, wherein Xl is a sulfur atom, methylene or ethylidene, Rl and R2 are each independently of the other Cl-C4aL~cyl, cyclohexyl, methylcyclohexyl, phenyl or benzyl, and R3 and R4 are each independendy of the odher hydrogen or Cl-C4alkyl.

Particularly preferred compounds of formula I are those wherein Xl is a sulfur atom, methylene or ethylidene, Rl and R2 are each independently of the other Cl-C4alkyl, and R3 and R4 are hydrogen or methyl.

Component c) is preferably selected from compounds of formula IIa, wherein X2 is a sulfur atom, methylene or ethylidene, and Rs and R6 are each independendy of the other Cl-C4allcyl, cyclohexyl, methylcyclohexyl, phenyl or benzyl.

Particularly preferred compounds of formula IIa are dhose wherein X2 is a sulfur atom, methylene or ethylidene, and Rs and R6 are each independently of the other Cl-C4aL~cyl.

Preferred compounds of formula IIb are those wherein X3 is a sulfur atom, and R7 and R8 are each independendy of the other Cl-C4alkyl.

Particularly useful compositions are those in which component b) is selected from the group consisting of r~

.j . .. . .. .

-~ 2~26~

OH O--C - CH= CH2OH O - C - C CH2 (H3C~3C ~ S ~ C(CH3)3(N3C3C ~ S ~ C(CH~3 O O
Il ~ 11 .
OH O - C - CH= CH2 OH O - C - CH= CH2 (H3C3C~CN~4CN3)3 IH3C)3C~IH~C(CH3)3 CH3 CH3 C(CH3)3 C(CH3)3 .
and component c) is selected from the group consisting of ;~

OH OH H3C CH3 -.
(H3C)3C ~ S ~ C(CH3)3 ~ ~
, H ~ S ~ OH

CH3 CH3 (H3C)3C C(CH3 ,::
OH OH OH OH
(H3C)3C~CH~C(CN3)3 (N3C3C~ 2~c(cH3)3 C(CH3)3 C(CH3)3 CH3 CH3 Particularly preferred compositions are those wherein component b) is ." .. , ` . , ,. . ' :. ' '. : ' `" 2~26~J

OH O--C--CH= CH2 (H3C)3C~ 3~C(CH3)3 and component c) is OH OH
(U3ChC~S~C(CU~h Illustrative exarnples of component a) are:

1. Polymers of monoolefins and diolefins, for example polypropylene, polyisobutylene, polybut-l-ene, polymethylpent-l-ene, polyisoprene or polybutadiene, as well as polymers of cycloolefins, for example of cyclopentene or norbornene, polyethylene (which can be uncrosslinked or crosslinked), for example high density polyethylene (HDPE), low density polyethylene (LDPE and linear low density polyethylene (LLDPE).

2. Mixtures of the polymers mendoned under 1), for example mixtures of polypropylene with polyisobutylene, polypropylene with polyethylene (for exarnple PPIHDPE, PP/LDPE) and mixtures of different types of polyethylene (for example LDPE/HDPE).

3 . Copolymers of monoolefims and diolefins with each other or with other vinyl monomers, for example ethylene/propylene copolymers linear low density polyethylene (LLDPE) and mixtures thereof with low density polyethylene (LDPE), propylenelbut-l-ene copolymers, ethylenelhexene copolymers, ethylene/methylpentene copolymers, ethylene,lheptene copolymers, ethylene/octene copolymers, propylenelbutadiene copolymers, isobutylene/isoprene copolymers, ethylene/aLkyl acrylate copolymers, e~ylenelalkyl methacrylate copolymers, ethylene/vinyl acetate or ethylene/acrylic acid copolymers and their salts (ionomers), as well as terpolymers of ethylene with propylene and a diene such as hexadiene, dicyclopentadiene or ''.: `~i:: ~ ,. '', ::` 21D26~

ethylidenenorbornene; and also mixtures of such copolymers with each other and with polymers mentioned in 1) above, for example polypropylene/ethylene propylene copolymers, LDPE/EVA, LDPE/EAA, LLDPE/EVA and LLDPE/EAA.

3a. Hydrocarbon resins (for example Cs-Cg), including hydrogenated modificationsthereof (for example tackifiers).

4. Polystyrene, poly-(p-methylstyrene), poly-(a-methylstyrene).

5. Copolymers of styrene or a-methylstyrene with dienes or acrylic derivatives, for example styrenel[ch]butadiene, styrene/acrylonitrile, styrene/alkylmethacrylate,styrene/butadiene/aLlcylacrylate, styrene/ maleic anhydride, styrene/acrylonitrile/methyl acrylate; mixtures of high impact strength from styrene copolymers and another polymer, for example from a polyacrylate, a diene polymer or an ethylene/propylene/diene terpolymer; and bloel~ copolymers of styrene, for example styrene/butadiene/styrene, styrene/isoprene/styrene, styrene/ethylene/butylene/styrene or styrene/ethylene/propylene/styrene.

6. Graft copolymers of styrene or a-methylstyrene, for example styrene on polybutadiene, styrene on polybutadiene/styrene or polybutadiene/acrylonitrile; styrene and acrylonitrile ` ;
(or methacrylonitrile) on polybutadiene; styrene and maleic anhydride or maleimide on polybutadiene; styrene, acrylonitrile and maleic anhydride or maleimide on polybutadiene;
styrene, acrylonitrile and methyl methacrylate on polybutadiene, styrene and aL~cyl acrylates or methacrylates on polybutadiene, styrene and acrylonitrile on ethylene/propylene/diene teIpolymers, styrene and acrylonitrile on polyaLIcylacrylates or polyaLl~ylmethacrylates, styrene and acrylonitrile on acrylate/butadiene copolymers, as well as mixtures thereof with the copolymers listed under 5), for example the copolymer mixtures known as ABS, MBiS, ASA or AES polymers.

7. Halogenated polymers such as polychloroprene, chlorinated rubbers, chlorinated or sulfochlorinated polyethylene, copolymers of ethylene and chlorinated ethylene, epichlorohydrin homo- and copolymers, preferably polymers of halogenated vinyl compounds, for example poly- vinylchloride, polyvinylidene chloride, polyvinyl fluoride, polyvinylidene fluoride, as well as copolymers thereof, for example vinyl chloride/vinylidene chloride, vinyl chloride/vinyl acetate or vinylidene chloride!vinyl acetate copolymers.

2~26~

8. Polymers derived from a"B-unsaturated acids and derivatives thereof, such as polyacrylates and polymethacrylates, polyacrylamides and polyacrylonitriles.

9. Copolymers of the monomers mentioned under 8) with each other or with other unsaturated monomers, for example acrylonitrile/butadiene copolymers, acrylo-nitrile/aLkylacrylate copolymers, acrylonitrile/aLlcoxyaLlcylacrylate or acrylonitrile/vinyl halide copolymers or acrylonitrile/aL~cylmethacrylate/butadiene terpolymers.

10. Polymers derived from unsaturated alcohols and amines or the acyl derivatives or acetals thereof, such as polyvinyl alcohol, polyvinyl acetate, polyvinyl stearate, polyvinyl benzoate, polyvinyl maleate, polyvinylbutyrate, polyallyl phthalate or polyallylmelamine;
as well as their copolymers with the olefins mentioned in 1) above.

11. Homopolymers and copolymers of cyclic ethers such as polyaLIcylene glycols, polyethylene oxide, polypropylene oxide or copolymers thereof with bisglycidyl ethers.

12. Polyacetals such as polyoxymethylene and those polyoxymethylenes which contain ethylene oxide as a comonomer, polyacetals modified with thermoplastic polyurethanes, acrylates or MBS.

13. Polyphenybne oxides and sulfides and mixtures thereof with polystyrene or polyamides.

14. Polyurethanes which are derived from polyethers, polyesters or polybutadienes carrying terminal hydroxyl groups on the one hand and aliphatic or aromatic polyisocyanates on the other, as well as precursors thereo 15. Polyamides and copolyamides which are derived from diamines and dicarboxylicacids andl[ch]or from arninocarboxylic acids or the corre- sponding lactams, such as polyamîde 4, polyamide 6, polyamide 6/6, 6/10, 6/9, 6/12 and 4/6, polyamide 11, polyamide 12, aromatic polyamides obtained by condensation of m-xylene, diamine and adipic acid; polyamides prepared from hexamethylenediamine and isophthalic and/or terephthalic acid, with or without an elastomer as modifier, for example poly-2,4,4,-trimethylhexamethylene terephthalamide or poly-m-phenylene isophthalamide; blockcopolymers of the aforementioned polyamides with polyolefins, olefin copolymers, -` 2~2~

ionomers or chemically bonded or grafted elastomers; or with polyethers, for example with polyethylene glycol, polypropylene glycol or polytetramethylene glycol; and also polyamides or copolyamides modified with EPDM or ABS, and polyamides condensed during processing (RIM polyamide systems).

16. Polyureas, polyimides and polyamide-imides and polybenz~midazoles.

17. Polyesters derived from dicarboxylic acids and diols and/or from hydroxycarboxylic acids or the corresponding lactones, such as poly-ethylene terephthalate, polybutylene terephthalate, poly-1,4-dimethylolcyclohexane terephthalate, polyhydroxybenzoates as well as block-copolyether esters derived from hydroxyl-terminated polyethers; and also polyesters modified with polycarbonates or MBS.

18. Polycarbonates and polyester carbonates.

19. Polysulfones, polyether sulfones and polyether ketones.

20. Crosslinked polymers which are derived from aldehydes on the one hand and phenols, ureas and melamines on the other hand, such as phenol/formaldehyde resins, urea/formaldehyde resins and melamine/formaldehyde resins.

21. Drying and non-drying aL~yd resins.

22. Unsaturated polyester resins which are derived from copolyesters of saturated and unsaturated dicarboxylic acids with polyhydric alcohols and vinyl compounds as crosslinking agents, and also halogen-containing modifications thereof of low flammability.
, 23. Crosslinkable acrylic resins derived from substituted acrylic esters such as epoxy acrylates, urethan-e acrylates or polyester acrylates.

24. Alkyd resins, polyester resins or acrylate resins which are cross-linked with melamine resins, urea Dsins, polyisocyanates or epoxy resins.

25. Crosslinked epoxy resins which are derived from polyepoxides, for example from bisglycidyl ethers or from cycloaliphatic diepoxides.

` ~ - ` ` 2 ~

26. Natural polymers such as cellulose, rubber, gelatine and chemically modifiedhomologous derivatives thereof such as cellulose acetates, cellulose propionates and cellulose butyrates, or the cellulose ethers, such as methylcellulose; as well as rosins and their derivatives.

27. Mixtures (polyblends) of the aforementioned polymers, for example PP/EPDM, Polyamide 61EPDM or ABS, PVC/EVA, PVS/ABS, PVC/MBS, PC/ABS, PBTP/ABS, PC/ASA, PC/PBT, PVC/CPE, PVC/acrylates, POMJthermoplastic PUR, PC/thermoplastic PUR, POM/acrylate, POM/MBS, PPE/HIPS, PPE/PA 6.6 and copolymers, PA/HDPE, PA/PP, PA/PPE.

28. Naturally occurring and synthetic organic materials which are pure monomericcompounds or mixtures of such compounds, for example mineral oils, animal and vegetable fasts, oil and waxes, or oils, fats and waxes based on synthetic esters (e.g.
phthalates, adipates, phosphates or trimellitates) and also the mixtures of synthetic esters with mineral oils in any weight ratios which are used as spinning compositions, as well as aqueous emulsions of such materials.

29. Aqueous emulsions of natural or synthetic rubber, for exarnple natural latex or latices of carboxylated styrenelbutadiene copolymers.

Component a) is preferably a synthetic polymer, a synthetic oil or a mineral oil. It is most preferred to use polyolefims such as the polymers listed in items l) to 3) above, especially crosslinked polyolefins or polyolefins to be crosslinked, as component a). On account of its melting point, the mixture of components b) and c) is particularly suitable for stabilising crosslinked polyethylene.

The concentration of components b) and c), together, is conveniently 0.0l to l0 %, preferably 0.0l to 5 %, most preferably 0.0l to 2 % or 0.05 to 2 %, based on the total weight of the composition. The ratio of components b) and c) is, for example, 95/5 to 5/95, preferably 80/20 to 60/40, most preferably 75/25 to 65/35, ~or example 75i25 to 70/30 or 70/30 to 65/35.
~ .
In addition to components a), b) and c), the compositions of the invention may further contain conventional additives, for example those listed below.

-`-` 2~6~

1. Antioxidants 1.1. AL~cYlated monophenols, for example 2,6-di-tert-butyl-4-methylphenol, 2-tert-butyl-4,6-dimethylphenol, 2,6-di-tert-butyl-4-ethylphenol, 2,6-di-tert-butyl-4-n-butylphenol, 2,6-di-tert-butyl-4-isobutylphenol, 2,6-dicyclopentyl-4-methylphenol, 2-(a-methylcyclohexyl)- 4,6-dimethylphenol, 2,6-dioctadecyl-4-methylphenol, 2,4,6-tri-cyclohexylphenol, 2,6-di-tert-butyl-4-methoxymethylphenol, 2,6-di-nonyl-4-methyl-phenol.
: .
1.2. ALIcvlated hvdroquinones,for example 2,6-di-tert-butyl-4-methoxyphenol, 2,5-di-tert-butylhydroquinone, 2,5-di-tert-amylhydroquinone, 2,6-diphenyl-4-octadecyl-oxyphenol.

1.3. Hydroxvlated thiodiphenvl ethers, for example 2,2'-thiobis(6-tert-butyl-4-methyl-phenol), 4,4'-thiobis~6-tert-butyl-2-methylphenol).

1.4. AL~cYlidenebisphenols, for example 4,4'-methylenebis(2,6-di-tert-butylphenol), 4,4'-methylenebis(6-tert-butyl-2-methylphenol), 1,1-bis-(S-tert-butyl-4-hydroxy-2-methylphenyl)butane, 2,6-bis(3-tert-butyl-5-methyl-2-hydroxybenzyl)-4-methylphenol, 1,1,3-tris(S-tert-butyl-4-hydroxy-2-methylphenyl)butane, 1,1-bis(S-tert-butyl-4-hydroxy-2-methylphenyl)-3-n-dodecylmercaptobutane, ethylene glycol bis[3,3-bis(3'-tert-butyl-4'-hydroxyphenyl)butyrate], bis(3-tert-butyl-4-hydroxy-S-methyl-phenyl)-dicyclopentadiene, bis[2-(3'-tert-butyl-2'-hydroxy-S'-methyl-benzyl)-6-tert-butyl-4-methylphenyl] tereph~alate.

l.S. Benzvl compounds, for example 1,3,5-tris(3,5-di-tert-butyl-4- hydroxybenzyl)-2,4,6-trimethylbenzene, bis(3,5-di-tert-butyl-4-hydroxybenzyl) sulfide, isooctyl3,5-di-tert-butyl-4-hydroxybenzylmercaptoacetate, bis(A-tert-butyl-3-hydroxy-2,6-dimethylbenzyl) dithiolterephthalate, 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate, 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanurate, dioctadecyl 3,5-di-tert-butyl-4-hydroxybenzylphosphonate, calcium salt of monoethyl 3,5-di-tert-butyl-4-hydroxybenzylphosphonate, 1,3,5-tris-(3,5-dicyclohexyl-4-hydroxybenzyl)isocyanura~e.

1.6. Acvlaminophenols, for example 4-hydroxylauranilide, i-hydroxystearanilide, ; . , -^~` 2~2~

2,4-bis(octylmercapto)-6-(3,5-di-tert-butyl-4-hydroxyanilino)-s-triazine, octyl N-(3,5-di-tert-butyl-4-hydroxyphenyl)carbamate .

1.7. Esters of ~-(3.5-di-tert-butvl-4-hvdroxYphenYl)propionic acid with mono- orpolyhydric alcohols, e.g. with methanol, diethylene glycol, octadecanol, triethylene glycol, 1,6-hexanediol, pentaerythritol, neopentyl glycol, tris(hydroxyethyl) isocyanurate, thiodiethylene glycol, N,N'-bis(hydroxyethyl)oxalyl diamide.

1.8. Esters of ,B-(5-tert-butvl-4-hvdroxv-3-methvlphenvl)propionic acid with mono- or polyhydric alcohols, e.g. with methanol, diethylene glycol, octadecanol, triethylene glycol, 1,6-hexanediol, pentaerythritol, neopentyl glycol, tris~hydroxyethyl) isocyanurate, thiodiethylene glycol, N,N'-bis(hydroxyethyl)oxalyl diamide.

1.9. Esters of 1~-(3,5-dicvclohexvl-4-hYdroxvphenvl)propionic acid with mono- orpolyhydric alcohols, e.g. with methanol, diethylene glycol, octadecanol, triethylene glycol, 1,6-hexanediol, pentaerythritol, neopentyl glycol, tris(hydroxyethyl) isocyanurate, thiodiethylene glycol, N,N'-bis(hydroxyethyl)oxalyl diamide.

1.10. Amides of l~i-(3~5-di-tert-butYl-4-hvdroxvPhenvl)propionic acid e.g.
N,N'-bis(3,5-di-tert-butyl-4-hydroxyphenylpropionyl)hexamethylene-diamine, N,N'-bis(3,5 di-tert-butyl-4-hydroxyphenylpropionyl)trimethylene-diamine, N,N'-bis(3,5~i-tert-butyl-4-hydroxyphenylpropionyl)hydrazine.

2. UV absorbers and li~ht stabilisers 2.1. 2-(2'-Hvdroxyphenv!)benzotriazoles, for example the 5'-methyl, 3',5'-di-tert-butyl, 5'-tert-butyl, 5'-(1,1,3,3-tetramethylbutyl), 5-chloro-3',5'-di-tert-butyl, S-chloro-3'-tert-butyl-5'-methyl, 3~-sec- butyl-5'-tert-butyl, 4'-octoxy, 3',5'-di-tert-amyl and 3',5'-bis(a,c~-dimethylbenzyl) derivative.

2.2. 2-Hvdroxvbenzophenones. for example the 4-hydroxy, 4-methoxy, 4-octoxy, 4-decyloxy, 4-dodecyloxy, 4-benzyloxy, 4,2',4i-trihydroxy and 2'-hydroxy-4,4'-dimethoxyderivative.

2.3. Esters of substituted and unsubstituted benzoic acids, for example, 4-tert-butylphenyl salicylate, phenyl salicylate, octylphenyl salicylate, dibenzoylresorcinol, ,. , . ~ ., ~
.: :, . , : ' , , , . : 1 ~ ' ' bis(4-tert-butylbenzoyl)-resorcinol, benzoylresorcinol, 2,4-di-tert-butylphenyl 3,5-di-tert-butyl-4-hydroxy- benzoate and hexadecyl 3,5-di-tert-butyl-4-hydroxybenzoate.

2.4. Acrvlates, for example ethyl a-cyano-~,~-diphenylacrylate, isooctyl a-cyano-,B"B-diphenylacrylate, methyl a-carbomethoxycinnamate, methyl a-cyano-,~-methyl-p-methoxy-cinnamate, butyl a-cyano-~-methyl-p-methoxy- cinnamate, methyl a-carbo-methoxy-p-methoxycinnamate and N-(,~-carbomethoxy-,~-cyanovinyl)-2-methylindoline.

2.5. Nickel compounds~ for example nickel complexes of 2,2'-thio-bis[4-(1,1,3,3-tetra-methylbutyl)phenol], such as the 1:1 or 1:2 complex, with or without additional ligands such as n-butylamine, triethanolamine or N-cyclohexyldiethanolamine, nickel dibutyl-dithiocarbamate, nickel salts of 4-hydroxy-3,5-di-tert-butylbenzyl-phosphonic acid monoalkyl esters, e.g. of the methyl or ethyl ester, nickel complexes of ketoximes, e.g. of 2-hydroxy-4-methyl-phenyl undecyl ketoneoxime, nickel complexes of 1-phenyl-4-lauroyl-5-hydroxypyrazole, with or without additional ligands.

2.6. Stericallv hindered amines. for example bis(2,2,6,6-tetramethyl-piperidyl) sebacate, bis(l ,2,2,6,6-pentamethylpiperidyl) sebacate, bis( 1 ,2,2,6,6-pentamethylpiperidyl) n-butyl-3,5-di-tert-butyl-4-hydroxy-benzylmalonate, the condensation product of 1-(2-hydroxyethyl)-2,2,6,6-tetramethyl-4-hydroxypiperidine and succinic acid, the condensation product of N,N'-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylenediamine and 4-tert-octylamino-2,6-dichloro-1,3,5-triazine, tris(2,2,6,6-tetramethyl-4-piperidyl) nitrilotriacetate, tetrakis(2,2,6,6-tetramethyl-4- piperidyl)-1,2,3,4-butane-tetracarboxylate, 1,1 '-(1 ,2-ethanediyl)bis-(3,3,5,5-tetramethylpiperazinone).

2.7. Oxalyl diamides. for example 4,4'-dioctyloxyoxanilide, 2,2'-dioctyloxy-S,S'-di-tert-butoxanilide, 2,2'-didodecyloxy-S,S'-di-tert-butoxanilide, 2-ethoxy-2'-ethyloxanilide, N,N'-bis(3-dimethylaminopropyl)oxalamide, 2-ethoxy-S-tert-butyl-2'-ethyloxanilide and its mixture with 2-ethoxy-2'-ethyl-5,4'-di-tert-butoxanilide and mixtures of ortho- and para-methoxy-disubstituted oxanilides and mixtures of o- and p-ethoxydisubstituted oxanilides.

2.8. 2-(2-HydroxvphenYI~-1,3,5-triazines. for example 2,4,6-tris(2-hydroxy-4-octyloxy-phenyl)-1,3,5-triazine, 2-(2-hydroxy-4-octyloxy-phenyl)-4,6-bis(2,4-dimethylphenyl)-1 ,3,5-triazine, 2-(2,4-dihydroxy-phenyl)-4,6-bis(2,4-dimethylphenyl)- 1 ,3,5-triazine, 2,4-bis(2-hydroxy-4-propyloxyphenyl)-6-(2,4-dimethylphenyl)- 1 ,3,5-triazine, 2~26~

2-(2-hydroxy-4-octyloxyphenyl)-4,6-bis(4-methylphenyl)-1,3,5-t;iazine, 2-(2-hydroxy-4-dodecyloxyphenyl)-4,6-bis(2,4-dimethylphenyl)- 1 ,3,5-triazine.

3. Metal deactivators, for example N,N'-diphenyloxalyl diamide, N-salicylal-N'-salicyloylhydrazine, N,N'-bis(salicyloyl)hydrazine, N,N'-bis(3,5-di-tert-butyl-4-hydroxyphenylpropionyl)hydrazine, 3-salicyloyl- amino-1,2,4-t.iazole, bis(benzylidene)oxalic dihydrazide.

4. Phosphites and phosphonites. for example triphenyl phosphite, diphenylaL~yl phosphites, phenyldiaLkyl phosphites, tris(nonylphenyl) phosphite, trilauryl phosphite, trioctadecyl phosphite, distearyl pentaerythritol diphosphite, tris(2,4-di-tert-butylphenyl) phosphite, diisodecyl pentaerythritol diphosphite, bis(2,4-di-tertbutylphenyl) penta-erythritol diphosphite, tristearyl sorbitol triphosphite, tetrakis-(2,4-di-tert-butylphenyl) 4,4'-biphenylene diphosphonite, 3,9-bis(2,4-di-tert-butylphenoxy)-2,4,8,10-tetraoxa-3 ,9-diphosphaspiro[S .S]undecane.

5. Peroxide scavengers~ for example esters of ,B-thiodipropionic acid, for example the lauryl, stearyl, myristyl or tridecyl esters, mercaptobenzimidazole or the zinc salt of 2-mercaptobenzimidazole, zinc dibutyldithiocarbamate, dioctadecyl disulfide, pentaerythritol tetrakis(,B-dodecylmercapto)propionate.

6. Polvamide stabilisers. for example, copper salts in conjunction with iodides and/or phosphorus compounds and salts of divalent manganese.
- . ' 7. Basic co-stabilisers. for example, melamine, polyvinylpyrrolidone, dicyandiamide, triallyl cyanurate, urea derivatives, hydrazine derivadves, amines, polyamides, polyurethanes, alkali metal salts and alkaline earth metal salts of higher fatty acids for example calcium stearate, zinc stearate, magnesium stearate, sodium ricinoleate and potassium palmitate, antimony pyrocatecholate or zinc pyrocatecholate.

8. Nucleatin~ a~ents, for example, 4-tert-butylbenzoic acid, adipic acid, diphenylacetic acid.

9. Fillers and reinforcin~ agents. for example calcium carbonate, silicates, glass fibres, asbestos, talc, kaolin, mica, barium sulfate, metal oxides and hydroxydes, carbon black, graphite.

~`` 202~

10. Other additives. for example, plasticisers, lubricants, emulsifiers, pigments, fluorescent whitening agents, flameproofing agents, antistatic agents and blowing agents.

The conventional additives are added, for example, in concentrations of 0.0l to 10 %, based on the total weight of the composition.

Components b) and c) can be added singly or in admuxture to the material to be stabilised [component a)]. If the material to be stabilised is a po1ymer, components b) and c) can also be added before or during the polymerisation or crosslinking. The incorporation of components b) and c) as well as further additives in a polymeric material can also be effected, for example, before or during the shaping to moulded articles, or also by applying a solution or dispersion of the compounds to a polymeric material and subsequently evaporating the solvent.

Components b? and c) can also be added to the material to be stabilised singly or together in the form of a masterbatch which contains them, for example, in a concentration of 2.5 to 25 % by weight.

The stabilised material may be used in a wide range of presentation, for exarnple as sheets, filaments, ribbons, moulding compounds, profiles or as binders for paints, adhiesives or puffles, or as~insulating material for wires, especially for power cables.

The compounas of formulae I, lIa and m are known and, if they are not commercially available, can be prepared by methods known to the skilled person, for example as described in US patent specification 3 984 372.

In another of its aspects, the invention relates to the use of a mixture comprising at least one compound of formula I and at least one compound of forrnula IIa and/or IIb for stabilising an organic material against degradation induced by oxidation, heat and actinic radiation, with the proviso that the radical X3 in formula lIb is different from sulfur if the organic material is a styrene/butadiene block copolymer.

The invention is illustrated in more detail by the following Examples.

Example l: 26 g of polyethylene (density = (0.926 - 0.929)g/cm3; melt index = (0.15 -..
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0.30)g/10 min at 190C and 2.16 kg) are rnixed with 0.28 % by weight of 2,2'-thio-bis-[6-tert-butyl-4-methylphenol]monoacrylate and 0.12 % by weight of 2,2'-thio-bis[6-tert-butyl-4-methylphenol~ and plasticised in a Brabender plastograph for 5 minutes at 125C.
Then a further 12 g of polyethylene are added together with 2 % by weight of dicumyl peroxide as radical former, and the mixture is kneaded for 5 minutes at 125C. The resultant polymer melt is pressed at 125C in a press to a 1 mm sheet. In a second press, the polymer of which the sheet consists is crosslinked for lS minutes at 180C. In a third press, the sheet is cooled to room temperature. Dumbbell-shaped samples are thenpunched from ~his sheet in accordance with DIN 52 504. For determining the resistance to ageing, the specimens are hung in a circulating air drier heated to 150C and subjected at regular intervals to an elongation at load test. The results show an excellent stabilising effect.

Example 2: 26 g of polyethylene (density = 0.92 g/cm3; melt index = 2 g/10 min at 190C
and 2.16 kg) are mixed with 0.14 % by weight of 2,2'-thio-bis[6-tert-butyl-4-methylphenol]monoacrylate and 0.06 % by weight of 2,2'-thio-bis[6-tert-butyl-4-methylphenol] and plasticised in a Brabender plastograph for 3 minutes at 130C. Then a further 12 g of polyethylene are added together with 1.8 % by weight of dicumyl peroxide as radical former, and the mixture is kneaded for 7 minutes at 130C. The resultant polymer melt is pressed at 130C in a press to a 1 mm sheet. In a second press, the polymer of which the sheet consists is crosslinked for 15 rninutes at 180C. In a third ~ -press, the sheet is cooled to room temperature. Dumb-bell shaped samples are then punched from this sheet in accordance with DIN 52 504. For determining the resistance to àgeing, the specimens are hung in a circulating air drier heated to 150C and tested at regular intervals for decomposition, which occurs in this case after 96 hours.

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Claims

1. A composition comprising a) an organic material which is susceptible to degradation induced by oxidation, heat and actinic radiation, b) at least one compound of formula I
(I) wherein X1 is a sulfur atom or C1-C12alkylidene, R1 and R2 are each independently of the other hydrogen, C1-C24alkyl, C5-C12cycloalkyl, C5-C7cycloalkyl which is substituted by C1-C4alkyl, or are phenyl or C7-C10phenylalkyl, R3 and R4 are each independently of the other hydrogen or C1-C8alkyl, and c) at least one compound of formula IIa and/or IIb, , (IIa) (IIb) wherein X2 and X3 are each independently of the other a sulfur atom or C1-C12alkylidene, R5 and R6 are each independently of the other hydrogen, C1-C24alkyl, C5-C12cycloalkyl, C5-C7cycloalkyl which is substituted by C1-C4alkyl, or are phenyl or C7-C10phenylalkyl, R7 and R8 are each independently of the other C1-C4alkyl, with the proviso that the radical X3 in formula IIb is different from sulfur if the component a) is a styrene/butadiene block copolymer.

2. A composition according to claim 1, wherein X1, X2 and X3 are each independently of one another a sulfur atom or C1-C4alkylidene, R1, R2, R5 and R6 are each independently of one another C1-C18alkyl, C5-C7cycloalkyl, C5-C7cycloalkyl which is substituted by C1-C4alkyl, or are phenyl or C7-C10phenylalkyl, R3 and R4 are each independently of the other hydrogen or C1-C4alkyl, and R7 and R8 are each independently of the other C1-C4alkyl.

3. A composition according to claim 1, wherein X1 is a sulfur atom, methylene orethylidene, R1 and R2 are each independently of the other C1-C4alkyl, cyclohexyl, methylcyclohexyl, phenyl or benzyl, and R3 and R4 are each independently of the other hydrogen or C1-C4alkyl.

4. A composition according to claim 1, wherein X1 is a sulfur atom, methylene orethylidene, R1 and R2 are each independently of the other C1-C4alkyl, and R3 and R4 are hydrogen or methyl.

5. A composition according to claim 1, wherein X2 is a sulfur atom, methylene orethylidene, and R5 and R6 are each independently of the other C1-C4alkyl, cyclohexyl, methylcyclohexyl, phenyl or benzyl.

6. A composition according to claim 1, wherein X2 is a sulfur atom, methylene orethylidene, and R5 and R6 are each independently of the other C1-C4alkyl.

7. A composition according to claim 1, wherein X3 is a sulfur atom, and R7 and R8 are each independently of the other C1-C4alkyl.

8. A composition according to claim 1, wherein component b) is selected from the group consisting of , or and component c) is selected from the group consisting of , , or .

9. A composition according to claim 1, wherein component b) is and component c) is .

10. A composition according to claim 1, wherein component a) is a synthetic polymer, a synthetic oil or a mineral oil.

11. A composition according to claim 1, wherein component a) is a polyolefin.

12. A process for stabilising an organic material against degradation induced by oxidation, heat and actinic light, which comprises incorporating in said organic material a mixture comprising at least one compound of formula I according to claim 1 and at least one compound of formula IIa and/or IIb according to claim 1, with the proviso that the radical X3 in formula IIb is different from sulfur if the organic material is a styrene/butadiene block copolymer.