SK67095A3 - Maleic acid imide alpha-olefin copolymers and their use as light protection agents and stabilizers for organic materials - Google Patents

Abstract

Described are maleic acid imide alpha -olefin copolymers with a mean molecular weight of 1,000 to 50,000, built up of structural units of the formula I, R<1> being a tetramethylpiperidinyl grouping of the formula II in which R<3> is hydrogen, C1 to C6 alkyl, formyl, C2 to C6 alkanoyl, C1 to C12 alkoxy, C5 to C6 cycloalkoxy, cyanomethyl, 2-Hydroxyethyl, benzyl or a group of the formula -CR<4> = CH-CO-OR<5>, R<4> being hydrogen,C1 to C6 alkyl or a group of the formula -CO-OR<5>, and r<5> being C1 to C18 alkyl, C5 to C8 cycloalkyl, C7 to C18 aralkyl, phenyl or tolyl, where R<1> can also denote, in a quantity of up to 8 mole % relative to II, hydrogen, C1 to C22 alkyl or C5 to C8 cycloalkyl, and R<2> is a mixture of C14 to C28 alkyl groups, two of these alkyl groups, which may not differ from each other by more than two C-atoms, constituting at least 30 % of this mixture. The copolymers described are suitable for use as light-protection agents and stabilizers for organic materials, particularlyplastics and paints.

Description

(57) Annotation:

Described is a copolymer of maleimide and α-olefin, built from structural units of formula I, in which the meaning of each symbol is given in the description of the invention. The copolymer described has an average molecular weight of from 1000 to 50,000 and is suitable as a light protection agent and as a stabilizer for organic materials, especially plastics and lacquers.

CH ₂ - CH t

R2 (I)

Copolymers! &! ΙΜ / $ (Λ / a and α-olefin, their use as agents to protect against ile and stabiliz stabilizer01 / into organic material /

Technical field

The present invention relates to novel maleic acid and α-olefin copolymers, a process for their preparation, their use as light protection agents and stabilizers for organic material, in particular for plastics and varnishes, as well as organic material which is stabilized by these copolymers. .

BACKGROUND OF THE INVENTION

As is known, organic materials, especially plastics and lacquers, decompose very rapidly, especially under the influence of light. This decomposition usually results in yellowing, discoloration, cracking or embrittlement of the material. Thus, with light-stabilizing agents and stabilizers, satisfactory protection against the decomposition of organic material by light, oxygen and heat should be obtained.

DE-C 30 24 525 (1) thus relates to a cationic polymer of maleic anhydride consisting of 0 to 90 mol%. optionally substituted ethylene units up to 10 to 100 mol%; maleic anhydride units which are _? imidated up to 67 to 95% with 4-amino-2,2,6,6-tetramethylpiperidine. This polymer is suitable for stabilizing plastics against photodegradation and heat decomposition. Substituted ethylene units used include, but are not limited to, C 1 -C 20 alkyl radicals, i.e., α-olefins having 3 to 22 carbon atoms are suitable monomer components. The copolymer described comprises maleic anhydride units and ethylene units preferably in a 1: 1 ratio and preferably has a molecular weight of from 1000 to 2,000,000.

GB-A 2 145 100 (2) relates to a copolymer made of

N-polyalkylpiperidyl substituted maleic imides, e.g. from -piperidyl) maleic carbon atoms. This light-protection of the imide of N- (2,2,6,6-tetramethyl-4a α-olefin, which contains 3 to 20 copolymers) is suitable as a composition for plastics, such as 1-dodecene as α-olefins. The described copolymer has a number average molecular weight of from 1000 to 50,000, preferably from 1000 to 5000.

DD-A 262 439 (3) relates to a method of stabilizing polymers against light and oxidizing terpolymers, multipolymers or polymers made from maleic acid derivatives containing polyalkylpiperidine, e.g. from an acid imide

N- (2,2,6,6-tetramethyl-4-piperidyl) maleic acid, as the first component, optionally substituted ethylene units, e.g. α-olefin having 3 to 20 carbon atoms as the second component and maleic anhydride, maleic amide or maleic imide as the third component, wherein the compounds of the third component may still be substituted by O- or N-alkyl, -aralkyl or -phenyl . The polymers described have a relative molecular weight of from 800 to 150,000, preferably from 800 to 12,000.

Such prior art compositions are often unsatisfactory due to their low compatibility with plastics, the low duration of the protective effect, the actual coloring of the substance, the tendency to volatility and the thermal decomposition of the stabilizer when processed at elevated temperature.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to provide light stabilizers or stabilizers that provide more effective protection for organic material.

For this and the α-olefin, maleic acid copolymers exposed from structural units of formula I have been invented

In which

R ¹ represents a tetramethylpiperidyl radical of formula II

(II) wherein it represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, formyl, an alkanoyl group having 2 to 6 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, a cycloalkyloxy group having 5 or 6 carbon atoms, cyanomethyl, 2-hydroxyethyl, benzyl or a radical of the formula -CR ⁴ = CH-CO-OR ⁵ , wherein R ⁴ represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms or a radical of the formula -CO-OR ⁵ and

R ~> represents an alkyl group having 1 to 18 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an aralkyl group having 7 to 18 carbon atoms, phenyl or tolyl, wherein:

R ^{@ 1} can also be hydrogen, C1 -C22 alkyl or C5 -C8 cycloalkyl, in amounts of up to 8 mol%, based on the remainder of formula (II);

R ² represents a mixture of alkyl groups having 14 to 28 carbon atoms, two alkyl groups, which may not differ by more than two carbon atoms each constitute at least 30% of the mixture, with an average molecular weight of from 1000 to the 50000th

Preferably, the maleic acid-α-olefin copolymers have an average molecular weight of from 1500 to 10,000, in particular from 2000 to 5000, of molecular weight.

For data on average numeric mean n

The radical R represents a mixture consisting of alkyl groups of 14 to 28 carbon atoms, preferably of alkyl groups of 16 to 24 carbon atoms, in particular of alkyl groups of 18 to 22 carbon atoms, and the 16-α-olefins are also the basis of the copolymer as building blocks. up to 30 carbon atoms, preferably α-olefins having 18 to 26 carbon atoms, in particular α-olefins having 20 to 24 carbon atoms. The radical R @ ² is preferably a straight alkyl group.

The existence of a mixture of alkyl groups for R ² to be understood that the statistical means, the total number of any molecules of the copolymer comprises two specific alkyl groups which may not differ by more than two carbon atoms, each in an amount of at least 30%, preferably each of at least 40% of this mixture. In particular, these mixtures consist of 3 certain alkyl groups, e.g. octadecyl, eicosyl and docosyl groups, two of which differ by two carbon atoms constitute more than 40% of the mixture and the third group represents 3 to 18% of the mixture, and other alkyl groups of less than 18 atoms may also be present % of the carbon or approximately having more than 22 carbon atoms in minute amounts, usually less than 2% in the mixture. _;

Alkyl radicals, which are in a form corresponding to alkyl groups having 1 to 6 carbon atoms (for R ³ and R ^4), alkyl groups having 1 to 18 carbon atoms (for ^R5) and alkyl groups having 1 to 22 carbon atoms (for R ¹ ) is preferably branched or, in particular, direct representatives, such as, in particular, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-amyl, isoamyl, sec. -amyl, t-amyl, neopentyl, n-hexyl, n-heptyl, n-octyl, 2-ethylhexyl, n-nonyl, isononyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, isotridecyl , n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, n-nonadecyl, n-eicosyl and n-docosyl.

Suitable alkanoyl group having 2 to 6 carbon atoms, Q is straight or branched chain for ^RJ , in particular acetyl, but also propionyl, butyryl, isobutyryl, pentanoyl and hexanoyl.

Suitable alkoxy groups having 1 to straight or branched chains, in particular C 6 to C 8 alkoxy groups for R ^3, are suitable carbon atoms such as hexyloxy, isohexyloxy, n-octyloxy, 2-ethylhexyloxy and isooctyloxy, but also, propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy, tert-butoxy, n-pentyloxy, n-nonyloxy, n-decyloxy, n-undecyloxy and n-dodecyloxy.

As cycloalkyloxy groups having 5 or 6 carbon atoms of R ³ are in particular cyclopentyloxy and cyclohexyloxy silyloxy group! ·

Suitable cycloalkyl radicals having 5 to 8 carbon atoms for R ¹ and R ⁵ are, in particular, cyclopentyl and cyclohexyl, but also cycloheptyl, cyclooctyl, methylcyclopentyl, dimethylcyclopentyl, methylcyclohexyl, ethylcyclohexyl _; and dimethylcyclohexyl.

As aralkyl radicals of 7 to 18 carbon atoms for R ⁵ is a suitable example. naphthylmethyl, diphenylmethyl or methylbenzyl, in particular phenylalkyl having 7 to 18 carbon atoms such as 1-phenylethyl, 2-phenylethyl, 1-phenylpropyl, 2-phenylpropyl,

3-phenylpropyl, 2-phenyl-2-propyl, 4-phenylbutyl, 2,2-dimethyl-2-phenylethyl, 5-phenylamyl, 10-phenyldecyl, 12-phenyldodecyl or especially benzyl.

Suitable tolyl radicals are ortho-, meta-and especially para-tolyl.

The radical R ^{@ 1} is preferably a tetramethylpiperidyl radical of the formula II in which R @ ³ represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, in particular methyl or a radical of the formula --CH.dbd.CH - CO - OR @ ⁶ wherein R @ ⁶ represents an alkyl group. C 1-C 6, especially methyl or ethyl.

Existence of up to 8 mol%, in particular up to 5 mol%, based on the remainder of formula II, a hydrogen atom, a C 1 -C 22 alkyl group or a C 5 -C 8 cycloalkyl group as a substituent R ¹ on the nitrogen in the acid imide anhydride is to be understood that in addition to the statistical composition of the total number of all copolymer molecules present with structural units of the formula I can be present from the mixture tetramethylpiperidyl radicals of the formula II and the other substituents R ^first The incorporation of a small amount of a residue R ¹ different from the tetramethyl 7 piperidyl substituent causes slight changes in the properties of the maleic acid and α-olefin copolymers of the present invention.

The present invention also provides a process for the preparation of maleic acid and α-olefin copolymers according to the invention, which comprises exposing maleic anhydride and α-olefin copolymers from structural units of formula III

(III) is reacted with 4-aminotetramethylpiperidine of formula IV

(IV) and optionally up to about 8 mol%, in particular up to 5 mol%, of the compound of formula IV, ammonia, up to 22 carbon atoms or 5 or 6 carbon cycloalkylamine in an organic solvent at a temperature of

Mp 100-220 ° C. Suitably, the molar ratio of anhydride groups in the compound of formula III to the primary amine of formula IV is 1: 1 or about 1: 1.

Suitable organic solvents are in particular aromatic hydrocarbons such as toluene, xylene or mesitylene and halogenated or nitrated hydrocarbons such as chlorobenzene, dichlorobenzene or nitrobenzene. Of particular importance are technical mixtures of such aromatic compounds. In addition, however, mixtures of non-aromatic hydrocarbons are also useful as long as they have a correspondingly high boiling range.

s

The reaction temperature should preferably be in the range of from 120 to 200 ° C, in particular from 140 to 175 ° C. The water formed in the reaction is conveniently removed by azeotropic distillation. The reaction is usually carried out at normal pressure and is generally complete after 1 to 5 hours.

The copolymers of maleic anhydride and α-olefin used as starting material, with structural units of formula III, can be obtained according to a known production process by polymerizing maleic anhydride with a corresponding mixture of α-olefins, e.g. according to the data of Houben-Weyl, Methoden der organischen Chemie, Vol. E20 / 2, p. 1237-1248 (1987).

Both the maleic acid and α-olefin copolymers of the present invention, with structural units of formula I, and the copolymers of maleic anhydride and α-olefin used as starting material, with structural units of formula III, are generally copolymers in a 1: 1 ratio , exposed from alternating units of maleic acid derivative and olefin.

The maleic acid-α-olefin copolymers of the present invention are useful in an excellent way to stabilize organic material against light, oxygen and heat. These copolymers are used to stabilize organic materials at a concentration of from 0.01 to 5% by weight, preferably from 0.02 to 1% by weight, based on the organic material, before, during or after its production.

Organic material is understood to be e.g. cosmetic preparations such as pill and suppository ointments, photographic emulsions or lotions, medical preparations such as photographic recording material, or precursors for plastics and lacquers, in particular plastics and lacquers themselves.

The present invention furthermore comprises an organic material, in particular a plastic and a lacquer, stabilized against the effects of light, oxygen and heat, comprising the copolymer according to the invention in the concentration mentioned above.

For the mixing of the copolymer according to the invention, in particular with plastics, all known devices and methods for mixing the stabilizing agents or other additives into the polymer can be used.

The organic material stabilized by the copolymer of the invention may optionally contain still further additives, e.g. antioxidants, other light stabilizers, metal deactivators, antistatic agents, flame retardants, pigments and fillers.

Antioxidants and light stabilizers that may be added in addition to the copolymers of the present invention are e.g. compounds based on spherically hindered phenols or co-stabilizers containing sulfur or phosphorus.

As such phenolic antioxidants, e.g. mention 2,6-di-tert-butyl-4-methylphenol, n-octadedyl-β- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 1,1,3-tris- (2 -methyl-4-hydroxy-5-tert-butylphenyl) butane, 1,3,5-trimethyl-2,4,6-tris- (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, 1,3,5-tris- (3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate, 1,3,5-tris- p - (3,5-di-tert-butyl-4) -hydroxyphenyl) propionylethyl / isocyanurate, 1,3,5-tris- (2,6-dimethyl-3-hydroxy-4-tert-butylbenzyl) isocyanurate and pentaerythritol-tetrakis / p- (3,5-di-tert-butyl) .-butyl-4-hydroxyphenyl) propionate /.

As phosphorus-containing antioxidants, e.g. consider tris (nonylphenyl) phosphite, distearylpentaerythritol diphosphite, tris- (2,4-di-tert-butylphenyl) phosphite, tris- (2-tert-butyl-4-methylphenyl) phosphite, bis- (2,4 di-tert-butylphenyl) pentaerythritol diphosphite and tetrakis (2,4-di-tert-butylphenyl) -4,4'-biphenylenediphosphite.

As sulfur-containing antioxidants, e.g. they are called dilauryl thiodipropionate, dimyristyl thiodipropionate, distearyl thiodipropionate, pentaerotetretretris (β-laurylthiopropionate) and pentaerotetretretris (β-hexylthiopropionate).

Other antioxidants and heat stabilizers that can be used together with the copolymers of the present invention are e.g. 2- (2'-hydroxyphenyl) -benzotriazole, 2-hydroxybenzophenone, arylesters of hydroxybenzenoic acid, α-cyanocinnamic acid derivatives, benzimidazolecarboxylic acid anilide, nickel compounds or oxalic acid anilides.

Industrial usability

As plastics which can be stabilized by the copolymers according to the invention, e.g. call:

polymers of monoolefins and diolefins, such as e.g. low or high density polyethylene, polypropylene, linear poly-1-butene, polyisoprene, polybutadiene, also as copolymers of monoolefins or diolefins or mixtures of said polymers, copolymers of monoolefins or vinyl monomers, such as e.g. with an alkyl acrylate, a copolymer of ethylene diolefins with other copolymers of ethylene with alkyl methacrylate, copolymers of ethylene with vinyl acetate or copolymers of ethylene with acrylic acid, polystyrene, also as copolymers of styrene or α-methylstyrene with dienes and / or acrylic derivatives. styrene-butadiene, styrene-acrylonitrile (SAN), styrene-ethyl methacrylate, styrene-butadiene-ethyl acrylate, styrene-acrylonitrile-methacrylate, acrylonitrile-butadiene-styrene (ABS) or methylmethacrylate-butadiene-styrene (MBS), polymer, e.g. polyvinyl chloride, polyvinylfluoride, polyvinylidene fluoride, also as copolymers thereof, polymers derived from α, β-unsaturated acids and their derivatives, such as polyacrylates, polymethacrylates, polyacrylamides and polyacrylonitriles, polymers derived from their unsaturated or unsaturated acids and their unsaturates derivatives or acetals, e.g. polyvinyl alcohol or polyvinyl acetate, polyurethanes, polyamides, polyureas, polyesters, polycarbonates, polysulfones, polyether sulfones and polyether ketones.

With the copolymers of the present invention, lacquer coatings, e.g. for industrial painting. Of these, baking varnishes are particularly preferred, among which vehicle paints, preferably two-layer paints, are again preferred. Another field of application is e.g. coating compositions for exterior painting of buildings, other structures or technical installations.

The copolymers of the invention may be added in solid or dissolved form to the lacquers. Their good solubility in paint systems is particularly advantageous.

The copolymers according to the invention are preferably suitable for stabilizing polyamides, also as copolymers of acrylonitrile, butadiene and styrene (ABS) and styrene-acrylonitrile (SAN) copolymers, among them in particular molding compositions and lacquers.

Another preferred field of their use is to stabilize low or high density polyethylene, as well as polypropylene and polyamide, e.g. or fibers made from them.

The copolymers according to the invention are suitable, by virtue of their stability against migration, in particular for the stabilization of articles with a high surface area by volume volume, in particular also of films, bundles and fibers.

The copolymers of the solubility tolerances of the present invention are characterized by good with the usual kinds of plastics, good and excellent compatibility in conventional paint systems. As a rule, these copolymers have no intrinsic coloration, or this coloration is only slight, stable at the usual processing temperatures for plastics and varnishes, non-volatile, and long-term protection of the material treated with them.

Surprisingly, the copolymer of maleic acid imide and α-olefin according to the present invention, with a mixture of C 18 -C 22 alkyl groups as the residue R ² (see example), as compared to an analogous maleic acid imide α-olefin copolymer known from patent identified above document (2), the alkyl group having 16 carbon atoms as the radical R ² (see comparative example A) has distinct advantages in efficacy is documented by comparison of said two polypropylene copolymers to the spray casting.

DETAILED DESCRIPTION OF THE INVENTION

Example

To a solution of 203 g of a 1: 1 copolymer, with alternating residues of maleic anhydride and a-olefin mixture, composed of

1-octadecene 1 % materials. 1-eicosene 49 % materials. 1-docosene 42 % materials. 1-tetracosene 8 % materials. 1-hexacosene <0.1 % materials.

in 400 ml of a commercially available aromatic hydrocarbon mixture, boiling in the range of 160-170 [deg.] C., 117 g of 4-amino-2,2,6,6-tetramethylpiperidine are added dropwise over 20 minutes. The reaction mixture is then heated to reflux for 180 minutes at this temperature. Thereafter, no more water is separated in the water separator, the solvent is distilled off under reduced pressure. The solid melt is ground to give 250 g of N- (2,2,6,6-tetramethyl-4-piperidyl) maleic acid imide copolymer and α-olefins of 20 to 24 carbon atoms as a light yellow powder, m.p. Mp 104-111 ° C.

Comparative example

Analogously to the example described above, N- (2,2,6,6-tetramethyl-4-piperidyl) maleic acid copolymer is produced from a copolymer in a ratio of 1: 1, with alternating residues of maleic anhydride and 1-octadecene, and 1-octadecene having a melting point of 60-69 ° C.

Technical use of properties

Process for producing polypropylene test specimens

0.5% by weight. of the stabilizer of Example A or Comparative Example A is dissolved in Novolen ^R 1100 C polypropylene once extruded at 240 ° C, measured from the polymer, and the resulting granulate is sprayed onto 2 mm test specimens at 240 ° C.

The test specimens are tested in a Xenotest 1200 rapid> R »weather and weather resistant device. The measure for photooxidative 'polymer degradation' is the surface quality of the test pieces,. depending on the weather. Thus, the time to the first crack formation is determined.

Test specimens containing the prior art stabilizer of Comparative Example A exhibit cracks as early as 2500 hours. However, the test bodies which contain the stabilizer according to the invention described in the example do not occur until at least 3000 hours.

WO-9 / -

Claims (10)

An imide copolymer of the structural acids of maleic and α-olefin units exhibited by the general formula I (I) in which: R ⁴ represents a tetramethylpiperidyl radical of formula (II ^); x Wherein R represents a hydrogen atom, an alkyl group X is C 1 -C 6, formyl, C 2 -C 6 alkanoyl, C 1 -C 12 alkoxy, C 5 -C 6 cycloalkyloxy, cyanomethyl, 2-hydroxyethyl, benzyl or the radical -CR ⁴ = CH-CO-OR ⁵ wherein R ⁴ represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms or a radical of the formula -CO-OR ⁵ and R ⁵ represents an alkyl group having 1 to 18 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an aralkyl group having 7 to 18 carbon atoms, phenyl or tolyl, wherein: In an amount of up to 8 mol%, based on the remainder of formula (II), R ^{@ 1} may also be: a hydrogen atom, an alkyl group having 1 to 22 carbon atoms or a cycloalkyl group having 5 to 8 carbon atoms, and R ² represents a mixture of alkyl groups having 14 to 28 carbon atoms, two alkyl groups, which may not differ by more than two carbon atoms each constitute at least 30% of the mixture, with an average molecular weight of from 1000 to the 50000th 2. Maleic acid-α-olefin copolymer according to n The composition of claim 1, wherein the radical R represents a mixture consisting of alkyl groups having 16 to 24 carbon atoms and comprising two of these alkyl groups which cannot differ by more than two carbon atoms, in each case in an amount of at least 40% of the mixture. The maleic acid-α-olefin copolymer of claim 1 or 2, wherein R ¹ is tetramethylpiperidyl q a radical of formula (II) in which R is a hydrogen atom, a (C1-C6) alkyl group or a radical of the formula -CH = CH-CO-OR4, wherein R6 is a (C1-C6) alkyl group. A process for the preparation of a maleic acid-α-olefin copolymer according to claims 1 to 3, characterized in that the maleic anhydride-α-olefin copolymer exposed from the structural units of the general formula III (III) is reacted with 4- aminotetramethylpiperidine of the formula IV (IV) and optionally up to 8 mol%, based on the compound of the formula IV, ammonia, C 1 -C 22 alkylamine or C 5 or C 6 cycloalkylamine in an organic solvent at a temperature of from 100 to 220 ° C. Light, oxygen and heat stabilized organic material, characterized in that it contains from 0.01 to 5% by weight, based on the amount of organic material, of one or more of the maleic acid and α-olefin copolymers according to claims 1 to 5 third 6. Light, oxygen and heat-stabilized plastics and varnishes, characterized in that they contain from 0.01 to 5% by weight, based on the amount of plastic or lacquer, of one or more maleic acid-α-olefin copolymers according to claims 1 to 3. 7. Use of maleic acid copolymers; and α-olefin according to claims 1 to 3 as a light protection agent and a stabilizer for organic material. it Use of the maleic acid-α-olefin copolymers according to claims 1 to 3 as a light protection agent and a stabilizer for plastics and lacquers. Method for stabilizing the organic material against the action of light, oxygen and heat, characterized in that the copolymers of maleic acid and α-olefin according to claims 1 to 3 are subsequently used. Method for stabilizing plastics and varnishes against light, oxygen and heat, characterized in that the copolymers of maleic acid and α-olefin according to claims 1 to 3 are subsequently used.