DE2309376A1 - 4-(m,m'-di tert butyl-p-hydroxy phenyl)-butyl-2-cpds. - used as starting matls. for plastics, etc. - Google Patents

Abstract

New cpds. (I) are of formulae XOOCR3, XNHCOR3, XNHCONHR4NHCONHX and XNHCO-(R5)n-CONHX, (where gp. X is of formula (II) and R1 are H (pref.) or aliphatic gps; R3-5 are aliphatic, cycloaliphatic, arylaliphatic or aromatic gps; and n = 0 or 1). (I) esters are prepd. by reacting the alcohol XOH with the carboxylic acid R3COOH or the corresponding acid halide or anhydride at 10-170 degrees C, pref. 20-90 degrees C. The amide, bisamide or bisurea is formed by reacting the amine XNH2 with derivs of the carboxylic acids R3COOH or HOOC-(R5)n COOH, or with the bi-isocyanate OCN-R4-NCO respectively. The cpds. are used as starting materials for dyestuffs, pesticides, plastics and perfume compsns. or as stabilizers or antioxidants for organic materials, e.g. polymers.

Description

4- (m, m 'di-tert-butyl-p-hydroxyphenyl) butyl (2) compounds The invention relates to the new 4- (m, m'-di-tert-butyl-hydroxyphenyl) butyl (2) compounds.

There were the new 4- (m, m'-di-tert-butyl-p-hydroxyphenyl) butyl (2) compounds of the formula in which the individual radicals R1 can be identical or different and each represent a hydrogen atom or an aliphatic radical and R2 represents the radical where R1 has the aforementioned meaning and R3, R4 and R5 each denote an aliphatic, cycloaliphatic, araliphatic, aromatic radical and n denotes the number 0 or 1.

Preferred end products are the new 4- (m, m'-di-tert-butyl-hydroxyphenyl) butyl (2) compounds of the formula where R2 is the remainder or or in which R3, R4 and R5 each denote an aliphatic, cycloaliphatic, araliphatic, aromatic radical and n denotes the number 0 or 1.

The new substances can be prepared by the usual methods of synthesis of esters, acid amides, bisureas and bisamides. For the preparation of the esters of the formula it is advantageous to use 4- (m, m'-di-tert-butyl-p-hydroxyphenyl) -butane-2 ° ols of the formula and carboxylic acids or derivatives of carboxylic acids of the formula wherein R1 and R5 have the aforementioned meaning to. The starting materials IV can be prepared according to known methods, advantageously according to the patent. ... ... (patent application P OZ29 725) described process can be produced by reducing the corresponding butanones.

In the case of using 4- (m, m'-di-tert-butyl-p-hydroxyphenyl) -butan-2-ol and acetic acid chloride, the reaction can be represented by the following formulas: Preferred starting materials IV, V and correspondingly preferred end materials III are those in whose formulas the individual radicals R1 can be identical or different and each represent an alkyl radical with 1 to 4 carbon atoms or, in particular, a hydrogen atom, and R5 is an alkyl radical with 1 to 20, in particular 1 up to 6 carbon atoms, a cyclohexyl radical, an aralkyl radical with 7 to 12 carbon atoms, a naphthyl or phenyl radical. The abovementioned radicals can also be replaced by groups which are inert under the reaction conditions, for example

Alkyl groups, alkoxy groups each with 1 to 4 carbon atoms, Nitro groups, may be substituted. A particularly advantageous starting material IV is 4- (m, m'-Di-tert-butyl-p-hydroxyphenyl) -butan-2-ol. Further starting materials are IV for example 4-methyl-, 3-ethyl-, l-ethyl-, 1,4-dimethyl-, 1,3,4-trimethyl-4- (m, m'-di-tert-butyl-p-hydroxyphenyl) -butan-2-ol.

The starting materials V are carboxylic acids and derivatives of carboxylic acids such as the halides, preferably chlorides, and simple or mixed anhydrides into consideration. For example, are suitable formic acid, acetic acid, Butyric acid, palmitic acid, stearic acid, benzoic acid, cyclohexanecarboxylic acid, phenylacetic acid, Naphthalene-1-carboxylic acid, naphthalene-2-carboxylic acid, p-nitrobenzoic acid, p-hydroxy-m, m '-di-tert. -butylbenzoic acid, p-toluic acid, propionic acid, isobutyric acid, caprylic acid, Caproic acid, lauric acid, valeric acid, (p-methoxy-m, m'-di-tert-butyl) benzoic acid, o- or p-diethoxybenzoic acid; analogous acid halides and anhydrides.

You can use the starting material IV with the starting material V in stoichiometric Amount or in excess, preferably in an amount of 1.1 to 1.5 mol of starting material V convert per mole of starting material no. The reaction will usually take place at one temperature between 10 and + 1700C, 'preferably between 20 and + 90 ° C, without pressure or below Pressure, carried out continuously or discontinuously. Used appropriately solvents such as ketones, e.g. acetone; aliphatic hydrocarbons, e.g. Ligroin, hexane; Ethers such as dipropyl ether, tetrahydrofuran, dioxane; aromatic hydrocarbons, e.g., benzene, toluene, xylenes; Chlorinated hydrocarbons, e.g. chloroform, methylene chloride.

In the case of carboxylic acids as starting materials V are expedient Acids such as phosphoric acid, aromatic sulfonic acids such as p-toluenesulfonic acid or expediently added hydrogen chloride and sulfuric acid as catalysts; advantageous are in particular 0.5 to 15, in particular 3 to 10% by weight of acid, based on carboxylic acid V. If necessary, substances that bind the water formed can also be used, e.g. anhydrous salts such as copper sulphate, iron sulphate. Esterification catalysts are also used such as acid chlorides, e.g. thionyl chloride, chlorosulfonic acid, ansolvo acids such as boron trifluoride, or special esterification operations, e.g. esterification with azeotropic distillation with e.g. benzene or toluene.

It is also possible to use esters of the carboxylic acids V, advantageously with lower alkanols such as methanol or ethanol to transesterify with the starting material IV. It is useful to work with one Excess, e.g. 3 to 10 times Excess of starting material IV, based on the stoichiometric amount of ester, and with simultaneous distillation of the alkanol split off in the reaction. Preference is given to using halides of the carboxylic acids V, in particular the chlorides, as starting materials; they can optionally by using the carboxylic acids V and acid chlorides such as phosphorus trichloride, phosphorus oxychloride, phosphorus pentachloride, Thionyl chloride, are only formed in the reaction mixture. Implementation is preferred the starting materials IV with the acid anhydride or, expediently, acid halide in the presence of pyridine, with amounts of 200 to 1,000% by weight of pyridine, based on acid halide, come into question; if appropriate, the halide can also be used in this procedure are only formed in a mixture of acid and e.g. phosgene. The amounts of anhydride, Halide and the reaction conditions correspond to the aforementioned conditions when using carboxylic acids. Regarding the details of the esterification reaction reference is made to Houben-Weyl, Methods of Organic Chemistry, Volume 8, pages 516-549.

The reaction can be carried out as follows: A mixture of the Starting materials IV and V or of derivatives of the starting materials V and optionally Solvent, esterification catalyst, acid or pyridine, is used in the aforementioned Maintained temperature with stirring for 1 to 12 hours. Now the ester III in the usual way, e.g. by mixing with ice, acidifying and extracting the mixture with e.g. benzene and fractional distillation of the organic phase formed, isolated.

For the preparation of the acid amides of the formula and the bisamides of the formula it is advantageous to use 2-amino-4- (m, m'-di-tert-butyl-hydroxyphenyl) -butanes of the formula in the case of the preparation of acid amides VI the aforementioned carboxylic acids V or derivatives of carboxylic acids V and in the case of the preparation of bisamides VII dicarboxylic acids or derivatives of dicarboxylic acids of the formula wherein R1, R3, R5 and n have the aforementioned meaning.

If 2-amino-4- (m, m'-di-tert-butyl-p-hydroxyphenyl) butane and benzoyl chloride or terephthalic acid dichloride are used, the reactions can be represented by the following formulas: The starting amines VIII are prepared by customary methods, advantageously according to that described in the patent. ... ... (patent application P-OZ29 726) described process by reductive amination of corresponding 4- (m, m'-di-tert-butyl-p-hydroxyphenyl) -butan-2-one. Preferred starting materials VIII, V and IX and correspondingly preferred end materials VI and VII are those in whose formulas R1 and R3 have the aforementioned preferred meaning, n is the number 0 or 1 and R5 is an alkylene radical with 1 to 20, in particular 1 to 6 Carbon atoms, a cyclohexylene radical, an aralkylene radical with 7 to 15 carbon atoms, a phenylene radical or an optionally wholly or partially hydrogenated naphthylene radical, a benzylcyclohexylene radical, for example the radical or a benzylphenylene radical, for example the radical means. The abovementioned radicals can also be substituted by groups which are inert under the reaction conditions, for example alkyl groups, alkoxy groups each having 1 to 4 carbon atoms. R5 in its meaning as an aralkylene radical can contain an arylene group and one or 2 alkylene groups and thus be connected to the two adjacent carbonyl groups via an arylene group and an alkylene group or via 2 alkylene groups.

A particularly advantageous starting material VIII is 2-amino-4- (m, m ' -di-tert-butyl-p-hydroxyphenyl) butane. Further starting materials VIII are for example 4-methyl-, 3-ethyl-, l-ethyl-, 1,4-dimethyl-, 1,3,4-trimethyl-2-amino-4- (m, mt-di-tert-butylp-hydroxyphenyl) -butane. The aforementioned monocarboxylic acids V and their derivatives are used as starting materials such as halides, especially chlorides, and anhydrides in question. As starting materials IX are for example oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, Pimelic acid, sebacic acid, decanedicarboxylic acid, terephthalic acid, cyclohexane-1,4-dicarboxylic acid, Cyclohexane-1,2- or 1,3-dicarboxylic acid, naphthalene-1,4-dicarboxylic acid, naphthalene-1,8-dicarboxylic acid, Isophthalic acid, phthalic acid, diphenylmethane-4,4'-dicarboxylic acid, 4- (p-carboxybenzyl) -cyclohexanecarboxylic acid, Tetrahydronaphthalene-1,8-dicarboxylic acid, Tetrahydronaphthalene-1,5-dicarboxylic acid, Decahydronaphthalene-1,8-dicarboxylic acid, decahydronaphthalene-1,5-dicarboxylic acid, p- (l-carboxypropyl- (2) -) benzoic acid, p- (carboxymethyl) -benzoic acid, p- (carboxymethyl) -phenylacetic acid, suitable; corresponding Analog simple or mixed anhydrides and dihalides, preferably Dichlorides, of these acids.

You can start material VIII with the starting material V or IX in stoichiometric Amount or in excess, preferably in a ratio of 1.1 to 1.3 mol of starting material V or from 0.6 to 0.8 moles of starting material IX per mole of starting material VIII. The reaction is usually carried out at a temperature between 10 and + 170 ° C, preferably between 20 and + 90 ° C, without pressure or under pressure, continuously or discontinuously carried out. It is expedient to use solvents such as ketones, e.g. acetone; aliphatic Hydrocarbons, e.g., ligroin, hexane; Ethers such as dipropylethetetrahydrofuran, Dioxane; aromatic hydrocarbons such as benzene, toluene, xylenes; Chlorinated hydrocarbons, e.g. chloroform, methylene chloride.

As in the case of the esters, the amines VIII can be mixed with the monocarboxylic acid Implement V or dicarboxylic acid IX itself or its esters. The advantage becomes harder Reaction with the anhydrides and especially the halides, preferably the chlorides, these acids carried out. The acid formed in the reaction can by a appropriate excess of amine or expediently by adding bases such as alkaline solutions, e.g.

Sodium hydroxide, soda or tertiary amines, especially pyridine, bound will; there are amounts of 1 to 1.5 equivalents of base, based on one mole of halide or anhydride of acids IX, into consideration. You can also use pyridine at the same time Use solvents, amounts of 1 to 1.3 moles of pyridine per mole of starting material VIII come into consideration. Regarding details of the preparation of mono- and di-carboxamides is on Houben-Weyl, loc. cit., pages 653-660.

The reaction can be carried out as follows: A mixture of starting material VIII and the acid chloride of the starting material V or IX and expediently the base and optionally the solvent is left for 0.5 to 5 hours at the reaction temperature held. The end product is then removed from the reaction mixture in a conventional manner, e.g. by mixing with ice, acidifying the mixture, extracting with e.g. benzene and fractional distillation of the extract, separated.

For making the bisureas of the formula it is advantageous to use 2-amino-4- (m, m'-di-tert-butyl-hydroxyphenyl) -butane VIII and diisocyanates of the formula OCN-R4-NCO XI, in which R1 and R4 are as defined above.

If 2-amino-4- (m, m'-di-tert-butyl-hydroxyphenyl) butane and hexamethylene diisocyanate are used, the reaction can be represented by the following formulas: Preferred starting materials VIII, XI and correspondingly preferred end materials X are those in whose formulas R1 has the aforementioned preferred meaning and R4 has the aforementioned preferred meaning of R5, it being possible for the preferred radicals to be substituted in the manner indicated. 2-Amino-4- (m, m'-di-tert-butyl-hydroxyphenyl) -butane is also a particularly advantageous starting material VIII in the production of the end products X, and the other individual substances VIII already mentioned can also be used for this reaction be used. As starting materials XI, for example, 1,4-butane, 1,6-hexane, p-phenylene, 2,4-tolylene, 2,5-tolylene, 2,6-tolylene, 1,5- or 1,8-naphthylene, 4,4-diphenylmethane, 3,3'-dimethoxy-4,4'-diphenyl-, 3,3'-dimethyl-4,4'-diphenyl-, 1,3-propane , 1,3- or 1,4-cyclohexylene, m-phenylene, tetrahydronaphthalene-1,5 (or -1.8) -, decahydronaphthalene-1,5 (or -1.8) diisocyanate, 4- ( Isocyanatobenzyl) cyclohexane isocyanate, p-isocyanato-cumyl isocyanate, p-isocyanato-benzyl isocyanate, p-isocyanato-phenylethyl isocyanate are suitable.

You can use the starting material VIII with the starting material XI in stoichiometric Amount or in excess, preferably in an amount of 0.6 to 0.8 mol of starting material XI per mole of starting material VIII. The response is usually at one Temperature between 10 and + 170 ° C, preferably between 20 and + 90 ° C, without pressure or carried out under pressure, continuously or batchwise. Appropriate one uses solvents such as ketones, e.g. acetone; aliphatic hydrocarbons, e.g.

Ligroin, hexane; Ethers such as dipropyl ether, tetrahydrofuran, dioxane; aromatic hydrocarbons such as benzene, toluene, xylenes; Chlorinated hydrocarbons, e.g. chloroform, methylene chloride.

As in the case of the production of the end products VI and VII can also in the preparation of the bisureas bases, preferably pyridine, in the specified Way to be added. Regarding the details of the implementation of amines with Diisocyanates is referred to Houben-Weyl, loc. cit., pages 157 ff., referenced.

The reaction can be carried out as follows: A mixture of the Starting materials and optionally solvent and base is used for 0.5 to 5 Held at the reaction temperature for hours. Then from the reaction mixture the end product in the usual way, e.g. by filtration or removal of the solvent and recrystallization of the residue, separated.

The 4- (m, m'-di-tert-butyl-hydroxyphenyl) butyl (2) compounds which can be prepared in the aforementioned manner I, in particular the mono- or dicarboxamides, esters or bisureas of 2-amino-4- (m, m'-di-tert-butyl-p-hydroxyphenyl) -butane, are valuable starting materials for the production of dyes and pesticides and plastic auxiliaries, especially stabilizers for polyolefins and polyamides. In the form of their melts, they are specific solvents for alkylphenols, e.g. 2,6-diethylphenol, 2,6-dimethylphenol, 2,4-dimethylphenol, or of disubstituted ones Urea, e.g. diphenylurea, and fragrances or components of fragrance mixtures with a specific fruity smell.

Substances I themselves are also stabilizers and anti-aging agents or antioxidants for organic products that by the action deformed, embrittled, discolored or damaged by heat, light, oxygen or ozone to be decomposed in another way; such organic products are e.g. lubricating oils, Heating oils, lead mineral, vegetable or animal origin, waxes, soaps, Fats, petrol, natural and synthetic rubber, natural resins and plastics such as polyolefins, e.g.

Polyethylene and polypropylene, and polyamides.

In this context, advantageous substances I are 4- (m, m'-di-tert-butyl-p-hydroxyphenyl) butyl (2) compounds of the formula where R2 is the remainder or or in which R3, R4 and R5 each denote an aliphatic, cycloaliphatic, araliphatic, aromatic radical and n denotes the number 0 or 1. Substances I are particularly preferred, in the formulas of which R2 and n have the aforementioned meaning and R3, R4 and R5 have the aforementioned preferred meaning.

Particularly advantageous end products I are, for example, the following individual substances: For example, the acid amides VI are used as stabilizers for polyolefins in amounts of 0.05 to 0.2% by weight, based on the total weight (see also Example 9). Regarding the use for polyolefins is also on patent.

(Patent application P - O.Z. 29 723) referenced.

In the case of the stabilization of polyamides, amounts from 0.01 to 2 wt. Substance I, based on the polymer, in question.

The addition can be added to the starting monomers of the prior to the polymerization Polyamide done, it can be made during the polymerization and he can be done by assembling it into the finished polyamide. The stabilizing Effect extends to all polyamides and copolyamides as well as polyamide blends from the well-known polyamide-forming compounds such as lactams, Diamines and dicarboxylic acids and aminocarboxylic acids. As polyamide-forming lactams, e.g. Pyrrolidone, caprolactam, caprylic lactam, oenantlactam, aminoundecane lactam and laurolactam to mention, which polymerizes according to the cationic mechanism alone or in a mixture can be. Polycondensates from diamines and dicarboxylic acids are e.g. those from aliphatic dicarboxylic acids with 4 to 18 carbon atoms and diamines with 4 to 18 carbon atoms producible, in particular polyamide 6,6 and 6,10. Uncolored polyamides are obtained which even under high stress from heat and oxidizing influences in their Properties one compared to the conventional phenolic stabilizers have greatly improved stability. The stabilization is suitable for both Polyamides that are used for the production of moldings as well as those that are used for the manufacture of fibers and threads are provided. The is particularly suitable Use of the stabilizers according to the invention for colored polyamides, since their Color values are not affected. This is especially true for pigments. About that In addition, the polyamides can use conventional fillers, e.g. glass fibers, others without disadvantage Polymers, lubricants, crystallization accelerators, and other conventional additives as well as other additional stabilizers. Regarding the use will also on patent. ... ... (Patent application P - O.Z. 29 724 referenced.

The parts listed in the following examples are parts by weight. They relate to parts by volume like the kilogram to the liter.

Example 1 To 35 parts of 4- (m, m'-di-tert-butyl-p-hydroxyphenyl) butane (2) -ol and 100 parts by volume of pyridine are 42.5 parts of palmitic acid chloride 250C slowly added. The mixture is kept at this temperature for a further 3 hours. Then the mixture is poured onto ice, acidified with 40 parts of HC1 and with 200 Part of benzene extracted. The benzene is then distilled off from the extract and the residue is distilled in vacuo. 55 parts (84.5% of theory) of 4- (m, m'-di-tert-butyl-p-hydroxyphenyl) butyl-2-ester are obtained of palmitic acid from Kg, 01 2540C.

Example 2 To 111 parts of 2-amino-4- (m, m '-di-tert-butyl-p-hydroxyphenyl) -butane and 300 parts by volume of pyridine, 124 parts of palmitic acid chloride are obtained at 20 to 25 ° C slowly admitted. The mixture is kept at this temperature for a further 2 hours. then the mixture is poured onto 1,000 parts of ice and acidified with 100 parts of hydrochloric acid and extracted with 500 parts of benzene extract. The benzene is distilled off from the extract and the residue is distilled in vacuo. 143 parts are obtained (69.5% of theory) Palmlatinic acid 4- (m, m'-di-tert-butyl-p-hydroxyphenyl) -butyl- (2) -amide of Kg 0.01 252 ° C.

Example 3 To 42 parts of 2-amino-4- (m, m'-di-tert-butyl-p-hydroxyphenyl) butane, 500 parts by volume of benzene and 20 parts of sodium carbonate become 21 parts of benzoyl chloride and 100 parts by volume of benzene were added over 80 minutes at 5 to 10 ° C. One holds the mixture for 45 minutes at this temperature sets 20 parts of sodium carbonate to, the mixture is kept at 100 ° C. for 3 hours and then under reflux for 2 hours. The mixture is filtered off while hot, the filtrate is concentrated, and on cooling the crystalline Separates end product. 54 parts (93.5% of theory) of benzoic acid 4- (m, m'-di-tert-butyl-p-hydroxyphenyl) butyl (2) amide are obtained of m.p. 140 to 1410C.

Example 4 To 83 parts of 2-amino-4- (m, m'-di-tert-butyl-p-hydroxyphenyl) butane and 300 parts by volume of pyridine become 30 parts of terephthalic acid dichloride and 80 parts by volume Benzene was added at 25 ° C. in 90 minutes. The mixture is kept there for 2 hours Temperature.

The mixture is then poured onto 300 parts of ice. Now the mixture is acidified with 40 parts of hydrochloric acid and extracted with 500 parts of benzene. From the Extract, the benzene is distilled off, the crystalline end product separating out. 65 parts (6), 5% of theory) of terephthalic acid di- [4- (m, m'-di-tert-butyl-p-hydroxyphenyl) butyl (2) amide] are obtained with m.p. (benzene / methanol 1: 1) 245 to 247 ° C.

Example 5 To 111 parts of 2-amino-4- (m, m '-di-tert-butyl-p-hydroxyphenyl ) -butane, 500 parts by volume of benzene and 2 parts by volume of pyridine are 55 parts of diphenylmethane-4,4'-diisocyanate slowly added in 500 parts by volume of chloroform at 25 to 300C. The mixture will then heated to 40 ° C. for one hour and then filtered off with suction. 77 parts are obtained (48% of theory) 4,4'-di-24 "'- (m, m'-di-tert-butyl-p-hydroxyphenyl) -butyl- (2"') - ureido] -diphenylmethane with m.p. (benzene / methanol 1: 1) 183 to 186 ° C.

Example 6 To 107 parts of 2-amino-4- (m, m '-di-tert-butyl-p-hydroxyphenyl ) butane, 500 parts by volume of benzene and 2 parts by volume of pyridine become 37 parts of hexamethylene diisocyanate added at 250 ° C.

The mixture is kept at 60 ° C. for 15 hours. Then the mixture sucked off. 110 parts (78.5% of theory) of c (>, W '-Di- E- -Di-r- (m, m' -di-tert. -butyl-p-hydroxyphenyl) -butyl- (ureidohexane from melting point (benzene / methanol 1: 1) 200 Example 7 To 44 parts of 2-amino-4- (m, m'-di-tert-butyl-p-hydroxyphenyl) butane, 150 parts by volume of benzene and 0.2 parts by volume of pyridine are 16 parts of p-isocyanato-cumyl isocyanate added at 20 to 250 C in 15 minutes. The mixture is refluxed for 10 minutes heated and then the benzene is distilled off. The residue is mixed with 200 parts of cyclohexane heated to 700C and sucked off.

57 parts (94% of theory) Np- [4- (m, m'-di-tert-butyl-p-hydroxyphenyl) -butyl- (2) -ureido-isopropyg-phenyl- (m, m '-di-tert.utyphydroxypheny1J) -butyl- (2) -urea.

from m.p. 40 to 450C.

Example 8 To 28 parts of 2-amino-4- (m, m'-di-tert-butyl-p-hydroxyphenyl) butane, 100 parts by volume of benzene and 0.2 parts by volume of pyridine become 12 parts of decahydronaphthalene-1,5-diisocyanate added at 250C for 30 minutes. The mixture is refluxed for 15 minutes and the benzene is distilled off. 30 parts (79.5 ffi of theory) of 1,5-di- [4- (m, m'-di-tert-butylp-hydroxyphenyl) -butyl- (2) -ureido are obtained - decahydronaphthalene from m.p. 40 to 450C.

Example 9 Polypropylene is made with 0.2% by weight of the palmitic acid amide of 4- (m, m'-di-tert-butyl-p-hydroxyphenyl) -2-aminobutane, based on the total weight, mixed and melted. The stabilized polypropylene is then 1 mm thick Sheets rolled out 'from which sheets cut out with a size of 15 x 40 x 1 mm will. The platelets are hung in a thermal chamber through which they are constantly involved 1400C air is passed through. For comparison, platelets of the same size are unstabilized Added polypropylene. The platelets are made by a mechanical device constantly moving. In this aging test, the decomposition of the polypropylene is reduced checked under more stringent conditions. In contrast to the unstabilized polypropyte platelets, which show signs of decomposition after just a few hours in the case of the stabilized polypropylene platelets, there was still no oxidative effect after 450 hours Decomposition and discoloration noted.

Claims (1)

Claims m> m1 4- (m, m'-di-tert-butyl-p-hydroxyphenyl) butanyl (2) compounds of the formula in which the individual radicals R1 can be identical or different and each represent a hydrogen atom or an aliphatic radical and R2 represents the radical where R1 has the abovementioned meaning and R3> R4 and R5 each denote an aliphatic, cycloaliphatic, araliphatic, aromatic radical and n denotes the number 0 or 1. 2,4 (m, m'-di-tert-butyl-p-hydroxyphenyl) butanyl (2) compounds of the formula where R2 is the remainder in which R3, R4 and R5 each denote an aliphatic, cycloaliphatic, araliphatic, aromatic radical and n denotes the number 0 or 1.