Antioxidant mixture comprising at least one compound of the formula in which R is CH 2 -CH(R I), CH(R II)-CH(R II), CH 2 -C(R II) 2, C(R II) 2 -C(R II) 2, CH 2 -CH-CH 2 -R IV, C 6 H 6 -CH-CH 2, or C 6 H 6 -C(CH 3)-CH 2, where R I is C 2 to C 24 alkyl radical or alkene radical, which may be linear or branched R II is C 2 to C 24 alkyl radical or alkene radical, which may be linear or branched R III is C 3 to C 6 alkyl radical, which is arranged linearly, and R IV is OH, Cl, OCH 3, OCH 2 -CH 3, O-CH 2 -CH=CH 2, O-CH=CH 2, molecule residue of singly or multiply epoxidized fats or oils as mono-, di-, and triglycerides, or molecule residue of singly or multiply epoxidized fatty acids or their C 1 -C 24 alkyl esters, R 1 and R 2 independently of one another are straight-chain or branched C 1 -C 8 alkyl, cyclopentyl or cyclohexyl, especially tert-butyl, q is 1, 2 or 3, preferably 2 or 3, especially 2, n is an integer from 1 to 30, preferably an integer from 1 to 10, advantageously 1, 2, 3, 4, 5 or 6, e.g. 1, 2, 3 or 4, especially 1, R 3 is an n-valent radical of linear or branched C 1 -C 30 -alkyl, C 2 -C 30 -alkylene, interrupted in each case optionally by one or more oxygen atoms, or, especially where n = 1-12, is an n-valent radical of C 5 -C 12 cycloalkyl, or a radical R 4 [NR 5 -C q H 2q -] p, R 4 is hydrogen, an n-valent radical of linear or branched C 1 -C 30 alkyl, which is optionally interrupted by one or more groups -NR 5 - or, where n = 1-12, is an n-valent radical of C 5 -C 12 cycloalkyl, R 5 independently at each occurrence is hydrogen or methyl or -C q H 2q, preferably hydrogen, and p corresponds to the number of -[NR 5 -C q H 2q -] groups that produces n radicals -C q H 2q - per molecule, k is an integer between 0 and 50, preferably between 10 and 30, m is an integer between 0 and 50, e.g. 1-40, and o is an integer between 0 and 50, preferably between 0 and 30, especially 0, where (k + m + o) > 10, and as further antioxidant at least one benzofuranone derivative of the formula in which a is an integer between 0 and 7, preferably 0-3, R 6 and R 7 independently of one another are H or C 1 -C 8 alkyl, R 8 is H or an aromatic radical where R 9 and R 10 independently of one another are H or C 1 -C 6 alkyl, with not both being a C 1 -C 6 alkyl, R 11 and R 12 independently of one another are H or C 1 -C 6 alkyl, with not both being a C 1 -C 6 alkyl, R 13 is H or OH. R is CH 2 -CH(R I), CH(R II)-CH(R II), CH 2 -C(R II) 2, C(R II) 2 -C(R II) 2, CH 2 -CH-CH 2 -R IV, C 6 H 6 -CH-CH 2, or C 6 H 6 -C(CH 3)-CH 2, R I is C 2 to C 24 alkyl radical or alkene radical, which may be linear or branched R II is C 2 to C 24 alkyl radical or alkene radical, which may be linear or branched R III is C 3 to C 6 alkyl radical, which is arranged linearly, and R IV is OH, Cl, OCH 3, OCH 2 -CH 3, O-CH 2 -CH=CH 2, O-CH=CH 2, molecule residue of singly or multiply epoxidized fats or oils as mono-, di-, and triglycerides, or molecule residue of singly or multiply epoxidized fatty acids or their C 1 -C 24 alkyl esters, R 1 and R 2 independently of one another are straight-chain or branched C 1 -C 8 alkyl, cyclopentyl or cyclohexyl, especially tert-butyl, q is 1, 2 or 3, preferably 2 or 3, especially 2, n is an integer from 1 to 30, preferably an integer from 1 to 10, advantageously 1, 2, 3, 4, 5 or 6, e.g. 1, 2, 3 or 4, especially 1, R 3 is an n-valent radical of linear or branched C 1 -C 30 -alkyl, C 2 -C 30 -alkylene, interrupted in each case optionally by one or more oxygen atoms, or, especially where n = 1-12, is an n-valent radical of C 5 -C 12 cycloalkyl, or a radical R 4 [NR 5 -C q H 2q -] p, R 4 is hydrogen, an n-valent radical of linear or branched C 1 -C 30 alkyl, which is optionally interrupted by one or more groups -NR 5 - or, where n = 1-12, is an n-valent radical of C 5 -C 12 cycloalkyl, R 5 independently at each occurrence is hydrogen or methyl or -C q H 2q, preferably hydrogen, and p corresponds to the number of -[NR 5 -C q H 2q -] groups that produces n radicals -C q H 2q - per molecule, k is an integer between 0 and 50, preferably between 10 and 30, m is an integer between 0 and 50, e.g. 1-40, and o is an integer between 0 and 50, preferably between 0 and 30, especially 0, where (k + m + o) > 10, a is an integer between 0 and 7, preferably 0-3, R 6 and R 7 independently of one another are H or C 1 -C 8 alkyl, R 8 is H or an aromatic radical R 9 and R 10 independently of one another are H or C 1 -C 6 alkyl, with not both being a C 1 -C 6 alkyl, R 11 and R 12 independently of one another are H or C 1 -C 6 alkyl, with not both being a C 1 -C 6 alkyl, R 13 is H or OH.