Use of regulator compounds according to anyone of the Formulas 1A, 1B, 1C, 1D, 1E, 1F, 1G, 1H and 1I: wherein R 1 stands for an optionally substituted secondary or tertiary alkyl or secondary or tertiary aralkyl and wherein R 1 is selected from isopropyl, sec -butyl, tert- butyl, 3-pentyl, tert -amyl, cyclohexyl, 2,4-dimethyl-3-pentyl, 2,2,4-trimethyl-3-pentyl, 1-adamantyl, 1-phenylethyl, 2-methyl-1-phenyl-1-propyl, diphenylmethyl, 1-cyanocyclohexyl, 1-(methoxycarbonyl)-2-methyl-1-propyl, 1-(diethoxyphosphoryl)-2,2-dimethylpropyl, 1-hydroxy-2-methyl-2-propyl and 1,3-dihydroxy-2-(hydroxymethyl)-2-propyl; Z 1 stands for -CN or a carboxylic acid ester of formula C OR 21; Z 2 is chosen from the group of -CN, carboxylic acid, salts of carboxylic acids, carboxylic acid ester of formula C OR 22, carboxylic acid amides, (hetero)aryl, alkenyl and halogen; R 2, R 4 and R 5 are each independently chosen from H, methyl and ethyl; R 3 is chosen from H, methyl, ethyl, -CN, C OMe or C OEt; R 7 stands for a primary alkyl or primary aralkyl, -CN or hydrogen; Y stands for a bridging group and n is 2, 3, 4, 5 or 6; in case R 1 stands for tertiary alkyl or tertiary aralkyl, R 6 stands for a primary alkyl or primary aralkyl, -CN or a carboxylic acid ester of formula C OR 26; in case R 1 stands for a secondary alkyl or secondary aralkyl, R 6 stands for a primary or secondary alkyl or primary or secondary aralkyl, -CN, a carboxylic acid ester of formula C OR 26 or a phosphonic acid ester of formula P (OR 27) 2, a (hetero)aryl or an alkenyl; for the polymerization of vinyl monomers; wherein R 21 stands for methyl, ethyl, tert-butyl, benzyl, cyclohexyl, 2-hydroxyethyl, 2-methoxyethyl, 2-acetoacetoxyethyl and 2,3-epoxypropyl; wherein R 7 is chosen from methyl, ethyl, 1-propyl, isobutyl, 2-ethylbutyl, 2-ethylhexyl, benzyl, 2-phenylethyl, -CN and hydrogen; wherein R 22, R 26 and R 27 are independently chosen from the group consisting of methyl, ethyl, n -butyl, tert -butyl, benzyl, cyclohexyl, 2-hydroxyethyl, 2-acetoacetoxyethyl and 2,3-epoxypropyl and wherein Y is selected from the group consisting of 1,2-ethanediyl, 2,2-dimethyl-1,3-propanediyl, 1,4-butanediyl, 1,6-hexanediyl, pentaerythrityl and dipenta-erythrityl. R 1 stands for an optionally substituted secondary or tertiary alkyl or secondary or tertiary aralkyl and wherein R 1 is selected from isopropyl, sec -butyl, tert- butyl, 3-pentyl, tert -amyl, cyclohexyl, 2,4-dimethyl-3-pentyl, 2,2,4-trimethyl-3-pentyl, 1-adamantyl, 1-phenylethyl, 2-methyl-1-phenyl-1-propyl, diphenylmethyl, 1-cyanocyclohexyl, 1-(methoxycarbonyl)-2-methyl-1-propyl, 1-(diethoxyphosphoryl)-2,2-dimethylpropyl, 1-hydroxy-2-methyl-2-propyl and 1,3-dihydroxy-2-(hydroxymethyl)-2-propyl; Z 1 stands for -CN or a carboxylic acid ester of formula C OR 21; Z 2 is chosen from the group of -CN, carboxylic acid, salts of carboxylic acids, carboxylic acid ester of formula C OR 22, carboxylic acid amides, (hetero)aryl, alkenyl and halogen; R 2, R 4 and R 5 are each independently chosen from H, methyl and ethyl; R 3 is chosen from H, methyl, ethyl, -CN, C OMe or C OEt; R 7 stands for a primary alkyl or primary aralkyl, -CN or hydrogen; Y stands for a bridging group and n is 2, 3, 4, 5 or 6; in case R 1 stands for tertiary alkyl or tertiary aralkyl, R 6 stands for a primary alkyl or primary aralkyl, -CN or a carboxylic acid ester of formula C OR 26; in case R 1 stands for a secondary alkyl or secondary aralkyl, R 6 stands for a primary or secondary alkyl or primary or secondary aralkyl, -CN, a carboxylic acid ester of formula C OR 26 or a phosphonic acid ester of formula P (OR 27) 2, a (hetero)aryl or an alkenyl; for the polymerization of vinyl monomers; wherein R 21 stands for methyl, ethyl, tert-butyl, benzyl, cyclohexyl, 2-hydroxyethyl, 2-methoxyethyl, 2-acetoacetoxyethyl and 2,3-epoxypropyl; wherein R 7 is chosen from methyl, ethyl, 1-propyl, isobutyl, 2-ethylbutyl, 2-ethylhexyl, benzyl, 2-phenylethyl, -CN and hydrogen; wherein R 22, R 26 and R 27 are independently chosen from the group consisting of methyl, ethyl, n -butyl, tert -butyl, benzyl, cyclohexyl, 2-hydroxyethyl, 2-acetoacetoxyethyl and 2,3-epoxypropyl and wherein Y is selected from the group consisting of 1,2-ethanediyl, 2,2-dimethyl-1,3-propanediyl, 1,4-butanediyl, 1,6-hexanediyl, pentaerythrityl and dipenta-erythrityl.