Corrosion protection coatings

Abstract

The present invention relates to new coating materials for corrosion control.

1 . A compound (D) represented by formula (I) 
     
       
         
         
             
             
         
       
       wherein 
       R 1 , R 3  and R 4  are selected independently of one another from the group consisting of C 1 -C 18  alkyl, C 6 -C 12  aryl, C 5 -C 12  cycloalkyl, and five- to six-membered heterocycles which comprise oxygen, nitrogen or sulfur, or mixtures thereof, and may each optionally be substituted by aryl, alkyl, aryloxy, alkyloxy, heteroatoms or heterocycles or mixtures thereof, 
       R 1  and R 3  independently of one another may additionally be hydrogen, and 
       R 2  is a divalent organic radical, and 
       X is selected from the group consisting of —S—, —SO— and —SO 2 —. 
     
   
   
       2 . The compound according to  claim 1 , wherein R 1  is hydrogen, methyl, ethyl, isopropyl or phenyl. 
   
   
       3 . The compound according to  claim 1 , wherein X is a sulfide group. 
   
   
       4 . The compound according to  claim 1 , wherein R 2  is 1,2-ethylene, 1,2-propylene, 1,3-propylene, 1,2-butylene, 1,2-phenylene or 1,4-phenylene. 
   
   
       5 . The compound according to  claim 1 , wherein R 2  is 1,2-ethylene. 
   
   
       6 . The compound according to  claim 1 , wherein R 3  is hydrogen, methyl, ethyl, isopropyl, n-butyl, tert-butyl, phenyl, benzyl, cyclohexyl or cyclopentyl. 
   
   
       7 . The compound according to  claim 1 , wherein R 4  comprises 3 to 10 carbon atoms. 
   
   
       8 . The compound according to  claim 1 , wherein R 4  is methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, pentyl, hexyl, heptyl, octyl, 2-ethylhexyl, phenyl or benzyl. 
   
   
       9 . The compound according to  claim 1 , wherein the compound (D) is selected from the group consisting of
 N-(2-mercaptoethyl)pentanamide (R 1 =H, X=—S—, R 2 =1,2-ethylene, R 3 =H and R 4 =n-butyl),   N-(2-mercaptoethyl)butanamide (R 1 =H, X=—S—, R 2 =1,2-ethylene, R 3 =H and R 4 =n-propyl),   N-(2-mercaptoethyl)hexanamide (R 1 =H, X=—S—, R 2 =1,2-ethylene, R 3 =H and R 4 =n-pentyl),   N-(2-mercaptoethyl)-2-ethylhexanamide (R 1 =H, X=—S—, R 2 =1,2-ethylene, R 3 =H and R 4 =1-ethylpentyl),   N-(2-mercaptoethyl)-2,2-dimethylpropionamide (R 1 =H, X=—S—, R 2 =1,2-ethylene, R 3 =H and R 4 =tert-butyl),   N-(2-mercaptoethyl)benzamide (R 1 =H, X=—S—, R 2 =1,2-ethylene, R 3 =H, and R 4 =phenyl) and   N-(2-mercaptoethyl)-2-phenylacetamide (R 1 =H, X=—S—, R 2 =1,2-ethylene, R 3 =H, and R 4 =benzyl).   
   
   
       10 . The compound according to  claim 1 , wherein the group —X—R 1  is a sulfanyl group (—S—H). 
   
   
       11 . The compound according to  claim 10 , wherein further to the compound (D) there is a disulfide (D1) of the formula (II) 
     
       
         
         
             
             
         
       
       wherein R 2 , R 3  and R 4  have the definitions stated in  claim 10 , 
       the fraction of the disulfide (D1) not exceeding 30% by weight, based on the compounds (D). 
     
   
   
       12 . The compound according to  claim 1 , wherein the compound (D) is a compound (D2) of the formula (II) 
     
       
         
         
             
             
         
       
       wherein R 5  is a divalent organic radical and the radicals R 1 , X, R 2 , and R 3  are defined as in  claim 1 . 
     
   
   
       13 . (canceled) 
   
   
       14 . A method of applying corrosion control coats to metallic surfaces, which comprises treating the metallic surface with a formulation which comprises at least one binder, at least one pigment, at least one filler, and at least one compound (D). 
   
   
       15 . A mercaptoethylamide for corrosion control, selected from the group consisting of
 N-(2-mercaptoethyl)-2-ethylhexanamide (R 1 =H, X=—S—, R 2 =1,2-ethylene, R 3 =H and R 4 =1-ethylpentyl), and   N-(2-mercaptoethyl)-2,2-dimethylpropionamide (R 1 =H, X=—S—, R 2 =1,2-ethylene, R 3 =H and R 4 =tert-butyl).   
   
   
       16 . The method of  claim 14 , wherein compound D is represented by formula (I) 
     
       
         
         
             
             
         
       
       wherein 
       R 1 , R 3  and R 4  are selected independently of one another from the group consisting of C 1 -C 18  alkyl, C 6 -C 12  aryl, C 5 -C 12  cycloalkyl, and five- to six-membered heterocycles which comprise oxygen, nitrogen or sulfur, or mixtures thereof, and may each optionally be substituted by aryl, alkyl, aryloxy, alkyloxy, heteroatoms or heterocycles or mixtures thereof, 
       R 2  is a divalent organic radical, and 
       X is selected from the group consisting of —S—, —SO— and —SO 2 —. 
     
   
   
       17 . The method of  claim 16 , wherein R 1  is hydrogen, methyl, ethyl, isopropyl, or phenyl. 
   
   
       18 . The method of  claim 16 , wherein X is a sulfide group. 
   
   
       19 . The method of  claim 16 , wherein R 2  is 1,2-ethylene, 1,2-propylene, 1,3-propylene, 1,2-butylene, 1,2-phenylene or 1,4-phenylene. 
   
   
       20 . The method of  claim 14 , wherein the compound (D) is selected from the group consisting of
 N-(2-mercaptoethyl)pentanamide (R 1 =H, X=—S—, R 2 =1,2-ethylene, R 3 =H and R 4 =n-butyl),   N-(2-mercaptoethyl)butanamide (R 1 =H, X=—S—, R 2 =1,2-ethylene, R 3 =H and R 4 =n-propyl),   N-(2-mercaptoethyl)hexanamide (R 1 =H, X=—S—, R 2 =1,2-ethylene, R 3 =H and R 4 =n-pentyl),   N-(2-mercaptoethyl)-2-ethylhexanamide (R 1 =H, X=—S—, R 2 =1,2-ethylene, R 3 =H and R 4 =1-ethylpentyl),   N-(2-mercaptoethyl)-2,2-dimethylpropionamide (R 1 =H, X=—S—, R 2 =1,2-ethylene, R 3 =H and R 4 =tert-butyl),   N-(2-mercaptoethyl)benzamide (R 1 =H, X=—S—, R 2 =1,2-ethylene, R 3 =H, and R 4 =phenyl) and   N-(2-mercaptoethyl)-2-phenylacetamide (R 1 =H, X=—S—, R 2 =1,2-ethylene, R 3 =H, and R 4 =benzyl).   
   
   
       21 . The method of  claim 14 , wherein the compound (D) is selected from the group consisting of
 N-(2-mercaptoethyl)-2-ethylhexanamide (R 1 =H, X=—S—, R 2 =1,2-ethylene, R 3 =H and R 4 =1-ethylpentyl), and   N-(2-mercaptoethyl)-2,2-dimethylpropionamide (R 1 =H, X=—S—, R 2 =1,2-ethylene, R 3 =H and R 4 =tert-butyl).