Esters of phosphorus-oxygen acids, these esters comprising alkoxy groups, and their use as corrosion inhibitors and flameproofing agents

Abstract

The invention relates to esters or ester salts of phosphorus-oxygen acids, these esters or ester salts comprising alkoxy groups, and to the use of compounds of this type as corrosion inhibitors, particularly in alkaline media, and as flameproofing agents.

1 . A corrosion inhibitor which comprises an alkoxy-comprising ester of phosphorus-oxygen acids of the formula  
       R 3 —NR 4   k —[(CH 2 ) n —PO(OR 1 )(OR 2 )] m    (A)  or  [(R 1 O)(R 2 O)OP—(CH 2 ) n —] m —NR 4   k —R 5 —NR 4   k —[—(CH 2 ) n —PO(OR 1 )(OR 2 )] m    (B)  
     and/or 
 analkoxy-comprising ester salt of phosphorus-oxygen acids of the formula  
   R 3 —NR 4   k —[(CH 2 ) n —PO(OR 1 )(OM)] m    (C)  or  [(MO)(R 1 O)OP—(CH 2 ) n —] m —NR 4   k —R 5 —NR 4   k —[—(CH 2 ) n —PO(OR 1 )(OM)] m    (D)  
 where  
 n is an integer from 0 to 10,  
 m+k=2 and m is 1 or 2 and k is 0 or 1,  
 at least one of the radicals R 1 , R 2  and, if appropriate, R 3  is alkoxy of the formula —[CH 2 —CHR 6 —O] l R 7 , where l is from 2 to 30 and R 6  and R 7  are each H or CH 3 ,  
 and, where, they are not alkoxy groups, R 1  and R 2  are straight-chain or branched, unsubstituted or substituted C 1 - to C 6 -alkyl,  
 and, where it is not an alkoxy group, R 3  is straight-chain or branched, unsubstituted or substituted C 1 - to C 20 -alkyl or aryl,  
 R 4  is H or straight-chain or branched, unsubstituted or substituted C 1 - to C 6 -alkyl  
 R 5  is a divalent bridging group, and  
 M is at least one cation selected from the group consisting of alkali metal, alkaline earth metal or amnionium ions.  
 
   
   
       2 . The inhibitor according to  claim 1 , wherein the corrosion inhibitor is used in an alkaline medium.  
   
   
       3 . The inhibitor according to  claim 1 , wherein the medium is an aqueous medium.  
   
   
       4 . The inhibitor according to  claim 1 , wherein n is 0 or 1.  
   
   
       5 . The inhibitor according to  claim 1 , wherein k and m are each 1.  
   
   
       6 . The inhibitor according to  claim 1 , wherein l is from 3 to 20.  
   
   
       7 . The inhibitor according to  claim 1 , wherein R 6  is H.  
   
   
       8 . An alkoxy-comprising ester salt of phosphorus-oxygen acids of the formula  
       R 3 —NR 4   k —[(CH 2 ) n —PO(OR 1 )(OM)] m    (C)  or  [(MO)(R 1 O)OP—(CH 2 ) n —] m —NR 4   k —R 5 —NR 4   k —[—(CH 2 ) n —PO(OR 1 )(OM)] m    (D)  
     where 
 n is an integer from 0 to 10,  
 m+k=2 and m is 1 or 2 and k is 0 or 1,  
 at least one of the radicals R 1  and, if appropriate, R 3  is alkoxy of the formula —[CH 2 —CHR 6 —O] l R 7 , where l is from 2 to 30 and R 6  and R 7  are each H or CH 3 ,  
 and, where it is not an alkoxy group, R 1  is straight-chain or branched, unsubstituted or substituted C 1 - to C 6 -alkyl,  
 and, where it is not an alkoxy group, R 3  is straight-chain or branched, unsubstituted or substituted C 1 - to C 20 -alkyl or aryl,  
 R 4  is H or straight-chain or branched, unsubstituted or substituted C 1 - to C 6 -alkyl and  
 R 5  is a divalent bridging group, and  
 M is at least one cation selected from the group consisting of alkali metal, alkaline earth metal or ammonium ions.  
 
   
   
       9 . An alkoxy-comprising ester of phosphorus-oxygen acids of the formula  
       R 3 —NR 4   k —[(CH 2 ) n —PO(OR 1 )(OR 2 )] m    (A)  or  [(R 1 O)(R 2 O)OP—(CH 2 ) n —] m —NR 4   k —R 5 —NR 4   k —[—(CH 2 ) n —PO(OR 1 )(OR 2 )] m    (B)  
     where 
 n is an integer from 0 to 10,  
 m+k=2 and m is 1 or 2 and k is 0 or 1,  
 least one of the radicals R 1 , R 2  and, if appropriate, R 3  is alkoxy of the formula —[CH 2 —CHR 6 —O] l CH 3  where l is from 2 to 30 and R 6  is H or CH 3 ,  
 and, where they are not alkoxy groups, R 1  and R 2  are straight-chain or branched, unsubstituted or substituted C 1 - to C 6 -alkyl,  
 and, where it is not an alkoxy group, R 3  is straight-chain or branched, unsubstituted or substituted C 1 - to C 20 -alkyl or aryl,  
 R 4  is H or straight-chain or branched, unsubstituted or substituted C 1 - to C 6 -alkyl and  
 R 5  is a divalent bridging group.  
 
   
   
       10 . The inhibitor according to  claim 2 , wherein n is 0 or 1.  
   
   
       11 . The inhibitor according to  claim 10 , wherein k and m are each 1.  
   
   
       12 . The inhibitor according to  claim 11 , wherein l is from 3 to 20.  
   
   
       13 . The inhibitor according to  claim 12 , wherein R 6  is H.  
   
   
       14 . The inhibitor according to  claim 11 , wherein l is from 5 to 15 and n is 1.  
   
   
       15 . The inhibitor according to  claim 1 , wherein R 1  or R 2  is 2-methoxyethyl.  
   
   
       16 . The inhibitor according to  claim 1 , wherein R 4  is H, methyl or 2-methoxyethyl.  
   
   
       17 . The alkoxy according to  claim 9 , wherein R 4  is H, methyl or 2-methoxyethyl.