Water-mixed metal working fluids containing ether pyrrolidone carboxylic acids
The invention relates to compositions containing a basic oil or base oil, 10 to 50 percent by weight of ether pyrrolidone carboxylic acids of formula (1) or the salts thereof of formula (1), wherein R 1 represents C 8 -C 30 -alkyl, C 8 -C 30 -alkenyl, C 6 -C 30 -alyl, C 7 -C 30 -alkylaryl, M represents hydrogen, alkali metal, alkaline earth metal, or ammonium, X represents C 2 -C 6 -alkylene, or a poly(oxyalkylene) group of formula (2), wherein I is a number ranging from 1 to 50, m, n are numbers ranging from 0 to 50 independently of l and independently of one another, R 2 , R 3 , and R 4 independently represent hydrogen, CH 3 , or CH 2 CH 3 , Y represents C 2 -C 6 -alkylene, said compositions further containing a specific amount of a pH regulator/neutralizer such that a 5 percent by weight emulsion of the composition in deionized water has a pH ranging from 7 to 11.
1. A composition comprising a base oil, 10% to 50% by weight of at least one etherpyrrolidonecarboxylic acid of the formula 1 or salt thereof
in which
R 1 is C 8 —C 30 -alkyl, C 8 —C 30 -alkenyl, C 6 —C 30 -aryl, C 7 —C 30 -alkylaryl
M is hydrogen, alkali metal, alkaline earth metal or ammonium
X is C 2 —C 6 -alkylene, or a poly(oxyalkylene) group of the formula (2)
in which
I is a number 1 to 50,
m, n independently of I and of one another are a number from 0 to 50,
R 2 , R 3 , R 4 independently of one another are hydrogen, CH 3 or CH 2 CH 3
Y is C 2 —C 6 -alkylene,
and also a pH regulator/neutralizing agent in an amount such that a 5% by weight emulsion of the composition in deionized water has a pH of between 7 and 11.
2. A composition as claimed in claim 1 , in which R 1 is a C 8 —C 22 -alkyl or alkenyl group.
3. A composition as claimed in claim 1 , in which X and Y independently of one another are selected from the group consisting of —(CHR 16 ) k —with k=2, 3 or 4 and R 16 =H, CH 3 or —CH 2 —CH 3 .
4. A composition as claimed in claim 1 , in which I is a number from 2 to 10.
5. A composition as claimed in claim 1 , in which m and n independently of one another denote a number from 1 to 10.
6. A composition as claimed in claim 1 , in which the neutralizing agent is selected from the group consisting of
a) amines of the formula (3)
NR 7 R 8 R 9 (3)
in which R 7 , R 8 and R 9 independently of one another are H or a hydrocarbon radical having 1 to 100 carbon atoms, and
b) oxides and hydroxides of alkali metals or alkaline earth metals.
7. A composition as claimed in claim 1 , in which 1% to 50% by weight, based on the composition, of non-ionic emulsifiers are present.
8. A composition as claimed in claim 1 , in which 1% to 20% by weight, based on the composition, of corrosion inhibitors are present.
9. A composition as claimed in claim 1 , in which 0.1% to 5% by weight, based on the composition, of extreme pressure (EP) and/or anti-wear (AW) additives are present.
10. A composition as claimed in claim 1 , in which the base oil is present up to 100% by weight.
11. A process for producing a hydrous metalworking fluid comprising the step of mixing a composition as claimed in claim 1 with water in a weight ratio of 1:5 to 1:100.
12. A corrosion inhibitor in hydrous metalworking fluids which comprise a base oil and a neutralizing agent such that the pH of the hydrous metalworking fluids is between 7 and 11 comprising 0.1% to 10% by weight of at least one etherpyrrolidonecarboxylic acid or salt thereof according to formula (1)
in which
R 1 is C 8 —C 30 -alkyl, C 8 —C 30 -alkenyl, C 6 —C 30 -aryl, C 7 -C 30 -alkylaryl
M is hydrogen, alkali metal, alkaline earth metal or ammonium
X is C 2 -C 6 -alkylene, or a poly(oxyalkylene) group of the formula (2)
in which
I is a number 1 to 50,
m, n independently of I and of one another are a number from 0 to 50,
R 2 , R 3 , R 4 independently of one another are hydrogen, CH 3 or CH 2 CH 3
Y is C 2 —C 6 -alkylene.