| 摘要 |
A method for the preparation of betaines is disclosed, the betaines having the general formula R1CONH(CH2)xN(+)R2R3(CH2)yCOO(-) in which R1 is the alkyl residue of a fatty acid with 6 to 18 carbon atoms, R2 and R3 are the same or different and represent alkyl residues with 1 to 4 carbon atoms, x=2 or 3, and y=1, 2 or 3. The betaines are prepared by quaternizing fatty acid amides having the formula R1CONH(CH2)xNR2R3 with omega -halogenalkylcarboxylic acids having the formula X(CH2)yCOOH wherein X is a halogen residue, and carrying out the quaternization at a pH of 7.5 to 10.5 measured at 98 DEG C. The reaction product obtained from the process is essentially free of unreacted amides and organically linked chlorine and thus avoids the skin irritations normally associated with compounds in which such betaines are used.
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