Dispersing agent

A process for preparing compounds of formula (I), formula (II), or mixtures thereof,

• wherein
• n is an integer greater than or equal to 1 R1 is an aliphatic, linear or branched hydrocarbon radical having 1 to 10 carbon atoms, a hydrogen atom, the structural unit —O—X, or the structural unit —CH2—O—X,
• X corresponds to formula (III)
• in which
• a is an integer from 2 to 6,
• b is an integer from 0 to 3,
• c is an integer from 20 to 28,
• m is 1 or 2,
• R2 is an aliphatic, linear or branched hydrocarbon radical having 1 to 10 carbon atoms,
• Y is hydrogen, —SO3M, —SO2M, —PO3M2 or —CH2COOM, and
• M is a cation,
• by
• 1. providing an alcohol resulting from formula I or formula II by formal replacement of the X radical with H,
• 2. alkoxylating the alcohol with, per active hydrogen atom, 2 to 6 mol of styrene oxide and optionally with up to 3 mol of a C3- to C12-alkylene oxide, wherein the alkoxylation can be effected simultaneously with styrene oxide and the C3- to C32-alkylene oxide or sequentially,
• 3. optionally repeating step 2 once or twice, and
• 4. alkoxylating the product thus obtained with 20 to 28 mol of ethylene oxide per active hydrogen atom.

A dispersing agent for aqueous formulations of crop protection agent, comprising at least one compound of formula (I), formula (II), or mixtures thereof,

• wherein
• n is an integer greater than or equal to 1
• R1 is an aliphatic, linear or branched hydrocarbon radical having 1 to 10 carbon atoms, a hydrogen atom, the structural unit —O—X, or the structural unit —CH2—O—X,
• X corresponds to formula (III)
• in which
• a is an integer from 2 to 6,
• b is an integer from 0 to 3,
• c is an integer from 20 to 28,
• m is 1 or 2,
• R2 is an aliphatic, linear or branched hydrocarbon radical having 1 to 10 carbon atoms,
• Y is hydrogen, —SO3M, —SO2M, —PO3M2 or —CH2COOM, and
• M is a cation.