COPOLYMERIC, HYDROPHOBICALLY MODIFIED POLYASPARTIC ESTERS HAVING INCREASED MOLECULAR MASS AND THEIR USE

The invention describes the preparation of high molecular weight copolymeric polyaspartic esters which have been hydrophobically modified with alkyl radicals having from 6 to 30 carbon atoms. Copolymers derived from polyamino acids, in which at least 75 mol % of the units present consist of structural units of the general formulae (I), (II) or (III) 1 in which the structural elements A are identical or different trifunctional hydrocarbon radicals having 2 carbon atoms of the type (A1) or (A2), where one copolymer consists of at least three units of the formula (I), where R 1 is as defined for R 2 , R 3 or R 4 , where R 2 are one or more radicals from the group of alkali metals, alkaline earth metals, hydrogen or ammonium, [NR 5 R 6 R 7 R 8 ] + , where R 5 to R 8 independently of one another are hydrogen, alkyl or alkenyl having from 1 to 22 carbon atoms or hydroxyalkyl having from 1 to 22 carbon atoms and from 1 to 6 hydroxyl groups and/or their acylation products containing C 1 - to C 22 -carboxylic radicals, R 3 are identical or different, straight-chain or branched, saturated or unsaturated alkyl or alkenyl radicals R 9 having from 6 to 30 carbon atoms, or radicals of the structure -Y-R 9 , where Y is an oligo- or polyoxyalkylene chain having from 1 to 100 oxyalkylene units, R 4 are identical or different, straight-chain or branched, saturated or unsaturated alkyl or alkenyl radicals having from 1 to 5 carbon atoms, the units of the formula (II) are proteinogenic or nonproteinogenic amino acids and are present in an amount of not more than 20% by weight, and X in the formula (III) is one or more di- or polyfunctional radicals derived from molecular-mass-increasing agents, in particular a di- or polyhydroxy compound, a di- or polyamino compound, or aminoalcohols, having a linear, branched or cyclic, saturated, unsaturated or aromatic hydrocarbon structure, optionally oxo- or aza-substituted with O or N atoms in the chain, and at least in each case one radical R 1 must assume the meaning of R 2 and at least one radical R 1 that of R 3 and at least one radical R 1 that of X.