Use of at least one polymer P as a dispersant for gypsum compositions, wherein the polymer P includes: a) a main chain containing hydrocarbon groups, b) at least one side chain including at least one acid group, selected from the group consisting of a carboxylic acid group, a sulfonic acid group, a phosphonic acid group, a phosphoric acid group, or a salt thereof, and c) at least one side chain with a molecular weight M w of at least 1800 g/mol, including at least one polyoxyalkylene group, where the polyoxyalkylene group is connected to the main chain through a linkage including at least one ester, amide, or imide group; wherein the polymer P includes: a) at least one acid unit A of formula; b) at least one structural unit B of formula; and optionally c) at least one additional structural unit C; where R 1 and R 2 each independently stand for H, COOM, CH 2 COOM or an alkyl group with 1 to 5 carbon atoms, where R 3 independently stands for H, CH 3, COOM, or CH 2 COOM; and where R 4 independently stands for a radical of carboxylic acid, sulfonic acid, phosphoric acid, or phosphonic acid or a salt thereof; or where R 3 forms a ring with R 4, to form -CO-O-CO-; where M stands for H, alkali metal, alkaline earth metal, ammonium, ammonium cation, or mixtures thereof; where R 5 independently stands for a radical of formula -(CH 2) x -R 7 -(R 8 O) y -R 9 where R 7 stands for an ester, amide, or imide linkage, preferably for -COO- or -CO-NH-; where R 8 stands for a C 2 -C 6 alkylene group, preferably a C 2 -C 4 alkylene group or a mixture thereof, where R 9 stands for H, a C 1 -C 12 alkyl or cycloalkyl radical, a C 7 -C 20 alkylaryl or aralkyl radical, or a substituted or unsubstituted aryl radical, or a monovalent organic radical with 1 to 30 C atoms, which optionally includes heteroatoms; where x independently stand for the number 0 or 1; where y independently stands for the number 40-250; and where R 6 independently stands for H, CH 3, COOM, CH 2 COOM, or a substituent such as defined for R 5; and where the acid content of the polymer is 1.8 to 2.7 mmol acid groups per gram of polymer, where the acid content SG in mmol/g of polymer is calculated from the formula z * m M WA * m + M WB * n + M WC * o * 1000, where z corresponds to the number of protons which the acid unit A of formula is able to give up; M w is the molecular weight of the respective acid or structural unit(s); and m describes the proportion of the acid unit A of formula in mol% in polymer P, n describes the proportion of the structural unit B of formula in mol% in polymer P, and O describes the proportion of the optionally included structural unit C in mol% in polymer P; and wherein the polymer P is obtainable by or is prepared by means of a polymer-analogous reaction of esterification and/or amidation of a polycarboxylic acid. a) a main chain containing hydrocarbon groups, b) at least one side chain including at least one acid group, selected from the group consisting of a carboxylic acid group, a sulfonic acid group, a phosphonic acid group, a phosphoric acid group, or a salt thereof, and c) at least one side chain with a molecular weight M w of at least 1800 g/mol, including at least one polyoxyalkylene group, where the polyoxyalkylene group is connected to the main chain through a linkage including at least one ester, amide, or imide group; a) at least one acid unit A of formula; b) at least one structural unit B of formula; and optionally c) at least one additional structural unit C; where R 7 stands for an ester, amide, or imide linkage, preferably for -COO- or -CO-NH-; where R 8 stands for a C 2 -C 6 alkylene group, preferably a C 2 -C 4 alkylene group or a mixture thereof, where R 9 stands for H, a C 1 -C 12 alkyl or cycloalkyl radical, a C 7 -C 20 alkylaryl or aralkyl radical, or a substituted or unsubstituted aryl radical, or a monovalent organic radical with 1 to 30 C atoms, which optionally includes heteroatoms; where x independently stand for the number 0 or 1; where y independently stands for the number 40-250; and where R 6 independently stands for H, CH 3, COOM, CH 2 COOM, or a substituent such as defined for R 5; where z corresponds to the number of protons which the acid unit A of formula is able to give up; M w is the molecular weight of the respective acid or structural unit(s); and m describes the proportion of the acid unit A of formula in mol% in polymer P, n describes the proportion of the structural unit B of formula in mol% in polymer P, and O describes the proportion of the optionally included structural unit C in mol% in polymer P; and wherein the polymer P is obtainable by or is prepared by means of a polymer-analogous reaction of esterification and/or amidation of a polycarboxylic acid.