Polymer compositions comprising at least one polyurethane polymer and at least one siloxane-organic copolymer having 100 to 3000 siloxane units per siloxane segment and at least one organic segment having at least one group selected from ester groups, amide groups, urethane groups, urea groups, and thiourea groups, wherein comprises siloxane-organic copolymers of the general formula where R may each be identical or different and is a monovalent, SiC-bonded hydrocarbon radical having 1 to 20 carbon atoms and optionally substituted by fluorine or chlorine, X may each be identical or different and is an alkylene radical having 1 to 20 carbon atoms in which methylene units not adjacent to one another may have been replaced by -O- groups, A may each be identical or different and is an oxygen atom, sulfur atom or an amino group -NR'-, Z may each be identical or different and is an oxygen atom or an amino group -NR'-, R' may each be identical or different and is a hydrogen atom or an alkyl radical having 1 to 10 carbon atoms, Y may each be identical or different and is a divalent hydrocarbon radical having 1 to 20 carbon atoms and optionally substituted by fluorine or chlorine, D may each be identical or different and is a divalent hydrocarbon radical which is optionally substituted by fluorine, chlorine or C 1 -C 6 alkyl ester groups and in which methylene units not adjacent to one another may have been replaced by -O-, -COO-, -OCO- or -OCOO- groups, B may each be identical or different and is a hydrogen atom or a functional or nonfunctional organic or silicon-organic radical, n may each be identical or different and is a number from 99 to 2999, a is a number which is at least 1, b is 0 or a number from 1 to 100, c is 0 or a number from 1 to 100, d is a number which is at least 1, and e is a number which is 0 or 1. at least one polyurethane polymer and at least one siloxane-organic copolymer having 100 to 3000 siloxane units per siloxane segment and at least one organic segment having at least one group selected from ester groups, amide groups, urethane groups, urea groups, and thiourea groups, wherein comprises siloxane-organic copolymers of the general formula where R may each be identical or different and is a monovalent, SiC-bonded hydrocarbon radical having 1 to 20 carbon atoms and optionally substituted by fluorine or chlorine, X may each be identical or different and is an alkylene radical having 1 to 20 carbon atoms in which methylene units not adjacent to one another may have been replaced by -O- groups, A may each be identical or different and is an oxygen atom, sulfur atom or an amino group -NR'-, Z may each be identical or different and is an oxygen atom or an amino group -NR'-, R' may each be identical or different and is a hydrogen atom or an alkyl radical having 1 to 10 carbon atoms, Y may each be identical or different and is a divalent hydrocarbon radical having 1 to 20 carbon atoms and optionally substituted by fluorine or chlorine, D may each be identical or different and is a divalent hydrocarbon radical which is optionally substituted by fluorine, chlorine or C 1 -C 6 alkyl ester groups and in which methylene units not adjacent to one another may have been replaced by -O-, -COO-, -OCO- or -OCOO- groups, B may each be identical or different and is a hydrogen atom or a functional or nonfunctional organic or silicon-organic radical, n may each be identical or different and is a number from 99 to 2999, a is a number which is at least 1, b is 0 or a number from 1 to 100, c is 0 or a number from 1 to 100, d is a number which is at least 1, and e is a number which is 0 or 1. R may each be identical or different and is a monovalent, SiC-bonded hydrocarbon radical having 1 to 20 carbon atoms and optionally substituted by fluorine or chlorine, X may each be identical or different and is an alkylene radical having 1 to 20 carbon atoms in which methylene units not adjacent to one another may have been replaced by -O- groups, A may each be identical or different and is an oxygen atom, sulfur atom or an amino group -NR'-, Z may each be identical or different and is an oxygen atom or an amino group -NR'-, R' may each be identical or different and is a hydrogen atom or an alkyl radical having 1 to 10 carbon atoms, Y may each be identical or different and is a divalent hydrocarbon radical having 1 to 20 carbon atoms and optionally substituted by fluorine or chlorine, D may each be identical or different and is a divalent hydrocarbon radical which is optionally substituted by fluorine, chlorine or C 1 -C 6 alkyl ester groups and in which methylene units not adjacent to one another may have been replaced by -O-, -COO-, -OCO- or -OCOO- groups, B may each be identical or different and is a hydrogen atom or a functional or nonfunctional organic or silicon-organic radical, n may each be identical or different and is a number from 99 to 2999, a is a number which is at least 1, b is 0 or a number from 1 to 100, c is 0 or a number from 1 to 100, d is a number which is at least 1, and e is a number which is 0 or 1.