- Process to prepare a precipitated calcium carbonate comprising the following steps: (i) providing CaO, which is optionally partially or fully slaked (hereafter "calcium source"); (ii) providing a CO 2 -comprising gas; (iii) contacting said calcium source of step (i) and said CO 2 -comprising gas of step (ii) in an aqueous environment in a reactor, in one or more steps; (iv) obtaining a PCC-comprising suspension; (v) optionally concentrating said PCC-comprising suspension of step (iv); (vi) optionally adding dispersing additives to the suspension of step (iv) and/or (v); characterised in that: - at least one polymer resulting from the polymerisation of the following monomers, where such monomers are present in said polymer in the following % monomer units relative to the total monomer units forming said polymer, is present during step (iii): a) from 10 % to 99 %, preferably from 50 % to 98 %, more preferably from 80 % to 97 %, and even more preferably from 85 % to 95 %, of at least one vinyl group-comprising monomer not comprising Formula, b) from 1 % to 90 %, preferably from 2 % to 50 %, more preferably from 3 % to 20 %, and even more preferably from 5 % to 15 %, of at least one vinyl group-comprising monomer having at least one substituent comprising Formula: wherein: - m, n, p and q are whole numbers having a value of less than 150, and at least one of m, n, p and q has a value of greater than 0, such that 25 ≤ (m+n+p)q ≤ 150, and preferably such that 50 ≤ (m+n+p)q ≤ 150; - R represents a functional linking group selected from ethers, esters or amides, - R 1 and R 2 are the same or different, and represent hydrogen or alkyl groups having 1 to 4 carbon atoms, - R' represents hydrogen or a hydrocarbon radical having 1 to 40, preferably 1 to 3, carbon atoms, R' being even more preferably a methyl radical or hydrogen, the sum of the monomer unit percentages of monomers a) and b) being equal to 100 %. (i) providing CaO, which is optionally partially or fully slaked (hereafter "calcium source"); (ii) providing a CO 2 -comprising gas; (iii) contacting said calcium source of step (i) and said CO 2 -comprising gas of step (ii) in an aqueous environment in a reactor, in one or more steps; (iv) obtaining a PCC-comprising suspension; (v) optionally concentrating said PCC-comprising suspension of step (iv); (vi) optionally adding dispersing additives to the suspension of step (iv) and/or (v); - at least one polymer resulting from the polymerisation of the following monomers, where such monomers are present in said polymer in the following % monomer units relative to the total monomer units forming said polymer, is present during step (iii): a) from 10 % to 99 %, preferably from 50 % to 98 %, more preferably from 80 % to 97 %, and even more preferably from 85 % to 95 %, of at least one vinyl group-comprising monomer not comprising Formula, b) from 1 % to 90 %, preferably from 2 % to 50 %, more preferably from 3 % to 20 %, and even more preferably from 5 % to 15 %, of at least one vinyl group-comprising monomer having at least one substituent comprising Formula: wherein: - m, n, p and q are whole numbers having a value of less than 150, and at least one of m, n, p and q has a value of greater than 0, such that 25 ≤ (m+n+p)q ≤ 150, and preferably such that 50 ≤ (m+n+p)q ≤ 150; - R represents a functional linking group selected from ethers, esters or amides, - R 1 and R 2 are the same or different, and represent hydrogen or alkyl groups having 1 to 4 carbon atoms, - R' represents hydrogen or a hydrocarbon radical having 1 to 40, preferably 1 to 3, carbon atoms, R' being even more preferably a methyl radical or hydrogen, a) from 10 % to 99 %, preferably from 50 % to 98 %, more preferably from 80 % to 97 %, and even more preferably from 85 % to 95 %, of at least one vinyl group-comprising monomer not comprising Formula, b) from 1 % to 90 %, preferably from 2 % to 50 %, more preferably from 3 % to 20 %, and even more preferably from 5 % to 15 %, of at least one vinyl group-comprising monomer having at least one substituent comprising Formula: wherein: - m, n, p and q are whole numbers having a value of less than 150, and at least one of m, n, p and q has a value of greater than 0, such that 25 ≤ (m+n+p)q ≤ 150, and preferably such that 50 ≤ (m+n+p)q ≤ 150; - R represents a functional linking group selected from ethers, esters or amides, - R 1 and R 2 are the same or different, and represent hydrogen or alkyl groups having 1 to 4 carbon atoms, - R' represents hydrogen or a hydrocarbon radical having 1 to 40, preferably 1 to 3, carbon atoms, R' being even more preferably a methyl radical or hydrogen, - m, n, p and q are whole numbers having a value of less than 150, and at least one of m, n, p and q has a value of greater than 0, such that 25 ≤ (m+n+p)q ≤ 150, and preferably such that 50 ≤ (m+n+p)q ≤ 150; - R represents a functional linking group selected from ethers, esters or amides, - R 1 and R 2 are the same or different, and represent hydrogen or alkyl groups having 1 to 4 carbon atoms, - R' represents hydrogen or a hydrocarbon radical having 1 to 40, preferably 1 to 3, carbon atoms, R' being even more preferably a methyl radical or hydrogen,