Perfluoropolyether polymers

A block copolymer, copolymer (PO-O), comprising a first and a second perfluoropolyether chain, PFPE chain, wherein each of said first and second PFPE chain is a chain (Rf) or is a chain (RfO-O) wherein (RfO-O) is a repeating units complying with any one of formulae (i) to (v) for (R°) and having a peroxidic content (PO), defined as grams of active oxygen (Mw=16) in 100 g of PFPE peroxy between 0.1 and 4, each of said first and second PFPE chain having two chain ends, wherein the first chain end of each one of said first and second PFPE chain is a chain end of copolymer (P) and each one comprises a group selected from a perfluorinated linear or branched alkyl chain comprising from 1 to 6 carbon atoms, —C(═O)F and —OC(═O)F;

• and the second chain ends of said first and second PFPE chain are bonded to each other via:
• at least one first block, block (1), complying with formula (I)
• wherein
• L{circumflex over ( )} is an integer from 1 to 250;
• R100, R101, R102 and R103 are each independently selected from halogen atom;
• linear or branched alkyl chain comprising from 1 to 6 carbon atoms;
• —OR200 wherein R200 is a linear or branched perfluorinated chain comprising from 1 to 6 carbon atoms or a group of formula —CF2OR201 in which R201 is a perfluorinated alkyl chain comprising from 1 to 6 carbon atoms, optionally interrupted by one or more oxygen ether atoms;
• or one of R100 and R101 and one of R102 and R103 are a fluorine atom and the other of R100 and R101 and the other of R102 and R103 together form a perhalogenated cyclic ring having from 4 to 6 members, optionally comprising heteroatoms;
• L is 0 or an integer from 1 to 250, and
• D is a group of formula —(CR100*R101*—CR102*R103*)— wherein at least one of R100*, R101* R102*and R103* is different from R100, R101, R102, and R103, such that (D) is different from —[CR100R101—CR102R103]L{circumflex over ( )};
• with the proviso that, when L{circumflex over ( )} and L are both different from 0, the recurring units are statistically distributed;
• at least one second block, block (2), complying with formula (II)
• wherein
• m is an integer from 1 to 5;
• R5 to R8, each independently, is selected from the group consisting of —F, perfluorinated linear or branched alkyl chain having from 1 to 6 carbon atoms, and group of formula (III):
• wherein
• R20 is a sigma bond, or linear or branched perfluoroalkyl chain comprising from 1 to 12 carbon atoms, optionally comprising and/or interrupted by at least one oxygen atom,
• X is a functional group;
• and
• y is an integer equal to 1 or 2;
• with the proviso that in formula (II), at least one, of R5 to R8 is group of formula (III);
• and
• optionally, at least one third block, block (3), comprising a PFPE chain;
• with the proviso that
• * in copolymer (PO-O)
• said block (1), said block (2), and, when present, said at least one block (3) are statistically distributed,
• the sum of (L+L{circumflex over ( )}) is at least 1;
• the total number of blocks (2) is from 1 to 100;
• wherein
• chain (Rf) comprises repeating units R°, said repeating units being independently selected from the group consisting of:
• (i) —CFXO—, wherein X is —F or —CF3;
• (ii) —CFXCFXO—, wherein X, equal or different at each occurrence, is —F or —CF3, with the proviso that at least one of X is —F:
• (v) —(CF2)j—CFZ—O— wherein j is an integer from 0 to 3 and Z is a group of general formula —O—R(f-a)—T, wherein R(f-a) is a fluoropolyoxyalkene chain comprising a number of repeating units from 0 to 10, said recurring units being chosen among the following:
• —CFXO—, —CF2CFXO—, —CF2CF2CF2O—, —CF2CF2CF2CF2O—, with each of X being independently —F or —CF3 and T being a C1-C3 perfluoroalkyl alkyl chain.

A block copolymer, copolymer (PF-O-O), comprising a first and a second perfluoropolyether chain, PFPE chain, wherein each of said first and second PFPE chain is a chain (Rf) or is a chain (RfO-O) wherein (RfO-O) is a repeating units complying with any one of formulae (i) to (v) for (R°) and having a peroxidic content (PO), defined as grams of active oxygen (Mw=16) in 100 g of PFPE peroxy between 0.1 and 4, each of said first and second PFPE chain having two chain ends, wherein the first chain end of each one of said first and second PFPE chain is a chain end of copolymer (P) and each one comprises a group selected from a perfluorinated linear or branched alkyl chain comprising from 1 to 6 carbon atoms, —COOH and salts thereof with an organic cation, or an inorganic cation;

• —COOR with R being a linear or branched alkyl chain comprising from 1 to 6 carbon atoms;
• —COF;
• —CON(R300)(R301) wherein each of R300 and R301 are a hydrogen atom or have the same meanings defined for R;
• —(R)cOH with c being 0 or 1 and R being a linear or branched alkyl chain comprising from 1 to 6 carbon atoms;
• —C(O)—O—C(O)R with R being a linear or branched alkyl chain comprising from 1 to 6 carbon atoms;
• —Br;
• —CN2;
• and the second chain ends of said first and second PFPE chain are bonded to each other via:
• at least one first block, block (1), complying with formula (I)
• wherein
• L{circumflex over ( )} is an integer from 1 to 250;
• R100, R101, R102 and R103 are each independently selected from halogen atom;
• linear or branched alkyl chain comprising from 1 to 6 carbon atoms;
• —OR200 wherein R200 is a linear or branched perfluorinated chain comprising from 1 to 6 carbon atoms or a group of formula —CF2OR201 in which R201 is a perfluorinated alkyl chain comprising from 1 to 6 carbon atoms, optionally interrupted by one or more oxygen ether atoms;
• or one of R100 and R101 and one of R102 and R103 are a fluorine atom and the other of R100 and R101 and the other of R102 and R103 together form a perhalogenated cyclic ring having from 4 to 6 members, optionally comprising heteroatoms;
• L is 0 or an integer from 1 to 250, and
• D is a group of formula —(CR100*R101*—CR102*R103*)— wherein at least one of R100*, R101* R102* and R103* is different from R100, R101, R102, and R103, such that (D) is different from —[CR100R101—CR102R103]L{circumflex over ( )};
• with the proviso that, when L{circumflex over ( )} and L are both different from 0, the recurring units are statistically distributed;
• at least one second block, block (2), complying with formula (II)
• wherein
• m is an integer from 1 to 5;
• R5 to R8, each independently, is selected
• from the group consisting of —F, perfluorinated linear or branched alkyl chain having from 1 to 6 carbon atoms, and group of formula (III):
• wherein
• R20 is a sigma bond, or linear or branched perfluoroalkyl chain comprising from 1 to 12 carbon atoms, optionally comprising and/or interrupted by at least one oxygen atom,
• X is a functional group;
• and
• y is an integer equal to 1 or 2;
• with the proviso that in formula (II), at least one, of R5 to R8 is group of formula (III);
• and
• optionally, at least one third block, block (3), comprising a PFPE chain;
• with the proviso that
• * in copolymer (PF-O-O)
• said block (1), said block (2), and, when present, said at least one block (3) are statistically distributed,
• the sum of (L+L{circumflex over ( )}) is at least 1;
• the total number of blocks (2) is from 1 to 100;
• wherein
• chain (Rf) comprises repeating units R°, said repeating units being independently selected from the group consisting of:
• (x) —CFXO—, wherein X is —F or —CF3;
• (xi) —CFXCFXO—, wherein X, equal or different at each occurrence, is —F or —CF3, with the proviso that at least one of X is —F:
• —(CF2)j—CFZ—O— wherein j is an integer from 0 to 3 and Z is a group of general formula —O— Rf-a)—T, wherein R(f-a) is a fluoropolyoxyalkene chain comprising a number of repeating units from 0 to 10, said recurring units being chosen among the following:
• —CFXO—, —CF2CFXO—, —CF2CF2CF2O—, —CF2CF2CF2CF2O—, with each of X being independently —F or —CF3 and T being a C1-C3 perfluoroalkyl alkyl chain.