Perfluoropolyether polymers

Abstract

The present invention relates to novel copolymers comprising (per) fluoropolyether chains and functional groups.

Description

[0001] Cross-references to related patent applications

[0002] This patent application claims priority from patent Nr 22198267.1 filed in Europe on September 28, 2022, the entire contents of which are incorporated by reference into this application for all purposes. Technical Field

[0003] The present invention relates to novel copolymers comprising (per)fluoropolyether chains and functional groups. Background Art

[0004] (Per)fluoropolyether polymers (hereinafter referred to as "PFPE polymers") have long been known as base oils or additives in several lubricant applications.

[0005] The synthesis of several PFPE polymers has been disclosed in the art. The first synthesis of an unspecified perfluorinated polyether mixture was reported in 1953, when an oily product was obtained during the photoligomerization of hexafluoropropylene. Since then, a variety of different perfluorinated polyethers have been synthesized and described in the literature.

[0006] US 4,500,739 (in the name of Montedison) discloses the reaction of peroxidized PFPE, inter alia, with perfluorobutadiene (class II of fluoroolefins). Example 4 discloses the reaction with perfluorobutadiene and a large excess of a perfluorinated diene to produce pendant unsaturated groups along the macromolecular chain, allowing the reaction to proceed further in the presence of hexamethylenediamine.

[0007] US 8,258,090 (in the name of Solvay Solexis SpA) discloses fluorinated lubricants having the formula:

[0008] (I) TO-[AB] z -[A'-B'] z’ -A-T'

[0009] in

[0010] T and T' are C 1-3 Perfluoroalkyl or C 1-6 alkyl,

[0011] A and A' are perfluoropolyether chains,

[0012] B is derived from two different olefins, at least one of which can be homopolymerized by a free radical route, and has the following formula:

[0013] (Ia) -[(CR1R2-CR3R4)j -(CR5R6-CR7R8) j’ ]-

[0014] in

[0015] j is from 1 to 5, j' is from 0 to 4 and the sum of j+j' is between 2 and 5;

[0016] R1 to R8 are halogen, H, C 1-6 (Per)halogenated alkyl, C 1-6 Alkyl, C 1-6 Oxy(per)fluoroalkyl;

[0017] z is greater than or equal to 2, z' is an integer and the sum of z and z' is such that the number average molecular weight of the polymer of formula (I) is in the range of 500 to 500 000;

[0018] B' is (Ia), but at least one of R1 to R8 has a meaning different from that in B.

[0019] This patent discloses block copolymers characterized by a linear main chain, without any branching. In fact, no branching is obtained in B, especially comprising (per)fluoropolyether chains.

[0020] PFPE polymers containing functional groups along the backbone have been disclosed in the art and are useful as reactive intermediate compounds and additives.

[0021] Perfluoropolyether polymers obtained by reacting polyperoxyperfluoropolyethers and fluorinated olefins in the presence of UV radiation have been disclosed in US Pat. No. 4,500,739 (Montedison SpA, Feb. 19, 1985).

[0022] US 6,403,539 (Ausimont SpA, June 11, 2002) discloses perfluoropolyether polymers containing sulfonyl fluoride groups as pendant groups along the main chain. This patent application discloses a process in which a sulfonyl fluoride-containing monomer is fed simultaneously with an O2 flow in a liquid reaction medium, thereby obtaining a perfluoropolyether containing peroxy groups in the chain. However, for safety reasons, the presence of peroxy groups is undesirable. Therefore, this patent application discloses that in order to obtain a non-peroxidized product without chain scission, the peroxidized perfluoropolyether is subjected to a thermal treatment at a temperature generally in the range of 150° C. to 250° C. or to a photochemical treatment, optionally in the presence of a solvent. The process disclosed herein, in which the functionalized monomer is added at the beginning of the polymerization, does not allow the synthesis of polymers having blocks separated from the functionalized monomer, but rather allows the synthesis of PFPE polymers having randomly distributed functional groups.

[0023] Multifunctional (per)fluoropolyether polymers are further disclosed in US Pat. No. 5,719,259 (EI DuPont deNemours and Company, February 17, 1998), US Pat. No. 4,853,097 (Oselmont Company, August 1, 1989), and US Pat. No. 5,104,911 (Oselmont Company, April 14, 1992).

[0024] US2011 / 0230631 (Solvay Solexis SpA, September 22, 2011) discloses (per)fluoropolyethers comprising at least one (per)fluoropolyoxyalkylene chain comprising at least one repeating unit having the formula -CF2-CF(CF2O-SO2F)-O-, wherein the fluorosulfate groups within brackets are pendant groups, which subsequently react with nucleophiles to provide functional groups, such as notably carboxylic acids, acyl fluorides, amides and esters.

[0025] CN 103724559 (ZHONGHAO CHENGUANG RES INST CHEMICALIND, April 16, 2014) discloses a method, which comprises placing a perfluoropolyether peroxide prepared by a photooxidation method in an inert fluorine-containing solvent, introducing a perfluoroolefin under ultraviolet irradiation conditions, and reacting the perfluoroolefin with the peroxide to form a stable perfluoropolyether compound.

[0026] WO 2019 / 048394 (Solvay Specialty Polymers Italy SpA, March 14, 2019) discloses multifunctional perfluoropolyether derivatives comprising a plurality of ionizable groups selected from the group consisting of -SO3Xa, -PO3Xa and -COOXa, wherein Xa is H, an ammonium group or a monovalent metal. Summary of the invention

[0027] The problem faced by the Applicant was to provide new functional PFPE copolymers characterized by increased viscosity (as measured by complex viscosity at 0.1 rad / s and 25° C.) while maintaining a low glass transition temperature (Tg) and remaining liquid at room temperature.

[0028] Furthermore, the new functional PFPE copolymers according to the invention are characterized by an increased viscosity index, notably between 40 and 100°C.

[0029] Furthermore and more unexpectedly, the new functional PFPE copolymers according to the present invention are characterized by increased thermal stability (as shown in the examples by TGA analysis), which makes them suitable for use in harsh environments and applications.

[0030] In addition, the new PFPE copolymers containing functional groups are suitable for use as additives in different technical fields (including rust prevention, wear resistance) to increase the compatibility between base oils and thickeners and other ingredients dispersed in such base oils. In addition, as will be explained in more detail in the detailed description, the functional groups can be further reacted or derivatized to provide further functionalized derivatives. DETAILED DESCRIPTION

[0031] For purposes of this specification and the following claims:

[0032] - the use of parentheses around an identifying symbol or number, for example in expressions like "polymer (P)" etc., has the sole purpose of making this symbol or number better distinguishable from the rest of the text, and therefore said parentheses may also be omitted;

[0033] - the acronym "PFPE" stands for "perfluoropolyether" and when used as a noun, is intended to refer to the singular or plural form, depending on the context;

[0034] - The term "functionality (F)" is intended to indicate the amount of functional groups in the copolymer according to the invention as measured by NMR or titration.

[0035] In a first aspect, the present invention relates to a block copolymer [copolymer (P)] comprising a first and a second perfluoropolyether chain [PFPE chain] each having two chain ends, wherein the first chain end of each of the first and second PFPE chains is a chain end of the copolymer (P) and each chain end comprises a group selected from a perfluorinated linear or branched alkyl chain containing from 1 to 6 carbon atoms, -C(=O)F and -OC(=O)F, and the second chain ends of the first and second PFPE chains are bonded to each other via:

[0036] - at least one first block [block (1)] conforming to formula (I):

[0037]

[0038] in

[0039] m is 0 or an integer from 1 to 5, preferably from 1 to 2;

[0040] R5 to R8 are each independently selected from the group comprising, preferably consisting of: -F, a perfluorinated linear or branched alkyl chain having from 1 to 6 carbon atoms, and a group having formula (II):

[0041] (II)-R 20 -(X) y

[0042] in

[0043] R 20 is a sigma bond, or a linear or branched perfluoroalkyl chain containing from 1 to 12 carbon atoms, which preferably contains and / or is interrupted by at least one oxygen atom,

[0044] X is a functional group, which is preferably selected from: -SO2F, -SO3H, -COOH, -COF, -CN, -Br and -CONH2; and

[0045] y is an integer equal to 1 or 2;

[0046] The prerequisite is that in formula (I), at least one, preferably one, of R5 to R8 is a group having formula (II);

[0047] - at least one second block [block (2)] conforming to formula (III):

[0048]

[0049] in

[0050] n is an integer from 1 to 3;

[0051] R1 to R4 are each independently selected from the group comprising, preferably consisting of: a fluorine atom, a perfluorinated linear or branched alkyl group having from 1 to 6 carbon atoms, a group having formula (IV):

[0052] (IV)-(R 10 ) t [C(R 11 )(R 12 )-C(R 13 )(R 14 )(R 15 )] z

[0053] in

[0054] R 10 is an oxygen atom, or a divalent / trivalent / tetravalent perfluorinated alkyl chain containing from 1 to 24 carbon atoms and optionally interrupted by at least one oxygen atom,

[0055] t is zero or 1,

[0056] z is an integer from 1 to 3,

[0057] R 11 To R 15 Each is independently selected from the group comprising, preferably consisting of, a fluorine atom, a perfluorinated linear or branched alkyl group having from 1 to 6 carbon atoms, and a group having formula (V):

[0058] -[(A) a -(B) b -(F) f ] u -(A)-T(V)

[0059] in

[0060] u is zero or an integer from 1 to 50;

[0061] T is a perfluorinated alkyl group;

[0062] a is zero or 1,

[0063] Each A is a PFPE chain;

[0064] b is zero or an integer from 1 to 3,

[0065] B is a block having formula (III*):

[0066] -[C(R 1^ )(R 2^ )-C(R 3^ )(R 4^ )]-(III*)

[0067] in

[0068] R 1^ To R 4^ Each independently has the meaning defined above for each of R1 to R4;

[0069] f is 0 or an integer from 1 to 5, preferably from 1 to 2;

[0070] F is a block having formula (I*):

[0071] -[C(R 5^ )(R 6^ )-C(R 7^ )(R 8^ )]-

[0072] in

[0073] R 5^ To R 8^each independently has the meaning provided above for each of R5 to R8 respectively;

[0074] The premise is:

[0075] - In the formula (III), at least one of R1 to R4 is a group having the formula (IV),

[0076] - In the formula (III*), R 1^ To R 4^ At least one of them is a group having formula (IV)

[0077] - In the formula (IV), R 11 or R 12 One of the 13 To R 15 One of the groups is a group having the formula (V),

[0078] - In said formula (V), the repeating units (A), (B) and (F) are statistically distributed;

[0079] as well as

[0080] - optionally, at least one third block comprising PFPE chains [block (3)];

[0081] The premise is that in the copolymer (P):

[0082] - the sum of (m+f) is at least 1, preferably from 1 to 100;

[0083] - the sum of (n+b) is at least 1, preferably from 1 to 15, more preferably from 1 to 11, even more preferably from 1 to 9; and

[0084] - the at least one block (1), the at least one block (2), and, when present, the at least one block (3) are statistically distributed.

[0085] It will be understood by a person skilled in the art that said first chain ends of said first and second PFPE chains correspond to the two chain ends of copolymer (P).

[0086] Preferably, in copolymer (P), each of said PFPE chains is a perfluorinated chain comprising, preferably consisting of, repeating units R° [chain (R f )], the repeating units are independently selected from the group consisting of:

[0087] (i) -CFXO-, wherein X is -F or -CF3;

[0088] (ii) -CFXCFXO-, where X is the same or different at each occurrence and is -F or -CF3, provided that at least one of X is -F;

[0089] (iii) -CF2CF2CF2O-;

[0090] (iv) -CF2CF2CF2CF2O-;

[0091] (v)-(CF2) j -CFZ-O-, wherein j is an integer from 0 to 3 and Z is a molecule having the general formula -OR (f-a) -T group, where R (f-a) is a fluoropolyoxyalkylene chain containing from 0 to 10 repeating units, the repeating units being selected from: -CFXO-, -CF2CFXO-, -CF2CF2CF2O-, -CF2CF2CF2CF2O-, wherein each X is independently -F or -CF3 and T is a C1-C3 perfluoroalkyl chain.

[0092] Preferably, the chain (R f ) conforms to the following formula:

[0093] (R f -I)

[0094] -[(CFX 1 O) g1 (CFX 2 CFX 3 O) g2 (CF2CF2CF2O) g3 (CF2CF2CF2CF2O) g4 ]-

[0095] in

[0096] -X 1 independently selected from -F and -CF3,

[0097] -X 2 , X 3 , which are the same or different from each other and, at each occurrence, are independently -F, -CF3, provided that at least one of X is -F;

[0098] - g1, g2, g3 and g4, identical or different from each other, are independently integers ≥ 0, such that g1+g2+g3+g4 is in the range of from 2 to 300, preferably from 2 to 100; if at least two of g1, g2, g3 and g4 are not zero, the different repeating units are generally statistically distributed along the chain.

[0099] More preferably, the chain (R f) is selected from chains having the formula:

[0100] (R f -IIA)-[(CF2CF2O) a1 (CF2O) a2 ]-

[0101] in:

[0102] a1 and a2 are independently integers ≥ 0, such that the number average molecular weight as measured by NMR is between 400 and 100,000, preferably between 400 and 50,000; both a1 and a2 are preferably not zero, wherein the ratio a1 / a2 is preferably comprised between 0.1 and 10;

[0103] (R f -IIB)-[(CF2CF2O) b1 (CF2O) b2 (CF(CF3)O) b3 (CF2CF(CF3)O) b4 ]-

[0104] in:

[0105] b1, b2, b3, b4 are independently integers ≥ 0, such that the number average molecular weight as measured by NMR is between 400 and 100,000, preferably between 400 and 50,000; preferably, each of b1, b2, b3, b4> 0;

[0106] (R f -IIC)-[(CF2CF2O) c1 (CF2O) c2 (CF2(CF2) cw CF2O) c3 ]-

[0107] in:

[0108] cw=1 or 2;

[0109] c1, c2 and c3 are independently integers ≥ 0, which are selected so that the number average molecular weight as measured by NMR is between 400 and 100,000, preferably between 400 and 50,000; preferably, c1, c2 and c3 are all > 0, wherein the ratio c3 / (c1+c2) is generally less than 0.2.

[0110] Still more preferably, the chain (R f ) conforms to the following formula (R f -III):

[0111] (R f-III)-[(CF2CF2O) a1 (CF2O) a2 ]-

[0112] in:

[0113] a1 and a2 are integers > 0 such that the number average molecular weight as measured by NMR is between 400 and 100,000, preferably between 400 and 50,000, wherein the ratio a1 / a2 is generally between 0.1 and 10, more preferably between 0.2 and 5.

[0114] Preferably, in block (1), m is 0 or an integer from 1 to 2.

[0115] Preferably, in block (1), one of R5 to R8 is a group having formula (II).

[0116] Preferably, in block (1), R 20 is a σ bond or is selected from the group consisting of: 20 -i) to (R 20 -iv) of the group:

[0117] (R 20 -i)

[0118] -(CF2) s1 -O-(CF2) s2 -

[0119] wherein each of s1 and s2 is independently an integer from 1 to 6, preferably from 1 to 3;

[0120] (R 20 -ii)

[0121] -O-(CF2) s3 -

[0122] wherein s3 is an integer from 1 to 6, preferably from 1 to 5;

[0123] (R 20 -iii)

[0124] -OR 400 -OR 401 -

[0125] in

[0126] R 400 is a linear or branched perfluorinated alkyl chain containing from 1 to 6, preferably from 1 to 3 carbon atoms, and more preferably conforms to the formula -CF2-, -CF2CF2-, -CF2CF2CF2-, -CF2CF(CF3)-; and

[0127] R401 is a linear or branched perfluorinated alkyl chain containing from 1 to 3 carbon atoms, more preferably conforming to the formula -CF2-, -CF2CF2-, -CF(CF2)-;

[0128] (R 20 -iv)

[0129]

[0130] in

[0131] R 500 is a linear perfluorinated alkyl chain containing from 1 to 6 carbon atoms, preferably from 1 to 3 carbon atoms and optionally interrupted by at least one oxygen atom;

[0132] R 501 Is a -OR 503 The chain, where R 503 is a linear perfluorinated alkyl chain containing from 1 to 3 carbon atoms;

[0133] R 502 is a linear perfluorinated alkyl chain containing from 1 to 4 carbon atoms and optionally interrupted by at least one oxygen atom;

[0134] R 501 and R 502 Each of which is combined with a group X as defined above in formula (II).

[0135] Preferably, in block (2) and formula (IV), R 10 Meets one of the following formulas:

[0136] (R 10 -i)-(CF2) d (O) e (CF2O) f R CF (O) e* (CF2) d* (CF2O) f*

[0137] in

[0138] Each of d, d*, e, e*, f, and f* is independently zero or 1, and

[0139] R CF is a perfluoroalkyl chain containing from 1 to 12, preferably from 1 to 8, carbon atoms, optionally interrupted by one or more oxygen atoms

[0140] (R 10 -ii)-O-(C3F6O) h –(CF2)i -(C3F6O) j -O-

[0141] Where h=j and h+j is from 2 to 6, and i is from 2 to 6.

[0142] In a second aspect, the present invention relates to a process for the manufacture of a copolymer (P) as defined above [process (P)].The process according to the present invention can be easily scaled up from laboratory scale to pilot and industrial scale.

[0143] Advantageously, the copolymer (P) of the present invention is prepared by a process (P) comprising at least the following steps:

[0144] (a) bringing into contact:

[0145] - at least one perfluoropolyether polymer [PFPE peroxide] comprising at least one peroxy group;

[0146] - at least one perfluorinated compound of formula (Xp):

[0147]

[0148] in

[0149] R 21 To R 23 Each of is independently -F, or a perfluorinated linear or branched alkyl chain having from 1 to 6 carbon atoms,

[0150] R 20 , X and y are as defined above for formula (II);

[0151] - at least one perfluorinated compound of formula (XX-p):

[0152]

[0153] in

[0154] R 21 To R 23 Each of which is as defined above in formula (Xp),

[0155] R 31 To R 33 Each of is independently -F, or a perfluorinated alkyl group having from 1 to 6 carbon atoms,

[0156] R 10 is an oxygen atom, a perfluorinated alkyl chain containing from 1 to 24 carbon atoms, optionally interrupted by at least one oxygen atom,

[0157] t is zero or 1;

[0158] Each of z* and z** is independently 1 or 2; and

[0159] (b) reacting the PFPE peroxide, the at least one compound of formula (Xp) and the at least one compound of formula (XX-p) in the presence of UV radiation or under heating.

[0160] In step (a), the order of addition of the reactants is not limited. Thus, the PFPE peroxide, the compound of formula (Xp) and the compound of formula (XX-p) can be supplied to the reaction environment in any order.

[0161] Prior to step (a), the PFPE peroxide may have been subjected to partial reduction of the peroxy bonds, for example by chemical reduction or UV treatment or thermal treatment.

[0162] Preferably, the PFPE peroxide is a peroxidized perfluoropolyether polymer having two chain ends, each chain end comprising a group selected from a linear or branched perfluorinated alkyl chain containing from 1 to 6 carbon atoms or -C(=O)F, the two chain ends being bonded to a perfluoropolyether chain [chain (R f )], the perfluoropolyether chain comprises, preferably consists of, repeating units (R°) independently chosen from the group consisting of formulae (i) to (v) as defined above and having a peroxide content (PO) defined as the grams of active oxygen (Mw=16) in 100 g of PFPE peroxide, between 0.1 and 4, preferably between 0.1 and 3.5.

[0163] Preferably, in the PFPE peroxide, the chain (R f ) conforms to formula (Rf-I), or (Rf-IIA), (Rf-IIB), (Rf-IIC) or (Rf-III) as defined above.

[0164] Preferably, in the at least one compound having formula (Xp), R 21 , R 22 and R 23 Each of them is -F.

[0165] Preferably, in the compound (Xp), R 20 is a sigma bond or is selected from the group consisting of 20 -i) to (R 20 -iv) of the group:

[0166] (R 20 -i)

[0167] -(CF2)s1 -O-(CF2) s2 -

[0168] wherein each of s1 and s2 is independently an integer from 1 to 6, preferably from 1 to 3;

[0169] (R 20 -ii)

[0170] -O-(CF2) s3 -

[0171] wherein s3 is an integer from 1 to 6, preferably from 1 to 5;

[0172] (R 20 -iii)

[0173] -OR 400 -OR 401 -

[0174] in

[0175] R 400 is a linear or branched perfluorinated alkyl chain containing from 1 to 6, preferably from 1 to 3 carbon atoms, and more preferably conforms to the formula -CF2-, -CF2CF2-, -CF2CF2CF2-, -CF2CF(CF3)-; and

[0176] R401 is a linear or branched perfluorinated alkyl chain containing from 1 to 3 carbon atoms, more preferably conforming to the formula -CF2-, -CF2CF2-, -CF(CF2)-;

[0177] (R 20 -iv)

[0178]

[0179] in

[0180] R 500 is a linear perfluorinated alkyl chain containing from 1 to 6 carbon atoms, preferably from 1 to 3 carbon atoms and optionally interrupted by at least one oxygen atom;

[0181] R 501 Is a -OR 503 The chain, where R 503 is a linear perfluorinated alkyl chain containing from 1 to 3 carbon atoms;

[0182] R 502 is a linear perfluorinated alkyl chain containing from 1 to 4 carbon atoms and optionally interrupted by at least one oxygen atom;

[0183] R 501 and R502 Each of which is combined with a group X as defined above.

[0184] Preferably, the at least one compound of formula (Xp) is selected from the group comprising, more preferably consisting of:

[0185] CF2=CFCF2OCF2CF2COOH

[0186] CF2=CFOCF2COOH

[0187] CF2=CFO(CF2)5COOH

[0188] CF2=CFOCF2CF2OCF2COOH

[0189] CF2=CFOCF2CF2COOH

[0190] CF2=CFCF2OCF2CF2COF

[0191] CF2=CFOCF2COF

[0192] CF2=CFO(CF2)3OCF(CF3)COF

[0193] CF2=CFO(CF2)5COF

[0194] CF2=CFOCF2CF(CF3)OCF2CF2CN

[0195] CF2=CFOCF2CN

[0196] CF2=CFO(CF2)5CN

[0197] CF2=CFO(CF2)3OCF(CF3)CN

[0198] CF2=CFCF2OCF2CF2CN

[0199] CF2=CFOCF2CF2Br

[0200] CF2=CFCF2OCF2CF2Br

[0201] CF2=CFOCF2CF(CF3)OCF2CF2Br

[0202] CF2=CFCF2OCF2CF2CONH2

[0203] CF2=CFOCF2CONH2

[0204] CF2=CFOCF2CF2CONH2

[0205] CF2=CFOCF2CF2SO2F

[0206] CF2=CFSO2F

[0207] CF2=CFOCF2CF(SO2F)2

[0208] CF2=CFOCF2CF(CF2OCF2CF2SO2F)(OCF2CF2SO2F)

[0209] CF2=CFOCF2CF(CF2CF2SO2F)(OCF2CF2SO2F)

[0210] CF2=CFOCF2OCF2CF(CF2OCF2CF2SO2F)(SO2F).

[0211] Some exemplary compounds of formula (Xp) and their preparation are provided in WO 03 / 106515 (in the name of Daikin Ind.), JP 2017-025242 (in the name of ASAHI GLASS CO., LTD.), and US 2008 / 138685 (in the name of AGC Inc.).

[0212] Preferably, in the compound of formula (XX-p), when t is 1, one, two, three or four unsaturated moieties are bonded to 10 The residues are located on the same or different atoms of the residues, preferably on carbon atoms.

[0213] Preferably, the at least one compound having formula (XX-p) conforms to the following formula:

[0214] CF2=CF(R 10 ) t CF=CF2

[0215] where t is either zero or 1, and

[0216] R 10 Meets one of the following formulas:

[0217] (R 10 -i)-(CF2) d (O) e (CF2O) f R CF (O) e* (CF2) d* (CF2O) f*

[0218] in

[0219] Each of d, d*, e, e*, f, and f* is independently zero or 1, and

[0220] R CF is a perfluoroalkyl chain containing from 1 to 12, preferably from 1 to 8, carbon atoms, optionally interrupted by one or more oxygen atoms

[0221] (R 10 -ii)-O-(C3F6O) h –(CF2) i -(C3F6O) j -O-

[0222] Where h=j and h+j is from 2 to 6, and i is from 2 to 6.

[0223] According to a particularly preferred embodiment, the at least one compound having formula (XX-p) conforms to the following formula:

[0224] CF2=CF(R 10 ) t CF=CF2

[0225] where t is 1 and

[0226] R 10 Conforms to the following formula:

[0227] (R 10 -i)-(CF2) d (O) e (CF2O) f R CF (O) e* (CF2) d* (CF2O) f*

[0228] in

[0229] d, f, d* and f* are zero,

[0230] e and e* are 1, and

[0231] R CF is a linear perfluoroalkyl chain containing from 1 to 10, preferably from 1 to 8 carbon atoms.

[0232] Preferably, the compound of formula (XX-p) is selected from the group comprising, more preferably consisting of:

[0233] CF2=CFCF=CF2

[0234] CF2=CFOCF=CF2

[0235] CF2=CFCF2OCF2CF=CF2

[0236] CF2=CFO-(CF2)3CF=CF2

[0237] CF2=CFCF2O(CF2)3OCF2-CF=CF2

[0238] CF2=CFCF2CF=CF2

[0239] CF2=CF(CF2)2CF=CF2

[0240] CF2=CF(CF2)3CF=CF2

[0241] CF2=CF(CF2)4CF=CF2

[0242] CF2=CFOCF2OCF=CF2

[0243] CF2=CFO(CF2)2OCF=CF2

[0244] CF2=CFO(CF2)3OCF=CF2

[0245] CF2=CFO(CF2)4OCF=CF2

[0246] CF2=CF(CF2)2OCF=CF2

[0247] CF2=CF(CF2)3OCF=CF2

[0248] CF2=CF(CF2)4OCF=CF2

[0249] CF2=CFCF2O(CF2)2OCF2O-CF=CF2

[0250] CF2=CFCF2O(CF2)3OCF2O-CF=CF2

[0251] CF2=CFCF2O(CF2)4OCF2OCF=CF2

[0252] CF2=CFCF2O(CF2)6OCF2CF=CF2

[0253] CF2=CFO-CF2O-(CF2)2O-CF2O-CF=CF2

[0254] CF2=CFO-CF2O-(CF2)3O-CF2O-CF=CF2

[0255] CF2=CFO-CF2O-(CF2)4O-CF2O-CF=CF2

[0256] CF2=CFO-(CF2O)6-CF=CF2

[0257] CF2=CFO-(CF2CF2O)2-CF=CF2

[0258] CF2=CFO-(CF2CF2O)2-CF2OCF=CF2

[0259] CF2=CFO(C3F6O) h -(CF2) i -(C3F6O) j -OCF=CF2

[0260] where h and j are the same and

[0261] Their sum is from 2 to 6 and i is from 2 to 6.

[0262] The amount of each of the at least one compound (Xp) and compound (XX-p) is not limited.

[0263] For example, the equivalent of double bonds of the compound (Xp) to the equivalent of peroxy groups is preferably in the range of from 1:100 to 5000:100.

[0264] Likewise, the equivalents of double bonds of the compound (XX-p) to the equivalents of peroxy groups are preferably in the range from 1:100 to 100:100.

[0265] Step (a) of process (P) can advantageously be carried out by contacting the PFPE peroxide with a compound of formula (Xp).

[0266] Alternatively, the step (a) may be performed by contacting the PFPE peroxide with two or more compounds of formula (Xp).

[0267] Step (a) of process (P) can advantageously be carried out by contacting the PFPE peroxide with a compound of formula (XX-p).

[0268] Alternatively, the step (a) may be performed by contacting the PFPE peroxide with two or more compounds of formula (XX-p).

[0269] Step (a) and step (b) may be performed in the presence of a fluorinated solvent.

[0270] Preferably, the fluorinated solvent is selected in the group comprising: perfluorocarbons, hydrofluorocarbons, perfluoropolyethers, hydrofluoropolyethers.

[0271] Preferably, step (b) is carried out in the presence of UV radiation for a period of from 2 to 150 hours, more preferably from 5 to 100 hours.

[0272] Preferably, step (b) is carried out in the presence of UV radiation at a temperature from -60 to +150°C, more preferably from -20 to +100°C and even more preferably from 0 to 60°C.

[0273] As an alternative, step (b) may be carried out under thermal treatment, preferably by heating at a temperature of from 150°C to 250°C.

[0274] Preferably, the step (b) is carried out in an inert atmosphere.

[0275] Preferably, the method (P) comprises a solvent removal step (c) and / or a classification step (d) after step (b).

[0276] Said step (c) of removing the solvent may be carried out by evaporation, for example by vacuum distillation.

[0277] The fractionation step (d) can be carried out by solvent extraction. When the fractionation step is carried out by precipitation fractionation, supercritical CO2, hexafluoroxylene or hydrofluorocarbons and mixtures thereof are used as solvents. Supercritical CO2 is preferred.

[0278] In a third aspect, the present invention relates to a copolymer (P) obtainable by process (P) as described above.

[0279] Advantageously, the functional groups introduced as side groups in block (1) of the copolymer (P), such as notably -SO2F, -SO3H, -COOH, -COF, -CN, -Br and -CONH2, as well as the functional groups at the chain ends of the copolymer (P), such as notably -COF and -OC(O)F, can be appropriately reacted to obtain other different functional groups.

[0280] The expression “reactive” is intended to indicate that such functional groups can, for example, be salified, hydrolyzed, reduced, oxidized or undergo different chemical reactions to provide one or more functional groups with the desired reactivity, taking into account the final use of the copolymer (P).

[0281] Advantageously, the copolymers (P F ) is obtained from method (P) as described above, which further comprises at least one step (c) after step (b), which step comprises at least one of salification, hydrolysis, oxidation, reduction or another chemical reaction capable of providing one or more functional groups of interest.

[0282] The present invention further encompasses the copolymer (P) obtained at the end of step (c) of process (P) F ).

[0283] Thus, the present invention encompasses a block copolymer [copolymer (P F )] comprising a first and a second perfluoropolyether chain [PFPE chain] each having two chain ends, wherein the first chain end of each of the first and second PFPE chains is a chain end of the copolymer (P), and each chain end comprises a group selected from the group consisting of: a perfluorinated linear or branched alkyl chain containing from 1 to 6 carbon atoms; -COOH and its radicals with organic cations, preferably onium cations, more preferably ammonium, or with inorganic cations, preferably alkali metals, more preferably Na + , K + -COOR, wherein R is a linear or branched alkyl chain containing from 1 to 6 carbon atoms, preferably from 1 to 3 carbon atoms, more preferably 1 carbon atom; -COF; -CONH2; -CON(R 300 )(R 301 ), where R 300 and R 301 Each of these has the same meaning as defined for R; -(R) c OH, wherein c is 0 or 1, and R is as defined above; -C(O)-OC(O)R, wherein R is as defined above;

[0284] Provided that (i) at least one of the chain ends of the first and second PFPE chains comprises a group other than a perfluorinated linear or branched alkyl chain having from 1 to 6 carbon atoms; and (ii) when one chain end comprises the group -COF, the other chain end does not comprise a perfluorinated linear or branched alkyl chain having from 1 to 6 carbon atoms or -COF;

[0285] And the second chain ends of the first and second PFPE chains are bonded to each other via:

[0286] - at least one first block [block (1)] conforming to formula (I):

[0287]

[0288] in

[0289] m, R5 to R8 have the meanings defined above;

[0290] - at least one second block [block (2)] conforming to formula (III):

[0291]

[0292] in

[0293] n, R1 to R4 have the meanings defined above;

[0294] as well as

[0295] - optionally, at least one third block comprising PFPE chains [block (3)];

[0296] The premise is that in the copolymer (P F )middle:

[0297] - the sum of (m+f) is at least 1, preferably from 1 to 100;

[0298] - the sum of (n+b) is at least 1, preferably from 1 to 15, more preferably from 1 to 11, even more preferably from 1 to 9; and

[0299] - the at least one block (1), the at least one block (2), and, when present, the at least one block (3) are statistically distributed.

[0300] In another aspect, the present invention relates to a mixture [mixture (P F )], which comprises two or more copolymers as defined above (P F ).

[0301] Although a purification step may be performed after any of step (b) and / or step (c) of the process (P), the copolymer (P) or copolymer (P) according to the present invention is typically obtained. F ).

[0302] Therefore, in a further aspect, the present invention relates to a mixture [mixture (P)] comprising two or more copolymers (P) as defined above.

[0303] It will be clear to the skilled person that mixture (P) is obtained by process (P) as described above.

[0304] Advantageously, said mixture (P) may be subjected to one or more purification steps as disclosed above (also called "fractionation" steps), so as to obtain individual copolymers (P) characterized by different viscosities and / or as determined by 19 The number average molecular weight and / or functionality (F) measured by F-NMR is preferably from 3 to 102.

[0305] The mixture may further contain PFPE peroxides used as starting materials and / or copolymers (P) containing peroxide groups which may be obtained [copolymers (P O-O )] and / or a copolymer containing a peroxide group (P F )[Copolymer (P F-O-O)].

[0306] Advantageously, the copolymer (P O-O ) and / or copolymer (P F-O-O ) can be isolated and used as intermediates in other processes.

[0307] Although based on the amount of the starting peroxy groups in the PFPE peroxide, the amount of the starting peroxy groups in the PFPE peroxide may be present in the copolymer (P) or copolymer (P F ), can be up to 99%, but depending on the final application, the amount of peroxy groups can be appropriately adjusted, for example, to up to 95%, 90%, 85%, 80%, 75%, 70%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, 5%.

[0308] More preferably, the amount of peroxy groups is up to 1%, even more preferably up to 0.5%, and still more preferably up to 0.1%.

[0309] In another aspect, the present invention relates to a block copolymer [copolymer (P O-O )], comprising a first and a second perfluoropolyether chain [PFPE chain], wherein each of the first and second PFPE chains is a chain (Rf) as defined above or a chain (Rf O-O ), where (Rf O-O ) is a repeating unit conforming to any one of the formulae (i) to (v) as defined above for (R°) and having a peroxide content (PO) defined as grams of active oxygen (Mw=16) in 100 g of PFPE peroxide of between 0.1 and 4, preferably between 0.1 and 3.5, each of said first and second PFPE chains having two chain ends, wherein the first chain end of each of said first and second PFPE chains is a chain end of copolymer (P) and each chain end 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 chains are bonded to each other via:

[0310] - at least one first block according to formula (I) as defined above [block (1)];

[0311] - at least one second block conforming to formula (III) as defined above [block (2)];

[0312] and / or

[0313] - optionally, at least one third block comprising PFPE chains as defined above [block (3)];

[0314] The premise is

[0315] * In copolymer (P O-O )middle

[0316] - the block (1), the block (2), and, when present, the block (3) are statistically distributed,

[0317] – the sum of (n+b) is at least 1, preferably from 1 to 15, more preferably from 1 to 11, even more preferably from 1 to 9;

[0318] The sum of –(m+f) is at least 1, preferably from 1 to 100.

[0319] In yet another embodiment, the present invention relates to a block copolymer [copolymer (P F-O-O )], comprising a first and a second perfluoropolyether chain [PFPE chain], wherein each of the first and second PFPE chains is a chain (Rf) as defined above or a chain (Rf O-O ), where (Rf O-O ) is a repeating unit conforming to any one of the formulae (i) to (v) as defined above for (R°) and having a peroxide content (PO) defined as the grams of active oxygen (Mw=16) in 100 g of PFPE peroxide of between 0.1 and 4, preferably between 0.1 and 3.5, each of said first and second PFPE chains having two chain ends, wherein the first chain end of each of said first and second PFPE chains is a chain end of copolymer (P), and each chain end comprises a group selected from the group consisting of: a perfluorinated linear or branched alkyl chain comprising from 1 to 6 carbon atoms; -COOH and its radicals with organic cations, preferably onium cations, more preferably ammonium, or with inorganic cations, preferably alkali metals, more preferably Na + , K + -COOR, wherein R is as defined above; -COF; -CON(R 300 )(R 301 ), where R 300 and R 301 Each of is a hydrogen atom or has the same meaning as defined for R; -(R) c OH, wherein c is 0 or 1 and R is as defined above; -C(O)-OC(O)R, wherein R is as defined above; -Br; -CN2; and the second chain ends of the first and second PFPE chains are bonded to each other via:

[0320] - at least one first block according to formula (I) as defined above [block (1)];

[0321] - at least one second block conforming to formula (III) as defined above [block (2)];

[0322] and / or

[0323] - optionally, at least one third block comprising PFPE chains as defined above [block (3)];

[0324] The premise is

[0325] * In copolymer (P F-O-O )middle

[0326] - the block (1), the block (2), and, when present, the block (3) are statistically distributed,

[0327] – the sum of (n+b) is at least 1, preferably from 1 to 15, more preferably from 1 to 11, even more preferably from 1 to 9;

[0328] The sum of –(m+f) is at least 1, preferably from 1 to 100.

[0329] In yet another aspect, the present invention relates to a mixture [mixture (M1)] comprising at least one copolymer (P) as defined above and at least one of the PFPE peroxides and / or copolymers (P) used as starting materials. O-O )

[0330] In yet another aspect, the present invention relates to a mixture [mixture (M2)] comprising at least one copolymer as defined above (P F ), and at least one copolymer (P) as defined above, the PFPE peroxide used as starting material, the one or more copolymers (P O-O ) and / or the one or more copolymers (P F-O-O ).

[0331] The copolymer (P) and / or copolymer (P F ) can be used in different applications in several industries where excellent resistance and durability under high temperature and harsh environments are required. For example, copolymer (P) and / or copolymer (P F ) can be used as a base oil as a lubricant. Alternatively, copolymer (P) and / or copolymer (P F ) can be used as an additive in halogenated oils and / or greases.

[0332] To this end and advantageously, the copolymers according to the invention and the mixtures described herein are in the liquid state at room temperature, or even at temperatures below room temperature, which has advantages in terms of handling and storage of the copolymers.

[0333] Advantageously, therefore, the copolymer (P) is in the liquid state at room temperature.

[0334] Furthermore, advantageously, the copolymer (P F ) is in liquid state at room temperature.

[0335] In addition, the copolymer (P O-O ) and copolymers (P F-O-O ) and each of mixture (M1) and mixture (M2) are in liquid state at room temperature.

[0336] In addition, the copolymer (P O-O ) and copolymers (P F-O-O ) and each of mixture (M1) and mixture (M2) are in liquid state at room temperature.

[0337] Should the disclosure of any patents, patent applications, and publications incorporated by reference into this application conflict with the description of this application to the extent that a term may be unclear, this description shall take precedence.

[0338] The present invention will be explained in more detail hereinafter with the aid of the examples contained in the following experimental part; these examples are merely illustrative and are in no way to be construed as limiting the scope of the present invention.

[0339] Experimental Section

[0340] Material

[0341] Perfluoropolyether peroxide oil was obtained from Solvay Specialty Polymers Italy and conforms to the following formula

[0342] XO-(CF2CF2O) a1 (CF2O) a2 (O) h -X'

[0343] in

[0344] X and X' are -CF3, -CF2COF, -COF, and have the following properties:

[0345] Mn=31 990g / mol; PO=1.61%; a1 / a2=1.0

[0346] The following were purchased from Anles and are used as is:

[0347] (8CNVE)CF2=CFOCF2CF(CF3)OCF2CF2CN

[0348] (PBVE)CF2=CFOCF2CF2CF2OCF=CF2

[0349] The perfluorinated solvents Galden(R) HT200 and Galden(R) D100, as well as tetrafluoroethylene (TFE) and perfluoro-methylvinyl-ether (PMVE), and perfluorinated sulfonyl vinyl ether (VEFS) CF2=CFOCF2CF2SO2F were obtained through Solvay Specialty Polymers Italy.

[0350] method:

[0351] 19 F-NMR-Using 19 The structure, molecular weight, and chain end composition of the perfluoropolyether oil were obtained using a Varian Mercury 300MHz spectrometer operating with a F core. CFCl3 was used as an internal standard to obtain the 19 F-NMR spectrum.

[0352] The peroxide content (PO) is expressed as grams of peroxide oxygen per 100 g of polymer. The analysis of the peroxide content is carried out by iodometric titration using a Mettler DL40 apparatus equipped with a platinum electrode. The sensitivity limit for the PO determination is 0.0002%.

[0353] Complex viscosity was measured by frequency sweep testing using a MCR502 Anton-Paar rheometer with parallel plate geometry (25 mm diameter). The viscosity was measured in this way at 25°C and 100°C and its value at 0.1 rad / s oscillation is reported.

[0354] The viscosity index is calculated by measuring the viscosity at about 40°C and about 100°C according to ASTM D2270.

[0355] TGA analysis was performed with a TGA 5500 analyzer from TA Instruments in an oxygen-containing atmosphere (air) at a heating rate of 10° C. / min, measuring the temperatures at which the samples lost 10% and 50% of their weight.

[0356] FT-IR spectra were obtained on liquid samples (as thin films on KBr) using a Thermo Fisher IS10 spectrometer.

[0357] GPC analysis to measure average molecular weights (Mw and Mn) was performed on a Waters GPC equipped with an RI detector and operated at 35° C. All average molecular weight results are reported relative to a perfluoropolyether linear neutral internal standard.

[0358] Example 1 - PFPE Copolymer with 8CNVE, PBVE

[0359] 249.2 g of the peroxidized perfluoropolyether oil described above were charged into a 1500 mL stirred cylindrical photochemical reactor equipped with a high pressure mercury lamp model HANAU TQ150, a thermocouple, a condenser and a mechanical stirrer.

[0360] The oil was diluted with 1876 g of Galden (R) D100. Next, 19.4 g of 8CNVE and 2.5 g of PBVE were added to the reactor. The mixture was then purged with nitrogen under stirring and the UV lamp was turned on at 20° C. for 42 hours. After this time, the lamp was turned off and the reaction mixture was transferred to a 2-L round bottom flask. The mixture was stripped at 120° C. for 6 h under reduced pressure (0.1 mbar).

[0361] 265 g of a copolymer were obtained as a residue in the form of a transparent viscous oil.

[0362] 19 F-NMR analysis confirmed that the incorporation concentration of 8CNVE in the copolymer was 8.1 wt%.

[0363] The copolymer has a2 / a1=0.9, and X and X'=-CF3, -CF2COF and -OCOF.

[0364] The introduction of the -CN functional group was also confirmed by FT-IR spectroscopy, confirming the presence of a -CN functional group at 2269 cm -1 The existence of the peak at.

[0365] Comparative Example 1 - PFPE Copolymer with 8CNVE

[0366] 252.1 g of the peroxidized perfluoropolyether oil described above was charged into the same reactor as in Example 1. The oil was diluted with 1873 g of Galden(R) HT200. Next, 19.45 g of 8CNVE was added to the reactor and the mixture was purged with nitrogen. The mixture was then purged with nitrogen while stirring and the UV lamp was turned on at 20°C for 41 hours.

[0367] After this time, the light was turned off and the reaction mixture was transferred to a 2-L round bottom flask.The mixture was stripped under reduced pressure (0.1 mbar) at 120°C for 6 h.

[0368] 224.5 g of a copolymer were obtained as a residue in the form of a transparent viscous oil.

[0369] Product 19 F-NMR analysis confirmed the following copolymer structure, in which the concentration of 8CNVE was 8.0 wt %:

[0370] XO-(CF2CF2O) a2 (CF2O)a1 (CF2CFO(CF2CF(CF3)OCF2CF2CN)) m -X'

[0371] Where a2 / a1=0.9,

[0372] m=6.4

[0373] X and X' = -CF3, -CF2COF and -OCOF.

[0374] Number average molecular weight (M n )=31100g / mol.

[0375] The introduction of the -CN functional group was also confirmed by FT-IR spectroscopy, confirming the presence of a -CN functional group at 2269 cm -1 The existence of the peak at.

[0376] Example 2 - PFPE Copolymer with VEFS and PBVE

[0377] 250.5 g of the peroxidized perfluoropolyether oil described above was charged into the same reactor as in Example 1. The oil was diluted with 1877 g of Galden (R) HT200. Next, 14.0 g of VEFS and 2.5 g of PBVE were added to the reactor and the mixture was purged with nitrogen. The UV lamp was then turned on and the reaction was carried out at 20° C. for 7 h. After this period of time, the UV lamp was turned off.

[0378] The solution obtained was distilled in a round-bottom flask equipped with a magnetic stirrer at 240° C. for 4 h in order to remove the solvent and unreacted traces of monomers. The distillation was first carried out at atmospheric pressure and then at reduced pressure (0.1 mbar) until the solvent was completely removed.

[0379] 220.3 g of a copolymer were obtained as a residue in the form of a transparent viscous oil.

[0380] 19 F-NMR analysis confirmed the absence of residual peroxide units and the incorporation concentration of VEFS in the copolymer was 5.8 wt%.

[0381] The copolymer has a2 / a1=1.0, and X and X'=-CF3, -CF2COF and -OCOF.

[0382] Comparative Example 2a - PFPE Copolymer with VEFS

[0383] 250 g of the peroxidized perfluoropolyether oil described above was charged into the same reactor as in Example 1. The oil was diluted with 1875 g of Galden(R) HT200. Next, 14.0 g of VEFS was added to the reactor and the mixture was purged with nitrogen. The UV lamp was then turned on and the reaction was carried out at 20° C. for 7 h. After this time, the UV lamp was turned off.

[0384] The solution obtained was distilled in a round-bottom flask equipped with a magnetic stirrer at 240° C. for 4 h in order to remove the solvent and unreacted traces of monomers. The distillation was first carried out at atmospheric pressure and then at reduced pressure (0.1 mbar) until the solvent was completely removed.

[0385] 215.9 g of a copolymer were obtained as a residue in the form of a transparent oil.

[0386] Product 19 F-NMR analysis confirmed the absence of residual peroxide, the incorporation concentration of VEFS at 6.0 wt % and the following structure:

[0387] XO-(CF2CF2O) a2 (CF2O) a2 (CF2CFO(CF2CF2SO2F)) m -X'

[0388] in

[0389] a2 / a1=1.0,

[0390] Average m = 5.6

[0391] X and X' = -CF3, -CF2COF and -OCOF; and

[0392] Number average molecular weight (Mn) = 30400 g / mol.

[0393] Comparative Example 2b - PFPE Copolymer with VEFS, TFE, PMVE and PBVE

[0394] 250.3 g of the peroxidized perfluoropolyether oil described above were charged into a 1500 mL stirred cylindrical photochemical reactor equipped with a high pressure mercury lamp model HANAU TQ150, a thermocouple, a condenser and a mechanical stirrer.

[0395] The oil was diluted with 1876 g of Galden(R) HT200, and then 23.0 g of VEFS and 1.1 g of PBVE were added to the reactor.

[0396] The mixture was then purged with nitrogen under stirring, after which two fluorinated olefins PMVE and TFE were introduced into the reactor at a rate of 14.6 and 8.0 g / h, respectively. After the flow began, the UV lamp was turned on and the reaction was carried out at 20° C. for 7 h. After this period of time, the olefin flow was interrupted and the UV lamp was turned off.

[0397] The solution obtained was distilled in a round-bottom flask equipped with a magnetic stirrer at 240° C. for 4 h in order to remove the solvent and unreacted traces of monomers. The distillation was first carried out at atmospheric pressure and then at reduced pressure (0.1 mbar) until the solvent was completely removed.

[0398] 298.0 g of copolymer are obtained as residue in the form of a clear viscous oil, which is analyzed by iodine titration to confirm complete removal of the peroxide units.

[0399] 19 F-NMR analysis confirmed the absence of residual peroxide units.

[0400] The incorporation concentrations of VEFS, TFE and MVE in the copolymer are 5.3, 13.9 and 9.8 wt %, respectively.

[0401] The copolymer has a1 / a2=0.9, and X and X'=-CF3, -CF2COF and -OCOF.

[0402] The properties of the copolymers according to the invention and comparative copolymers are summarized in Table 1 below.

[0403] Table 1

[0404]

[0405] (*)contrast

[0406] n / p = not carried out

[0407] The polymers of Example 2 and Comparative Example 2a were also subjected to TGA analysis to measure their weight loss under heating conditions. The results are reported in Table 2 below.

[0408] Table 2

[0409] Loss of 10% by weight 50% weight loss Example 2 430℃ 522℃ Comparison 2a(*) 396℃ 503℃

[0410] (*)contrast

Claims

1. A block copolymer [copolymer (P)] comprising a first and a second perfluoropolyether chain [PFPE chain] each having two chain ends, wherein the first chain end of each of the first and second PFPE chains is a chain end of the copolymer (P) and each chain end comprises a group selected from a perfluorinated linear or branched alkyl chain containing from 1 to 6 carbon atoms, -C(=O)F and -OC(=O)F, and the second chain ends of the first and second PFPE chains are bonded to each other via: - at least one first block [block (1)] conforming to formula (I): in m is 0 or an integer from 1 to 5; R5 to R8 are each independently selected from the group consisting of: -F, a perfluorinated linear or branched alkyl chain having from 1 to 6 carbon atoms, and a group having formula (II): (II)-R 20 -(X) y in R 20 is a sigma bond, or a linear or branched perfluoroalkyl chain containing from 1 to 12 carbon atoms, which preferably contains and / or is interrupted by at least one oxygen atom, X is a functional group, which is preferably selected from: -SO2F, -SO3H, -COOH, -COF, -CN, -Br and -CONH2; and y is an integer equal to 1 or 2; The prerequisite is that in formula (I), at least one, preferably one, of R5 to R8 is a group having formula (II); - at least one second block [block (2)] conforming to formula (III): (III) in n is an integer from 1 to 3; R1 to R4 are each independently selected from the group comprising: a fluorine atom, a perfluorinated linear or branched alkyl group having from 1 to 6 carbon atoms, a group having formula (IV): (IV)-(R 10 ) t [C(R 11 )(R 12 )-C(R 13 )(R 14 )(R 15 )] z in R 10 is an oxygen atom, or a divalent / trivalent / tetravalent perfluorinated alkyl chain containing from 1 to 24 carbon atoms and optionally interrupted by at least one oxygen atom, t is zero or 1, z is an integer from 1 to 3, R 11 To R 15 Each is independently selected from the group comprising: a fluorine atom, a perfluorinated linear or branched alkyl group having from 1 to 6 carbon atoms, and a group having formula (V): -[(A) a -(B) b -(F) f ] u -(A)-T (V) in u is zero or an integer from 1 to 50; T is a perfluorinated alkyl group; a is zero or 1, Each A is a PFPE chain; b is zero or an integer from 1 to 3, B is a block having formula (III*): -[C(R 1^ )(R 2^ )-C(R 3^ )(R 4^ )]- (III*) in R 1^ To R 4^ Each independently has the meaning defined above for each of R1 to R4; f is 0 or an integer from 1 to 5; F is a block having formula (I*): -[C(R 5^ )(R 6^ )-C(R 7^ )(R 8^ )]- in R 5^ To R 8^ each independently has the meaning provided above for each of R5 to R8 respectively; The premise is: - In the formula (III), at least one of R1 to R4 is a group having the formula (IV), - In the formula (III*), R 1^ To R 4^ At least one of them is a group having formula (IV) - In the formula (IV), R 11 or R 12 One of the 13 To R 15 One of the groups is a group having the formula (V), - In said formula (V), the repeating units (A), (B) and (F) are statistically distributed; as well as - optionally, at least one third block comprising PFPE chains [block (3)]; The premise is that in the copolymer (P): - the sum of (m+f) is at least 1, preferably from 1 to 100; - the sum of (n+b) is at least 1, preferably from 1 to 15; and - the at least one block (1), the at least one block (2), and, when present, the at least one block (3) are statistically distributed.

2. The copolymer (P) according to claim 1, wherein Each of the PFPE chains is a perfluorinated chain [chain (R f )], which comprises repeating units R o , the repeating units are independently selected from the group consisting of: (i) -CFXO-, wherein X is -F or -CF3; (ii) -CFXCFXO-, where X is the same or different at each occurrence and is -F or -CF3, provided that at least one of X is -F; (iii) -CF2CF2CF2O-; (iv) -CF2CF2CF2CF2O-; (v)-(CF2) j -CFZ-O-, wherein j is an integer from 0 to 3 and Z is a molecule having the general formula -OR (f-a) -T group, where R (f-a) is a fluoropolyoxyalkylene chain containing from 0 to 10 repeating units, the repeating units being selected from: -CFXO-, -CF2CFXO-, -CF2CF2CF2O-, -CF2CF2CF2CF2O-, wherein each X is independently -F or -CF3 and T is a C1-C3 perfluoroalkyl chain.

3. The copolymer (P) according to claim 1 or 2, wherein In block (1): - m is 0 or an integer from 1 to 2; and / or - one of R5 to R8 is a group having formula (II); and / or -R 20 is a σ bond or is selected from the group consisting of compounds having the formula (R 20 -i) to (R 20 -v) of the group: (R 20 -i) -(CF2) s1 -O-(CF2) s2 - wherein each of s1 and s2 is independently an integer from 1 to 6; (R 20 -ii) -O-(CF2) s3 - Where s3 is an integer from 1 to 6; (R 20 -iii) -O-R 400 -O-R 401 - in R 400 is a linear or branched perfluorinated alkyl chain containing from 1 to 6, preferably from 1 to 3 carbon atoms, and more preferably conforms to the formula -CF2-, -CF2CF2-, -CF2CF2CF2-, -CF2CF(CF3)-; and R401 is a linear or branched perfluorinated alkyl chain containing from 1 to 3 carbon atoms, more preferably conforming to the formula -CF2-, -CF2CF2-, -CF(CF2)-; (R 20 -iv) in R 500 is a linear perfluorinated alkyl chain containing from 1 to 6 carbon atoms and optionally interrupted by at least one oxygen atom; R 501 Is a -OR 503 The chain, where R 503 is a linear perfluorinated alkyl chain containing from 1 to 3 carbon atoms; R 502 is a linear perfluorinated alkyl chain containing from 1 to 4 carbon atoms and optionally interrupted by at least one oxygen atom; R 501 and R 502 Each of which is combined with a group X as defined in formula (II) in claim 1.

4. The copolymer (P) according to any one of claims 1 to 3, wherein In block (2) and formula (IV), R 10 Meets one of the following formulas: (R 10 -i)-(CF2) d (THE) e (CF2O) f R CF (THE) e* (CF2) d* (CF2O) f* in Each of d, d*, e, e*, f, and f* is independently zero or 1, and R CF is a perfluoroalkyl chain containing from 1 to 12 optionally interrupted by one or more oxygen atoms (R 10 -ii)-O-(C3F6O) h –(CF2) i -(C3F6O) j -THE- Where h=j and h+j is from 2 to 6, and i is from 2 to 6.

5. A method (P) comprising at least the following steps: (a) bringing into contact: - at least one perfluoropolyether polymer [PFPE peroxide] comprising at least one peroxy group; - at least one perfluorinated compound of formula (Xp): in R 21 To R 23 Each of is independently -F, or a perfluorinated linear or branched alkyl chain having from 1 to 6 carbon atoms, R 20 , X and y are as defined in claim 1 for formula (II); - at least one perfluorinated compound of formula (XX-p): in R 21 To R 23 Each of is independently -F, or a perfluorinated linear or branched alkyl chain having from 1 to 6 carbon atoms, R 31 To R 33 Each of is independently -F, or a perfluorinated alkyl group having from 1 to 6 carbon atoms, R 10 is an oxygen atom, a perfluorinated alkyl chain containing from 1 to 24 carbon atoms, optionally interrupted by at least one oxygen atom, t is zero or 1; Each of z* and z** is independently 1 or 2; and (b) reacting the PFPE peroxide, the at least one compound of formula (Xp) and the at least one compound of formula (XX-p) in the presence of UV radiation or under heating.

6. The method (P) according to claim 5, wherein: The method (P) comprises: - prior to step (a), the PFPE peroxide is subjected to a step of partial reduction of the peroxy bonds by chemical reduction or UV treatment or thermal treatment; and / or - After step (b), a step (c) of removing the solvent and / or a step (d) of fractionation.

7. The method (P) according to claim 5 or 6, wherein: The PFPE peroxide is a peroxidized perfluoropolyether polymer having two chain ends, each chain end comprising a group selected from a linear or branched perfluorinated alkyl chain containing from 1 to 6 carbon atoms or -C(=O)F, the two chain ends being bonded to a perfluoropolyether chain [chain (R f )], the perfluoropolyether chain comprises repeating units (R o ), these repeating units are independently selected from the group consisting of formula (i) to (v): (i) -CFXO-, wherein X is -F or -CF3; (ii) -CFXCFXO-, where X is the same or different at each occurrence and is -F or -CF3, provided that at least one of X is -F; (iii) -CF2CF2CF2O-; (iv) -CF2CF2CF2CF2O-; (v)-(CF2) j -CFZ-O-, wherein j is an integer from 0 to 3 and Z is a molecule having the general formula -OR (f-a) -T group, where R (f-a) is a fluoropolyoxyalkylene chain comprising from 0 to 10 repeating units, the repeating units being selected among: -CFXO-, -CF2CFXO-, -CF2CF2CF2O-, -CF2CF2CF2CF2O-, wherein each X is independently -F or -CF3 and T is a C1-C3 perfluoroalkyl chain; and having a peroxide content (PO) between 0.1 and 4, the peroxide content being defined as the grams of active oxygen in 100 g of PFPE peroxide.

8. The method (P) according to any one of claims 5 to 7, wherein: In the at least one compound having formula (Xp): -R 21 , R 22 and R 23 each of which is -F; and / or -R 20 is a sigma bond or is selected from the group consisting of 20 -i) to (R 20 -iv) of the group: (R 20 -i) -(CF2) s1 -O-(CF2) s2 - wherein each of s1 and s2 is independently an integer from 1 to 6; (R 20 -ii) -O-(CF2) s3 - Where s3 is an integer from 1 to 6; (R 20 -iii) -O-R 400 -O-R 401 - in R 400 is a linear or branched perfluorinated alkyl chain containing from 1 to 6, preferably from 1 to 3 carbon atoms, and more preferably conforms to the formula -CF2-, -CF2CF2-, -CF2CF2CF2-, -CF2CF(CF3)-; and R 401 is a linear or branched perfluorinated alkyl chain containing from 1 to 3 carbon atoms, preferably conforming to the formula -CF2-, -CF2CF2-, -CF(CF2)-; (R 20 -iv) in R 500 is a linear perfluorinated alkyl chain containing from 1 to 6 carbon atoms, optionally interrupted by at least one oxygen atom; R 501 Is a -OR 503 The chain, where R 503 is a linear perfluorinated alkyl chain containing from 1 to 3 carbon atoms; R 502 is a linear perfluorinated alkyl chain containing from 1 to 4 carbon atoms and optionally interrupted by at least one oxygen atom; R 501 and R 502 Each of which is combined with a group X as defined above in formula (II) of claim 1.

9. The method (P) according to any one of claims 5 to 8, wherein: In the compound having the formula (XX-p): - When t is 1, one, two, three or four unsaturated moieties are bonded to the 10 The residues are located on the same or different atoms of the residues, preferably on carbon atoms.

10. The method (P) according to any one of claims 5 to 9, wherein: The at least one compound having formula (XX-p) conforms to the following formula: CF2=CF(R 10 ) t CF=CF2 where t is either zero or 1, and R 10 Meets one of the following formulas: (R 10 -i)-(CF2) d (THE) e (CF2O) f R CF (THE) e* (CF2) d* (CF2O) f* in Each of d, d*, e, e*, f, and f* is independently zero or 1, and R CF is a perfluoroalkyl chain containing from 1 to 12 optionally interrupted by one or more oxygen atoms (R 10 -ii)-O-(C3F6O) h –(CF2) i -(C3F6O) j -THE- Where h=j and h+j is from 2 to 6, and i is from 2 to 6.

11. The method (P) according to any one of claims 5 to 10, wherein: - step (a) and step (b) are carried out in the presence of a fluorinated solvent; and / or - said step (b) is carried out in an inert atmosphere; - step (b) is carried out in the presence of UV radiation for a time of from 2 to 150 hours and / or at a temperature of from -60°C to +150°C; or - Step (b) is carried out under thermal treatment, preferably by heating at a temperature of from 150°C to 250°C.

12. A block copolymer [copolymer (P F )], comprising a first and a second perfluoropolyether chain [PFPE chain] each having two chain ends, wherein the first chain end of each of the first and second PFPE chains is a chain end of the copolymer (P), and each chain end comprises a group selected from: a perfluorinated linear or branched alkyl chain containing from 1 to 6 carbon atoms; -COOH and its salts with organic cations, preferably onium cations, or with inorganic cations, preferably alkali metals; -COOR, wherein R is a linear or branched alkyl chain containing from 1 to 6 carbon atoms; -COF; -CONH2; -CON(R 300 )(R 301 ), where R 300 and R 301 Each of these has the same meaning as defined for R; -(R) c OH, wherein c is 0 or 1, and R is as defined above; -C(O)-OC(O)R, wherein R is as defined above; Provided that (i) at least one of the chain ends of the first and second PFPE chains comprises a group other than a perfluorinated linear or branched alkyl chain having from 1 to 6 carbon atoms; and (ii) when one chain end comprises the group -COF, the other chain end does not comprise a perfluorinated linear or branched alkyl chain having from 1 to 6 carbon atoms or -COF; And the second chain ends of the first and second PFPE chains are bonded to each other via: - at least one first block [block (1)] conforming to formula (I): in m is 0 or an integer from 1 to 5; R5 to R8 are each independently selected from the group consisting of: -F, a perfluorinated linear or branched alkyl chain having from 1 to 6 carbon atoms, and a group having formula (II): (II)-R 20 -(X) y in R 20 is a sigma bond, or a linear or branched perfluoroalkyl chain containing from 1 to 12 carbon atoms, which preferably contains and / or is interrupted by at least one oxygen atom, X is a functional group, which is preferably selected from: -SO2F, -SO3H, -COOH, -COF, -CN, -Br and -CONH2; and y is an integer equal to 1 or 2; The prerequisite is that in formula (I), at least one, preferably one, of R5 to R8 is a group having formula (II); - at least one second block [block (2)] conforming to formula (III): (III) in n is an integer from 1 to 3; R1 to R4 are each independently selected from the group comprising: a fluorine atom, a perfluorinated linear or branched alkyl group having from 1 to 6 carbon atoms, a group having formula (IV): (IV)-(R 10 ) t [C(R 11 )(R 12 )-C(R 13 )(R 14 )(R 15 )] z in R 10 is an oxygen atom, or a divalent / trivalent / tetravalent perfluorinated alkyl chain containing from 1 to 24 carbon atoms and optionally interrupted by at least one oxygen atom, t is zero or 1, z is an integer from 1 to 3, R 11 To R 15 each independently selected from the group comprising: a fluorine atom, a perfluorinated linear or branched alkyl group having from 1 to 6 carbon atoms and a group having formula (V) as defined in claim 1; as well as - optionally, at least one third block comprising PFPE chains [block (3)]; The premise is that in the copolymer (P F )middle: - the sum of (m+f) is at least 1, preferably from 1 to 100; - the sum of (n+b) is at least 1, preferably from 1 to 15; and - the at least one block (1), the at least one block (2), and, when present, the at least one block (3) are statistically distributed.

13. A block copolymer [copolymer (P O-O )], comprising a first and a second perfluoropolyether chain [PFPE chain], wherein each of the first and the second PFPE chain is a chain (Rf) as defined in claim 2 or a chain (Rf O-O ), where (Rf O-O ) is in accordance with claim 2 for (R o ) and having a peroxide content (PO) between 0.1 and 4, the peroxide content being defined as the grams of active oxygen (Mw=16) in 100 g of PFPE peroxide, each of the first and second PFPE chains having two chain ends, wherein the first chain end of each of the first and second PFPE chains is the chain end of the copolymer (P) and each chain end 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 the first and second PFPE chains are bonded to each other via: - at least one first block [block (1)] conforming to formula (I): in m is 0 or an integer from 1 to 5; R5 to R8 are each independently selected from the group consisting of: -F, a perfluorinated linear or branched alkyl chain having from 1 to 6 carbon atoms, and a group having formula (II): (II)-R 20 -(X) y in R 20 is a sigma bond, or a linear or branched perfluoroalkyl chain containing from 1 to 12 carbon atoms, which preferably contains and / or is interrupted by at least one oxygen atom, X is a functional group, which is preferably selected from: -SO2F, -SO3H, -COOH, -COF, -CN, -Br and -CONH2; and y is an integer equal to 1 or 2; The prerequisite is that in formula (I), at least one, preferably one, of R5 to R8 is a group having formula (II); - at least one second block [block (2)] conforming to formula (III): (III) in n is an integer from 1 to 3; R1 to R4 are each independently selected from the group comprising: a fluorine atom, a perfluorinated linear or branched alkyl group having from 1 to 6 carbon atoms, a group having formula (IV): (IV)-(R 10 ) t [C(R 11 )(R 12 )-C(R 13 )(R 14 )(R 15 )] z in R 10 is an oxygen atom, or a divalent / trivalent / tetravalent perfluorinated alkyl chain containing from 1 to 24 carbon atoms and optionally interrupted by at least one oxygen atom, t is zero or 1, z is an integer from 1 to 3, R 11 To R 15 each independently selected from the group comprising: a fluorine atom, a perfluorinated linear or branched alkyl group having from 1 to 6 carbon atoms and a group having formula (V) as defined in claim 1; and / or - optionally, at least one third block comprising PFPE chains as defined in claim 2 [block (3)]; The premise is * In copolymer (P O-O )middle - the block (1), the block (2), and, when present, the block (3) are statistically distributed, – the sum of (n+b) is at least 1, preferably from 1 to 15; The sum of –(m+f) is at least 1, preferably from 1 to 100.

14. A block copolymer [copolymer (P F-O-O )], comprising a first and a second perfluoropolyether chain [PFPE chain], wherein each of the first and the second PFPE chain is a chain (Rf) as defined in claim 2 or a chain (Rf O-O ), where (Rf O-O ) is in accordance with claim 2 for (R o ) and having a peroxide content (PO) between 0.1 and 4, the peroxide content being defined as the grams of active oxygen (Mw=16) in 100 g of PFPE peroxide, each of the first and second PFPE chains having two chain ends, wherein the first chain end of each of the first and second PFPE chains is the chain end of the copolymer (P), and each chain end comprises a group selected from the group consisting of: a perfluorinated linear or branched alkyl chain containing from 1 to 6 carbon atoms; -COOH and its salts with organic cations, preferably onium cations, or with inorganic cations, preferably alkali metals; -COOR, wherein R is as defined above; -COF; -CON(R 300 )(R 301 ), where R 300 and R 301 Each of is a hydrogen atom or has the same meaning as defined for R; -(R) c OH, wherein c is 0 or 1 and R is as defined above; -C(O)-OC(O)R, wherein R is as defined above; -Br; -CN2; and the second chain ends of the first and second PFPE chains are bonded to each other via: - at least one first block [block (1)] conforming to formula (I): in m is 0 or an integer from 1 to 5; R5 to R8 are each independently selected from the group consisting of: -F, a perfluorinated linear or branched alkyl chain having from 1 to 6 carbon atoms, and a group having formula (II): (II)-R 20 -(X) y in R 20 is a sigma bond, or a linear or branched perfluoroalkyl chain containing from 1 to 12 carbon atoms, which preferably contains and / or is interrupted by at least one oxygen atom, X is a functional group, which is preferably selected from: -SO2F, -SO3H, -COOH, -COF, -CN, -Br and -CONH2; and y is an integer equal to 1 or 2; The prerequisite is that in formula (I), at least one, preferably one, of R5 to R8 is a group having formula (II); - at least one second block [block (2)] conforming to formula (III): (III) in n is an integer from 1 to 3; R1 to R4 are each independently selected from the group comprising: a fluorine atom, a perfluorinated linear or branched alkyl group having from 1 to 6 carbon atoms, a group having formula (IV): (IV)-(R 10 ) t [C(R 11 )(R 12 )-C(R 13 )(R 14 )(R 15 )] z in R 10 is an oxygen atom, or a divalent / trivalent / tetravalent perfluorinated alkyl chain containing from 1 to 24 carbon atoms and optionally interrupted by at least one oxygen atom, t is zero or 1, z is an integer from 1 to 3, R 11 To R 15 each independently selected from the group comprising: a fluorine atom, a perfluorinated linear or branched alkyl group having from 1 to 6 carbon atoms and a group having formula (V) as defined in claim 1; and / or - optionally, at least one third block comprising PFPE chains as defined in claim 2 [block (3)]; The premise is * In copolymer (P F-O-O )middle - the block (1), the block (2), and, when present, the block (3) are statistically distributed, – the sum of (n+b) is at least 1, preferably from 1 to 15; The sum of –(m+f) is at least 1, preferably from 1 to 100.

15. A mixture [mixture (M1)] comprising at least one copolymer (P) as defined in any one of claims 1 to 4 and at least one of the PFPE peroxides used as starting materials and / or a copolymer (P) as defined in claim 13 O-O ) 16. A mixture [mixture (M2)] comprising at least one copolymer as defined in claim 12 (P F ), and at least one copolymer (P) as defined in any one of claims 1 to 4, the PFPE peroxide used as starting material, the one or more copolymers (P) as defined in claim 13 O-O ) and / or said one or more copolymers as defined in claim 14 (P F-O-O ).

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