Perfluoropolyether polymers

Abstract

The present invention relates to novel copolymers comprising a (per) fluoropolyether chain and a functional group along the main chain of the copolymer as a pendant group.

Description

Cross-references to related patent applications

[0001] This patent application claims priority from application No. 22198250.7 filed in Europe on September 28, 2022, the entire contents of which are incorporated by reference into this application for all purposes. Technical Field

[0002] The present invention relates to novel copolymers comprising (per)fluoropolyether chains and functional groups as pendant groups along the copolymer backbone. Background Art

[0003] (Per)fluoropolyether polymers (hereinafter referred to as "PFPE polymers") have long been known as base oils or additives in several lubricant applications.

[0004] 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.

[0005] 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.

[0006] US 8,258,090 (in the name of Solvay Solexis SpA) discloses fluorinated lubricants having the formula: (I)TO-[AB] z -[A'-B'] z’ -AT in T and T' are C 1-3 Perfluoroalkyl or C 1-6 alkyl, A and A are perfluoropolyether chains, 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: (Ia)-[(CR1R2-CR3R4) j -(CR5R6-CR7R8) j’ ]- in j is from 1 to 5, j' is from 0 to 4 and the sum of j+j' is between 2 and 5; R1 to R8 are halogen, H, C 1-6 (Per)halogenated alkyl, C 1-6 Alkyl, C 1-6 Oxy(per)fluoroalkyl; 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; B' is (Ia), but at least one of R1 to R8 has a meaning different from that in B.

[0007] 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.

[0008] PFPE polymers containing functional groups along the backbone have been disclosed in the art and are useful as reactive intermediate compounds and additives.

[0009] 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).

[0010] 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.

[0011] Multifunctional (per)fluoropolyether polymers are further disclosed in US Pat. No. 5,719,259 (EI DuPont deNemours and Company, Feb. 17, 1998), US Pat. No. 4,853,097 (Ausimont S.rl, Aug. 1, 1989), and US Pat. No. 5,104,911 (Ausimont S.rl, Apr. 14, 1992).

[0012] 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.

[0013] 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.

[0014] 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

[0015] The problem faced by the Applicant is to provide new PFPE polymers comprising functional groups as pendant groups along the copolymer backbone. Such polymers are characterized by increased viscosity (as measured by the complex viscosity at 0.1 rad / s and 25° C.) while maintaining a low glass transition temperature (T g ) and remains liquid at room temperature.

[0016] Furthermore, the applicant has developed new PFPE copolymers containing pendant functional groups which are suitable for use as additives in different technical fields (including rust protection, wear protection) to increase the compatibility between base oils and thickeners and other ingredients dispersed in such base oils. DETAILED DESCRIPTION

[0017] For purposes of this specification and the following claims: - 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; - 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; - The term "functionality (F)" is intended to indicate the amount of functional groups in the copolymer according to the invention as measured, for example, by NMR or titration.

[0018] 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: - at least one first block [block (1)] conforming to formula (I): -[CR 100 R 101 -CR 102 R 103 ] L^ -(D) L - (I) in L^ is an integer from 1 to 250; R 100 , R 101 , R 102 and R 103 Each is independently selected from a halogen atom, more preferably a fluorine or chlorine atom; a linear or branched alkyl chain containing from 1 to 6 carbon atoms; -OR 200 , where R 200 is a straight or branched perfluorinated chain containing from 1 to 6 carbon atoms or having the formula -CF2OR 201 A group in which R 201 is a perfluorinated alkyl chain containing from 1 to 6 carbon atoms, optionally interrupted by one or more oxygen ether atoms; or R 100 and R 101 One of the 102 and R 103is a fluorine atom and R 100 and R 101 Another one in R 102 and R 103 The other of the forms together form a perhalogenated cyclic ring having from 4 to 6 members optionally containing a heteroatom such as an oxygen atom; L is 0 or an integer from 1 to 250, and D is a compound having the formula -(CR 100* R 101* -CR 102* R 103* )-, wherein R 100* , R 101* , R 102* and R 103* At least one of them is different from R 100 , R 101 , R 102 and R 103 , so that (D) is different from -[CR 100 R 101 -CR 102 R 103 ] L^ -; The premise is that when both L^ and L are not 0, the repeating units are statistically distributed; - at least one second block [block (2)] conforming to formula (II): in m is an integer from 1 to 5; 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 (III): (III)-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 (II), at least one, preferably one, of R5 to R8 is a group having formula (III); 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 (L+L^) is at least 1, preferably from 1 to 500, more preferably from 2 to 500, even more preferably from 2 to 300; - the total number of blocks (2) is from 1 to 100; 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.

[0019] Advantageously, the copolymer (P) is characterized by a complex viscosity measured at 0.1 rad / s and 25° C. that varies over a wide range, such as from 10 Pa*s to more than 2000 Pa*s. In fact, an advantage of the process for making the copolymer (P) according to the invention is that the amount of reactants providing each of the blocks (1) and (2) can be pre-adjusted and selected based on the desired properties of the final copolymer (P). This is advantageous because pre-selecting the amount of reactants allows the number of each of the blocks (1) and (2) in the copolymer (P) to be controlled and adjusted.

[0020] 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).

[0021] 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: (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.

[0022] Preferably, the chain (R f ) conforms to the following formula: (R f -I) -[(CFX 1 O) g1 (CFX 2 CFX 3 O) g2 (CF2CF2CF2O) g3 (CF2CF2CF2CF2O) g4 ]- in -X 1 independently selected from -F and -CF3, -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; - 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.

[0023] More preferably, the chain (R f ) is selected from chains having the formula: (R f -IIA)-[(CF2CF2O) a1 (CF2O) a2 ]- in: 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; (R f -IIB)-[(CF2CF2O) b1 (CF2O) b2 (CF(CF3)O) b3 (CF2CF(CF3)O) b4 ]- in: 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; (R f -IIC)-[(CF2CF2O) c1 (CF2O) c2 (CF2(CF2) cw CF2O) c3 ]- in: cw=1 or 2; 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.

[0024] Still more preferably, the chain (R f ) conforms to the following formula (R f -III): (R f -III)-[(CF2CF2O) a1 (CF2O) a2 ]- in: 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.

[0025] Preferably, in block (1), both L^ and L are not zero.

[0026] Preferably, R 100 , R 101 , R 102 and R 103 Each is independently a halogen atom such as a fluorine atom or a chlorine atom.

[0027] Preferably, in block (2), m is an integer from 1 to 2.

[0028] Preferably, in block (2), one of R5 to R8 is a group having formula (III).

[0029] Preferably, in block (2), 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, preferably from 1 to 3; (R 20 -ii) -O-(CF2) s3 - wherein s3 is an integer from 1 to 6, preferably from 1 to 5; (R 20 -iii) -OR 400 -OR 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, preferably from 1 to 3 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 above.

[0030] 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.

[0031] Advantageously, the copolymer (P) of the present invention is prepared by a process (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 above for formula (III); as well as - at least one compound selected from the group comprising, preferably consisting of: (i) perhalogenated olefins containing from 2 to 15 carbon atoms; (ii) CF2 = CFOR f , in R f is a C1-C6 (per)fluoroalkyl group, preferably -CF3, -C2F5, -C3F7; a group containing a chain oxygen atom C1-C 12 [(per)fluoro]-oxyalkyl, preferably perfluoro-2-propoxypropyl; (iii) CF2 = CFOCF2OR f2 in R f2 is selected from the group consisting of: C1-C6 perfluoroalkyl; C5-C6 cyclic perfluoroalkyl, and C2-C6 perfluorooxyalkyl containing at least one chain oxygen atom, preferably R f2 is -CF2CF3, -CF2CF2OCF3, or -CF3; (iv)CF2=CFCF2OR f7 in R f7 Selected from the group consisting of: C1-C6 perfluoroalkyl, C5-C6 cyclic perfluoroalkyl and C2-C6 perfluorooxyalkyl containing at least one chain oxygen atom; (v) Perfluorodioxole having the formula: Where Rf3 , R f4 , R f5 , R f6 Each of which is the same as or different from each other and is independently selected from the group consisting of: a fluorine atom and a C1-C6 perfluoroalkyl group optionally containing one or more than one oxygen atom, such as especially -CF3, -C2F5, -C3F7, -OCF3, -OCF2CF2OCF3; (b) reacting the PFPE peroxide, the at least one compound of formula (Xp) and the at least one compound (O) in the presence of UV radiation or under heating.

[0032] In step (a), the order of addition of the reactants is not limited. Thus, PFPE peroxide, compound having formula (Xp) and compound (O) can be fed into the reaction environment in any order.

[0033] 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.

[0034] 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.

[0035] 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.

[0036] According to a preferred embodiment, step (a) of the process of the invention is carried out with at least one compound (O).

[0037] Preferably, the at least one compound (O) is selected from the group comprising, preferably consisting of: (i) Perhalogenated olefins containing 2 to 10 carbon atoms, preferably from 2 to 8 carbon atoms. More preferably, they are selected from the group consisting of tetrafluoroethylene (TFE), hexafluoropropylene (HFP), chlorotrifluoroethylene (CTFE). TFE and HFP are particularly preferred.

[0038] When two or more compounds (O) are used, preferably, the first compound (O) is selected from those defined in (i) above, and the second compound (O) is selected in the group comprising, more preferably consisting of: (ii) CF2 = CFOR f , in R f is a C1-C6 (per)fluoroalkyl group, preferably -CF3, -C2F5, -C3F7; a group containing a chain oxygen atom C1-C 12 [(per)fluoro]-oxyalkyl, preferably perfluoro-2-propoxypropyl; (iii) CF2 = CFOCF2OR f2 in R f2 is selected from the group consisting of: C1-C6 perfluoroalkyl; C5-C6 cyclic perfluoroalkyl, and C2-C6 perfluorooxyalkyl containing at least one chain oxygen atom, preferably R f2 is -CF2CF3, -CF2CF2OCF3, or -CF3; (iv)CF2=CFCF2OR f7 in R f7 Selected from the group consisting of: C1-C6 perfluoroalkyl, C5-C6 cyclic perfluoroalkyl and C2-C6 perfluorooxyalkyl containing at least one chain oxygen atom; (v) Perfluorodioxole having the formula: Where R f3 , R f4 , R f5 , R f6 Each of which is the same as or different from each other and is independently selected from the group consisting of a fluorine atom and a C1-C6 perfluoroalkyl group optionally containing one or more than one oxygen atom, such as especially -CF3, -C2F5, -C3F7, -OCF3, -OCF2CF2OCF3.

[0039] Preferably, in the at least one compound having formula (Xp), R 21 , R 22 and R23 Each of them is -F.

[0040] Preferably, in the compound (Xp), R 20 is a sigma bond or a group having the formula: (R 20 -i)-(CF2) s1 -O-(CF2) s2 - wherein each of s1 and s2 is independently an integer from 1 to 6, preferably from 1 to 3; (R 20 -ii)-O-(CF2) s3 - wherein s3 is an integer from 1 to 6, preferably from 1 to 5; (R 20 -iii)-OR 400 -OR 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, preferably from 1 to 3 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 above.

[0041] According to a particularly preferred embodiment, the at least one compound having formula (Xp) is selected from: CF2=CFCF2OCF2CF2COOH CF2=CFOCF2COOH CF2=CFO(CF2)5COOH CF2=CFOCF2CF2OCF2COOH CF2=CFOCF2CF2COOH CF2=CFCF2OCF2CF2COF CF2=CFOCF2COF CF2=CFO(CF2)3OCF(CF3)COF CF2=CFO(CF2)5COF CF2=CFOCF2CF(CF3)OCF2CF2CN CF2=CFOCF2CN CF2=CFO(CF2)5CN CF2=CFO(CF2)3OCF(CF3)CN CF2=CFCF2OCF2CF2CN CF2=CFOCF2CF2Br CF2=CFCF2OCF2CF2Br CF2=CFOCF2CF(CF3)OCF2CF2Br CF2=CFCF2OCF2CF2CONH2 CF2=CFOCF2CONH2 CF2=CFOCF2CF2CONH2 CF2=CFOCF2CF2SO2F CF2=CFSO2F CF2=CFOCF2CF(SO2F)2 CF2=CFOCF2CF(CF2OCF2CF2SO2F)(OCF2CF2SO2F) CF2=CFOCF2CF(CF2CF2SO2F)(OCF2CF2SO2F) CF2=CFOCF2OCF2CF(CF2OCF2CF2SO2F)(SO2F)

[0042] 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.).

[0043] The amount of each of the at least one compound (Xp) and compound (O) is not limited.

[0044] For example, the equivalents of double bonds of the compound (Xp) to the equivalents of peroxy groups may range from 1:100 to 5000:100.

[0045] Step (a) of process (P) can advantageously be carried out by contacting the PFPE peroxide with a compound of formula (Xp).

[0046] Alternatively, the step (a) may be performed by contacting the PFPE peroxide with two or more compounds of formula (Xp).

[0047] Step (a) and step (b) may be carried out in the presence of a fluorinated solvent. Preferably, the fluorinated solvent is selected from the group consisting of perfluorocarbons, hydrofluorocarbons, perfluoropolyethers, hydrofluoropolyethers.

[0048] 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.

[0049] 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.

[0050] 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.

[0051] Preferably, the step (b) is carried out in an inert atmosphere.

[0052] In a third aspect, the present invention relates to a copolymer (P) obtained by process (P) as described above.

[0053] Advantageously, the functional groups introduced as side groups in block (2) 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.

[0054] 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).

[0055] Advantageously, the functionalized copolymers according to the invention [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.

[0056] The present invention further encompasses the copolymer (P) obtained at the end of step (c) of process (P) F ).

[0057] 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; 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): -[CR 100 R 101 -CR 102 R 103 ] L^ -(D) L - (I) in L^, L, D, R 100 , R 101 , R 102 and R 103 has the meaning defined above; - at least one second block [block (2)] conforming to formula (II): in m, R5 to R8 have the meanings defined above; 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 (L+L^) is from 1 to 500, more preferably from 2 to 500, more preferably from 2 to 300; - the total number of blocks (2) is from 1 to 100; 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.

[0058] In another aspect, the present invention relates to a mixture [mixture (P F )], which comprises two or more copolymers as defined above (P F ).

[0059] Although a purification step may be performed after any of step (b), step (c) and / or step (d) of the process (P), typically the copolymer (P) or copolymer (P) according to the present invention is obtained. F ).

[0060] Therefore, in a further aspect, the present invention relates to a mixture [mixture (P)] comprising two or more copolymers (P) as defined above.

[0061] It will be clear to the skilled person that mixture (P) is obtained by process (P) as described above.

[0062] Advantageously, the mixture (P) may be subjected to one or more purification steps (also called "fractionation" steps) so as to obtain individual copolymers (P) characterized by different viscosities and / or 19 The number average molecular weight and / or functionality (F) measured by F-NMR is preferably from 3 to 102.

[0063] 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 )].

[0064] Advantageously, the copolymer (P O-O ) and / or copolymer (P F-O-O ) can be isolated and used as intermediates in other processes.

[0065] 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%.

[0066] More preferably, the amount of peroxy groups is up to 1.0%, even more preferably up to 0.5%, and still more preferably up to 0.1%.

[0067] 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: - at least one first block according to formula (I) as defined above [block (1)]; - at least one second block conforming to formula (II) as defined above [block (2)]; as well as - optionally, at least one third block comprising PFPE chains as defined above [block (3)]; The premise is * In copolymer (P O-O )middle - the block (1), the block (2), and, when present, the at least one block (3) are statistically distributed, – the sum of (L+L^) is at least 1, preferably from 1 to 500, more preferably from 2 to 500, more preferably from 2 to 300; - The total number of blocks (2) is from 1 to 100.

[0068] 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: - at least one first block according to formula (I) as defined above [block (1)]; - at least one second block conforming to formula (II) as defined above [block (2)]; as well as - optionally, at least one third block comprising PFPE chains as defined above [block (3)]; The premise is * In copolymer (P F-O-O )middle - the block (1), the block (2), and, when present, the at least one block (3) are statistically distributed, – the sum of (L+L^) is at least 1, preferably from 1 to 500, more preferably from 2 to 500, more preferably from 2 to 300; - The total number of blocks (2) is from 1 to 100.

[0069] 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 the copolymer (P) as defined above used as starting materials. O-O )

[0070] In 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 as defined above (P F-O-O ).

[0071] 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.

[0072] 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.

[0073] Advantageously, therefore, the copolymer (P) is in the liquid state at room temperature.

[0074] Furthermore, advantageously, the copolymer (P F ) is in liquid state at room temperature.

[0075] 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.

[0076] The copolymer (P) and / or copolymer (P F ) is suitable for use as an additive in different technical fields (including rust prevention and wear resistance) to increase the compatibility between base oil and thickener and other ingredients dispersed in such base oil.

[0077] 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.

[0078] 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. Experimental Section

[0079] Material

[0080] Perfluoropolyether peroxide oil was obtained from Solvay Specialty Polymers Italy and conforms to the following formula XO-(CF2CF2O) a1 (CF2O) a2 (O) h -X' in X and X' are -CF3, -CF2COF, -COF, and have the following properties: Mn=31 990g / mol; PO=1.61%; m / n=1.0

[0081] The following were purchased from Anles and are used as is: Perfluorovinyl cyanide (8CNVE) CF2 = CFOCF2CF (CF3) OCF2CF2CN

[0082] 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.

[0083] method:

[0084] 19 F-NMR-Using 19 The structure, molecular weight, chain end composition and functionality of the perfluoropolyether oil were obtained using a Varian Mercury 300 MHz spectrometer operating on a F core. CFCl3 was used as an internal standard to obtain the 19 F-NMR spectrum.

[0085] 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%.

[0086] FT-IR spectra were obtained on liquid samples (as thin films on KBr) using a Thermo Fisher IS10 spectrometer.

[0087] Complex viscosity was measured by frequency sweep test 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.

[0088] Example 1a - Preparation of PFPE Copolymers Containing TFE, MVE and VEFS

[0089] 251g of the above-mentioned peroxidized perfluoropolyether oil is loaded into a 1500mL stirred cylindrical photochemical reactor equipped with a high pressure mercury lamp model HANAU TQ150, a thermocouple, a condenser and a mechanical stirrer. The oil is diluted with 1876g of a perfluorinated solvent Galden HT200, and 14.0g of VEFS is added to the reactor. Then, under stirring, the mixture is purged with nitrogen, and thereafter, two fluorinated olefins PMVE and TFE are introduced into the reactor at a rate of 14.6 and 8.0g / h, respectively. After the flow begins, the UV lamp is turned on, and the reaction is carried out for 7h at 20°C. After this period of time, the olefin stream is interrupted and the UV lamp is turned off.

[0090] 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.

[0091] 275.1 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.

[0092] Product 19 F-NMR analysis confirmed the absence of residual peroxide.

[0093] The incorporation concentrations of VEFS, TFE and PMVE in the copolymer are 3.8, 13.4 and 9.6 wt %, respectively.

[0094] 19 F-NMR analysis confirmed the following structure: XO-(CF2CF2O) a1 (CF2O) a2 [CF2CFO(CF2CF2SO2F)] m (CF2CF2) L^ -[CF2CF(OCF3)] L -X' in a1 / a2=0.9, m = 3.8, L^ = 47.8, L = 20.6 (all values ​​are averages and are statistically distributed) X and X' = -CF3, -CF2COF and -OCOF, and Number average molecular weight (M n )=35600g / mol.

[0095] Example 1b - Preparation of PFPE Copolymers Containing TFE, MVE and VEFS

[0096] The polymer was prepared following the same procedure disclosed in Example 1 above, except that 23.3 g of VEFS was provided.

[0097] 279.9 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.

[0098] Product 19 F-NMR analysis confirmed the absence of residual peroxide.

[0099] The incorporation concentrations of VEFS, TFE and PMVE in the copolymer were 5.0, 12.7 and 11.4 wt %, respectively.

[0100] 19 F-NMR analysis confirmed the following structure: XO-(CF2CF2O) a1 (CF2O) a2 [CF2CFO(CF2CF2SO2F)] m (CF2CF2) L^ -[CF2CF(OCF3)] L -X' in a1 / a2=1.0, m = 6.8, L^ = 48.9, L = 26.5 (all values ​​are average values, and the blocks are statistically distributed) X and X' = -CF3, -CF2COF and -OCOF; Number average molecular weight (M n )=38500g / mol.

[0101] Comparative Example 1 - Preparation of PFPE Copolymers Containing VEFS

[0102] 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 1875 g of the perfluorinated solvent Galden 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.

[0103] 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.

[0104] 215.9 g of copolymer are obtained as residue in the form of a clear oil, which is analyzed by iodine titration to confirm complete removal of the peroxide units.

[0105] The VEFS concentration in the copolymer was 6.0 wt%.

[0106] Product 19 F-NMR analysis confirmed the absence of residual peroxide and the following structure: XO-(CF2CF2O) a1 (CF2O) a2 (CF2CFO(CF2CF2SO2F)) m -X' Where a1 / a2=1.0, Average m = 5.6 X and X'=-CF3, -CF2COF and -OCOF Number average molecular weight (Mn) = 30400 g / mol.

[0107] Example 2 - Preparation of PFPE Copolymers Containing TFE, MVE and 8CNVE

[0108] 250 g of the peroxidized perfluoropolyether oil described above was charged to the same reactor as in Example 1. The oil was diluted with 1875 g of the perfluorinated solvent Galden D100 and 29.2 g of 8CNVE was added to the reactor.

[0109] The mixture was then purged with nitrogen under stirring, after which two fluorinated olefins PMVE and TFE were introduced into the reactor at rates of 17.1 and 9.3 g / h, respectively. After the flow began, the UV lamp was turned on and the reaction was carried out at 20° C. for 6 h. After this period of time, the olefin flow was interrupted and the UV lamp was kept at 20° C. for another 35 hours.

[0110] After a total of 35 hours of UV irradiation, the lamp 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 until the solvent and unreacted traces of monomers were completely removed.

[0111] 265 g of a copolymer were obtained as a residue in the form of a transparent viscous oil.

[0112] The incorporation concentrations of 8CNVE, TFE, and PMVE in the copolymers were 7.3, 12.0, and 11.4 wt%, respectively. The introduction of -CN functional groups was also confirmed by FT-IR spectroscopy, confirming the presence of 2269 cm -1 The existence of the peak at.

[0113] Product 19 F-NMR analysis confirmed the copolymer structure: XO-(CF2CF2O) a1 (CF2O) a2 -(CF2CFO(CF2CF(CF3)OCF2CF2CN)) m (CF2CF2) L^ -(CF2CF(OCF3)) L -X' in a1 / a2=0.9, m=6.6、L^=42.0、L=24.0 (all values ​​are average values, and the repeating units are statistically distributed) X and X' = -CF3, -CF2COF and -OCOF; and Number average molecular weight (M n )=35000g / mol.

[0114] Comparative Example 2 - Preparation of PFPE Copolymers Containing 8CNVE

[0115] 252.1 g of the peroxidized perfluoropolyether oil described above was charged to the same reactor as in Example 1. The oil was diluted with 1873 g of the perfluorinated solvent Galden 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.

[0116] 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.

[0117] 224.5 g of a copolymer were obtained as a residue in the form of a transparent viscous oil.

[0118] 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.

[0119] The incorporation concentration of 8CNVE in the copolymer is 8.0%.

[0120] Product 19 F-NMR analysis confirmed the copolymer structure: XO-(CF2CF2O) a1 (CF2O) a2 -(CF2CFO(CF2CF(CF3)OCF2CF2CN)) m -X' in a1 / a2=0.9, m=6.4 X and X' = -CF3, -CF2COF and -OCOF; and Number average molecular weight (M n )=31 100g / mol.

[0121] The properties of the copolymers according to the invention and comparative copolymers are summarized in Table 1 below. Table 1 (*)contrast

[0122] The above data show that in the copolymers according to the invention, the complex viscosity increases by an order of magnitude, while the molecular weight remains comparable.

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): -[CR 100 R 101 -CR 102 R 103 ] L^ -(D) L - (I) in L^ is an integer from 1 to 250; R 100 , R 101 , R 102 and R 103 Each is independently selected from a halogen atom, more preferably a fluorine or chlorine atom; a linear or branched alkyl chain containing from 1 to 6 carbon atoms; -OR 200 , where R 200 is a straight or branched perfluorinated chain containing from 1 to 6 carbon atoms or having the formula -CF2OR 201 A group in which R 201 is a perfluorinated alkyl chain containing from 1 to 6 carbon atoms, optionally interrupted by one or more oxygen ether atoms; or R 100 and R 101 One of the 102 and R 103 is a fluorine atom and R 100 and R 101 Another one in R 102 and R 103 The other of the forms together form a perhalogenated cyclic ring having from 4 to 6 members optionally containing a heteroatom such as an oxygen atom; L is 0 or an integer from 1 to 250, and D is a compound having the formula -(CR 100* R 101* -CR 102* R 103* )-, wherein R 100* , R 101* , R 102* and R 103* At least one of them is different from R 100 , R 101 , R 102 and R 103 , so that (D) is different from -[CR 100 R 101 -CR 102 R 103 ] L^ -; The premise is that when both L^ and L are not 0, the repeating units are statistically distributed; - at least one second block [block (2)] conforming to formula (II): in m is an integer from 1 to 5; 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 (III): (III)-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 (II), at least one, preferably one, of R5 to R8 is a group having formula (III); 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 (L+L^) is at least 1, preferably from 1 to 500, more preferably from 2 to 500, more preferably from 2 to 300; - the total number of blocks (2) is from 1 to 100; 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 fully fluorinated chain comprising, preferably consisting of, repeating units R° [chain (R f )], 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 the block (1): - Both L^ and L are not 0; and / or -R 100 , R 101 , R 102 and R 103 Each is independently a halogen atom, preferably selected from a fluorine atom or a chlorine atom.

4. The copolymer (P) according to any one of claims 1 to 3, wherein In the block (2): - m is an integer from 1 to 2; and / or - one of R5 to R8 is a group of formula (III); 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, preferably from 1 to 3; (R 20 -ii) -O-(CF2) s3 - wherein s3 is an integer from 1 to 6, preferably from 1 to 5; (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, preferably from 1 to 3 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 as defined in claim 1 -(X) y .

5. A method for producing a copolymer (P) according to any one of claims 1 to 4 [method (P)], the method (P) comprising 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 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 (II), at least one, preferably one, of R5 to R8 is a group having formula (III); as well as - at least one compound selected from the group comprising, preferably consisting of: (i) perhalogenated olefins containing from 2 to 15 carbon atoms; (ii)CF2=CFOR f , in R f is a C1-C6 (per)fluoroalkyl group, preferably -CF3, -C2F5, -C3F7; a group containing chain oxygen atoms C1-C 12 [(per)fluoro]-oxyalkyl, preferably perfluoro-2-propoxypropyl; (iii)CF2=CFOCF2OR f2 in R f2 is selected from the group consisting of: C1-C6 perfluoroalkyl; C5-C6 cyclic perfluoroalkyl, and C2-C6 perfluorooxyalkyl containing at least one chain oxygen atom, preferably R f2 is -CF2CF3, -CF2CF2OCF3, or -CF3; (iv)CF2=CFCF2OR f7 in R f7 Selected from the group consisting of: C1-C6 perfluoroalkyl, C5-C6 cyclic perfluoroalkyl and C2-C6 perfluorooxyalkyl containing at least one chain oxygen atom; (v) Perfluorodioxole having the formula: Where R f3 , R f4 , R f5 , R f6 Each of which is the same as or different from each other and is independently selected from the group consisting of: a fluorine atom and a C1-C6 perfluoroalkyl group optionally containing one or more than one oxygen atom, such as especially -CF3, -C2F5, -C3F7, -OCF3, -OCF2CF2OCF3; (b) reacting the PFPE peroxide, the at least one compound of formula (Xp) and the at least one compound (O) in the presence of UV radiation or under heating.

6. The method (P) according to claim 5, wherein: Prior to step (a), the PFPE peroxide is subjected to partial reduction of the peroxy bonds by chemical reduction or UV treatment or thermal treatment.

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, preferably consists of, repeating units (R°), these The repeating units are independently selected from the group consisting of formulae (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 method (P) one compound (O) is used, and said one compound (O) is selected from the group consisting of: (i) Perhalogenated olefins containing from 2 to 10 carbon atoms, preferably from 2 to 8 carbon atoms.

9. The method (P) according to any one of claims 5 to 7, wherein: In process (P) at least two compounds (O) are used, and The first compound (O) is selected from the group consisting of: (i) a perhalogenated olefin containing from 2 to 10 carbon atoms, preferably from 2 to 8 carbon atoms; and The second compound (O) is selected from the group comprising, more preferably consisting of: (ii)CF2=CFOR f , in R f is a C1-C6 (per)fluoroalkyl group, preferably -CF3, -C2F5, -C3F7; a group containing a chain oxygen atom C1-C 12 [(per)fluoro]-oxyalkyl, preferably perfluoro-2-propoxypropyl; (iii)CF2=CFOCF2OR f2 in R f2 is selected from the group consisting of: C1-C6 perfluoroalkyl; C5-C6 cyclic perfluoroalkyl, and C2-C6 perfluorooxyalkyl containing at least one chain oxygen atom, preferably R f2 is -CF2CF3, -CF2CF2OCF3, or -CF3; (iv)CF2=CFCF2OR f7 in R f7 Selected from the group consisting of: C1-C6 perfluoroalkyl, C5-C6 cyclic perfluoroalkyl and C2-C6 perfluorooxyalkyl containing at least one chain oxygen atom; (v) Perfluorodioxole having the formula: Where R f3 , R f4 , R f5 , R f6 Each of which is the same as or different from each other and is independently selected from the group consisting of a fluorine atom and a C1-C6 perfluoroalkyl group optionally containing one or more than one oxygen atom, such as especially -CF3, -C2F5, -C3F7, -OCF3, -OCF2CF2OCF3.

10. The method (P) according to any one of claims 5 to 9, 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, preferably from 1 to 3; (R 20 -ii) -O-(CF2) s3 - wherein s3 is an integer from 1 to 6, preferably from 1 to 5; (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, preferably from 1 to 3 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 above.

11. The method (P) according to any one of claims 5 to 10, wherein: The at least one compound having formula (Xp) is selected from the group comprising: CF2=CFCF2OCF2CF2COOH CF2=CFOCF2COOH CF2=CFO(CF2)5COOH CF2=CFOCF2CF2OCF2COOH CF2=CFOCF2CF2COOH CF2=CFCF2OCF2CF2COF CF2=CFOCF2COF CF2=CFO(CF2)3OCF(CF3)COF CF2=CFO(CF2)5COF CF2=CFOCF2CF(CF3)OCF2CF2CN CF2=CFOCF2CN CF2=CFO(CF2)5CN CF2=CFO(CF2)3OCF(CF3)CN CF2=CFCF2OCF2CF2CN CF2=CFOCF2CF2Br CF2=CFCF2OCF2CF2Br CF2=CFOCF2CF(CF3)OCF2CF2Br CF2=CFCF2OCF2CF2CONH2 CF2=CFOCF2CONH2 CF2=CFOCF2CF2CONH2 CF2=CFOCF2CF2SO2F CF2=CFSO2F CF2=CFOCF2CF(SO2F)2 CF2=CFOCF2CF(CF2OCF2CF2SO2F)(OCF2CF2SO2F) CF2=CFOCF2CF(CF2CF2SO2F)(OCF2CF2SO2F) CF2=CFOCF2OCF2CF(CF2OCF2CF2SO2F)(SO2F).

12. The method (P) according to any one of claims 5 to 11, 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.

13. 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; 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): -[CR 100 R 101 -CR 102 R 103 ] L^ -(D) L - (I) in L^, L, D, R 100 , R 101 , R 102 and R 103 has the meaning defined above; - at least one second block [block (2)] conforming to formula (II): in m, R5 to R8 have the meanings defined above; 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 (L+L^) is from 1 to 500, more preferably from 2 to 500, more preferably from 2 to 300; - the total number of blocks (2) is from 1 to 100; 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.

14. 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 as defined in claim 2 (R f ) or chain (Rf O-O ), where (Rf O-O ) is a repeating unit conforming to any one of the formulae (i) to (v) as defined for (R°) in claim 2 and having a peroxide content (PO) of between 0.1 and 4, preferably between 0.1 and 3.5, 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 a 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), -[CR 100 R 101 -CR 102 R 103 ] L^ -(D) L - (I) in L^ is an integer from 1 to 250; R 100 , R 101 , R 102 and R 103 Each is independently selected from a halogen atom, more preferably a fluorine or chlorine atom; a linear or branched alkyl chain containing from 1 to 6 carbon atoms; -OR 200 , where R 200 is a straight or branched perfluorinated chain containing from 1 to 6 carbon atoms or having the formula -CF2OR 201 A group in which R 201 is a perfluorinated alkyl chain containing from 1 to 6 carbon atoms, optionally interrupted by one or more oxygen ether atoms; or R 100 and R 101 One of the 102 and R 103 is a fluorine atom and R 100 and R 101 Another one in R 102 and R 103 The other of the forms together form a perhalogenated cyclic ring having from 4 to 6 members optionally containing a heteroatom such as an oxygen atom; L is 0 or an integer from 1 to 250, and D is a compound having the formula -(CR 100* R 101* -CR 102* R 103* )-, wherein R 100* , R 101* , R 102* and R 103* At least one of them is different from R 100 , R 101 , R 102 and R 103 , so that (D) is different from -[CR 100 R 101 -CR 102 R 103 ] L^ -; The premise is that when both L^ and L are not 0, the repeating units are statistically distributed; - at least one second block conforming to formula (II) [block (2)] in m is an integer from 1 to 5; 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 (III): (III)-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 (II), at least one, preferably one, of R5 to R8 is a group having formula (III); as well as - optionally, at least one third block comprising PFPE chains [block (3)]; The premise is * In copolymer (P O-O )middle - the block (1), the block (2), and, when present, the at least one block (3) are statistically distributed, – the sum of (L+L^) is at least 1, preferably from 1 to 500, more preferably from 2 to 500, more preferably from 2 to 300; - The total number of blocks (2) is from 1 to 100.

15. A mixture [mixture (M1)] comprising at least one copolymer (P) according to any one of claims 1 to 4 and at least one PFPE peroxide according to any one of claims 5 and 7 and / or a copolymer (P) according to claim 14 O-O ) 16. 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 as defined in claim 2 (R f ) or chain (Rf O-O ), where (Rf O-O ) is a repeating unit conforming to any one of the formulae (i) to (v) as defined for (R°) in claim 2 and having a peroxide content (PO) between 0.1 and 4, preferably between 0.1 and 3.5, 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 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 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; -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) -[CR 100 R 101 -CR 102 R 103 ] L^ -(D) L - (I) in L^ is an integer from 1 to 250; R 100 , R 101 , R 102 and R 103 Each is independently selected from a halogen atom, more preferably a fluorine or chlorine atom; a linear or branched alkyl chain containing from 1 to 6 carbon atoms; -OR 200 , where R 200 is a straight or branched perfluorinated chain containing from 1 to 6 carbon atoms or having the formula -CF2OR 201 A group in which R 201 is a perfluorinated alkyl chain containing from 1 to 6 carbon atoms, optionally interrupted by one or more oxygen ether atoms; or R 100 and R 101 One of the 102 and R 103 is a fluorine atom and R 100 and R 101 Another one in R 102 and R 103 The other of the forms together form a perhalogenated cyclic ring having from 4 to 6 members optionally containing a heteroatom such as an oxygen atom; L is 0 or an integer from 1 to 250, and D is a compound having the formula -(CR 100* R 101* -CR 102* R 103* )-, wherein R 100* , R 101* , R 102* and R 103* At least one of them is different from R 100 , R 101 , R 102 and R 103 , so that (D) is different from -[CR 100 R 101 -CR 102 R 103 ] L^ -; The premise is that when both L^ and L are not 0, the repeating units are statistically distributed; - at least one second block conforming to formula (II) [block (2)] in m is an integer from 1 to 5; 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 (III): (III)-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 (II), at least one, preferably one, of R5 to R8 is a group having formula (III); as well as - optionally, at least one third block comprising PFPE chains [block (3)]; The premise is * In copolymer (P F-O-O )middle - the block (1), the block (2), and, when present, the at least one block (3) are statistically distributed, – the sum of (L+L^) is at least 1, preferably from 1 to 500, more preferably from 2 to 500, more preferably from 2 to 300; - The total number of blocks (2) is from 1 to 100.

17. A mixture [mixture (M2)] comprising at least one copolymer according to claim 13 (P F ), and at least one copolymer (P) according to any one of claims 1 to 4, at least one PFPE peroxide according to any one of claims 5 and 7, at least one copolymer (P O-O ), and / or at least one copolymer according to claim 16 (P F-O-O ).

Images