Perfluoropolyether polymers

Abstract

This patent application relates to a novel perfluoropolyether polymer comprising functionalized side groups along the main chain of a perfluoropolyether.

Description

Technical Field

[0001] This patent application relates to a novel perfluoropolyether polymer comprising functionalized side groups along the main chain of a perfluoropolyether. [] [Cross-reference to related patent applications] [] []

[0002] This application claims priority to Nr 21216316.6 filed in Europe on 21 December 2021, the entire contents of which are incorporated herein by reference for all purposes. Prior Technology

[0003] Among fluorinated polymers, perfluoropolyether polymers (PFPEs) are well-known and have attracted much attention due to their chemical and physical properties.

[0004] PFPE polymers containing functional groups along the main chain have been disclosed in the art and can be used as reactive intermediate compounds.

[0005] Perfluoropolyether polymers obtained by reacting polyperoxyfluoropolyether and fluorinated olefins in the presence of UV radiation have been disclosed. [US 4,500,739] (Montedison SpA, February 19, 1985).

[0006] [US 6,403,539] (Ausimont SpA, June 11, 2002) disclosed a perfluoropolyether polymer containing sulfonyl fluoride groups as side groups along the main chain. However, for safety reasons, the presence of peroxy groups is undesirable.

[0007] Multifunctional (all)fluoropolyether polymers are further revealed in [US 5,719,259] (DuPont, Inc., February 17, 1998) [US 4,853,097] (Ausimont Srl, August 1, 1989) [US 5,104,911] (Osemont Corporation, April 14, 1992).

[0008] [US 2011 / 0230631] (Solvay Solexis SpA, September 22, 2011) discloses a (per)fluoropolyether comprising at least one (per)fluoropolyoxyalkylene chain containing at least one repeating unit having the formula -CF 2-CF(CF 2O-SO 2F)-O-, wherein the fluorosulfate group enclosed in parentheses is a side group, which subsequently reacts with a nucleophile to provide a functional group, such notably a carboxylic acid, fluoropolymer, fluoroamine, or ester.

[0009] [CN 103724559] (ZHONGHAO CHENGUANG RES INST CHEMICAL IND, April 16, 2014) discloses a method comprising placing a perfluoropolyether peroxide prepared by photo-oxidation in an inert fluorine-containing solvent, introducing a perfluoroolefin under ultraviolet irradiation, and reacting the perfluoroolefin with the peroxide to form a stable perfluoropolyether compound.

[0010] [WO 2019 / 048394] (Solvay Specialty Polymers Italy SpA, March 14, 2019) disclosed a multifunctional perfluoropolyether derivative comprising multiple ionizable groups selected from the group consisting of -SO3Xa, -PO3Xa and -COOXa, wherein Xa is H, ammonium or monovalent metal. Summary of the Invention

[0011] The applicant has developed a new perfluoropolyether polymer that can be obtained by inserting at least one asymmetric olefin along the perfluoropolyether backbone.

[0012] Therefore, in a first aspect, the present invention relates to a block copolymer [copolymer (P)] comprising first and second perfluoropolyether chains [PFPE chains] each having two chain ends, wherein the first chain end of each of the first and second PFPE chains is a chain end of copolymer (P), and each chain end comprises a group selected from perfluorinated linear or branched alkyl chains comprising 1 to 6 carbon atoms and -C(=O)F, and the second chain ends of the first and second PFPE chains are bonded to each other by blocks having formula (I): in The z-family consists of integers from 1 to 100. (A) is a PFPE chain, and (B) is a group having at least one of the following formula (II): in n is an integer from 1 to 5, preferably from 1 to 2; R1 to R4 are each independently selected from the group consisting of, preferably, the following: -F, perfluorinated straight-chain or branched alkyl chains having 1 to 6 carbon atoms, and groups having formula (III): in The R 10 series comprises straight-chain or branched perfluoroalkyl chains with 1 to 12 carbon atoms, preferably containing at least one oxygen atom. The X-series functional groups are preferably selected from: -COOH, -COF, -CN, -Br, and -CONH2; and b is an integer equal to 1 or 2; in * In equation (I), systems (A) and (B) are arranged in a random (irregular) manner; * In formula (II), at least one of R1 to R4, preferably a group having a group of formula (III); and * The total number of groups B in the copolymer (P) ranges from 1 to 100.

[0013] In a second aspect, the present invention relates to a method [method (P)] for manufacturing a copolymer (P) as defined above.

[0014] Advantageously, the copolymer (P) of the present invention is prepared by method (P), which includes: (a) Contact the following items: - At least one perfluoropolyether polymer containing a peroxy group [PFPE peroxide]; - At least one perfluorinated compound having the formula (Xp): in Each of R 21 to R 23 is independently -F, or a perfluorinated straight-chain or branched alkyl chain having 1 to 6 carbon atoms. R 10, X, and b are as defined above for equation (III); (b) React the PFPE peroxide and the compound having the formula (Xp) in the presence of UV radiation or under heating.

[0015] In the method (P) according to the invention, the amount of at least one perfluorinated compound having the formula (Xp) may be suitably selected to provide a copolymer (P), characterized by low or high content of side functional groups along the main chain of the copolymer (P).

[0016] In another aspect, the present invention relates to copolymers (P) obtained by the method (P) described above.

[0017] Although the purification step can be performed at the end of the method (P), those skilled in the art will understand that the copolymer (P) according to the invention is obtained as a mixture at the end of the method (P).

[0018] Therefore, in another aspect, the present invention relates to a mixture [mixture (P)] comprising two or more copolymers (P) as defined above.

[0019] Those familiar with this technique will know that the mixture (P) is obtained by the method (P) described above.

[0020] Advantageously, the mixture (P) can undergo one or more purification steps (also known as "fractionation") to obtain individual copolymers (P), characterized by different number average molecular weights and / or functionalities (F) as measured by 19F-NMR, preferably from 3 to 102. Implementation

[0021] For the purposes of this specification and the following claims: - The use of parentheses around identifying symbols or numbers, such as in expressions like "polymer (P)," serves only to better distinguish the symbol or number from the rest of the text, and therefore the parentheses can be omitted; - The acronym "PFPE" stands for "perfluoropolyether" and when used as a noun, it refers to either the singular or plural form depending on the context; - The term "functionality (F)" is intended to indicate the number of functional groups in the copolymer according to the invention, which includes both functional groups derived from groups (X) represented by formulas (II) and (Xp) and functional groups at each end of the copolymer (P).

[0022] In the copolymer (P), the first chain ends of each of the first and second PFPE chains may be the same or different from each other, and are selected from perfluorinated alkyl chains containing 1 to 3 carbon atoms and -C(=O)F.

[0023] According to a preferred embodiment, one of the first chain ends of each of the first and second PFPE chains contains a group -C(=O)F, and the other chain end contains a perfluorinated alkyl chain containing 1 to 3 carbon atoms.

[0024] Preferably, in the copolymer (P), the at least one PFPE chain (A) is bonded to a chain end and / or the at least one group (B) by a σ bond or a group selected from -CF 2-, -CF 2CF 2- or -O-.

[0025] Preferably, in the copolymer (P), the at least one group (B) is bonded to a chain end and / or the at least one PFPE chain (A) by a σ bond or a group-(C)- as defined above.

[0026] Preferably, in the copolymer (P), each system of the PFPE chain comprises a repeating unit R°, preferably a fully fluorinated chain [chain (Rf)] composed thereof, the repeating unit being independently selected from the group consisting of: (i)-CFXO-, where X is -F or -CF 3; (ii) -CFXCFXO-, where X is the same or different each time it appears, and is a series of -F or -CF 3, provided that at least one of X is a series of -F; (iii) ; (iv) ; (v)-(CF 2) j-CFZ-O-, wherein j is an integer from 0 to 3 and Z is a group having the general formula -OR (fa)-T, wherein R (fa) is a fluoropolyoxyalkyl chain containing 0 to 10 repeating units, the repeating units being selected from among: -CFXO-, -CF 2CFXO-, -CF 2CF 2CF 2O-, -CF 2CF 2CF 2CF 2O-, wherein each X is independently -F or -CF 3 and T is a C 1-C 3 perfluoroalkyl chain.

[0027] Preferably, the chain (Rf) conforms to the following formula: in - X 1 is selected independently from -F and -CF 3, - X2 and X3 are either the same or different from each other and are independently -F and -CF3 each time they appear, provided that at least one of the series X is -F; - g1, g2, g3 and g4 are the same or different from each other, and are independent integers ≥ 0, such that g1 + g2 + g3 + g4 are in the range of 2 to 300, preferably from 2 to 100; if at least two of g1, g2, g3 and g4 are not zero, then the different repeating units are statistically distributed along the chain in general.

[0028] More preferably, the chain (Rf) is selected from chains having the following formula: in: - a1 and a2 are independently integers ≥ 0, such that the number average molecular weight is between 400 and 100,000, preferably between 400 and 50,000; both a1 and a2 are preferably non-zero, wherein the ratio a1 / a2 is preferably between 0.1 and 10; in: b1, b2, b3, and b4 are independently integers ≥ 0, such that the number average molecular weight is between 400 and 100,000, preferably between 400 and 50,000; more preferably, each of b1, b2, b3, and b4 is > 0. in: cw = 1 or 2; c1, c2, and c3 are independently integers ≥ 0, which are selected such that the number average molecular weight 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 typically less than 0.2.

[0029] Even better, the chain (Rf) conforms to the following equation (Rf-III): in: - a1 and a2 are integers > 0 such that the number average molecular weight is between 400 and 100,000, preferably between 400 and 50,000, wherein the ratio a1 / a2 is typically between 0.1 and 10, more preferably between 0.2 and 5.

[0030] Preferably, in formula (II), at least one of the substituents R1 to R4 has a group of formula (III), and the other substituents are each independently selected from -F or a perfluorinated alkyl chain having 1 to 3 carbon atoms, more preferably -F or -CF3.

[0031] Preferably, in equation (III), b is 1.

[0032] Preferably, in formula (III), the R 10 series comprises a straight or branched perfluoroalkyl chain of 1 to 9, more preferably 1 to 6, carbon atoms and one or two oxygen atoms.

[0033] Preferably, in equation (III), R 10 conforms to the following equation: in d is zero or 1, and R CF series comprises straight-chain or branched perfluoroalkyl chains of 1 to 3 carbon atoms, or straight-chain or branched perfluoroalkyl chains of 1 to 6 carbon atoms and at least one oxygen atom.

[0034] More preferably, the R CF system comprises a straight or branched perfluoroalkyl chain of 1 to 5 carbon atoms, which may have an oxygen atom inserted as needed.

[0035] The copolymer (P) according to the invention can be advantageously prepared by the claimed method (P), which can be easily scaled up.

[0036] Prior to step (a), the PFPE peroxide may undergo partial reduction of the peroxide bonds, for example by chemical reduction or UV treatment or heat treatment.

[0037] Preferably, the PFPE peroxide is a perfluoropolyether polymer with two chain ends, each chain end comprising a group selected from a straight-chain or branched perfluoroalkyl chain or a -C(=O)F group containing 1 to 6 carbon atoms, the two chain ends being bonded to opposite sides of a perfluoropolyether chain [chain (Rf)] comprising repeating units (R°), preferably composed of such repeating units, which are independently selected from the group consisting of formulas (i) to (v) as defined above and have a peroxide content (PO) between 0.1 and 4, preferably between 0.1 and 3.5, the peroxide content being defined as the number of grams of active oxygen (Mw = 16) in 100 g of PFPE peroxide.

[0038] Preferably, in the PFPE peroxide, the chain (Rf) conforms to formula (Rf-I), or (Rf-IIA), (Rf-IIB), (Rf-IIC), or (Rf-III) as defined above.

[0039] According to a particularly preferred embodiment, the at least one compound having the formula (Xp) is selected from:

[0040] In step (a), the amount of the compound (Xp) is not limited and can be advantageously selected by those skilled in the art based on the amount and peroxide content of the PFPE peroxide and the desired final polymer. For example, the equivalent of the double bonds to the peroxy groups of the compound (Xp) can range from 1:100 to 5000:100. As will be understood by those skilled in the art, the compound (Xp) can be a solvent (i.e., in very excess) and separates from the copolymer (P) of the present invention at the end of the reaction, for example by distillation.

[0041] Step (a) of method (P) can advantageously be carried out by contacting the PFPE peroxide with a compound having formula (Xp). According to this embodiment, the group (B) in the copolymer (P) will be a group having formula (II) as defined above.

[0042] Alternatively, step (a) can be performed by contacting the PFPE peroxide with two or more compounds having formula (Xp). According to this embodiment, the groups (B) in the copolymer (P) will be two or more groups, each having formula (II) as defined above.

[0043] In other words, in this embodiment, the segment (I) conforms to the following formula (Ia): in Each system in z and A is as defined above. B1 is derived from the first compound (Xp), B2 is derived from the second compound (XP), and Bx is derived from the xth compound (Xp), wherein B1, B2, and Bx are randomly arranged within the block (I), and each of n1, n2, and nx is zero or an integer from 1 to 5, preferably 1 or 2, provided that at least two of n1, n2, and nx are not zero.

[0044] Steps (a) and (b) can be performed in the presence of a fluorinated solvent. Preferably, the fluorinated solvent is selected from the group consisting of: perfluorocarbons, hydrofluorocarbons, perfluoropolyethers, and hydrofluoropolyethers.

[0045] Preferably, step (b) is performed in the presence of UV radiation for a period of 2 to 150 hours, more preferably from 5 to 100 hours.

[0046] Preferably, step (b) is carried out in the presence of UV radiation at a temperature ranging from -60°C to +150°C, more preferably from -20°C to +100°C, and even more preferably from 0°C to 60°C.

[0047] As an alternative, step (b) can be performed under heat treatment, preferably by heating at a temperature from 150°C to 250°C.

[0048] Preferably, step (b) is performed in an inert atmosphere.

[0049] Advantageously, functional groups introduced as side groups along the main chain of the copolymer (P), such as -COOH, -COF, -CN, -Br and -CONH 2, and functional groups at the chain ends of the copolymer (P), such as -COF, can be appropriately reacted to obtain other different functional groups.

[0050] The phrase "reactive" is intended to indicate that, in consideration of the end use of the copolymer (P), such functional groups can be, for example, salted, hydrolyzed, or undergo various chemical reactions to provide one or more functional groups with the desired reactivity.

[0051] On another aspect, the present invention relates to a block copolymer [polymer (PF)] comprising first and second perfluoropolyether chains [PFPE chains] 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 (PF), and each chain end comprises a group selected from: a perfluorinated linear or branched alkyl chain having 1 to 6 carbon atoms; -COOH and its salts with organic cations, preferably ononium cations, more preferably ammonium or inorganic cations, preferably alkali metals, more preferably Na+, K+; -COOR, wherein R is a linear or branched alkyl chain having 1 to 6 carbon atoms, preferably 1 to 3 carbon atoms, more preferably 1 carbon atom; -COF; -CONH 2; -CON(R 100)(R 101), wherein each of R 100 and R 101 has the same meaning as defined for R; -(R) cOH, wherein c is 0 or 1, and R is as defined above; -C(O)-OC(O)R, where R is as defined above; The premise is that (i) at least one end of the first and second PFPE chains contains a group different from a perfluorinated straight-chain or branched alkyl chain having 1 to 6 carbon atoms; and (ii) when one end contains the group -COF, the other end does not contain a perfluorinated straight-chain or branched alkyl chain having 1 to 6 carbon atoms or -COF; Furthermore, the second ends of the first and second PFPE chains are bonded to each other by a segment having formula (I): in The z-family consists of integers from 1 to 100. (A) is a PFPE chain, and (B) is a group having at least one of the following formula (II): in n is an integer from 1 to 5, preferably from 1 to 2; R1 to R4 are each independently selected from the group consisting of, preferably, the following: -F, perfluorinated straight-chain or branched alkyl chains having 1 to 6 carbon atoms, and groups having formula (III): in The R 10 series comprises straight-chain or branched perfluoroalkyl chains with 1 to 12 carbon atoms, which may contain at least one or more oxygen atoms as desired. X-series functional groups, preferably selected from: -COOH and its organic cations, preferably onium cations, more preferably ammonium or inorganic cations, preferably alkali metals, more preferably salts of Na+ and K+; -COOR, wherein R is as defined above; -COF; -CON(R 100)(R 101), wherein each of the hydrogen atoms in R 100 and R 101 has the same meaning as defined for R; -(R)cOH, wherein c is 0 or 1, and R is as defined above; -C(O)-OC(O)R, wherein R is as defined above; -Br; -CN; and b is an integer equal to 1 or 2; in * In equation (I), systems (A) and (B) are arranged in a random (irregular) manner; * In formula (II), at least one of R1 to R4, preferably a group having a group of formula (III); and * The total number of groups B in the copolymer (PF) ranges from 1 to 100.

[0052] Advantageously, the copolymer (PF) according to the invention is obtained from the method (P) as described above, which further includes at least one step (c) following step (b), including salting, hydrolysis, oxidation, reduction, or another chemical reaction capable of providing one or more functional groups of interest.

[0053] The present invention further covers the copolymer (PF) obtained at the end of step (c) of method (P).

[0054] In another aspect, the present invention relates to a mixture [mixture (PF)] comprising two or more copolymers (PF) as defined above.

[0055] Although the method (P) according to the invention can be controlled, and a purification step can be performed after step (b) or step (c) of method (P), typically a mixture of one or more copolymers (P) or copolymers (PF) is obtained. The mixture may further contain PFPE peroxide as a starting material and / or a mixture of peroxy-containing copolymers (P) [polymer (POO)] and / or a mixture of peroxy-containing copolymers (PF) [polymer (PFOO)].

[0056] In 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 used as starting materials and / or one or more of the copolymers (P OO).

[0057] In another aspect, the present invention relates to a mixture [mixture (M2)] comprising at least one copolymer (PF) as defined above, and at least one of the copolymers (P) as defined above, the PFPE peroxide, the one or more copolymers (P OO) and / or the one or more copolymers (P FOO) used as starting materials.

[0058] Advantageously, the copolymer (P OO) and / or the copolymer (P FOO) can be isolated and used as an intermediate in other methods.

[0059] Although the amount of peroxy groups present in the mixture of copolymer (P) or copolymer (PF) of the present invention can be up to 99% based on the amount of starting peroxy groups in the PFPE peroxide, the amount of peroxy groups can be appropriately adjusted to, for example, up to 95%, 90%, 85%, 80%, 75%, 70%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, 5%, depending on the end application.

[0060] More preferably, the amount of the peroxy group is up to 1%, even more preferably up to 0.5%, and even more preferably up to 0.1%.

[0061] On the other hand, the present invention relates to a block copolymer [copolymer (P OO)] comprising first and second perfluoropolyether chains [PFPE chains] conforming to formula A or (Rf OO), wherein A is as defined above, and (Rf OO) is a repeating unit conforming to any one of formulas (i) to (v) as defined above for (R°) 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 number of 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 copolymer (P), and each chain end comprises a group selected from: perfluorinated linear or branched alkyl chains having 1 to 6 carbon atoms; -COOH and organic cations, preferably ononium cations, more preferably ammonium or inorganic cations, preferably alkali metals, more preferably Na+, K+. + salts; -COOR, wherein the R series comprises a straight-chain or branched alkyl chain of 1 to 6 carbon atoms, preferably 1 to 3 carbon atoms, and more preferably 1 carbon atom; -COF; -CONH 2; -CON(R 100)(R 101), wherein each of R 100 and R 101 has the same meaning as defined for R; -(R) cOH, wherein the c series is 0 or 1, and the R series is as defined above; -C(O)-OC(O)R, wherein the R series is as defined above; Furthermore, the second ends of the first and second PFPE chains are bonded to each other by segments having formula (I OO): Where z, A, B, and (Rf OO) are as defined above, in * In equation (I OO), A, B, and (Rf OO) are arranged in a systematic (random) manner, and * The total number of groups B in the copolymer (P OO) ranges from 1 to 100.

[0062] In another embodiment, the invention relates to a block copolymer [copolymer (P FOO)] comprising first and second perfluoropolyether chains [PFPE chains] conforming to formula A or (Rf OO), wherein A is as defined above, and (Rf OO) is a repeating unit conforming to any one of formulas (i) to (v) as defined above for (R°) 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 number of 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 FOO), and each chain end comprises a group selected from: perfluorinated linear or branched alkyl chains having 1 to 6 carbon atoms; -COOH and organic cations, preferably ononium cations, more preferably ammonium or inorganic cations, preferably alkali metals, more preferably Na+, K+. + salts; -COOR, wherein the R series comprises a straight-chain or branched alkyl chain of 1 to 6 carbon atoms, preferably 1 to 3 carbon atoms, and more preferably 1 carbon atom; -COF; -CONH 2; -CON(R 100)(R 101), wherein each of R 100 and R 101 has the same meaning as defined for R; -(R) cOH, wherein the c series is 0 or 1, and the R series is as defined above; -C(O)-OC(O)R, wherein the R series is as defined above; The premise is that (i) at least one end of the first and second PFPE chains contains a group different from a perfluorinated straight-chain or branched alkyl chain having 1 to 6 carbon atoms; and (ii) when one end contains the group -COF, the other end does not contain a perfluorinated straight-chain or branched alkyl chain having 1 to 6 carbon atoms or -COF; Furthermore, the second ends of the first and second PFPE chains are bonded to each other by segments having formula (I OO): Where z, A, B, and (Rf OO) are as defined above, in * In equation (I OO), A, B, and (Rf OO) are arranged in a systematic (random) manner, and * The total number of groups B in the copolymer (P FOO) ranges from 1 to 100.

[0063] If any patent, patent application, or disclosure incorporated herein by reference conflicts with the description of this application to the extent that it may lead to ambiguity in terminology, then this description shall take precedence.

[0064] The invention will now be described with reference to the following examples, which are merely illustrative and not intended to limit the scope of the invention. [Experimental Section] [] []

[0065] [Material]

[0066] Perfluoropolyether peroxide oil was obtained from Solvay Specialty Polymers Italy and conforms to the following formula in X and X' series -CF3, -CF2COF, -COF, and have the following properties: PFPE peroxide (1) Mn=40900g / mol; PO=1.45%; m / n=1.1 PFPE peroxide (2) Mn=37800g / mol; PO=1.47%; m / n=1.1 PFPE peroxide (3) Mn=25000g / mol; PO=1.34%; m / n=1.1 PFPE peroxide (4) Mn=39000g / mol; PO=1.54%; m / n=1.0 PFPE peroxide (5) Mn=46000g / mol; PO=1.61%; m / n=1.0 PFPE peroxide (6) Mn=47000g / mol; PO=1.61%; m / n=1.0 PFPE peroxide (7) Mn=37000g / mol; PO=1.53%; m / n=1.0

[0067] The following items were purchased by Anles LLC and are being used as is: Perfluoroallyl (PFAA) CF₂=CFCF₂OCF₂CF₂COOH Perfluoroallyl chlorofluorocarbon (PFAAF) CF₂=CFCF₂OCF₂CF₂COF Perfluorinated vinyl cyanide (8-CNVE) CF 2=CFOCF 2CF(CF 3)OCF 2CF 2CN

[0068] The perfluorinated solvents Galden SV70, Galden HT200 and Galden D100 were obtained from Solvay Specialty Polymers, Italy.

[0069] [method:]

[0070] 19F-NMR - The structure, molecular weight, and chain-end composition of the perfluoropolyether oil were obtained using a Varian Mercury 200 MHz spectrometer working with the 19F core. 19F-NMR spectra were obtained on pure samples using CFCl3 as an internal standard.

[0071] Peroxide content (PO) is expressed as grams of oxygen peroxide per 100 g of polymer. Peroxide content was analyzed by iodometric titration using a Mettler DL40 apparatus equipped with a platinum electrode. The sensitivity limit for PO determination is 0.0002%.

[0072] [Example] [1 –] [Preparation of polycarboxylated perfluoropolyethers via thermal route] [] []

[0073] 150 g of perfluoropolyether peroxide oil [PFPE(1)], 3.4 g of PFAA, and 100 g of Galden® HT200 were introduced into a flask equipped with a magnetic stirrer and a thermometer. The mixture was heated at 80 °C to homogenize, and then the temperature was gradually increased from 160 °C to 230 °C for 14 hours under a N2 atmosphere. Finally, the product was held at 240 °C under vacuum for 1 hour. 19F-NMR analysis of the product confirmed the complete removal of peroxide units and unreacted olefins. Discovered structural system: Where m / n = 1.1, a = 3.3, as the average. X and X' = -CF 3, -CF 2COF, and Number average molecular weight (Mn) = 43,300 g / mol.

[0074] [Example] [2 –] [Preparation of polycyano-based perfluoropolyethers via photochemical route] [] []

[0075] The 800 mL cylindrical photochemical reactor is equipped with a high-pressure mercury lamp, model HANAU TQ150. The reactor is also equipped with thermocouples and a condenser.

[0076] 250 g of perfluoropolyether peroxide oil [PFPE(2)] was added together with 680 g of Galden® SV70 and 8.6 g of 8-CNVE, and stirred to obtain a homogeneous mixture. The UV lamp was turned on. During the reaction time, the reactor was kept at approximately 10°C with an ice / water mixture. The reaction was carried out under an inert N2 atmosphere. After 96 hours, the light was turned off and the reaction mixture was recovered. The solvent was then distilled under vacuum at 70°C. 19F-NMR analysis of the product confirmed the complete removal of the peroxide unit and the following structure: Where m / n = 1.1, a = 2.5, as the average. X and X' = -CF3, -CF2COF, and Number average molecular weight (Mn) = 39,500 g / mol.

[0077] The introduction of the -CN functional group was also confirmed by FT-IR spectroscopy, and the existence of the peak at 2269 cm⁻¹ was confirmed.

[0078] [Example] [3 –] [Preparation of polycarboxylated perfluoropolyethers via photochemical route] [] []

[0079] The 1000 mL cylindrical photochemical reactor is equipped with a high-pressure mercury lamp, model HANAU TQ150. The reactor is also equipped with thermocouples and a condenser.

[0080] 780 g of perfluoropolyether peroxide oil [PFPE(3)] and 776 g of PFAA were charged into a reactor and the mixture was stirred to homogenize. The reaction was carried out under a N2 atmosphere. A UV lamp was turned on. During the reaction time, the reactor was kept at approximately 20°C with an ice / water mixture.

[0081] After 36 hours, the lights were turned off, and the reaction mixture was transferred to a flask equipped with a magnetic stirrer and a thermometer. Residual PO and unreacted olefins were removed by heating the mixture from 160°C to 240°C over 11 hours.

[0082] 19F-NMR analysis of the product confirmed the complete removal of peroxide units and unreacted olefins.

[0083] The following procedure is used to convert fluoropolymer end groups into the corresponding carboxylic acids via hydrolysis.

[0084] The product was dissolved in 820 g of Galden® SV70, and 300 g of 20% HCl in water was added. The mixture was heated at 80 °C for 2 h, and then the two phases were separated at room temperature. The fluorinated phase was washed twice with 300 mL of 20% HCl and then distilled under vacuum at 120 °C to remove water and trace amounts of HCl. The final product (794 g) was analyzed by 19F-NMR, which confirmed that all fluoro groups were converted to their corresponding carboxylic acid groups.

[0085] 19F-NMR analysis confirmed the desired structure as follows: in m / n = 1.1, a = 18, as the average. X and X' = -CF3, -CF2COOH.

[0086] [Example] [4 –] [Preparation of low-equivalent-weight polycarboxylated perfluoropolyethers via thermal route] [] []

[0087] 750 g of perfluoropolyether peroxide oil [PFPE(4)] and 750 g of PFAA were introduced into a flask equipped with a magnetic stirrer and a thermometer. The mixture was heated at 80 °C to homogenize, and then the temperature was increased from 160 °C to 220 °C over 25 hours. Finally, the product was held in a vacuum at 220 °C for 1 hour.

[0088] The fluoro group is converted into the corresponding carboxylic acid by water hydrolysis.

[0089] The product was stirred with 300 g of distilled water at room temperature for 4 hours. The fluorinated product was separated from the aqueous phase and washed twice with fresh water. The final product was dried at 150 °C in a vacuum apparatus and recovered. The final product was analyzed by 19F-NMR, which confirmed that all fluoro groups were converted to the corresponding carboxylic acid groups and that all peroxide bonds were successfully removed.

[0090] Structural system: Where m / n = 1.0, a = 24, as the average. X and X' = -CF3, -CF2COOH.

[0091] [Example] [5 –] [Preparation of polyfluoropolyethers via photochemical route] [] []

[0092] The 800 mL cylindrical photochemical reactor is equipped with a high-pressure mercury lamp, model HANAU TQ150. The reactor is also equipped with thermocouples and a condenser.

[0093] Under an inert N2 atmosphere, 207 g of perfluoropolyether peroxide oil [PFPE(5)] was loaded into the reactor along with 554 g of Galden® D100 as a solvent and 199 g of PFAAF. The mixture was thoroughly stirred to homogenize. The UV lamp was turned on. During the reaction time, the reactor was kept at approximately 20°C with an ice / water mixture.

[0094] After 25 hours, the light was turned off, and the reaction mixture was returned to a flask equipped with a magnetic stirrer and thermometer under a dry N2 atmosphere. Residual PO and unreacted olefins were removed by heating the flask from 130°C to 230°C. Finally, the last trace amounts of PO were removed under vacuum at 230°C.

[0095] 19F-NMR analysis confirmed the complete removal of the peroxide unit and unreacted olefins, as well as the following structure: Where m / n = 1.0, a = 33, as the average. X and X' = -CF 3, -CF 2COF, and Number average molecular weight (Mn) = 40,200 g / mol.

[0096] [Example] [6 –] [Preparation of polycyano-based perfluoropolyethers via photochemical route] [] []

[0097] The 1000 mL cylindrical photochemical reactor is equipped with a high-pressure mercury lamp, model HANAU TQ150. The reactor is also equipped with thermocouples and a condenser.

[0098] 352 g of perfluoropolyether peroxide oil [PFPE(6)] was added together with 1180 g of Galden® D100 and 212.8 g of 8-CNVE, and stirred to obtain a homogeneous mixture. The UV lamp was turned on. During the reaction time, the reactor was kept at approximately 20°C with an ice / water mixture. The reaction was carried out under an inert N2 atmosphere.

[0099] After 56 hours, the light was turned off and the reaction mixture was recovered. The mixture was then introduced into a flask and the solvent and unreacted olefins were distilled under vacuum at 120°C.

[0100] 19F-NMR analysis of the product confirmed the complete removal of the peroxide unit and unreacted olefin, as well as the following structure: in m / n = 1.0, a = 52, as the average. X and X' = -CF 3, -CF 2COF, and Number average molecular weight (Mn) = 56,400 g / mol.

[0101] The introduction of the -CN functional group was also confirmed by FT-IR spectroscopy, and the presence of a peak at 2269 (sharp) cm⁻¹ was confirmed.

[0102] [Example] [7 –] [Preparation of polycarboxylated perfluoropolyethers via photochemical route] [] []

[0103] 250 g of perfluoropolyether peroxide oil [PFPE(7)] was charged into the reactor along with 680 g of Galden® SV70 and 5.7 g of PFAA, and the mixture was stirred to homogenize. The reaction was carried out under an inert N2 atmosphere. The UV lamp was turned on. During the reaction time, the reactor was kept at approximately 10°C with an ice / water mixture.

[0104] After 6 hours, the light was turned off and the reaction mixture was recovered. The product was introduced into a flask equipped with a magnetic stirrer and distilled to remove the solvent. The temperature was then raised to 240°C and maintained for 5 hours. 19F-NMR analysis of the product confirmed complete removal of the peroxide unit.

[0105] The fluoropolymer groups were converted to their corresponding carboxylic acids by hydrolysis with water. The product was stirred with 300 g of distilled water at room temperature for 4 hours. The final product was separated from the aqueous phase and washed twice with fresh water. The final product was then recovered after drying in a vacuum at 150 °C. 19F-NMR analysis of the final product confirmed that all the fluoropolymer groups were converted to their corresponding carboxylic acid groups.

[0106] Discovered structural system , Where Mn = 40 400 g / mol m / n = 1.0 and a = 3.5, as the average value X and X' = -CF3, -CF2COOH.

Claims

1. A block copolymer [copolymer (P)] comprising first and second perfluoropolyether chains [PFPE chains] each having two ends, wherein the first end of each of the first and second PFPE chains is an end of the copolymer (P), and each end comprises a group selected from a perfluorinated linear or branched alkyl chain having 1 to 6 carbon atoms and -C(=O)F, and the second ends of the first and second PFPE chains are bonded to each other by blocks having formula (I): wherein z is an integer from 1 to 100, (A) is the PFPE chain, and (B) is a group having formula (II): wherein n is an integer from 1 to 5; R1 to R4 are each independently selected from the group consisting of: -F, perfluorinated linear or branched alkyl chains having 1 to 6 carbon atoms, and groups having formula (III): wherein R10 is a linear or branched perfluoroalkyl chain having 1 to 12 carbon atoms, containing at least one oxygen atom, X is a functional group selected from: -COOH, -COF, -CN, -Br and -CONH2; and b is an integer equal to 1 or 2; wherein * in formula (I), (A) and (B) are arranged in a random (irregular) manner; * in formula (II), at least one of R1 to R4 has a group of formula (III); and * the total number of groups B in the copolymer (P) is from 1 to 100.

2. The copolymer (P) as claimed in claim 1, wherein, At least one of the two chain ends contains the group -C(=O)F, and the other chain end contains a perfluorinated alkyl chain containing 1 to 3 carbon atoms.

3. The copolymer (P) as claimed in claim 1 or 2, wherein, - The at least one block (A) is bonded to a chain end and / or the at least one block (B) by a σ bond or a group selected from -CF2-, -CF2CF2- or -O- by a group selected from -CF2-, -CF2CF2- or -O- by a group selected from -CF2-, -CF2CF2- or -O- by a group selected from -CF2-, -CF2CF2- or -O- by a group selected from -CF2-, -CF2CF2- or -O- by a group selected from -CF2- or -C- by a group selected from -CF2-, -CF2CF2- or -O- by a group selected from - ...O- by a group selected from -CF2- or -O- by a group selected from 4. The copolymer (P) as claimed in claim 1 or 2, wherein, Each of the PFPE chains is a fully fluorinated chain [chain (Rf)] comprising repeating units R°, which are independently selected from the group consisting of: (i) -CFXO-, wherein X is -F or -CF3; (ii) -CFXCFXO-, wherein X is the same or different each time it appears, and is -F or -CF3, provided that at least one of the X is -F; (iii); (iv); (v) -(CF2)j-CFZ-O-, wherein j is an integer from 0 to 3 and Z has a group of the general formula -OR(fa)-T, wherein R(fa) comprises a fluorinated polyoxyalkylene chain comprising 0 to 10 repeating units, which are selected from the group consisting of: -CFXO-, -CF2CFXO-, -CF2CF2CF2O-, -CF2CF2CF2CF2O-, wherein each X is independently -F or -CF3 and T is a C1-C3 perfluoroalkyl chain.

5. The copolymer (P) as claimed in claim 1 or 2, wherein: - In formula (II), at least one of the substituents R1 to R4 has a group of formula (III), and the other substituents are each independently selected from -F or a perfluorinated alkyl chain having 1 to 3 carbon atoms; and / or - in formula (III), b is a 1; and / or - in formula (III), the R10 group comprises a straight-chain or branched perfluorinated alkyl chain having 1 to 9 carbon atoms and one or two oxygen atoms.

6. The copolymer (P) as claimed in claim 5, wherein, The R10 conforms to the following formula: where d is zero or 1, and RCF is a straight-chain or branched perfluoroalkyl chain containing 1 to 3 carbon atoms, or a straight-chain or branched perfluoroalkyl chain containing 1 to 6 carbon atoms and at least one oxygen atom.

7. The copolymer (P) as claimed in claim 1 or 2, wherein, Block (I) conforms to the following formula (Ia): -[A-(B1)n1-(B2)n2-(Bx)nx]z- (Ia) where each of z and A is as defined in claim 1, each of B1, B2 and Bx is a group having formula (II) as defined in claim 1, and wherein * B1, B2 and Bx are randomly arranged within block (I), and * each of n1, n2 and nx is zero or an integer from 1 to 5, provided that at least two of n1, n2 and nx are not zero.

8. A mixture [mixture (P)] comprising two or more copolymers (P) as defined in any one of claims 1 to 7.

9. A method [method (P)] for manufacturing a copolymer (P) as defined in any one of claims 1 to 7 or a mixture (P) as defined in claim 8, said method comprising (a) contacting: - at least one perfluoropolyether polymer [PFPE peroxide] containing a peroxy group; - at least one perfluorinated compound having the formula (Xp): wherein each of R21 to R23 is independently -F, or a perfluorinated straight-chain or branched alkyl chain having 1 to 6 carbon atoms, and R10, X, and b are as defined in claim 1; (b) reacting the PFPE peroxide and the compound having the formula (Xp) in the presence of UV radiation or under heating.

10. As in the method (P) of request item 9, wherein: - The PFPE peroxide system is a perfluoropolyether polymer with two chain ends, each chain end containing a group selected from a straight-chain or branched perfluoroalkyl chain or -C(=O)F containing 1 to 6 carbon atoms, the two chain ends being bonded to opposite sides of a perfluoropolyether chain [chain (Rf)] containing repeating units (R°), such repeating units being independently selected from the group consisting of formulas (i) to (v) as defined in claim 4 and having a peroxide content (PO) between 0.1 and 4, the peroxide content being defined as the number of grams of active oxygen (Mw = 16) in 100 g of PFPE peroxide; and / or - the at least one compound having formula (Xp) is selected from: .

11. A block copolymer [polymer (PF)] comprising first and second perfluoropolyether chains [PFPE chains] each having two ends, wherein the first end of each of the first and second PFPE chains is an end of the copolymer (PF), and each end comprises a group selected from: a perfluorinated linear or branched alkyl chain having 1 to 6 carbon atoms; -COOH and its salts with organic or inorganic cations; -COOR, wherein R comprises a linear or branched alkyl chain having 1 to 6 carbon atoms; -COF; -CONH2; -CON(R100)(R101), wherein each of R100 and R101 has the same meaning as defined for R; -(R)cOH, wherein c is 0 or 1, and R is as defined above; -C(O)-OC(O)R, wherein R is as defined above. The premise is that (i) at least one end of the first and second PFPE chains contains a group different from a perfluorinated straight-chain or branched alkyl chain having 1 to 6 carbon atoms; and (ii) when one end contains the group -COF, the other end does not contain a perfluorinated straight-chain or branched alkyl chain having 1 to 6 carbon atoms or -COF; and the second ends of the first and second PFPE chains are bonded to each other by blocks having formula (I): where z is an integer from 1 to 100, (A) is a PFPE chain, and (B) is a group having formula (II): where n is an integer from 1 to 5; R1 to R4 are each independently selected from the group consisting of: -F, a perfluorinated straight-chain or branched alkyl chain having 1 to 6 carbon atoms, and a group having formula (III): where R10 is a straight-chain or branched perfluorinated alkyl chain having 1 to 12 carbon atoms, which may contain at least one or more oxygen atoms as needed. The X-series functional groups are selected from: -COOH and its salts with organic or inorganic cations; -COOR, wherein the R-series comprises a straight-chain or branched alkyl chain of 1 to 6 carbon atoms; -COF; -CON(R100)(R101), wherein each of R100 and R101 comprises a hydrogen atom or has the same meaning as defined for R; -(R)cOH, wherein c comprises 0 or 1, and the R-series comprises a straight-chain or branched alkyl chain of 1 to 6 carbon atoms; -C(O)-OC(O)R, wherein the R-series comprises a straight-chain or branched alkyl chain of 1 to 6 carbon atoms; -Br; -CN; and b comprises an integer equal to 1 or 2; wherein * in formula (I), the (A) and (B) systems are arranged in a random (irregular) manner; * in formula (II), at least one of R1 to R4 comprises a group of formula (III); and * the total number of groups B in the copolymer (PF) is from 1 to 100.

12. A mixture [mixture (PF)] comprising two or more copolymers (PF) as defined in claim 11.

13. A block copolymer [copolymer (PO-O)] comprising first and second perfluoropolyether chains [PFPE chains] conforming to formula A or (RfO-O), wherein A is as defined above, and (RfO-O) is a repeating unit conforming to any one of formulas (i) to (v) as defined for (R°) in claim 4 and having a peroxide content (PO) between 0.1 and 4, the peroxide content being defined as the number of grams of active oxygen (Mw = 16) in 100 g of PFPE peroxide, each of the first and second PFPE chains having two ends, wherein the first end of each of the first and second PFPE chains is an end of the copolymer (P), and each end comprises a group selected from: a perfluorinated linear or branched alkyl chain having 1 to 6 carbon atoms; -COOH and its salts with organic or inorganic cations; -COOR, wherein R is a linear or branched alkyl chain having 1 to 6 carbon atoms; -COF; -CONH2; -CON(R100)(R101), wherein each of R100 and R101 has the same meaning as defined for R; -(R)cOH, wherein c is 0 or 1, and R is as defined above; -C(O)-OC(O)R, wherein R is as defined above; and the second ends of the first and second PFPE chains are bonded to each other by blocks having the formula (IO-O): wherein z, A, B are as defined in claim 1, and (RfO-O) is as defined above, wherein * in formula (IO-O), A, B and (RfO-O) are arranged in a systematic (irregular) manner, and * the total number of groups B in the copolymer (PO-O) is from 1 to 100.

14. A mixture [mixture (M1)] comprising at least one copolymer (P) as defined in claims 1 to 7 and at least one of the PFPE peroxides as defined in claim 10 and / or one or more of the copolymers (PO-O) as defined in claim 13.

15. A block copolymer [polymer (PF-OO)] comprising first and second perfluoropolyether chains [PFPE chains] conforming to formula A or (RfO-O), wherein A is as defined in claim 1, and (RfO-O) is a repeating unit conforming to any one of formulas (i) to (v) as defined in claim 4 and having a peroxide content (PO) between 0.1 and 4, the peroxide content being defined as the number of grams of active oxygen (Mw = 16) in 100 g of PFPE peroxide, each of the first and second PFPE chains having two ends, wherein the first end of each of the first and second PFPE chains is an end of the copolymer (PF-OO), and each end comprises a group selected from: a perfluorinated linear or branched alkyl chain having 1 to 6 carbon atoms; -COOH and its salts with organic or inorganic cations; -COOR, wherein R is a linear or branched alkyl chain having 1 to 6 carbon atoms; -COF; -CONH2; -CON(R100)(R101), wherein each of R100 and R101 has the same meaning as defined for R; -(R)cOH, wherein c is 0 or 1, and R is as defined above; -C(O)-OC(O)R, wherein R is as defined above; The premise is that (i) at least one end of the first and second PFPE chains contains a group different from a perfluorinated straight-chain or branched alkyl chain having 1 to 6 carbon atoms; and (ii) when one end contains the group -COF, the other end does not contain a perfluorinated straight-chain or branched alkyl chain or -COF having 1 to 6 carbon atoms; and the second ends of the first and second PFPE chains are bonded to each other by blocks having the formula (IO-O): z, A, B are as defined in claim 1, and (RfO-O) is as defined above, wherein * In formula (IO-O), A, B and (RfO-O) are arranged in a systematic (random) manner, and the total number of groups B in the copolymer (PF-OO) ranges from 1 to 100.

16. A mixture [mixture (M2)] comprising at least one copolymer (PF) as defined in claim 11, and at least one of the copolymers (P) as defined in claims 1 to 7, the PFPE peroxide as defined in claim 10, the one or more copolymers (PO-O) as defined in claim 13, and / or the one or more copolymers (PF-OO) as defined in claim 15.