Fluorinated monomers comprising anthracene moieties

Related applications

[0001] This application claims priority to U.S. provisional application No. US 62/634,419, filed on February 23, 2018 and to European patent application No. EP 18161622.8, filed on March 13, 2018, the whole content of each of these applications being incorporated herein by reference for all purposes.

Technical Field

[0002] The present disclosure relates to fluorinated monomers comprising anthracene moieties, able to undergo a cycloaddition reaction under UV light. The present disclosure also relates to a process for manufacturing the fluorinated monomers. The present disclosure also relates to the adducts obtained from the fluorinated monomers, as well as to the process for preparing the adducts.

Background Art

[0003] Stimuli-responsive materials, also called sometimes smart polymers, are defined as materials which can change their properties under specific conditions, for example humidity, pH, UV light or heat. Stimuli-responsive polymers are for example used in drug delivery. As an example, conformational changes in water permeability under acid / basic pH conditions can be exploited to design carriers for drugs to be released at a desired body location. Stimuli-responsive polymers are also used in biomedical engineering. Smart polymers sensitive to UV light can be used, for example, as shape-memory materials for the manufacture of stents, as self-healing materials and for the manufacture of medical implants.

[0004] An object of the present invention is to provide a smart material which can undergo crosslinking or chain extension under specific conditions so as to generate a stable product, for the preparation of coatings, films and shaped articles in general.

[0005] Another object of the present invention is to provide a smart material which, when in the form of a crosslinked product or a chain extended product, can easily be recycled under specific conditions, without the need of chemicals.

Summary of invention

[0006] The present invention is directed to a fluorinated monomer comprising anthracene moieties. More precisely, the monomer is according to formula (I):

T ^A -0-R _f -T ^A (I)

wherein

- R _f is a (per)fluoropolyoxyalkylene chain comprising recurring units having at least one catenary ether bond and at least one fluorocarbon moiety, Rf being according to formula (III):

-(CF2CF20)a”(CF20)b”(CF2(CF2)zCF ₂ 0)c”- (III)

wherein:

- z is 1 or 2; and

- a”, b”, c” are integers > 0;

- T ^A and T ^A ’, equal to or different from each other, are selected from the group consisting of:

(i) C1-C24 (hydro)(fluoro)carbon groups, possibly comprising one or more than one of H, O, and Cl; and

(ii) (hydro)(fluoro)carbon groups comprising at least an anthracene moiety (anthracene group) of formula (II):

wherein - R is a halogen atom or an alkyl group, optionally branched, preferably an C1-C18 alkyl group optionally substituted with one or several halogen atoms; and

- n is 0 or an integer from 1 to 9, preferably 0 ;

with the proviso that at least one of T ^A and T ^A ’ comprises an anthracene moiety according to formula (II).

[0007] The present invention is also directed to a process for manufacturing the fluorinated monomer comprising anthracene moieties, possibly substituted with Rn as above defined.

[0008] The present invention is also directed to adducts obtained from exposing at least the monomers of the present invention to UV light at a wavelength ranging from 280 nm to 600 nm, as well as to the process to prepare these adducts.

[0009] The present invention is also directed to polymer blends comprising at least 1 mol.% of the monomers of the present invention.

Description of embodiments

[0010] The present invention relates to a monomer is according to formula (I):

T ^A -0-R _f -T ^A (I)

wherein

- R _f is a (per)fluoropolyoxyalkylene chain comprising recurring units having at least one catenary ether bond and at least one fluorocarbon moiety, Rf being according to formula (III):

-(CF2CF20)a”(CF20)b”(CF2(CF2)zCF ₂ 0)c”- (III)

wherein:

- z is 1 or 2; and

- a”, b”, c” are integers > 0;

- T ^A and T ^A ’, equal to or different from each other, are selected from the group consisting of:

(i) C1-C24 (hydro)(fluoro)carbon groups, possibly comprising one or more than one of H, O, and Cl; and (ii) (hydro)(fluoro)carbon groups comprising at least an anthracene moiety

(anthracene group) of formula (II):

wherein

- R is a halogen atom or an alkyl group, optionally branched, preferably an C1-C18 alkyl group optionally substituted with one or several halogen atoms; and

- n is 0 or an integer from 1 to 9, preferably 0;

with the proviso that at least one of T ^A and T ^A ’ comprises an anthracene moiety according to formula (II).

[0011] The new fluorinated monomers of the present invention comprise anthracene moieties, which are able to undergo adduct formation under certain stimuli. The reaction is induced by UV light and is reversible under different UV light frequencies. The reaction is also thermally reversible, for example microwave reversible.

[0012] These new monomers can be used to obtain films, coatings and shaped articles in general. Exposed to UV light, the monomers form adducts. As used herein, the term“adduct” means the addition product of at least two monomers of the present invention, with or without the elimination of a by- product. Adducts containing unreacted anthracene moieties can react further to form larger adducts. The so-obtained adducts can be degraded and recycled without the addition of other chemicals, but by selecting conditions to induce either complete or partial conversion of the adducts back into monomers or into smaller adducts.

[0013] Monomer of formula (I)

[0014] According to a first aspect of the invention, the present invention relates to a monomer of formula (I):

T ^A -0-R _f -T ^A (I)

wherein - R _f is a (per)fluoropolyoxyalkylene chain comprising recurring units having at least one catenary ether bond and at least one fluorocarbon moiety, Rf being according to formula (III):

-(CF2CF20)a”(CF20)b”(CF2(CF2)zCF ₂ 0)c”- (III)

wherein:

- z is 1 or 2; and

- a”, b”, c” are integers > 0;

- T ^A and T ^A ’, equal to or different from each other, are selected from the group consisting of:

(i) C1-C24 (hydro)(fluoro)carbon groups, possibly comprising one or more than one of H, O, and Cl; and

(ii) (hydro)(fluoro)carbon groups comprising at least an anthracene moiety

(anthracene group) of formula (II):

wherein

- R is a halogen atom or an alkyl group, optionally branched, preferably an C1-C18 alkyl group optionally substituted with one or several halogen atoms; and

- n is 0 or an integer from 1 to 9, preferably 0;

with the proviso that at least one of T ^A and T ^A ’ comprises an anthracene moiety according to formula (II).

[0015] According to an embodiment of the present invention, the monomer of the present invention is according to formula (IV):

T ^B -0-R _f -T ^B (IV)

wherein

- R _f is according to formula (III):

-(CF2CF20)a”(CF20)b”(CF2(CF2)zCF ₂ 0)c”- (III)

wherein z is 1 or 2; and a”, b”, c” are integers ³ 0;

- T ^B and T ^B ’, equal to or different from each other, are selected from the group consisting of: mi

(i) a group of any of formulas -CF3, -CF2CI, -CF2CF3, -CF(CF3)2, -CF2FI, -CFH ₂ , -CF ₂ CH _3J -CF ₂ CHF _2J -CF ₂ CH ₂ F, -CFZ*CH ₂ OH, -CFZ*COOH, -CFZ*COORi and -CFZ*-CH ₂ (OCH ₂ CH ₂ ) _k -OH, wherein k is ranging from 0 to 10, wherein Z ^* is F or CF3; Ri is a C ₁ -C6 hydrocarbon chain; and

(ii) (hydro)(fluoro)carbon groups comprising at least an anthracene moiety

(anthracene group) of formula (II):

wherein

- R is a halogen atom or an alkyl group, optionally branched, preferably an C1-C18 alkyl group optionally substituted with one or several halogen atoms; and

- n is 0 or an integer from 1 to 9, preferably 0;

with the proviso that at least one of T ^B and T ^B ’ comprises an anthracene moiety according to formula (II).

[0016] According to an embodiment of the present invention, the monomer of the present invention is according to formula (V):

T ^c -0-(CF ₂ CF ₂ 0) _a’ (CFY0) _b’ (CF ₂ CFY0) _c’ (CF ₂ 0) _d’ (CF ₂ (CF ₂ )zCF ₂ 0) _e’ -T ^C ’ (V) wherein:

- Y is a C ₁ -C ₅ perfluoro(oxy)alkyl group;

- z is 1 or 2;

- a’, b’, c’, d’, e’ are integers > 0;

- each of T ^c and T ^c ’, equal to or different from each other, are selected from the group consisting of:

(i) a group of any of formulas -CF3, -CF2CI, -CF2CF3, -CF(CF3)2, -CF2FI, -CFH ₂ , -CF2CH3, -CF2CHF2, -CF2CH2F, -CFZ*CH ₂ OH, and -CFZ*-CH ₂ (OCH ₂ CH ₂ ) _k -OH, wherein k is ranging from 0 to 10, wherein Z* is F or CF3; and

(ii) (hydro)(fluoro)carbon groups comprising at least an anthracene moiety (anthracene group) of formula (II):

wherein

- R is a halogen atom or an alkyl group, optionally branched, preferably an C1-C18 alkyl group optionally substituted with one or several halogen atoms; and

- n is 0 or an integer from 1 to 9, preferably 0;

with the proviso that at least one of T ^c and T ^c ’ comprises an anthracene moiety according to formula (II).

[0017] According to an embodiment of the present invention, n in formula (II) equals 0. In other words, the anthracene moieties are unsubstituted.

[0018] The chain (Rf) may be selected so as to possess a number average molecular weight (Mn) ranging from 400 to 10,000 g/mol, preferably of 750 to 10,000 g/mol, even more preferably of 1 ,000 to 8,000 g/mol, as determined by NMR.

[0019] The monomers of the present invention may be provided as the reaction products of synthetic methods and raw materials used, as mixtures/blends of compounds and monomers comprising different chemical entities (e.g. differing because of the nature and length of the Rf chain), possibly comprising variable fractions of monomers wherein both chain ends are (hydro)(fluoro)carbon groups comprising at least an anthracene moiety of formula (II) (i.e. difunctional compounds/monomers) and of monomers wherein only one chain end is (hydro)(fluoro)carbon groups comprising at least an anthracene moiety of formula (II) (i.e. monofunctional compounds/monomers), possibly associated with minor amounts of side products of similar structure, but wherein both of chain ends of the Rf chain fails to be bound to anthracene moieties.

[0020] Regarding the proportion of so-called monofunctional and difunctional monomers, good results have been achieved when the monomers consist of a major amount of monomers of formula (I) [T ^A -0-R _f -T ^A ’] as above detailed, wherein both T ^A and T ^A ’ are (hydro)(fluoro)carbon groups comprising at least an anthracene moiety of formula (II) (i.e. difunctional compounds/monomers), and a minor amount of monomers of formula (I) [T ^A -0-R _f -T ^A ’] as above detailed, wherein only one of T ^A and T ^A ’ is an (hydro)(fluoro)carbon group comprising at least an anthracene moiety of formula (II), the other group being free from the anthracene moiety (i.e. monofunctional compounds/monomers).

[0021] According to an embodiment of the present invention, the functionality of the monomer is greater than 1.0, preferably greater than 1.1 , more preferably greater than 1.2.

[0022] Difunctional and monofunctional monomers may be separately and individually used in compositions. However, the monomers are generally a mixture of difunctional and monofunctional monomers. When the compound is provided as a mixture of difunctional and monofunctional monomers, the amount of difunctional monomers and monofunctional monomers may be such that the difunctional monomers are representative of at least 50 mol.%, preferably at least 55 mol.%, more preferably at least 60 mol.% of the blend of monomers. Alternatively, the amount of difunctional monomers and monofunctional monomers may be such that the monofunctional monomers are representative of at least 50 mol.%, preferably at least 55 mol.%, more preferably at least 60 mol.% of the blend of monomers.

[0023] The monomers may be purified to remove side products. In that case, minor amounts of the side products (also called non-functional compounds) are not detrimental and may be tolerated.

[0024] The side products may be of formula (XIV):

W-O-R _f -W’ (XIV)

wherein:

R _f is a chain R _f , as above detailed;

each of W and W’, equal to or different from each other, are selected from:

(i) C1-C24 (hydro)(fluoro)carbon groups, possibly comprising one or more than one of H, O, and Cl; and

(ii) a group of any of formulas -CF3, -CF2CI, -CF2CF3, -CF(CF3)2, -CF2H, -CFH ₂ , -CF2CH3, -CF2CHF2, -CF2CH2F, -CFZ ^* CH ₂ OH, -CFZ ^* COOH, -CFZ*COORh and -CFZ*-CH2(OCH2CH2)k-OH, wherein k is ranging from 0 to 10, wherein Z ^* is F or CF3; Rh is a hydrocarbon chain.

[0025] According to an embodiment, the monomer of the present invention is according to any of formulas:

wherein Rf, T ^A and T ^B are as above-defined.

[0026] Process for manufacturing the monomer of formula (I)

[0027] The present invention also relates to a process for manufacturing the monomer of the present invention, comprising the reaction of a (per)fluoropolyether precursor comprising a (per)fluoropolyoxyalkylene chain (R _f ) comprising recurring units having at least one catenary ether bond and at least one fluorocarbon moiety and possessing at least one reactive chain end, with (hydro)(fluoro)carbon compounds comprising at least an anthracene moiety of formula (II):

wherein

- R is a halogen atom or an alkyl group, optionally branched, preferably an C1 -C18 alkyl group optionally substituted with one or several halogen atoms; and

- n is 0 or an integer from 1 to 9, preferably 0.

[0028] According to an embodiment, the (per)fluoropolyether precursor is of formula (VI):

J-O-R _f -J’ (VI)

wherein:

- R _f is a (per)fluoropolyoxyalkylene chain comprising recurring units having at least one catenary ether bond and at least one fluorocarbon moiety; - each of J and J’, equal to or different from each other, are selected from the group consisting of:

(i) groups of any of formulae -CF3, -CF2CI, -CF2CF3, -CF(CF3)2, -CF2FI, -CFH _2J -CF2CH3, -CF2CHF2, -CF2CH2F, -CFZ*COOH, and -CFZ*COOR _h wherein Z ^* is F or CF3; R _h is a C ₁ -C6 hydrocarbon chain; and

(ii) hydroxyl-containing groups (groups J ^0H ) of any of formulas -CFZ*CH ₂ OH, and -CFZ*-CH ₂ (OCH ₂ CH ₂ ) _k -OH, wherein k is ranging from 0 to 10, wherein Z ^* is F or CF3 _, with the proviso that at least one of J and J’ is a group (J ^0H ).

[0029] Preferably each of J and J’, equal to or different from each other, are selected from the group consisting of:

(i) groups of any of formulas -CF3, -CF2CI, -CF2CF3, -CF(CF3)2, -CF2FI, -CFH ₂ , -CF ₂ CH3, -CF ₂ CHF ₂ , -CF ₂ CH ₂ F, -CFZ*CH ₂ OH, -CFZ*COOH, -CFZ*COOR _h and -CFZ*-CH ₂ (OCH ₂ CH ₂ ) _k -OH, wherein k is ranging from 0 to 10, wherein Z ^* is F or CF3; R _h is a hydrocarbon chain; and

(ii) hydroxyl-containing groups (groups J ^0H ) of any of formulas - CFZ*CH ₂ 0H, and -CFZ*-CH ₂ (OCH ₂ CH ₂ ) _k -OH, wherein k is ranging from 0 to 10, wherein Z ^* is F or CF3 _,

with the proviso that at least one of J and J’ is a group (J ^0H ).

[0030] According to an embodiment of the present invention, the reaction takes place at a temperature ranging from 40 to 180°C, preferably from 60 to 130°C.

[0031] According to certain embodiments, the compound of formula (XIII) can be preliminarily reacted with an activating compound/agent. The choice of the activating compound/agent is not limited, and typical organic chemistry strategies may be applied

[0032] Processes for preparing an adduct and adduct obtained therefrom

[0033] The present invention also relates to a process for manufacturing an adduct, comprising exposing the monomers of the present invention to UV light at a wavelength ranging from 280 nm to 600 nm, preferably from 300 nm to 450 nm.

[0034] The present invention also relates to an adduct obtained from this process. [0035] The present invention also relates to an adduct obtained from exposing at least the monomer of the present invention to UV light at a wavelength ranging from 280 nm to 600 nm, preferably from 300 nm to 450 nm.

[0036] The monomers of the present invention can for example be used for the manufacture of films, coatings, or shaped articles. Films can be porous or non-porous and may have a thickness ranging from 0.05 to 500 pm. They can be flat films or may have a tubular shape. Coatings may be in the form of single layers or in the form of multiple layers having a higher thickness, typically ranging from 0.1 to 1 ,000 pm and may fully or partially cover the underlying surface, which may have any shape and dimension. The coating can be formed prior to covering the surface and then applied to the surface or formed directly on the surface to be covered according to conventional methods, such as by casting a polymer or a composition on the surface and then by forming a film. Alternatively, a mixture of monomers can be casted on the surface to be coated and submitted to the conditions that allow the cycloaddition reaction to occur.

[0037] Non-limiting examples of surfaces to be coated are surfaces of polymer, metal, glass and ceramics articles, and paper or wood in the form of solid or porous fibers, woven sheets, non-woven sheets, or shaped articles.

[0038] Non limiting examples of shaped articles include solid or porous fibers, filaments, woven sheets, non-woven sheets, fuel line hoses, miniature circuit breakers (MCB), electrical switches and smart devices, surgical stents, surgical implants, and medical devices. Such articles can be manufactured according to conventional methods. In one embodiment, shaped articles can be manufactured by 3D printing techniques, including, but not limited to stereolithography (SLA). In one embodiment, the shaped composites can be manufactured by compression molding of a continuous fiber (glass, carbon) fabric using the usual processes to produce thermoset composites and thermoplastic composites, with the application of UV light when necessary.

[0039] The present invention also relates to a process for coating a surface, comprising: a) applying to the surface the monomer of the present invention or the polymer blend of the present invention, and

b) exposing the surface to UV light at a wavelength ranging from 280 nm to 600 nm, preferably from 300 nm to 450 nm.

[0040] The present invention also relates to a process for manufacturing a shaped article, comprising exposing the polymer blend of the present invention to UV light at a wavelength ranging from 280 nm to 600 nm, preferably from 300 nm to 450 nm.

[0041 ] Processes for recycling an article comprising the adduct

[0042] The films (or membranes), coatings or shaped articles obtained from the monomers of the present invention can be recycled by exposure to UV light at a wavelength of less than 300 nm or by exposure to heat at a temperature of at least 180°C, preferably at least 195°C.

[0043] When films (or membranes), coatings or shaped articles obtained from the monomers of the present invention are recycled by exposure to heat, different means can be used. They can for example be recycled by using microwave energy or photo-irradiation to depolymerize the monomers.

[0044] The present invention also relates to a process for recycling a coating or a shaped article comprising the polymer adduct of the present invention, by exposing the coating or the shaped article to UV light at a wavelength of less than 300 nm.

[0045] The present invention also relates to a process for recycling a coating or a shaped article comprising the polymer adduct of the present invention, by heating the coating or the shaped article at a temperature higher 180°C, preferably higher 195°C, for example by using microwave energy of photo- irradiation.

[0046] Polymer blend

[0047] The present invention also relates to a polymer blend comprising at least 1 mol.% of the monomers according to the present invention, for example at least 2 mol.%, at least 5 mol.%, at least 10 mol.%, at least 20 mol.%, at least 30 mol.%, at least 40 mol.% or at least 50 mol.% of the polymer blend. [0048] The polymer blends of the present invention can comprise additives for example selected from the group consisting of chopped and continuous glass fibers, chopped and continuous carbon fibers, stabilizers and pigments.

[0049] The polymer blends of the present invention can comprise at least one solvent or a mixture of solvents selected from the group consisting of:

- fluorinated solvents such as (per)fluoroethers, (per)fluoropolyethers, (per)fluoralkanes, (per)fluoroamines;

fluoroaromatics solvents such as hexafluorobenzene and hexafluoroxylene); and

- hydrogenated solvents such as THF and toluene.

[0050] Polymer blends can be manufactured according to mixing/blending methods known in the art.

[0051] Should the disclosure of any patents, patent applications, and publications which are incorporated herein by reference conflict with the description of the present application to the extent that it may render a term unclear, the present description shall take precedence.

[0052] EXAMPLES

[0053] The invention will be now described in more detail with reference to the following examples, whose purpose is merely illustrative and not intended to limit the scope of the invention.

[0054] Starting Materials

9,10-dibromo-anthracene (Apollo Scientific)

2-hydroxy-anthracen-9,10-one

9-methanol-anthracene

PFPE(OCF ₂ CH ₂ OH) ₂ (Z-DOL)

PFPE-Nonaflate (as described in WO 2017/016943)

Galden ^® Fluid HT-270, HT-110, HT-230, commercially available from Solvay Specialty Polymers

[0055] Methods

[056] ¹ H-NMR analyses were performed on a Varian Mercury 300 MFIz spectrometer using tetramethylsilane (TMS) as internal standard. [057] ¹⁹ F-NMR analyses were performed on a Varian Mercury 300 MHz spectrometer using CFC as internal standard.

[0058] UV absorption in solvent (CeFe), using a UV lamp 200 Perkin-Elmer element 3 with 1 cm length

[0059] Example 1 - Synthesis of Perfluoropolyether-bis-9-oxy-Anthracene (VIII)

PFPE(OCF ₂ CH ₂ OH) ₂ (Z-DOL; 4,905 g; 5,95 meq; EW = 824 g/eq) was slowly dripped in a glass round bottom flask equipped with an internal thermometer, a gas inlet, a reflux condenser and a dripping funnel, containing anhydrous potassium tert-butoxide (0,666 g; 5,95 mmols); the dishomogeneous mixture was let stir overnight in an inert atmosphere at 100 rpm and at 40°C. A white homogeneous, viscous paste formed which was stripped of tert-butanol by vacuum distillation at 55°C (“Z-Dol-ate”). Commercially available 9,10-dibromo-anthracene (Apollo Scientific; 2,00 g; 5,95 mmol) were dissolved in 60 ml of toluene obtaining a homogeneous, yellow solution at 50°C and were dripped in the dishomogeneous suspension of Z-DOL-ate, hexafluoroxylene (40 ml) and anhydrous DMSO (20 ml). The temperature was raised to 110°C with 900 rpm magnetic stirring and let stir for 8 hrs. During the course of the reaction the conversion was sped up by adding a total of 7,95 mmol of potassium tert- butoxide in small aliquots every 2 hours until complete conversion of Z- Dol-ate was achieved. The crude reaction mixture was then diluted in 85 ml of CH ₂ CI ₂ and extracted with 2 portions of HCI 5% w/v (40 ml/portion). The lower organic phase was collected, dried over MgS04 and filtered with a pressure filter upon a 0,45 pm PTFE filtering membrane. The dried filtrate was let stand overnight in which time unreacted starting 9,10-dibromo-anthracene precipitated (575 mg; 28,8 mol%). The filtrate was then fractionally eluted in a S1O2 gel column eluting with CH2CI2/CH3OH (97/3 v/v) to eliminate the corresponding bis-PFPE anthracenic derivative. The fractions corresponding to Perfluoropolyether- bis-9-oxy-Anthracene were collected and the solvents evaporated.

[0060] Results:

Isolated Yield = 44 mol%

MW = 1814 g/mole

EW = 992 g/eq

f = 1 ,82

Solubility: 20 w% CeF6 at 20°C

NMR:

¹⁹ F-NMR: -51 ,5; -53; -55 ppm (-OCF2-; s); -78; -80 ppm (-OCF2-Arom; s); -89,5; -91 ,5 ppm (-OCF2CF2; s)

¹ H-NMR: 8,3; 8,2; 8,0; 7,8 ppm; (Aromatics including meso ring; m); 4,6 ppm (-0CF ₂ CH ₂ -0-Ar; s).

[0061] Example 2 - Synthesis of Perfluoropolyether-bis-2-oxy-Anthracene (IX)

[0062] 2-hydroxy-anthracen-9,10-one was reduced in ethanolic sodium borohydride obtaining crude 2-hydroxy-anthracene which was purified by double sublimation. Purified 2-hydroxy-anthracene (0,300 g; 1 ,546 meq) was dissolved in 16 ml of anhydrous CH3CN and placed in a glass round bottom flask equipped with an internal thermometer, a gas inlet, a reflux condenser and a dripping funnel. The homogeneous solution was heated to 45°C and then a solution of tBuOK/tBuOH (9,25 w/v; 1 ,81 g; 1 ,546 mmol), was slowly dripped. The homogeneous yellow mixture turns almost immediately purple. The homogeneous purple solution was then maintained at 40°C with magnetic stirring at 700 rpm for 40 min. PFPE- Nonaflate (PFPE-Nf; EW = 2141 g/eq; 3,311 g; 1 ,546 meq) is diluted in 48 ml of hexafluoroxylene ad it is dripped in the 2-oxy-anthracenate, violet solution. The mixture is heated to 80°C let stir at 800 rpm for 15 hrs. Conversion is complete by spectroscopically ( ¹⁹ F-NMR) measuring the [ F9SO3K]. The crude mixture is washed twice with FtaO ⁺ CI- 7 % w/v. The organic layer is collected and dried over MgS0 ₄ . It is then filtered with a pressure filter upon a 0,45 pm PTFE filtering membrane and the solvents are evaporated under vacuum.

[0063] Results:

Isolated yield: 71 mol.%

MW = 4,816 g/mol

EW = 2,646 g/eq

f = 1 ,82

Solubility: 12 % w/v in ¼ v/v CeFe/THF.

NMR:

¹⁹ F-NMR: -52; -54; -56 ppm (-OCF2-; s); -78,5; -80,5 ppm

(-OCF ₂ -CFl ₂ 0-Arom; s); -89,0; -91 ,0 ppm (-OCF2CF2; s)

¹ H-NMR: 8,7; 8,5; 8,0; 7,7 ppm; (Aromatics including meso ring; m); 4,45 ppm (-0CF ₂ CH ₂ -0-Ar; s).

[0064] Example 3 - Synthesis of perfluoropolyether-bis-oxy-benzyl-Anthracene

(X)

[0065] Commercially available 9-methanol-anthracene (0.50 g; 2,41 mmoles) is diluted in CH2CI2 (55 ml) and placed in a round-bottomed flask equipped with a magnetic stirring bar, a reflux condenser, an internal thermometer and a dripping funnel. Air within the reactor is displaced with N2 and the mixture is maintained inert with a positive, static N2 pressure. Triethylamine (0.38 g; 3.71 mmol) is added drop-wise and then the internal reaction T is lowered to 4°C by dipping the reactor in an ice-water bath. A solution of mesyl chloride (0.44 g; 3.71 mmol) in CH2CI2 (9 ml) is dripped in the reactor, with stirring = 800 rpm, in 20 min not letting the internal T go beyond 10°C. The reactor T is then let rise to 20°C and after 3 hrs conversion to the mesylate is 100%. In order to avoid the Williamson Reaction during a protic solvent work-up, the crude mixture is stripped under vacuum to distill CH2CI2 and triethylamine away. Residual triethylammonium chloride is inert in the Williamson Reaction which will follow. In another similar glass reactor, PFPE Z-DOL (EW=824 g/mole; 3.96 g: 4.81 meq) is converted to its corresponding potassium salt by adding anhydrous potassium tert-butoxide. The Z-DOLate thus obtained is diluted with 35 ml of hexafluoroxylane at 20°C and with 900 rpm stirring, obtaining a milky suspension. The anthracene mesylate obtained above (0.73 g referred to the pure compound; 2.41 mmol) is diluted in anhydrous CH3CN (40 ml) and it is dripped in the Z-DOL-ate suspension while heating the mixture to 86°C with 1100 rpm stirring. The reaction is left at 86°C and 1100 rpm stirring for 10.5 hrs. It is then cooled to 20°C, further diluted with EFX (50 ml) and extracted with 70 ml H30+CI- (9 % w/v). The lower organic phase is collected, dried over MgS04, filtered with a 0.45 m m PTFE filtering membrane and the solvents stripped under vacuum at 65°C.

[0066] Results:

Isolated yield = 20 mol.%

MW = 1 ,818 g/mol

EW = 1515 g/eq

£370 = 2,794 M- ¹ cm- ¹ = 2,328 Eq- ¹ cm- ¹

f = 1.25 Solubility: 18 % w/w in C6F6

[0067] Example 4 - Synthesis of an adduct made of perfluoropolyether-bis-oxy- benzyl-Anthracene (X)

[0068] The C6F6 solution of monomers (X) (1 ,11 g) was placed in a Petri dish with an internal diameter = 2,5 cm and the solvent evaporated in a vacuum oven at 60°C and 800 mbar PRES for 90 min, followed by 60 min at 100°C and 800 mbar PRES. A viscous layer was obtained (200 mg; 0,891 M).

[0069] The sample was then placed in the UV irradiation machine in an inert chamber (N2; dynamic; 1 N ^* L/h) employing a glass cover in order to cut-off all l< 300 nm, thus avoiding the de-oligomerization. Puv was set at 800 W. The irradiation was performed in a manner such as not to exceed TR = 25°C. The progress of the photo-oligomerization was analysed at the irradiation times t= 9 min, t= 18 min and t= 27 min. The progress of the photo-oligomerization was monitored by UV analysis, by taking a 6.6 mg sample from the Petri dish and dissolving it in 3 ml_ of CeF6 and placing the diluted sample in a quartz cuvette (1210 mM). Calculations were performed upon the conversion (h) of the Anthracenic meso uuQ.

[0070] After 27 min of UV irradiation, q ^meso = 36.66 mol% corresponding to dimers as the major oligomeric species detected in the UV cuvette. See Table 1 below.

T

Table 1

[0071] Example 5 - Recyclability by heat - Thermo-de-Oligomerization of material obtained from perfluoropolyether-bis-oxy-benzyl-Anthracene (X) [0072] An oligomeric material obtained as described in Example 4 up to H _meso = 45.4% was then placed in a Buchi oven in an inert (N2) atmosphere and heated at various temperatures detailed in Table 3, for a total of 17 min. This experiment was performed in the presence of light.

[0073] After 17 minutes of heating, r| ^meso = g mol.%. See Table 3 below.

Table 2 - before heating

Table 3 - after heating

[0074] Example 6 - Photo-oligomerization of reclycled material by heat obtained from perfluoropolyether-bis-oxy-benzyl-Anthracene (X)

[0075] The material obtained from recyclability test by heat obtained in Example 5 was oligomerizated again by UV up to H _meso (%) = 16.9% at Tr(°C) = 20- 30°C.

Table 4

[0076] Example 7 - Recylability by UV - Photo-de-Oligomerization of material obtained from perfluoropolyether-bis-oxy-benzyl-Anthracene (X) [0077] An oligomeric material obtained as described in example 4 up to h meso (%) = 51.0 was recycled by UV. It was placed in a glass Petri dish of 3.5 cm diameter and centered upon the heated thermal plate of a Wood Light UV instrument with 6 independent UV light sources. While priming the Wood Light instrument, the irradiation chamber was purged with N2 at a rate of approximately 5 NL/h. The sample was exposed to UV light (254nm, 30 W).

[0078] After 240 minutes of UV, r| ^meso = g mol.%. See Table 5 below.

Table 5

[0079] Example 8 - Synthesis of perfluoropolyether-bis-oxy-benzyl-Anthracene

(X)

[0080] Commercially available 9-methanol-anthracene (1.0 g; 4.81 mmol) is diluted in CH2CI2 (55 ml) and placed in a round-bottomed flask equipped with a magnetic stirring bar, a reflux condenser, an internal thermometer and a dripping funnel. Air within the reactor is displaced with N2 and the mixture is maintained inert with a positive, static N2 pressure. Triethylamine (0.76 g; 7.42 mmol) is added drop-wise and then the internal reaction T is lowered to 4°C by dipping the reactor in an ice-water bath. A solution of mesyl chloride (0.88 g; 7.42 mmol) in CH2CI2 (9 ml) is dripped in the reactor, with stirring = 800 rpm, in 20 min not letting the internal T go beyond 10°C. The reactor T is then let rise to 20°C and after 3 hours conversion to the mesylate is 100%. In order to avoid the Williamson Reaction during a protic solvent work-up, the crude mixture is stripped under vacuum to distill CH2CI2 and triethylamine away and isn’t worked-up any further. Residual triethylammonium chloride is inert in the Williamson Reaction which will follow. In another similar glass reactor, PFPE Z-DOL (EW= 824 g/mol; 3.96 g: 4.81 meq) is converted to its corresponding potassium salt by adding anhydrous potassium tert-butoxide. The Z- DOLate thus obtained is diluted with 35 ml of hexafluoroxylane at 20°C and with 900 rpm stirring, obtaining a milky suspension. The anthracene mesylate obtained above (1.45 g referred to the pure compound; 4.81 mmol) is diluted in anhydrous CH3CN (50 ml) and it is dripped in the Z- DOL-ate suspension while heating the mixture to 86°C with 1100 rpm stirring. The reaction is left at 86°C and 1100 rpm stirring for 10.5 hrs. It is Then cooled to 20°C, further diluted with EFX (50 ml) and extracted with 70 ml H30 ⁺ CI- (9 % w/v). The lower organic phase is collected, dried over MgS0 ₄ , filtered with a 0.45 pm PTFE filtering membrane and the solvents stripped under vacuum at 65°C.

[0081] Results:

Isolated yield = 89 mol.%

MW = 1 ,829 g/mol

EW = 978 g/eq

£ ₃₇₀ = 4,346 M- ¹ cm- ¹ = 2,328 Eq- ¹ crrr ¹

f = 1.9

Solubility: 15.4 % w/w in CeF ₆

[0082] Example 9 - Photo-Oligomerization of perfluoropolyether-bis-oxy-benzyl- Anthracene (X)

[0083] A sample of perfluoropolyether-bis-oxy-benzyl-Anthracene (X) of example 8 was oligomerized via UV as described in Example 4, up to a h meso (%) =

57,5%.

Table 6

[0084] Example 10 - Recyclability by UV (Photo-de-Oligomerization) of perfluoropolyether-bis-oxy-benzyl-Anthracene (X) [0085] A sample of oligomeric material obtained as described in example 9 up to H _meso (%) = 57,5% was recyled by UV with same equipment and set-up of example 7, down to h meso (%) = 31 ,1 %

Table 7