Description

Reversibly cross-linkable composition of ionic polymers

Cross-reference to related applications

[0001] This application claims priority from US provisional patent application No.

62/678079 filed on 30 May 2018, the whole content of this application being incorporated herein by reference for all purposes.

Technical Field

[0002] The present invention relates to certain compositions comprising ionic polymers and anthracene derivatives, which are simultaneously able to create ionic networks and which are able to undergo a cycloaddition reaction under certain stimuli, thereby reversibly forming adducts endowed with improved or additional properties with respect to those of the starting composition.

Background Art

[0003] Present invention refers to materials interconnected by ionic bonds, so inherently possessing self-healing behavior, and further containing moieties able to undergo a cycloaddition reaction under certain stimuli.

[0004] Compositions of ionic polymers, including composition of low Tg polymers, are known in the art. For instance, WO 2013/017470 (SOLVAY SPECIALTY POLYMERS ITALY SPA) 07/02/2013 discloses compositions comprising two ionisable fluoropolymers, each comprising recurring fluorinated blocks and recurring blocks comprising at least one ionisable anionic or cationic group, wherein at least one ionizable recurring block is comprised between two fluorinated blocks, which are decribed as possessing a self-repairing behaviour. Similarly, WO 2014/090646 (SOLVAY SPECIALTY POLYMERS ITALY SPA) discloses compositions comprising: a combination of ionisable fluoropolymers, each comprising recurring fluorinated blocks and recurring blocks comprising at least one ionisable anionic or cationic group. Such compositions are stable even after addition of a cross-linking agent and can be used for the manufacture of polymeric materials endowed with high chemical stability, improved mechanical properties and, in some instances, self-healing properties.

[0005] Still, WO 2018/078001 (SOLVAY SPECIALTY POLYMERS ITALY SPA) discloses certain metal corrosion preventing compositions possessing self- healing properties based on the combination of amorphous polymers possessing ionisable end groups in substantially equimolar amount.

[0006] All these ionic supramolecular network, while possibly possessing self- repairing ability, are nevertheless not stimuli-responsive materials, which may reversibly change their properties under specific conditions, for example humidity, pH, UV light or heat.

[0007] Stimuli-responsive materials have recently attracted significant interest for their possible advantageous features in diverse fields of use including biomedical engineering, or other advanced applications.

[0008] In this area, mention can be notably made of approaches to stimuli- responsiveness described in PCT application number EP2018/055500, filed on March 2018, which describes certain polymer blends based on high performance aromatic polymers and comprising notably an anthracene

wherein:

W is a bond, or a bridging group;

R is a halogen atom or an alkyl group, optionally substituted; and

n is 0 or an integer from 1 to 9; these blends were found to reversibly form crosslinked adducts under certain light/temperature stimuli, thanks to the chemistry of the anthracene groups above depicted.

[0009] Indeed, it is known that anthracene moieties, including substituted anthracenes, are able to reversibly undergo a dimerization reaction under the action of UV radiation, forming a so-called dianthracene (or sometimes paranthracene) adduct, whereas the original anthracenes moieties have in this adduct lost its conjugated aromatic character and are connected by a pair of newly formed covalent carbon-carbon bonds, resulting from the [4+4]

cycloaddition:

[0010] The reaction can be reversed thermally or by action of UV radiation possessing wavelength of below of 300 nm.

[001 1] Now, there’s a need in the art of materials which combine the advantages of ionic supramolecular dynamic structures with that of covalent activable and reversible supramolecular bonding, so that the final properties of the materials can be tuned easily by applying external physical stimuli, while maintaining self-healing benefits.

Summary of invention

[0012] The present invention relates to a composition [composition (C)] comprising:

- at least one polymer [polymer (P1 )] comprising a polymer chain [chain (R)] consisting of a plurality of non-ionisable recurring units [units (U)], said chain having two ends, each end comprising at least one ionisable acid group;

at least one polymer [polymer (P2)] comprising a polymer chain [chain (R)] consisting of a plurality of non-ionisable recurring units [units (U)], said chain (R) being equal or different from that of polymer (P1 ) and having two ends, each end comprising at least one ionisable amino group;

- at least one anthracene compound [compound (A)] comprising at least one anthracene group and at least one ionisable group selected from ionisable acids groups and ionisable amino groups;

wherein: the ratio between the equivalents of ionisable acid groups of polymer (P1 ) and of compound (A), if any, and the equivalents of ionisable amino groups of polymer (P2) and of compound (A), if any, in said composition (C) ranges from 1.4 to 0.6, more preferably from 1.2 to 0.8, most preferably from 1 .1 to 0.9.

[0013] The Applicant has surprisingly found that the infinite ionic network originating from fast acid/base reaction can be further reversibly complemented by the reversible creation of covalent bonds through the anthracene moieties which are further ionically connected to the ionic network. More specifically, the Applicant has surprisingly found that covalent bonds uniting moieties derived from anthracene UV-induced dimerization can be broken on demand without affecting the ionic supramolecular structure nor the ionic bond of the said anthracenes to the other constituting polymeric chains, so that the viscosity and/or mechanical properties can be tuned accordingly to specific needs. Recyclability of the final materials is notably facilitated by this controlled “depolymerisation”.

[0014] The present invention also relates to a supramolecular adduct obtained by exposing to UV light at a wavelength ranging from 300 nm to 600 nm, preferably from 350 nm to 400 nm the composition (C), as above detailed.

[0015] The present invention relates to a method for coating a surface, comprising: a) applying to the surface the composition (C), as detailed above,

optionally in combination with one or more solvents and/or additives, b) irradiating the surface at a wavelength ranging from 300 nm to 600 nm, preferably from 350 nm to 400 nm.

[0016] The present invention relates to a method for manufacturing a formed article, comprising:

a) filling a mould with a composition (C), as above detailed,

optionally in combination with one or more solvents and/or additives, b) irradiating the mould at a wavelength ranging from 300 nm to 600 nm, preferably from 350 nm to 400 nm. [0017] The present invention relates to a method for recycling a coating or a formed article, comprising the supramolecular adduct obtained by exposing to UV light at a wavelength ranging from 300 nm to 600 nm, wherein the method comprises submitting the coating or formed article to UV irradiation at a wavelengths lower than 300 nm.

[0018] The present invention also relates to a recycled material obtainable by the recycling methods of the present invention.

Brief Description of Figures

[0019] Figure 1 is a multi-dimensional map showing excitation intensity and emission intensities as a function of the wavelength as obtained using an inventive composition.

[0020] Figure 2 depicts the trend of intensity (expressed in counts) of the emission at Ae _m : 450 nm (i.e. at maximum emission wavelength) as a function of time, expressed in seconds, as obtained using an inventive composition.

[0021] Figure 3 depicts the graph of 1/c, whereas c is the concentration of the anthracene compound, as a function of time, as obtained using an inventive composition under UV irradiation.

Description of embodiments

[0022] In the present invention, by the acronym “PFPE” is meant “(per)fluoropolyether", i.e. fully or partially fluorinated polyether, i.e. wherein all or only a part of the hydrogen atoms of the hydrocarbon structure have been replaced by fluorine atoms so that a higher proportion of fluorine atoms than hydrogen atoms is contained in the structure. When this acronym is used as substantive in the plural form, it is referred to as“PFPEs”.

[0023] The term“(per)haloalkyl” denotes a fully or partially halogenated straight or branched alkyl group.

[0024] Unless otherwise indicated, the term “halogen” includes fluorine, chlorine, bromine and iodine. [0025] In the present invention, unless otherwise indicated, the following terms are to be meant as follows:

- a “cycloalkyl group” is a univalent group derived from a cycloalkane by removal of an atom of hydrogen; the cycloalkyl group thus comprises one end which is a free electron of a carbon atom contained in the cycle, which able to form a linkage with another chemical group;

- a“divalent cycloalkyl group” or“cycloalkylene group” is a divalent radical derived from a cycloalkane by removal of two atoms of hydrogen from two different carbons in the cycle; a divalent cycloalkyl group thus comprises two ends, each being able to form a linkage with another chemical group;

- the adjective“aromatic” denotes any mono-or polynuclear cyclic group (or moiety) having a number of p electrons equal to 4n+2, wherein n is 0 or any positive integer; an aromatic group (or moiety) can be an aryl or an arylene group (or moiety);

- an“aryl group” is a hydrocarbon monovalent group consisting of one core composed of one benzene ring or of a plurality of benzene rings fused together by sharing two or more neighbouring ring carbon atoms, and of one end. Non-limitative examples of aryl groups are phenyl, naphthyl, anthryl, phenanthryl, tetracenyl, triphenylyl, pyrenyl, and perylenyl groups. The end of an aryl group is a free electron of a carbon atom contained in a (or the) benzene ring of the aryl group, wherein an hydrogen atom linked to said carbon atom has been removed. The end of an aryl group is capable of forming a linkage with another chemical group;

- an“arylene group” is a hydrocarbon divalent group consisting of one core composed of one benzene ring or of a plurality of benzene rings fused together by sharing two or more neighbouring ring carbon atoms, and of two ends. Non-limitative examples of arylene groups are phenylenes, naphthylenes, anthrylenes, phenanthrylenes, tetracenylenes, triphenylylenes, pyrenylenes, and perylenylenes. An end of an arylene group is a free electron of a carbon atom contained in a (or the) benzene ring of the arylene group, wherein a hydrogen atom linked to said carbon atom has been removed. Each end of an arylene group is capable of forming a linkage with another chemical group.

[0026] Cycloalkyl, cycloalkylene, aryl and arylene groups can be substituted with one or more straight or branched alkyl or alkoxy groups and/or halogen atoms and/or can comprise one or more heteroatoms, like nitrogen, oxygen and sulphur, in the ring.

[0027] The use of parentheses“(...)”before and after names of compounds, symbols or numbers identifying formulae or parts of formulae like, for example “polymer (P1 )”, “chain (R)”, etc..., has the mere purpose of better distinguishing those names, symbols or numbers from the rest of the text; thus, said parentheses could also be omitted.

[0028] When ranges are indicated, range ends are included.

[0029] The expression“as defined above” is intended to comprise all generic and specific or preferred definitions referred to by that expression in preceding parts of the description, unless indicated otherwise.

[0030] The expression“ionisable amino group” and“ionisable acid groups” identify amino or acid groups able to form ionic groups, namely cationic and anionic groups respectively. In greater detail, an ionisable amino group identifies a primary, secondary or tertiary amino group, while an“ionisable acid group” identifies an acid group comprising at least one hydroxyl function in its protonated form, i.e. a protic acid group.

[0031] The expression“non-ionisable recurring unit” identifies a chemical moiety that is not able to form an ionic group with the at least one ionisable amino group or the at least one ionisable acid group in each end of polymers (P1 ) and (P2).

[0032] Polymers (P1 ) and (P2) are generally amorphous polymers, that is to say that they possess a heat of fusion of less than 5 J/g, preferably less than 3 J/g, more preferably less than 1 J/g, when determined by DSC technique according to ASTM D3418.

[0033] Generally, polymers (P1 ) and (P2) have a glass transition temperature (T _g ) of lower than -35°C, preferably ranging from -35°C to -120°C, whereas T _g is determined by DSC according to ASTM D3418 at midpoint with a scan rate of 20°C/min.

[0034] Such T _g requirement is a particularly advantageous feature for enabling the three-dimensional network formed by polymer (P1 ) and polymer (P2) to cope with the requirements of a flexible or adaptative coating and/or for imparting overall flexibility to the resulting ionically networked material.

[0035] POL YMER (P1)

[0036] Polymer (P1 ) can be represented with formula (P1 ) here below:

(P1) E1 -R-E1’

wherein:

- R is a polymer chain consisting of a plurality of non-ionisable recurring units [units (U)], equal to or different from one another and

- E1 and E1’, equal to or different from one another, are end groups each comprising at least one ionisable acid group. Recurring units (U) are hydrocarbon units, which can further comprise non-ionisable atoms or non- ionisable functional groups, including one or more of halogen atoms, preferably fluorine atoms, ethereal oxygen atoms, alkyl or alkoxy silane groups, carbonate, ester, urethane and acrylate groups.

[0037] Non limiting examples of polymers (P1 ) are those wherein chain (R) is independently selected from a fully or partially fluorinated polyoxyalkylene chain, a polyalkylsiloxane chain, a polyoxyalkylene chain, a polycarbonate chain, a polyester chain, a polyacrylate chain and a polybutadiene chain, as described in greater detail here below.

[0038] Examples of chains (R)

[0039] Fully or partially fluorinated polyoxyalkylene chains (RF)

[0040] As intended herein, a fully or partially fluorinated polyoxyalkylene chain [herein after otherwise referred to as“chain (RF)”,“(per)fluoropolyether chain” or“PFPE chain”] comprises recurring units [units (UF)] having at least one catenary ether bond and at least one fluorocarbon moiety; typically, chain (RF) comprises repeating units (UF) selected from: (UF - i) -CFXO-, wherein X is F or CF ₃ ;

(UF - ii) -CFXCFXO-, wherein X, equal or different at each occurrence, is F or CF ₃ , with the proviso that at least one of X is -F;

(UF - iii) -CF2CF2CW2O-, wherein each of W, equal or different from each other, is F, Cl, H,

(U _F - iv) -CF2CF2CF2CF2O-;

(UF - v) -(CF ₂ ) _j -CFZ-0- wherein j is an integer from 0 to 3 and Z is a group of general formula -OR T, wherein Rf ^* is a fluoropolyoxyalkene chain comprising a number of repeating units from 0 to 10, said recurring units being chosen among the followings : -CFXO- , -CF2CFXO-, -CF2CF2CF2O-, -CF2CF2CF2CF2O-, with each of each of X ^* being independently F or CF3 and T being a C1-C3 perfluoroalkyl group.

When recurring units [units (UF)] are different from one another, they are randomly distributed along the chain.

[0041] Preferably, chain (RF) complies with formula (RF-I):

(R _F -l) -(CFX _l 0)g _l (CFX ₂ CFX ₃ 0)g ₂ (CF ₂ CF ₂ CF ₂ 0)g ₃ (CF ₂ CF ₂ CF ₂ CF ₂ 0)g ₄ - wherein:

- Xi is independently selected from -F and -CF ₃ ;

- X2, X3, equal or different from each other and at each occurrence, are independently -F, -CF3, with the proviso that at least one of X is -F;

- g1 , g2 , g3, and g4, equal or different from each other, are independently integers ³0, selected in such a way that the average number molecular weight (Mn) ranges from 400 to 10,000; should at least two of g1 , g2, g3 and g4 be different from zero, the different recurring units are generally statistically distributed along the chain.

[0042] More preferably, chain (RF-I) is selected from chains of formulae (RF-I IA) - (RF-I IE):

(RF -IIA) -(CF ₂ CF ₂ 0) _ai (CF ₂ 0) _a2 - wherein: - a1 and a2 are independently integers ³ 0 such that the number average molecular weight (M _n ) ranges from 400 to 10,000, preferably from 400 to 5,000; both a1 and a2 are preferably different from zero, with the ratio a1/a2 being preferably ranging from between 0.1 to 10;

(RF-I IB) -(CF2CF20)bi(CF20)b2(CF(CF3)0)b3(CF ₂ CF(CF3)0)b4- wherein:

- b1 , b2, b3, b4, are independently integers ³ 0 such that the number average molecular weight (M _n ) ranges from 400 to 10,000, preferably from 400 to 5,000; preferably b1 is 0, b2, b3, b4 are > 0, with the ratio b4/(b2+b3) being >1 ;

(RF-HC) -(CF2CF20)CI (CF20)C2(CF2(CF2)CWCF ₂ 0)C3- wherein:

- cw is 1 or 2;

- d , c2, and c3 are independently integers ³ 0 such that the number average molecular weight (M _n ) ranges from 400 to 10,000, preferably from 400 to 5,000; preferably d , c2 and c3 are all > 0, with the ratio c3/(d +c2) being generally lower than 0.2;

(RF-I I D) -(CF ₂ CF(CF ₃ )0) _d

wherein:

- d is an integer >0 such that the number average molecular weight (M _n ) ranges from 400 to 10,000, preferably from 400 to 5,000;

(RF-I I E) -(CF2CF2C(Hal)20)ei-(CF2CF2CH20)e2-(CF2CF ₂ CH(Hal)0)e3- wherein:

- Hal, equal or different at each occurrence, is a halogen selected from fluorine and chlorine atoms, preferably a fluorine atom;

- e1 , e2, and e3, equal to or different from each other, are independently integers ³ 0 selected in such a way that the (e1 +e2+e3) number average molecular weight (M _n ) ranges from 400 to 10,000.

[0043] Still more preferably, chain (RF) complies with formula (RF-I I I) here below:

(RF1 -III) - (CF ₂ CF20)al(CF ₂ 0)a2- wherein:

- a1 , and a2 are integers > 0 such that the number average molecular weight (M _n ) ranges from 400 to 4,000, with the ratio a2/a1 generally ranging from 0.2 to 5.

[0044] Polyalkylsiloxane chains (Rs)

[0045] As intended herein, a polyalkylsiloxane chain [herein after otherwise referred to as chain (Rs)] comprises, preferably essentially consists of recurring units

Ra,

i

- 05Ϊ— ftb

[units (Us)] of formula: ^s (Us)

in which Ra _s and Rb _s , equal to or different from one another, are independently selected from hydrogen, straight or branched (halo)alkyl and aryl, with the proviso that at least one of Ra _s and Rb _s is not hydrogen.

[0046] Preferred Ra _s and Rb _s groups are straight or branched alkyl groups comprising from 1 to 4 carbon atoms; more preferably, both Ra _s and Rb _s are methyl, i.e. chain (Rs) is a polydimethylsiloxane chain [chain (Rs-I)], which essentially consists of a sequence of recurring units of formula (Us-i) here below:

(Us-i): -OSi(CH ₃ ) ₂ -.

[0047] Minor amount (e.g. < 1 % wt, based on the weight of chain (Rs-I)) of spurious units, defects or recurring unit impurities may be comprised in chain (Rs-I) without this affecting chemical properties of this chain.

[0048] Chain (Rs) has a number average molecular weight (M _n ) typically ranging from 500 to 10,000, preferably from 500 to 5,000.

[0049] Polyoxyalkylene chains (ROA)

[0050] As intended herein, a polyoxyalkylene chain [herein after otherwise referred to as chain (ROA)] is a straight or branched polymer chain consisting of repeating hydrocarbon units comprising at least one catenary ether bond [units (UOA)] ; non-limiting examples of chain (ROA) are chains comprising, preferably essentially consisting of a sequence of units of formula -OR~ _O A-, wherein each of R~ _O A, equal to or different from each other, is, independently at each occurrence, an hydrocarbon divalent group, possibly comprising additional heteroatom(s), and preferably a divalent alkylene group, which may be linear or branched.

[0051] Preferred chains (ROA) are polyoxyethylene chains comprising, preferably essentially consisting of recurring units of formulae (UOA-I) as below detailed, polyoxypropylene chains comprising, preferably essentially consisting of recurring units of formulae (UoA-ii) - (UOA-IV) here below, a polytetramethylene glycole chain, comprising, preferably essentially consisting of recurring units of formula (UOA-V) here below, or a chain comprising, preferably essentially consisting of, a mixture of any of oxyethylene, oxypropylene, oxytetramethylene units (UOA-I) - (UOA-V):

(UOA-I): -OCH2CH2- (UoA-ϋ): -OCH2CH2CH2- (UoA-iii): -OCH(CH ₃ )CH ₂ - (UoA-iv): -OCH ₂ CH(CH ₃ )- (UOA-V): -OCH2CH2CH2CH2-.

[0052] The expression“essentially consisting of” when used in connection with chain (R _O A) is hereby understood to indicate that said chain (R _O A) may comprise, in addition to the listed recurring units, impurities, defects or spurious groups in a minor amount (e.g. < 5 % moles, wrt to total amount of recurring units), these impurities, defects or spurious groups having generally no peculiar effect on properties of chain (R _O A).

[0053] Preferred chains (R _O A) according to the invention are polyoxypropylene chains.

[0054] Chain (ROA) has a number average molecular weight (M _n ) typically ranging from 500 to 10,000, preferably from 500 to 5,000.

[0055] Polycarbonate chains (Rpc) [0056] As intended herein, a polycarbonate chain [herein after otherwise referred to as chain (Rpc)] consists of repeating units [units (Upc)] of formula:

wherein R°PC represents:

- a straight or branched alkylene chain, optionally comprising one or more cycloalkyl, divalent cycloalkyl group, aryl or arylene group as defined above, and wherein npc is an integer such that the polycarbonate chain has a number average molecular weight (M _n ) typically ranging from 500 to 10,000, preferably from 500 to 5,000.

[0057] Polyester chains (RPE)

[0058] As intended herein, a polyester chain [herein after otherwise referred to as chain (RPE)] comprises recurring units [units (UE)] of formula:

(UE) wherein each of R°PE and R°’PE, equal to or different from one another, represents independently a straight or branched alkylene chain, optionally comprising one or more cycloalkyl, divalent cycloalkyl group, aryl or arylene group as defined above, and wherein PE is an integer such that the chain (RPE) has a number average molecular weight (M _n ) typically ranging from 500 to 10,000, preferably from 500 to 5,000.

According to a preferred embodiment, chain (R) of polymer (P1 ) is a chain (Rs) as defined above, preferably a chain (Rs-I).

[0059] Polybutadiene chains (RPBD)

[0060] As intended herein, a polybutadiene chain [herein after otherwise referred to as chain (RPBD)] is a chain comprising recurring units derived from 1 ,3- butadiene monomer, whereas the said recurring units may be formed by connecting the 1 ,3-butadiene monomers end-to-end, so-called 1 ,4-addition polymerisation, either in cis or trans configuration, yielding, respectively, 1 ,4- cis or l ,A-trans units, or by connecting 1 ,3-butadiene monomers via 1 ,2- addition polymerization, so providing 1 ,2- />7J// units.

[0061] The chain (RPBD) may comprise recurring units derived from olefins and dienes other than 1 ,3-butadiene monomer, being nevertheless understood that chains (RPBD) whereas 1 ,3-butadiene is the predominant monomer (e.g. at least 60 % moles, preferably at least 80 % moles, even more preferably 90 % moles) are preferred. Most preferably, chain (RPBD) essentially consists of a sequence of recurring units derived from 1 ,3-butadiene.

[0062] Groups E1 and EV

[0063] End groups E1 and ET typically comprise at least one carboxylic acid group, phosphonic acid group or sulfonic acid group, said at least one acid group comprising at least one hydroxyl group in its protonated form, so that it is capable to form an anionic group via acid/base reaction with the at least one ionisable amino group at one of the ends of polymer (P2). E1 and ET can be equal to or different from one another. Preferably, E1 and ET are equal to one another.

[0064] The polymer (P1 ) may comprise more than two ends, that is to say that it may be a linear polymer of it may be for instance a star-shaped or other branched structure possessing more than two ends. Nevertheless, preferred embodiments are those whereas polymer (P1 ) is a linear polymer possessing only two ends. Each of these ends may comprise one or more than one ionisable acid group, that is to say that polymer (P1 ) as a whole may comprise at least two ionisable acid groups, including for instance three, four, five, six, seven, eight or even more ionisable acid groups. According to a preferred embodiment of the present invention, the polymer (P1 ) comprises four acid end groups as defined above, and more precisely polymer (P1 ) has two chain ends, each end comprising two ionisable acid groups.

[0065] Preferably, groups E1 and ET comply with formula (E1 -A) here below: (E1 -A) -B1 -EA

wherein:

- B1 represents a chemical bond or a hydrocarbon group, which may be a straight or branched alkylene chain, said alkylene chain preferably comprising from 1 to 20, said hydrocarbon group (or said alkylene chain) optionally bearing one or more halogen atoms, one or more further -EA groups and/or optionally comprising one or more heteroatoms or moieties independently selected from:

- cycloalkylene and arylene groups as defined above, -0-, -S-, -0C(0)0-, - 0C(0)NH-, -0C(0)S-, -SC(0)S-, -NHC(0)NH- and -NHC(S)NH; and

- EA represents a -COOH, a -P(0)(0REA)2 or a -S(0) ₂ 0H group, wherein one of REA is hydrogen and the other one is hydrogen or straight or branched alkyl, preferably Ci-C ₄ alkyl. In a preferred embodiment, EA is a -COOH group.

[0066] POL YMER (P2)

[0067] Polymer (P2) can be represented with formula (P2) here below:

(P2) E2-R-E2’

wherein:

- R is a polymer chain consisting of a plurality of non-ionisable recurring units [units (U)], equal or different from one another, as above described for polymer (P1 ), and

- E2 and E2’, equal to or different from one another, are end groups each comprising at least one ionisable amino group.

[0068] All the features described above for polymer chain R in connection with polymer (P1 ) are equally applicable in connection with polymer (P2).

[0069] Groups E2 and E2’

[0070] End groups E2 and E2’ typically comprise at least one ionisable primary, secondary or tertiary amino group. Groups E2 and E2’ can be equal to or different from one another; preferably, groups E2 and E2’ are equal to one another.“Ionisable primary, secondary or tertiary amino group” means that the amino group is in its free form, so that it is capable to form a cationic group via acid/base reaction with the at least one a ionisable acid group at one of the ends of polymer (P1 ).

[0071] The polymer (P2) may comprise more than two ends, that is to say that it may be a linear polymer of it may be for instance a star-shaped or other branched structure possessing more than two ends. Nevertheless, preferred embodiments are those whereas polymer (P2) is a linear polymer possessing only two ends. Each of these ends may comprise one or more than one ionisable amino group, that is to say that polymer (P2) as a whole may comprise at least two ionisable amino groups, including for instance three, four, five, six, seven, eight or even more ionisable acid groups. According to a preferred embodiment of the present invention, the polymer (P2) comprises two amino end groups as defined above, and more precisely polymer (P2) has two chain ends, each end comprising one ionisable amino group.

[0072] Preferably, groups E2 and E2’ comply with formula (E2-A) here below:

(E2-A) -B2-N(RR ₂ )2

wherein:

- B2 represents a chemical bond or a hydrocarbon group, which may be a straight or branched alkylene chain, said alkylene chain preferably comprising from 1 to 20, said hydrocarbon group (or said alkylene chain) optionally bearing one or more halogen atoms, one or more further -N(RP2)2 groups and/or optionally comprising one or more heteroatoms or moieties independently selected from:

- cycloalkylene and arylene groups as defined above;

-N(RR2 _* ) groups, wherein RP _2* represents hydrogen or straight or branched alkyl, preferably Ci-C ₄ alkyl, more preferably methyl;

- any of -0-, -S-, -0C(0)0-, -0C(0)NH-, -0C(0)S-, -SC(0)S-, -NHC(0)NH and -NHC(S)NH groups; and

- RP2 represents hydrogen or straight or branched alkyl, preferably Ci-C ₄ alkyl. [0073] Polymers (P1) and (P2) wherein chain (R) is a chain (RF) [herein after polymers (PF1) and (PF2)]

[0074] Polymers (PF1 ) and (PF2) can be prepared according to methods known in the art for the synthesis of PFPEs. In particular, the synthesis of polymers (PF1 ) and (PF2) wherein chain (RF) is a chain of formula (RF-I) can be carried out by oxypolymerization of fluoroolefins, followed by conversion of a resulting -CFXC(0)F terminated polymer (“acyl fluorideterminated polymer”, wherein X is as defined above) into the corresponding ethyl ester of formula (EF1 ):

(E _F 1 ) (R _F -l)-(CFXC(0)OEt) ₂ .

[0075] Ester (EF1 ) can be either hydrolyzed to provide an acid polymer (PF1 ) wherein E and E’ represent -CFXC(0)OFI [herein after (PF1 -A)] or reduced to the corresponding PFPE diol [“diol (DF1 )] of formula (RF-I)-(CFXCFI ₂ 0FI) ₂ [herein after“PFPE diol (DF1 -A)”]. The reduction of ester (EF1 ) can be carried out according to methods known in the art, using reducing agents such as NaBFU, or by catalytic hydrogenation, as disclosed, for example, in US 6509509 A (AUSIMONT S.P.A) 7/5/2001 , US 657341 1 (AUSIMONT S.P.A.) 1 1/21/2002, WO 2008/122639 A (SOLVAY SOLEXIS S.P.A.) 10/16/2008.

[0076] Polymer (PF1 -A) can be used as such in the manufacture of compositions (C).

[0077] Diols (DF1 -A) can be reacted with alkylene oxides, typically ethylene oxide and propylene oxide, in the presence of a base, to provide further diols (DF1 - B) - (DF1 -D) of formulae:

(D _F 1 -B) (RF-l)-[CFXCH20(CH2CH ₂ 0)n°DH]2

(D _F 1 -C) (RF-l)-{CFXCH20[CH(CH3)CH ₂ 0]n°DH}2

(D _F 1 -D) (RF-l)-{CFXCH20[CH ₂ CH(CH3)0]n°DH}2

wherein n°D is a positive number, preferably ranging from 1 to 10, more preferably ranging from 1 to 5. Diols (DF1 -B) - (DF1 -D) can also be used as precursors for polymers (PF1 ) and (PF2), as explained below in greater detail.

[0078] Diols (DF1 -A) and (DF1 -B) with a chain (RF-III) and wherein in (DF1 -B) n°D ranges from 1 to 2 are available from Solvay Specialty Polymers Italy S.p.A. with the tradename Fomblin ^® Z DOL. Other diols (DF1 -B) - (DF1 -D) can be obtained following the teaching of WO2014090649 (SOLVAY SPECIALTY POLYMERS ITALY SPA).

[0079] Throughout the present application, ester (EF1 ), diols (DF1 ) and polymers (PF1 ) and (PF2) are visually represented as bifunctional compounds. However, it is known to a person skilled in the art that ester (EF1 ) and diols (DF1 ) such are always obtained as mixtures comprising the corresponding mono-functional and neutral esters or alcohols which form in the oxypolymerization reaction, i.e. compounds terminating with (per)haloalkyl groups at one or both ends, typically C1-C3 perfluoroalkyl groups. Ester (EF1 ) and diols (DF1 ) are thus characterized by an average functionality (F) as defined above; the higher the average functionality, the higher the number of bifunctional species. As a consequence, polymers (PF1 ) and (PF2) obtained from ester (EF1 ) or from diols (DF1 ) are also in admixture with corresponding polymers wherein one end of chain (RF) bears a (per)haloalkyl group and with neutral compounds present in the (EF1 ) or diol (DF1 ) used as starting material. Usually, neutral compounds that comprise (per)haloalkyl groups at both ends are present in an amount lower than 0.04% on a molar basis. For the purpose of the present invention, ester (EF1 ), diols (DF1 ) having an average functionality (F) higher than 1 , preferably of at least 1.5 can be used.

[0080] PFPE ester (EF1 ) and diols (DF1 ) can be used as precursors for the synthesis of polymers (PF1 ) and (PF2) with suitable reaction partners, according to methods known in the art for the manufacture of PFPE derivatives.

[0081] For example, PFPE ester (EF1 ) can be used as precursor for polymers (PF1 ) or (PF2) wherein groups (E1 -A) and (E2-A) respectively comply with formulae (E1 -Aa), (E1 -Ab), (E2-Aa), (E2-Ab) herein below:

(E1 -Aa) -CF ₂ C(0)NH-B1 *-E _A

(E1 -Ab) -CF ₂ C(0)0-B1 *-E _A

(E2-Aa) -CF ₂ C(0)NH-B2 ^* -N(R _P2 ) ₂

(E2-Ab) -CF ₂ C(0)0-B2 ^* -N(R _P2 ) ₂ wherein:

- E _A and Rp ₂ are as defined above and

- B1 ^* and B2 ^* represent straight or branched alkylene chains, said alkylene chain preferably comprising from 1 to 10 carbon atoms and optionally bearing one or more halogen atoms, and/or optionally comprising one or more heteroatoms or moieties independently selected from:

- cycloalkylene and arylene groups as defined above;

-0-, -S-, -0C(0)0-, -0C(0)NH-, -0C(0)S-, -SC(0)S-, -NHC(0)NH and - NHC(S)NH-.

[0082] B1 ^* may also comprise one or more further EA groups, while B2 ^* may also comprise one or more further -N(RP2)2 groups.

[0083] B2 ^* may also comprise one or more -N(RP2 _* )- moieties.

[0084] Polymers (PF1 ) or (PF2) wherein groups (E1 -A) and (E2-A) comply with formulae (E1 -Aa), (E1 -Ab), (E2-Aa), (E2-Ab) as defined above can be manufactured by reacting ester (EF1 ) with compounds of formulae IMH2- B1 ^* - EA and HO-B2*-N(RP2)2, wherein B1 ^* , EA, B2 ^* and N(RP2)2 are as defined above.

[0085] Should B1 ^* and B2 ^* polymers (PF1 ) or (PF2) contain one or more of the aforementioned heteroatoms or moieties, end groups (E1 -Aa), (E1 -Ab), (E2- Aa), (E2-Ab) can also be build up by subsequent reactions of ester (EF1 ) with suitable reaction partners. For example, a polymer (PF1 ) wherein group (E1 - Aa) comprises a -NHC(O) moiety can be obtained by reacting ester (EF1 ) first with a diamine and then with an acid comprising two EA groups. A polymer (PF1 ) wherein group (E1 -Ab) comprises one or more -0-C(0)-NH moieties can be obtained by reacting ester (EF1 ) first with a diol and the with a diisocyanate.

[0086] PFPE diols (DF1 ) can be used, for example, as precursors of polymers (PF1 ) and (PF2) wherein groups (E1 -A) and (E2-A) respectively comply with the formulae listed below:

(E1 -A ^** ) -CFXCH2(OCH ₂ CH ₂ )nD-B1 **-E _A (E2-A ^** ) -CFXCH ₂ (OCH2CH2)nD-B2 ^** -N(Rp ₂ )2

in which X, EA and Rp ₂ are as defined above and nD is 0 or a positive number, preferably from 1 to 10, more preferably from 1 to 5, while B1 ^** and B2 ^** represent a chemical bond or straight or branched alkylene chains, said alkylene chains preferably comprising from 1 to 10 carbon atoms and optionally bearing one or more halogen atoms, and/or comprising one or more heteroatoms or moieties independently selected from:

-cycloalkylene and arylene groups as defined above;

-0-, -S-, -0C(0)0-, -0C(0)NH-, -0C(0)S-, -SC(0)S-, -NHC(0)NH- and - NHC(S)NH-.

[0087] B1 ^** may also comprise one or more further EA groups, while B2 ^** may also comprise one or more further -N(RP2)2 groups.

[0088] B2 ^** may also comprise one or more -N(RP2 _* )- moieties.

[0089] For example, starting from a PFPE diol (DF1 -A) or (DF1 -B), polymers (PF2) can be obtained complying with formula (PF2-A):

(PF2-A) (RF-l)-[CFXCH2(OCH ₂ CH2)nDN(Rp2)2]2

in which RF-I , X, RP2 and nD are as defined above.

[0090] Conveniently, polymers (PF2-A) can be obtained by converting a PFPE diol (DF1 -A) or (DF1 -B) into the corresponding sulfonic ester (like the trifluoromethanesulfonyl, perfluorobutylsulfonyl or p-toluenesulfonyl ester) and then reacting the sulfonic ester with an amine of formula FIN(RP2)2, following the procedure disclosed in US 6984759 B (SOLVAY SOLEXIS SPA).

[0091] Amines (PF2-A) can be used as such in the manufacture of compositions (C) or can be used as precursors of other polymers (PF1 ) or (PF2) by reaction with suitable reaction partners according to methods known in the art. For example, convenient polymers (PF1 ) can be obtained by reaction of an amine(PF2-A) with an aromatic polycarboxylic acid or a derivative thereof able to form amido bonds, for example with trimellitic acid or a derivative thereof, such as trimellitic anhydride. Good results were obtained using a polymer (PF1 ) obtained by reacting an amine (PF2-A) of formula (RF-I II)-(CF2CH2NH2)2 with trimellitic anhydride.

[0092] A further example of polymer which can be obtained from a PFPE diol (DF1 ) is a polymer (PF1 ) complying with formula (PF1 -B):

(PF1 -B) (R _F -l)-[CFXCH2(OCH2CH2)nDOCH ₂ COOH]2

wherein (RF-I), X and nD are as defined above by reaction of diol (DF1 ) with an ester of a 2-halo-acetic acid, for example with 2-chloroethyl acetate. The reaction can be conveniently carried out as disclosed in US 7252740.

[0093] Polymer (PF1 -B) can be used as such in the manufacture of compositions (C) or it can in turn be used as precursor for the manufacture of other polymers (P _F 1 ) and (P _F 2).

[0094] Further convenient polymers (PF1) for the preparation of compositions (C) are those complying with the following formulae (PF1 -C) and (PF1 -D) herein below:

(P _F 1 -C) (RF-l)-[CFXCH2(0CH ₂ CH2)nD0C(0)-RBi-C00H]2

(PF1 -D) (RF-l)-[CFXCH2(0CH ₂ CH2)nDNHC(0)-RBi-C00H]2

wherein RF-I , X and nD are as defined above and RBI is C1-C10 straight or branched alkylene, C ₄ -C ₆ cyloalkylene as defined above or C5-C6 arylene as defined above, optionally comprising one or more -COOFI groups. Preferably, chain (RF-I) is a chain (RF-I II) as defined above, X is F, nD is 0 or ranges from 1 to 5 and RBI is selected from 0-, m-, -cyclohexylene and 0-, m-, p- phenylene. Polymers (PF1 -C) and (PF1 -D) can be obtained from diols (DF1 -A), (DF1 -B) and from (PF2-A) by reaction with a diacid of formula HOOC-RBI- COOH wherein RBI is as defined above or with a reactive derivative thereof, like a halide or an anhydride.

[0095] A convenient example of compound (PF1 -C) complies with formula (P _F 1 -Ca) here below:

with group (RF-I II) and nD possessing the meaning as explained above.

[0096] A convenient example of polymer (PF1 -D) complies with formula (P _F 1 -Da) here below:

(P _F 1 -Da) with group (RF-I II) possessing the meaning as explained above.

[0097] Further convenient examples of polymers (P2) for the preparation of compositions (C) are those complying with the following formulae (PF2-B) and (PF2-C):

(PF2-B) (RF-l)-[CFXCH2(0CH ₂ CH2)nD0C(0)-RBi-N(Rp2)2]2

wherein RF-I , X, nD and N(RP2)2 and RBI are as defined above;

(PF2-C) (RF-l)-[CFXCH2(0CH ₂ CH2)nD0C(0)NH-RB2NHC(0)0RB3-N(Rp2)2 wherein RF-I , X, nD and RP2 are as defined above, RB2 is straight or branched Ci-C ₆ alkylene chain optionally comprising a C ₄ -C ₆ cyloalkylene group as defined above or a C5-C6 arylene group as defined above and RB3 is C2-C10 straight or branched alkylene, optionally interrupted by one or more -N(RP2*)- groups as defined above.

[0098] Polymers (PF2-B) can be obtained by reaction of a diol (DF1 -A) or (DF1 -B) with an amidoacid or with a reactive derivative thereof, such as a halide or anhydride. [0099] Polymers (PF2-C) can be obtained by reaction of a diol (DF1 -A) or (DF1 -B) with a diisocyanate and an aminoalcohol.

[00100] Convenient examples of polymers (PF2-C) comply with the formulae (Pp2-Ca) and (Pp2-Cb) here below:

(Pp2-Ca)

(P _F 2-Cb)

[00101 ] Polymers (P1) and (P2) wherein chain (R) is a chain (Rs) [herein after polymers (Ps 1) and (Ps2)]

[00102] Polymers (Ps1 ) and (Ps2) are available on the market, or can be obtained according to methods known in the art. In particular, polymers (Ps1 ) and (Ps2) wherein Ra _s and Rb _s are both methyl can be obtained by hydrolysis of dimethyl chlorosilane to provide a dihydroxy-terminated poly(dimethylsiloxane) and derivatization of the same according to methods known in the art for the manufacture of amines and acids.

[00103] A convenient example of polymer (Ps2) is a polydimethyl siloxane of formula (Ps2-A) here below:

(P _S 2-A) H2N(CH2)ns*Si(CH3)20[Si(CH3)20]nsSi(CH3)2(CH ₂ )ns*NH2 in which ns is a positive number selected in such a way that the number average molecular weight (M _n ) of the [Si(CH ₃ ) ₂ 0] _ns chain ranges from 500 to 10,000, preferably from 500 to 5,000 and ns ^* is 0 or a positive number equal to or higher than 1 , preferably ranging from 1 to 10. Polymers (Ps2-A) wherein ns ^* is 3 is notably commercially available from Aldrich ^® , with various molecular weight (M _n ) of the [Si(CH3)20] _ns chain.

[00104] Polymer (Ps2-A) can be used as such in the manufacture of compositions (C) or can be used as precursor for the manufacture of other polymers (Ps1 ) and (Ps2). For instance, convenient polymers (Ps1) complying with the following formula (Ps1 -A) here below:

(Ps1 -A) R ^* s-[(CH ₂ )ns NHC(0)- RBI -COOH] ₂

wherein ns ^* is 0 or a positive number equal to or higher than 1 , preferably ranging from 1 to 10, and RBI is a C1-C10 straight or branched alkylene, C ₄ -C ₆ cyloalkylene as defined above or C5-C6 arylene, and preferably is selected from 0-, m~, -cyclohexylene and 0-, m-, -phenylene, as already defined above, and wherein R ^* s is a chain of formula

Si(CH3)20[Si(CH ₃ )20]nsSi(CH ₃ )2- , with ns is a positive number selected in such a way that the number average molecular weight (M _n ) of the [Si(CH ₃ ) ₂ 0] _ns chain ranges from 500 to 10,000, preferably from 500 to 5,000, as defined above,

can be obtained by reaction of polymer (Ps2-A) with an acid of formula HOOC-RBI-COOH, wherein RBI is as defined above, or with a reactive derivative thereof, such as a halide or anhydride.

[00105] A convenient example of polymer (Ps1 -A) is one complying with formula (Ps1 - Aa) here below:

wherein Rs is a chain of formula -Si(CH ₃ ) ₂ 0[Si(CH ₃ ) ₂ 0] _ns Si(CH ₃ ) ₂ - , with ns is a positive number selected in such a way that the number average molecular weight (M _n ) of the [Si(CH ₃ ) ₂ 0] _ns chain ranges from 500 to 10,000, preferably from 500 to 5,000, as defined above.

[00106] A further convenient example of polymer (Ps1) is a polymer complying with formula (Ps1 -B):

(Ps1 -B) Rs-[(CH ₂ ) _ns* 0C(0)- RBI-COOH] ₂ wherein ns ^* and RBI are as defined above and Rs is a chain of formula - Si(CH3)20[Si(CH ₃ )20]nsSi(CH ₃ )2-, with ns is a positive number selected in such a way that the number average molecular weight (M _n ) of the [Si(CH ₃ ) ₂ 0]ns chain ranges from 500 to 10,000, preferably from 500 to 5,000, as defined above.

[00107] Polymer (Ps1 -B) can be obtained by reaction of a dihydroxy-terminated silane precursor of formula:

H0(CH2)ns _* Si(CH ₃ )20[Si(CH ₃ )20]nsSi(CH ₃ )2(CH ₂ )ns _* 0H

by reaction with an acid of formula HOOC-RBI -COOH, wherein RBI is as defined above, or with a reactive derivative thereof, such as a halide or anhydride.

[00108] Polymers (P1) and (P2) wherein chain (R) is a chain (RQA) [herein after polymers (P1QA) and (P2QA)]

[00109] Polymers (P1 OA) and (P2OA) are available on the market or can be obtained according to methods known in the art. Preferred examples of polymers (P1 OA) and (P2OA) are those comprising a polyoxyethylene chain, a polyoxypropylene chain, a polytetramethylene glycole chain, or a chain comprising a mixture of any of oxyethylene, oxypropylene, oxytetramethylene units.

[001 10] For example, starting from a polyoxyalkylene diol of formula (DOA1 ):

(DOA1 ) H-(OR*OA)n _* OA-OH

wherein each of R*OA, equal to or different from each other, is, independently at each occurrence, a straight or branched alkylene divalent group, typically an ethylene, propylene or a tetramethylene group, and P*OA is an integer selected in such a way as the number average molecular way ranges from 500 to 5,000, polymers (POA1 ) and (POA2) can be obtained by methods know in in the art by reaction with suitable reaction partners. A diol (DOA-1 ) wherein R*OA is substantially at each occurrence an ethylene group is commercially available from Aldrich ^® . [001 1 1] The expression“substantially at each occurrence” in connection with moieties R*OA of polymers (P1 OA) or (P2OA) is meant to indicate that minor amounts (i.e. < 1 % in moles) of groups R*OA other than those specified may be present as impurities, defects or spurious components, being understood that these impurities, defects or spurious component may not substantially affecting the properties of chain R*OA.

[001 12] For example, polymers (P1 OA) complying with formula (P1 OA-A):

(P1 OA-A) HOOC-R _B i-(OR* ₀ A)n _* oA-0-R _B i-COOH

wherein R _B I , R*OA and P*OA are as defined above, can be obtained by reaction of a diol (DOA1 ) with a halo-alkyl or haloalkylene acid X°-R _B I-COOH wherein X° is halogen and R _B I is a C1-C10 straight or branched alkylene, C ₄ - Ce cyloalkylene as defined above or C5-C6 arylene, and preferably is selected from 0-, m-, -cyclohexylene and 0-, m-, -phenylene, as already defined above, or with a corresponding halide or ester. For example, a polymer (P1 OA-A) wherein R _B I is -CFI2- can be obtained by reaction of diol (DOA1 ) with a 2-halo acetic acid or halide or ester thereof, such as with 2-chloroacetic acid ethyl ester.

[001 13] A polymer (P1 _O A-A) wherein R* _O A is substantially at each occurrence an ethylene group and R _B I is -CFI2- is available from Aldrich ^® .

[001 14] Polymers (P1 _O A) complying with formula (P1 _O A-B):

(P1 _O A-B) HOOC-R _B I- C(0)-(OR*oA)n _* oA-0-C(0)-R _B i-COOH

can be obtained by reaction of a diol (DOA-1 ) with a diacid of formula FIOC(O)- R _B I -COOFI, wherein R _B I is as defined above, or with a reactive derivative thereof, such as an halide or anhydride.

[001 15] Polymers (P2 _O A) complying with formula (P2 _O A-A):

(P2OA-A) H ₂ NR*oA-(OR*oA)n*oA-N H ₂

wherein R*OA and P*OA are as defined above can be obtained from a diol (D _O A1 ) by conventional reactions for the replacement of the hydroxyl group into an amino group. A polymer (P2 _O A-A) wherein R* _O A is substantially at each occurrence a propylene group of formula -CH2-CH2- is available on the market from Aldrich ^® .

[001 16] According to an embodiment of the invention, at least one of the following conditions (preferably both conditions) are satisfied:

(1 ) polymer (P1 ) complies with formula (P1 _O A-A);

(2) polymer (P2) complies with formula (P2 _O A-A)

wherein:

(P2OA-A) H ₂ NR*oA-(OR*oA)n*oA-NH ₂

(P1 OA-A) HOOC-R _Bi -(OR*o _A )n _* o _A -0-R _Bi -COOH

in which:

- each of R* _O A, equal to or different from each other, is, independently at each occurrence, a straight or branched alkylene divalent group, typically an ethylene, propylene or a tetramethylene alkylene group,

-n ^* oA is an integer selected in such a way as the number average molecular weight ranges from 500 to 5,000, and

- R _B I is C1-C10 straight or branched alkylene, C ₄ -C6 cyloalkylene or C5-C6 arylene, optionally comprising one or more -COOH groups.

[001 17] Preferably, the polymer (P1 ) and (P2) in composition (C) have respectively the formulae (P1 OA-A) and (P2OA-A) as defined above, R*OA is substantially at each occurrence a propylene group of any of formulae - CH2CH2CH2-, -CH2- CH(CH3)- and -CH(CH3)-CH2-, and R _B I comprises one -COOH group.

[001 18] Polymers (P1) and (P2) wherein chain (R) is a chain (Rpc) [herein after polymers (Pipe) and (P2 PC)]

[001 19] Polymers (Pi pe) and (P2PC) can be manufactured by reaction of a diol of formula (D°PC1 ):

(D°P _C 1 ) HO-(R°pc)-OH wherein (R°pc) is a straight or branched alkylene chain, preferably a C ₂ - C ₁₀ alkylene chain, optionally comprising ethereal oxygen atoms; and a carbonate, typically diphenylcarbonate, to provide a dihydroxy- terminated polycarbonate of formula (DPC1 ):

(DRC1 ) H-[0-R°pc-0C(0)] _nP c0-R ^o pc-0H

wherein R°pc and npc are as defined above; followed by subsequent reaction with suitable reactive compounds according to methods known in the art to provide polymers (P1 pc) and (P2 PC).

[00120] Dihydroxy-terminated polycarbonates (DPC1 ) having an average number molecular weight (M _n ) ranging from 500 to 3,000 are notably commercially available, for example, from UBE as Ethernacoll ^® PH.

[00121] For example, convenient polymers (Pi pe) can be obtained by reaction of (DPC1 ) with a halo-alkyl or haloalkylene acid ester, preferably with an acid of formula X°-RBI-COOH wherein X° is halogen and RBI is as defined above, or an ester thereof, for example with 2-chloro acetic acid ethyl ester.

[00122] Further convenient polymers (Pi pe) [polymers (P1 PC-B)] can be manufactured by reaction of diol (DPC1 ) with an acid of formula HOOC-RBI -COOH wherein RBI is as defined above, or with a reactive derivative thereof, such as a halide or an anhydride.

[00123] Convenient polymers (P2PC) complying with formula (P2PC-A):

(P2PC-A) (RP2)2N-R ^O PC-0[C(0)0-R°PC0] _np c-i R ⁰ pc-N(Rp ₂ )2

wherein RP ₂ , R°PC and npc are as defined above can be manufactured from diol (D°PC1 ) by converting the terminal hydroxyl groups into amino groups according to methods known in the art.

[00124] Polymers (P2PC-A) wherein at least one of Rp ₂ is hydrogen can be used as precursors of further polymers (Pi pe) and (P2PC). For example, polymers of formula (P1 pc-C):

(P1 pc-C) HOOC-RBI (0)C-R _P2 N-R °P _C -0[C(0)0-R°P _C 0] _nP c-iR°pc-NRp ₂ C(0) RBI -COOH

can be obtained by reaction with a diacid of formula HOOC- RBI-COOH wherein RBI is as defined above or with a reactive derivative thereof, such as a halide or anhydride. [00125] Polymers (P1) and (P2) wherein chain (R) is a chain (RPE) [herein after polymers (P1PE) and (P2PE)”

[00126] Polymers (P1 PE) and (P2PE) can be prepared according to methods known in the art starting from a polyester diol [diol (DPE1 )]. Diols (DPE1 ) can be obtained by polycondensation of dicarboxylic acids or lactams and diols. Polyester diols are commercially available; for example, polycaprolactone diols are available from Perstop under the tradename Capa™. Convenient polymers (P1 PE) can be obtained by reaction of a diol (DPE1 ) with a halo-alkyl or haloalkylene acid ester, preferably with an acid of formula X°-RBI-COOH wherein X° is halogen and RBI is as defined above, or an ester thereof, for example with 2-chloro acetic acid ethyl ester. Further convenient polymers (PPE1 ) can be obtained by reaction of a diol (DPE1 ) with an acid of formula HOOC- RBI-COOH wherein RBI is as defined above, or with a reactive derivative thereof, such as a halide or anhydride.

[00127] Polymers (PPE2) with -N(RP2)2 end groups can be obtained from diols (DPE1 ) according to methods known in the art for the replacement of the hydroxyl group with an amino group. Polymers (PPE2) thereby obtained can be in turn used as precursors for other polymers (PPE1 ) or (PPE2) by reaction with suitable precursors according to methods known in the art.

[00128] Polymers (P1) and (P2) wherein chain (R) is a poiybutadiene chain (RPBD) [herein after“polymers (PPBD 1) and (PPBD2)”]

[00129] Polymers (PPBD1 ) and (PPBD2) can be obtained from dihydroxy terminated polybutadienes according to methods disclosed in the art.

[00130] Such polybutadienes are available, for example, from Cray Valley; one of them is marketed as Poly bd ^® R-45HTLO.

[00131] Convenient polymers (PPBD1 ) can be obtained by reaction of a dihydroxy terminated poiybutadiene [diol (DPBD1 )] with a halo-alkyl or haloalkylene acid ester, preferably with an acid of formula X°-RBI-COOH wherein X° is halogen and RBI is as defined above, or an ester thereof, for example with 2-chloro acetic acid ethyl ester. Further convenient polymers (PPBD1 ) can be obtained by reaction of a dihydroxy terminated polybutadiene with an acid of formula HOOC-RBI-COOH

wherein RBI is as defined above, or a reactive derivative thereof.

[00132] Polymers (PPBD2) with -N(RP2)2 end groups can be obtained from a dihydroxy terminated polybutadiene (DPBD1 ) according to methods known in the art for the replacement of the hydroxyl groups with an amino group. Polymers (PPBD2) thereby obtained can be in turn used as precursors for other polymers (PPBD1 ) or (PPBD2) by reaction with suitable precursors according to methods known in the art.

[00133] The anthracene compound

[00134] The composition (C) may comprise one or more than one compound (A).

[00135] The anthracene compound or compound (A) generally complies with formula (ANTH-1 ) below:

(ANTH-1 )

where:

- each if R _an th, equal to or different from each other at each occurrence is a halogen, a C1-C20 (hydro)carbon group, possibly comprising one or more than one heteroatom;

- j is zero or is an integer of 1 to 4;

- k is zero ir is an integer of 1 to 3;

- Ea _nth is a chemical bond or is a hydrocarbon group, which may be a straight or branched alkylene chain, said alkylene chain preferably comprising from 1 to 20, said hydrocarbon group (or said alkylene chain) optionally bearing one or more halogen atoms, one or more further -l _an th groups and/or optionally comprising one or more heteroatoms or moieties independently selected from:

- cycloalkylene and arylene groups as defined above, -0-, -S-, -0C(0)0-, - 0C(0)NH-, -0C(0)S- -SC(0)S-, -NHC(0)NH- and -NHC(S)NH; and

- lanth represents:

(i) an acid group selected from -COOH, -P(0)(0R _Ea nt _h ) ₂ and -S(0) ₂ 0H, wherein one of R _Eanth is hydrogen and the other one is hydrogen or straight or branched alkyl, preferably Ci-C ₄ alkyl. In a preferred embodiment, lant _h is a - COOH group; or

(ii) an amine group selected from -N(R _anth 2)2 wherein R _anth 2 represents hydrogen or straight or branched alkyl, preferably Ci-C ₄ alkyl, more preferably methyl.

[00136] According to certain embodiments, compound (A) comprises only one ionisable group selected from ionisable acid groups and ionisable amine groups. According to other embodiments, which are particularly advantageous when the composition (C) is required to possess a higher viscosity, the compound(A) comprises more than one ionisable groups, as above detailed. In particular, compound (A) may advantageously comprise two ionisable groups, three ionisable groups, four ionisable groups or even more than four ionisable groups.

[00137] Preferred compounds (A) which may be used in formulating composition (C) according to the invention are notably:

- 1 -anthracene carboxylic acid;

- 1 ,8 anthracene dicarboxylic acid;

- 1 -amino-anthracene;

- 1 ,8-diamino-anthracene.

[00138] The composition (C) generally comprise a major amount of polymers (P1 ) and (P2) and a minor amount of compound (A), as above detailed, that is to say, it may be qualified as a polymer composition. [00139] The amount of compound (A) is generally of at least 0.01 , preferably at least 0.05 % wt, and/or at most 10 % wt, preferably at most 7 % wt, more preferably at most 5 % wt, with respect to the combined weight of polymer (P1 ), polymer (P2) and compound (A).

[00140] The equivalent ratio between ionisable groups of polymer (P1), polymer (P2) and compound (A) is advantageously such to maximize ionic bonding between acid groups of polymer (P1 ) and of compound (A), if any, and amine groups of polymer (P2) and of compound (A), if any. The composition (C) will hence comprise an overall amount of acid groups of polymer (P1) ) and of compound (A), if any, and an overall amount of amine groups of polymer (P2) and ) and of compound (A), if any which is substantially similar. In other terms, the ratio between the equivalents of ionisable acid groups and the equivalents of ionisable amine groups in said composition (C) will tend to be close to unitary, and will preferably range from 1.1 to 0.9. Most preferably the equivalent ratio is about 1.

[00141] For the avoidance of doubt, the ratio between the equivalents of ionisable groups is referred to the acid/base reaction between the at least one ionisable acid group of polymer (P1 ) and possibly of compound (A) and the at least one ionisable amino group of polymer (P2) and possibly compound (A).

[00142] By the term“at least one polymer (P1 )” is meant in the present invention that only one or more than one polymers (P1 ) may be used in the preparation of the present composition (C).“More polymers” means that polymers (P1 ) can be used differing from one another in the nature of units (U) of the chain (R), in the nature of end groups (E1) and (ET), in the molecular weight, or in a plurality of the said features.

[00143] By the term“at least one polymer (P2)” is meant in the present invention that only one or more than one polymers (P2) may be used in the preparation of the present composition (C).“More polymers” means that polymers (P2) can be used differing from one another in the nature of chain (R), in the nature of end groups (E2) and (E2’), in the molecular weight, or in a plurality of the said features.

[00144] Similarly, by the term“at least one compound (A)” is meant in the present invention that only one or more than one compounds (A) may be used in the preparation of the inventive composition (A). When more than one compounds (A) are used, the compounds (A) so used by differ because of the number or nature of the ionisable groups comprised therein, and/or they may differ because of any other structural feature, e.g. the positioning of the ionisable substituent groups on the anthracene polycondensed rings and/or the presence and/or positioning of optional additional non-ionisable substituents.

[00145] According to a preferred embodiment of the present invention one polymer (P1 ) and one polymer (P2) are used in the manufacture of the composition (C); chain (R) of polymer (P1 ) can be the same or different from chain (R) of polymer (P2). Notably, chain (R) of polymer (P1 ) may comprise recurring units of same nature as chain (R) of polymer (P2) and may possess same, similar or different molecular weight.

[00146] According to a preferred embodiment, chain (R) of both polymer (P1 ) and polymer (P2) is a polyalkylsiloxane chain or a chain (Rs) as defined above in more detail.

[00147] Most preferably, embodiments which were found to provide particularly good results were those wherein:

- Polymer (P2) was a polymer of formula (Ps2-A), as above detailed, i.e. a polymer of formula:

H2N(CH2)ns Si(CH3)20[Si(CH3)20]nsSi(CH ₃ )2(CH2)ns NH2 in which ns is a positive number selected in such a way that the number average molecular weight (M _n ) of the [Si(CH3)20] _ns chain ranges from 500 to 10,000, preferably from 500 to 5,000 and ns ^* is 0 or a positive number equal to or higher than 1 , preferably ranging from 1 to 10; and - Polymer (P1 ) was a polymer of formula (Ps1 -A), as above detailed, i.e. a polymer of formula: R ^* s-[(CH ₂ ) _ns* NHC(0)- RBI-COOH]2 _, wherein ns ^* is 0 or a positive number equal to or higher than 1 , preferably ranging from 1 to 10, and RBI is a C1-C10 straight or branched alkylene, C ₄ -C6 cyloalkylene as defined above or C5-C6 arylene, and preferably is selected from 0-, m-, -cyclohexylene and 0-, m-, -phenylene, as already defined above, and wherein R ^* s is a chain of formula Si(CH3)20[Si(CH ₃ )20]nsSi(CH ₃ )2- , with ns is a positive number selected in such a way that the number average molecular weight (M _n ) of the [Si(CH ₃ ) ₂ 0] _ns chain ranges from 500 to 10,000, preferably from 500 to 5,000;

- Compound (A) was selected from the group consisting of 1 -anthracene carboxylic acid; 1 ,8 anthracene dicarboxylic acid; and 1 -amino- anthracene; 1 ,8-diamino-anthracene.

[00148] Composition (C) can be shaped in three-dimensional articles according to well-known technologies, including all forms of molding, casting, coating, and the like.

[00149] It may be beneficial for composition (C) to comprise a liquid medium [medium (L)]. When composition (C) comprises a liquid medium, polymer (P1 ), polymer (P2) and compound (A) may be, independently from each other, at least partially solubilized in the said medium (L). Otherwise, said polymer (P1), polymer (P2) and compound (A) may be dispersed in the said medium (L). Generally, an organic solvent having ability to at least partially solubilize polymer (P1 ), polymer (P2) and compound (A) may be used. If necessary, this liquid medium (L) may be removed after having achieved, through its presence, an intimate mixing in solubilized state of the above mentioned polymer (P1 ), polymer (P2) and compound (A).

[00150] The medium (L) typically comprises one or more organic solvents selected from the group consisting of: - aliphatic, cycloaliphatic or aromatic ether oxides, more particularly, diethyl oxide, dipropyl oxide, diisopropyl oxide, dibutyl oxide, methyltertiobutylether, dipentyl oxide, diisopentyl oxide, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether benzyl oxide; dioxane, tetrahydrofuran (THF),

- glycol ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monophenyl ether, ethylene glycol monobenzyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol mono-n-butyl ether,

- glycol ether esters such as ethylene glycol methyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate,

- alcohols such as methyl alcohol, ethyl alcohol, diacetone alcohol,

- ketones such as acetone, methylethylketone, methylisobutyl ketone, diisobutylketone, cyclohexanone, isophorone,

- linear or cyclic esters such as methyl acetoacetate, dimethyl phthalate, y- butyrolactone,

- linear or cyclic carboxamides such as N,N-dimethylacetamide (DMAC), N,N- diethylacetamide, dimethylformamide (DMF), diethylformamide or N-methyl-2- pyrrolidone (NMP),

- organic carbonates for example dimethyl carbonate, diethyl carbonate, dipropyl carbonate, dibutyl carbonate, ethylmethyl carbonate, ethylene carbonate, propylene carbonate, vinylene carbonate;

- organosulfur solvents, such as dimethyl sulfoxide (DMSO) and sulfolane (tetramethylene sulfone);

- diesters of formula (Ide), esteramides of formula (l _ea ) and diamides of formula (Ida):

R ¹ 0(0)C-Z _de -C(0)0R ² (Ide)

R ³ 0(0)C-Z _ea -C(0)NR4R5 (lea) R ⁵ R ⁴ N (O)C-Z _da -C(O) N R ⁴ R ⁵ (I _da ) wherein:

- R ¹ and R ² , equal to or different from each other, are independently selected from the group consisting of C1-C3 hydrocarbon groups,

- R ³ is selected from the group consisting of C1-C20 hydrocarbon groups, and

- R ⁴ and R ⁵ , equal to or different from each other, are independently selected from the group consisting of hydrogen and C1-C36 hydrocarbon groups, optionally substituted, being understood that R ⁴ and R ⁵ might be part of a cyclic moiety including the nitrogen atom to which they are bound, said cyclic moiety being optionally substituted and/or optionally comprising one or more heteroatoms, and mixtures thereof, and

- Z _de , Z _ea and Z _da , equal to or different from each other, are independently linear or branched C2-C10 divalent alkylene groups.

[00151] The present invention also relates to a supramolecular adduct obtained by exposing to UV light at a wavelength ranging from 300 nm to 600 nm, preferably from 350 nm to 400 nm the composition (C), as above detailed.

[00152] The way of conveying UV radiation to the composition (C) is not specifically restrained, and UV radiation sources of different type may be used. Further, a source emitting a monochromatic radiation or a source emitting a wider range of wavelength may be used.

[00153] The supramolecular adduct is generally obtained by exposing to said radiation the composition (C), after this latter has been shaped in its three- dimensional form which is advantageously suitable for its intended use.

[00154] The present invention further relates to a method for coating a surface, comprising:

a) applying to the surface the composition (C), as detailed above,

wherein composition (C) optionally comprises a liquid medium [medium (L)], as above detailed, and/or optionally comprises one or more than one additive, and b) irradiating the surface at a wavelength ranging from 300 nm to 600 nm, preferably from 350 nm to 400 nm.

[00155] The nature of the surface is not particularly limited; metal surfaces, plastic surfaces, composite surfaces, ceramic surfaces may be equally coated.

[00156] The metal surface which can be used in this invention may be any of those metal materials which are generally used in various apparatuses, appliances and instruments which may be exposed to corrosive/harsh environment. Non limiting examples of metal surfaces which can be coated with composition (C) are surfaces of shaped metal parts used for instance in architecture (including e.g. frame rails, joists, girders, etc.), industrial plants (e.g. pipes, flanges, valves...), in the automotive industry. Suitable metal surfaces are included for example in structural materials, electrically conductive materials, valve metals with corrosion resistance.

[00157] Examples of metal constituents of the metal surface are titanium, tantalum, zirconium and niobium, alloys composed mainly, e.g., containing more than about 50% by weight, of these metals, e.g. Ti-Ta alloys, Ti-Ta-Nb alloys, Ti- Ta-Zr alloys, Ti-Pd alloys, etc., and lower-cost metal materials with good workability, such as iron, nickel, cobalt, copper or alloys composed mainly, e.g., containing more than about 50% by weight, of these metals, e.g., carbon steel, stainless steel, Ni-Cu alloys, brass, etc.

[00158] Low-melting metals such as aluminum, magnesium and lead can also be used.

[00159] Metal surface may be solely constituted by an individual metallic material (be it a metal in its zero oxidation state, or an alloy of metals in their zero oxidation state, or a composition including one or more than one metals in their zero oxidation state) or may comprise a superficial anti-corrosion coating, such as e.g. anodized layers or other metal coating layers.

[00160] Anodized layers are created on the metal substrate through an electrochemical process that converts the surface of the metal substrate into durable, corrosion-resistant, anodic oxide finish. Aluminum is ideally suited to anodizing, although other nonferrous metals, such as magnesium and titanium, also can be anodized. So, metal surfaces of Aluminum, Magnesium, Titanium may comprise anodized surfaces.

[00161] Otherwise, suitable metals which can be coated on the metal surface are any of those metals which have inherent corrosion resistance and can be alloyed with the metal substrate. Suitable coating metals include tantalum, zirconium, niobium, titanium, molybdenum, tungsten, vanadium, chromium, nickel, silicon, and alloys composed mainly of these metals.

[00162] Generally, the metal surface is an iron surface, such as a cast iron surface (e.g. grey cast iron, white cast iron, malleable iron, ductile or nodular iron, Ni- hard type iron, Ni-resist type iron), or a steel surface, such as a stainless steel or carbon steel surface.

[00163] The surface may have any shape; e.g. it may be under the form of a wire, a sheet or film or may have a different three-dimensional shape, e.g. it may have a tubular shape, or whichever other geometry, including irregular shapes.

[00164] Methods for applying composition (C) on the said surface are not particularly limited; among coating technique, spray coating, knife coating, slot die coating, roll coating, brushing and/or any other suitable technique may be used.

[00165] Depending on the technique used, composition (C) may comprise a liquid medium [medium (L)], as above detailed, so as to advantageously match the liquid viscosity requirements for being processed by the selected coating technique.

[00166] In cases wherein composition (C) comprises a medium (L), and more specifically one or more than one of the organic solvents listed above, the method for coating typically comprises a step c) of at least partially evaporating the said medium (L). Step c) may occurs prior to step b), simultaneously as per step b) or after step b). [00167] The step b) of irradiating is advantageously carried out using a UV radiation source possessing the features as above detailed in connection with the supramolecular adduct.

[00168] The present invention also relates to a method for manufacturing a formed article, comprising:

a) filling a mould with a composition (C), as above detailed,

wherein composition (C) optionally comprises a liquid medium [medium (L)], as above detailed, and/or optionally comprises one or more than one additive, so as to obtain a filled mould, and

b) irradiating the filled mould at a wavelength ranging from 300 nm to 600 nm, preferably from 350 nm to 400 nm.

[00169] While a medium (L) may be used for the preparation of the composition (C), it is generally understood that a step of at least partial removal of medium (L) from the composition (C) would be recommended before step a) of filling a mould.

[00170] The method of manufacturing a formed article may further additionally comprise a step of applying pressure to the filled mould and/or may comprise a step of heating the filled mould.

[00171] It is also understood that the method will comprise a step of removing the formed article from the mould, after irradiation has taken place.

[00172] Finally, the present invention relates to a method for recycling a coating or a formed article, comprising the supramolecular adduct obtained by exposing to UV light at a wavelength ranging from 300 nm to 600 nm, wherein the method comprises submitting the coating or formed article to UV irradiation at a wavelengths lower than 300 nm.

[00173] The present invention also relates to a recycled material obtainable by the recycling methods of the present invention.

[00174] 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.

[00175] The invention will be now be described in connection with the following examples whose purpose is to illustrate the invention, but not limiting the same.

[00176] EXAMPLES

[00177] Materials

[00178] Poly(dimethylsiloxane), bis(3-aminopropyl) terminated (Mn 3000) [herein after (PDMS-A2)] was purchased from Aldrich® and was used as received.

[00179] Solvents and Trimellitic anhydride from Aldrich were used as received.

[00180] Anthracene 1 -carboxylic, and Anthracene 1 -amino from TCI were used as received; Anthracene 1 -8-dicarboxylic methyl ester from TCI was converted in to the corresponding diacid as described in a specific example (Example 2).

[00181] Methods

[00182] Titration

Analytical procedure for the titration of acid polymers (P1) (direct acid/base titration)

A sample specimen of about 1 - 3 g exactly weighed, was dissolved in Solvent: bistrifluoromethylbenzene (HFX)/isopropanol (IPA) 50 /10 ml Titration was performed using as titrating agent: tetramethylammonium hydroxide TMAI 0.1 M in CH3OH, using as electrode: a DG1 15SC electrode from Mettler Toledo.

Analytical procedure for basic polymers (P2) (direct acid/base titration)

A sample specimen of about 1 - 3 g exactly weighed, was dissolved in Solvent: HFX/IPA 50 /10 ml. Titration was performed using as titrating agent HCI 0.1 M in IPA, using as electrode: a DG1 15SC electrode from Mettler Toledo.

[00183] Viscosity [00184] Rheological measurements were carried out with a “Dynamic mechanical spectrometer Rheometric ARES” Instrument Geometry: Cone & Plate (25 mm) Mode: Steady rate sweep test; Shear rate: from 1x1 O ² to 1x10 ³ (1/s); Temperature: 25°C.

[00185] 19F and 1 H NMR

[00186] Spectrometry

[00187] Fluorescence Spectroscopy experiments have been carried out with a FS5 Edinburgh spectrometer. Fluorescence quartz cuvettes with 1 cm path-length have been used. For each formulation analyzed we performed as a first step an Excitation-Emission Map in order to get a fingerprint of the mixture obtained and to locate the best experimental set up for emission measurements (i.e. determining A _exc and A _em ).

As source, a 150 W ozone generating xenon lamp was used, the emission detector was a photomultiplier R928P , cooled and stabilized (range: 200nm - 870nm). The reference Detector used was a UV enhanced silicon photodiode.

For performing measurements of the kinetic of the emission, once located · Aexc and A _em with emission maps, emission intensity was measured as a function of time, recording spectra, with a typical step parameter for scan of 5 nm.

The reverse reaction experiment was carried out measuring single spectra and measuring Fluorescence Emission intensities as a function of time; while during the“wait/delay” time the instrument excitation wavelength were kept at 250 nm.

[00188] Preparation of acid and amino ionisable polymers and anthracene derivatives

[00189] Preparative Example 1 - Synthesis of Acid polydimethylsiloxane (PDMS- COOH) from PDMS-R _h -NFfc containing 1.19 eq/kg of acid groups

A glass reactor was charged with Poly(dimethylsiloxane), bis(3-aminopropyl) terminated Mn 3000 (20.0 g, 13.3 meq) (PDMS-A2) and it was warmed up to 70°C, under mechanical stirring, and dried under vacuum for 2 hours. Trimellitic anhydride was melt at 40°C and it was added (2.6 g 13.5 meq) in the glass reactor. The reaction mass was warmed up to 130°C and kept at this value for two hours. The completion of the reaction was monitored by ¹ H- NMR. The acid content, measured by titration (see method A), was 1 .19 eq/kg, all analyses are consistent with the target structure:

[00190] Preparative Example 2: Synthesis of 1 ,8 anthracene dicarboxylic acid preparation

A glass reactor with a dropping funnel, and protected from the light by an aluminium sheet, was charged with dimethyl anthracene-1 , 8-dicarboxylate (1 .0 g, 3.4 mmoles, 6.8 meq) 12 ml of toluene were added a clear solution is obtained. The temperature is increased at 90°C, and 0.4 g of NaOH (10 mmoles) dissolved in 13ml of water were added dropwise in 10 min, 12 ml of DMSO are added to improve compatibility between the organic and water phase. The reaction will maintained under stirring at 90°C overnight, then IR analysis confirms the complete hydrolysis of the anthracene ester groups. The reaction mass is cooled at room temperature and 10 ml of cone. HCI (37%) is added in 10 min under vigorous stirring. The precipitation of a solid deep yellow is observed, the product is filtered over a 5 micron PTFE filter, and dried at 60°C under vacuum. The analysis (IR and ¹ H-NMR) confirms that target 1 ,8 anthracene dicarboxylic acid is obtained with a total yield > 95%.

[00191 ] General procedure for the manufacture of inventive formulations

[00192] All formulations have been prepared by mixing at 50°C in a reactor equipped with a mechanical stirrer, the three components (amine and acid functionalized macromers and anthracene derivative) in a equivalent ratio = 1 (i.e. nr acidic groups = nr basic groups), in presence of toluene or hexane as solvent, details on composition are reported in each specific example.

[00193] Example 3 - Manufacture of Formulation 1

The following ingredients were used:

PDMS tetra-acid from Prep. Ex. 1 ; 3.44 g (4 meq)

PDMS-diamine (PDMS-A2) 7.3 g (4.88 meq)

Anthracene 1 -carboxylic (Mn 222) 0.2 g (0.88 meq)

Toluene 30 g

The ratio in equivalents (amine:acid from polymenacid from anthracene) was equal to 1.00:0.82:0.18, so corresponding to an overall amine:acid equivalent ratio of 1 .00:1.00.

An aliquot of the formulation was dried and its viscosity measured: 30000 Pas at 25°C.

[00194] Example 4 - Manufacture of Formulation 2

The following ingredients were used:

PDMS tetra-acid from Pr. Ex. 1 : 3.44 (4.00 meq)

PDMS-diamine (PDMS-A2) 7.3 g (4.88 meq)

Anthracene 1 -8-dicarboxylic (Mn 266) 0.12 g (0.88 meq)

Toluene 30 g

The ratio in equivalents (amine:acid from polymenacid from anthracene) was equal to 1.00:0.82:0.18, so corresponding to an overall amine:acid equivalent ratio of 1 .00:1.00.

An aliquot of the formulation was dried and its viscosity measured: 50000 Pas at 25°C

[00195] Example 5 - Manufacture of Formulation 3

The following ingredients were used:

PDMS tetra-acid from Pr. Ex. 1 : 2.91 (3.38 meq)

PDMS-diamine (PDMS-A2) 7.3 g (4.88 meq)

Anthracene 1 -carboxylic (Mn 266) 0.33g (1 .50 meq)

Toluene 30 g The ratio in equivalents (amine:acid from polymenacid from anthracene) was equal to 1.00:0.69:0.31 , so corresponding to an overall amine:acid equivalent ratio of 1.00:1.00.

An aliquot of the formulation was dried and its viscosity measured: 20000 Pas at 25°C.

[00196] Example 6 - Manufacture of Formulation 4

The following ingredients were used:

PDMS tetra-acid from Pr. Ex. 1 : 2.91 (3.38 meq)

PDMS-diamine (PDMS-A2) 7.3 g (4.88 meq)

Anthracene 1 -8-dicarboxylic (Mn 266) 0.20 g (1.50 meq)

Toluene 30 g.

The ratio in equivalents (amine:acid from polymenacid from anthracene) was equal to 1.00:0.69:0.31 , so corresponding to an overall amine:acid equivalent ratio of 1 .00:1.00.

An aliquot of the formulation was dried and its viscosity measured: 20000 Pas at 25°C.

[00197] Example 7 - Manufacture of Formulation 5

The following ingredients were used:

PDMS tetra-acid from Pr.Ex. 1 : 4.3g (5.0 meq)

PDMS-diamine (PDMS-A2) 6.0 g (4.0 meq)

Anthracene 1 -amino (Mn 193) 0.19 g (1.0 meq)

Toluene 30 g

The ratio in equivalents (amine from polymenacid from polymenamine from anthracene) was equal to 1.00:1.25:0.25, so corresponding to an overall amine:acid equivalent ratio of 1.00:1.00.

An aliquot of the formulation was dried and its viscosity measured: 25000 Pas at 25°.

[00198] Example 8- Manufacture of Formulation 6

The following ingredients were used:

PDMS tetra-acid from Pr. Ex. 1 : 1.68 g (1.97 meq) PDMS-diamine (P2) 2.7 g (1 ,8 meq)

Anthracene 1 -amino (Mn 193) 0.028 g (0.17 meq)

hexane 60 g

The ratio in equivalents (amine from polymenacid from polymenamine from anthracene) was equal to 1.00:1.09:0.09, so corresponding to an overall amine:acid equivalent ratio of 1.00:1.00.

An aliquot of the formulation was dried and its viscosity measured: 30000 Pas at 25°.

[00199] Example 9 - UV treatment of formulation 1-5 with high pressure UV mercury lamp (Helios 150 W) creation of supramolecular adducts

All formulations were exposed to a Helios UV high pressure mercury lamp (150W) for 6 hours, with a UV filter for cutting off all radiations below 300 nm. After exposure, the sample was dried from solvent and the viscosity measured and compared to that of the corresponding untreated sample. In all cases a viscosity increase of 50-80% was observed, with respect the formulation before irradiation, confirming the dimerization of anthracene moieties and the formation of a supramolecular crosslinked structure. Conversion of anthracene moieties into dimerized groups was also confirmed and conversion estimated by ¹ H-NMR as ranging from 84% to 98%.

[00200] Example 10 - UV treatment of supramolecular adducts obtained accordingly to example 9 low pressure UV mercury lamp Helios HGL (power density 0.3- 0.5 W/cm ) - depolymerization

All formulations exposed to the high pressure UV mercury lamp as described in example 9, were afterwards subsequently exposed to a Helios UV low pressure mercury lamp for 96 hours emitting radiation at a wavelength of 254 nm, in order to effect depolymerization. The reversible de-crosslinking was confirmed by ¹ H-NMR analysis by measuring the decrease of the diagnostic 1H signal of the internal not aromatic ring and the appearance of diagnostic peaks of anthracene moieties. Moreover, after exposure, specimens were dried and the viscosity measured and compared to that of the corresponding untreated and supramolecular adduct sample. In all cases a viscosity was found to be lower than that before the depolymerization trial, i.e. to that of the supramolecular adduct, and was found to match the original viscosity of formulations, as originally prepared. This confirms that the dimerization of anthracene moiety and the formation of a highly crosslinked supramolecular network is a reversible reaction, that can be activated in one sense or the other by specific UV irradiation.

[00201] Example 11- Measurement of polymerization and de-polymerization directly by UV-spectroscopy on formulation F6

These experiments have been carried out by using a FS5 Edinburgh spectrometer. Procedure has been described in the Methods chapter as applied to a specimen of formulation 6.

[00202] Polymerization - step 1

A multi-dimensional map showing excitation intensity and emission intensities as a function of the wavelength was obtained and is depicted in Figure 1. This map enabled allowed to locate an excitation peak and an emission peak at the following wavelengths:

Aexc : 400 nm , Aem : 450 nm

Next, intensity (expressed in counts) of the emission at A _em : 450 nm (i.e. at maximum emission wavelength) was recorded as a function of time, expressed in seconds; such trend is depicted in Figure 2.

The experimental emission kinetics has been lasted until the absolute value of Fluorescence Emission measured reached about 20% of its initial value, resulting in the duration of the experiment of approximately 6 hours. This means that in 6 hours, under these conditions, conversion of anthracene groups to corresponding adducts/dimerized moieties is 80%.

Experimental data were fitted using as kinetic model a second order chemical reaction, demonstrating an extremely good fit (r> 0.99), so confirming second order kinetic. Graph of this fitting is provided in Figure 3, whereas c is the concentration of the anthracene compound, as measured as a function of time.

The decreasing of the Fluorescence emission intensity is the experimental evidence that the 400 nm excitation is able to generate a dimeric system, giving as a result a quenching of the Fluorescence observed for the monomer state (pursuant to the indications provided in H.B. Laurent et al. Pure & Appl. Chem. , Vol 52, pp.2633-2648, 1980). The sample has then been kept in closed fluorimeter cuvettes in the dark.

[00203] Depolymerization - step 2

The same specimen was used for investigating using fluorescence spectroscopy the reverse reaction, i.e. from supramolecular adduct including dimerized anthracene moieties to depolymerized/free anthracene state again. In this experiment, the intensity of the Fluorescence Emission at 450 nm was recorded at different times, while in the meantime the sample was shed with the 254 nm wavelength in the sample compartment of the fluorescence spectrometer. Spectra were recorded at time 0, 52 min, 120 min and 180 min respectively. A constant increase of the Fluorescence emission Intensity (after 180 min an absolute increase of about 45% of initial value that is due to the residual anthracene monomer still present from Stepl ), indicating that the UV excitation is able to generate again the anthracene moiety which is responsible for the fluorescence emission itself. After 1200 min, total exposition time, a complete conversion of anthracene dimer bond back to anthracene monomer (i.e. full depolymerization) was observed and the fluorescence emission was found to reach a plateau.