EP4551613A1

EP4551613A1 - Polymers containing catechol

Info

Publication number: EP4551613A1
Application number: EP24773044.3A
Authority: EP
Inventors: designation of the inventor has not yet been filed The
Original assignee: Evonik Operations GmbH
Current assignee: Evonik Operations GmbH
Priority date: 2023-09-29
Filing date: 2024-09-19
Publication date: 2025-05-14
Also published as: WO2025068023A1

Abstract

The present invention relates to polymers that comprise 1,2-dihydroxybenzene derivatives, to a method for the preparation thereof, to compositions comprising the polymers, and to the use thereof.

Description

Polymers containing catechol

The present invention relates to polymers that comprise 1 ,2-dihydroxybenzene derivatives, to a method for the preparation thereof, to compositions comprising the polymers, and to the use thereof.

Polymers comprising 1 ,2-dihydroxybenzene derivatives are of particular interest for academic and industrial research and applications, since this structure has been shown inter alia to have unusual adhesion properties.

The inspiration for this structure came from the mussel, which achieves adhesion properties (for example underwater adhesion or adhesion to surfaces coated with polytetrafluoroethylene (PTFE)) unattained industrially. These adhesion properties are explained by the presence of 1 ,2-dihydroxybenzene derivatives within mussel proteins (see Angew. Chem. Int. Ed. 2019, 58, 696-714).

Huge efforts have already been made to obtain a synthetic polymer having similar adhesion properties. These have for this purpose often employed dopamine as a derivative of 1 ,2-dihydroxybenzene having an amine group that is able to react for example with methyl methacrylate. Such a molecule could then react with itself or with other monomers to form a polymer having 1 ,2-dihydroxybenzene derivatives within the repeating unit. Such a synthesis is described for example in Journal of Applied Polymer Science 2003; 89: 1078-84.

Another option for synthesizing polymers comprising 1 ,2-dihydroxybenzene derivatives consists of the synthesis of a monomer having a di hydroxy styrene unit, which can then react with itself or with other monomers such as styrene derivatives or methacrylic derivatives, as described for example in WO 2021/127079.

A drawback with such approaches is that a synthetic derivative of 1 ,2-dihydroxybenzene must first be prepared, which usually involves highly inconvenient synthesis and purification procedures. Furthermore, the polymerization of 1 ,2-dihydroxybenzene derivatives that have polymerizable vinylic double bonds (for example acrylates, methacrylates, styrene derivatives, etc.) necessitates protection of the phenolic OH groups, since these would otherwise undergo undesired side reactions during the polymerization, such as branching and/or crosslinking of the polymer (see Progress in Polymer Science volume 38, issue 1 , January 2013, pages 236-270, Fig. 19). This gives rise to large amounts of waste on account of the numerous additional reaction steps.

US 4499243 describes 1 ,2-dihydroxybenzenes for use in isoprene and butadiene rubber mixtures. Free- radical crosslinking reactions of polyisoprene masterbatches with resorcinol, hydroquinone and catechol are investigated therein, which are carried out with various vulcanization accelerators and elemental sulfur. The vulcanization of polymers with elemental sulfur results in improved properties in the tyres, belts and hoses produced therewith. Another option for preparing polymers comprising 1 ,2-dihydroxybenzene derivatives is the use of already- polymerized monomers bearing active esters, such as esters of pentafluorophenol. In the reaction of such polymers with, for example, dopamine, a functionalization takes place, affording a polymer functionalized with 1 ,2-dihydroxybenzene derivatives, but without the synthesis requiring protecting groups for the phenolic hydroxy groups (see Angewandte Chemie International Edition 2006; 45: 908-12). This approach nevertheless has drawbacks, since the active esters of the monomers must first be formed, which is an inconvenience and a large amount of waste is generated.

The object was therefore to synthesize polymers comprising 1 ,2-dihydroxybenzene derivatives that offer a number of advantages over the prior art: They should offer enhanced or at least equally good adhesion properties on particular surfaces or under particular conditions such as underwater. The surfaces include for example surfaces coated with PTFE. In addition, the preparation of the polymers should be less laborious, with no need for laborious purification. For example, protecting group chemistry should not be necessary. In addition, it should be done with high atom economy.

It has surprisingly been found that this object can be achieved by polymers comprising at least one of the repeating units of the formulas (la)-(lb) groups, H being preferred, and wherein R¹ and R² may be identical or different, and R³, R⁴ = H or OH, preferably where R³ R⁴ and optionally comprising at least one of the repeating units of the formula (lla)-(llc) where n = individually or in total 5 to 4000, preferably 5 to 3000, more preferably 5 to 2000, most preferably 8 to 850.

The polymers of the invention have adhesion properties on different surfaces or under particular conditions such as underwater or difficult-to-bond substrates that are superior or at least equal to those of prior art materials. The surfaces include for example surfaces coated with PTFE, low-energy plastics such as polyethylene and polypropylene, or difficult-to-bond substances, such as polyamides.

It can be advantageous when the polymer comprises repeating units based on further monomers, for example (meth)acrylates, nitriles, styrene or isoprene. These further monomers may be arranged randomly or in blocks. For example, these further monomers provide improved solubility or handling and also better compatibility in compositions of the invention. Copolymers are preferably selected from poly(meth) acrylates, polyacrylonitrile or polystyrene.

The number-average molecular weight of the polymers of the invention is preferably in the range from 1000- 1 000 000 g/mol, particularly preferably 2000-500 000, very particularly preferably 3000-75 000 g/mol.

The number-average molecular weight is determined according to DIN 55672-1 by gel-permeation chromatography in tetrahydrofuran as eluent and polystyrene for calibration.

The polymer may have further functional groups such as aliphatic hydroxyl groups, amines, thiols, halogens, esters, amides, carboxyl groups or C=C double bonds. The further functional groups may be arranged in the polymer (I) randomly or in blocks. Preferably, the further functional groups are randomly distributed.

In a preferred embodiment of the invention, the polymer comprising at least one of the repeating units (la)- (Ib) is prepared through the addition of a monomer of the formula (III) to a polymer comprising at least one of the repeating units selected from (lla)-(llc). The monomer (III) is 1 ,2-dihydroxybenzene or a derivative thereof, that is to say groups, H being preferred, and wherein R¹ and R² may be identical or different, and R³, R⁴ = H or OH, preferably where R³ R⁴.

The addition is to a polymer comprising at least one of the repeating units of the formula (lla)-(llc) to obtain a polymer comprising at least one of the repeating units of the formulas (la)-(lb) where n = 5 to 4000, preferably 5 to 3000, more preferably 5 to 2000, preferably 8 to 850.

In a preferred embodiment, the polymer undergoing the addition is polybutadiene, which may be unfunctionalized or alternatively hydroxy-terminated.

The advantage of this process regime is that the preparation of the polymer is less laborious by comparison with the prior art. For example, neither a multi-stage synthesis nor the use of protecting groups is necessary. The addition makes it possible to ensure high atom economy, since no by-products or leaving groups arise. Furthermore, the monomers (III), for example 1 ,2-dihydroxybenzene, are industrially readily obtainable; there is no need for extensive synthetic steps in preparation for the addition reaction.

The polymers comprising at least one of the repeating units of the formulas (la)-(lb) may be liquid or solid. If present in solid form, they may be crystalline or amorphous.

The polymers (la)-(lb) may be linear or branched in structure. Preferably, these polymers are linear in construction. It follows that the polymers (la)-(lb) of the invention may have a structure that is linear or branched. Preferably, the polymers of the invention are linear in construction.

The polymers may comprise copolymers arranged in blocks, which are preferably selected from the group comprising poly(meth)acrylates, polyacrylonitriles or polystyrenes.

It has been found to be preferable when the repeating units (la)-(lb) and (I la)-(llc) are each independently between 5-100 mol% of the total repeating units in the polymer.

In addition, it was found that the molar ratio of the repeating units (la)-(lb) to the repeating units (lla)-(llc) is preferably in the range 1 :20 to 20:1 .

Under suitable conditions, for example acid catalysis, the double bonds in polymers (lla)-(llc) can be protonated with the formation of an adequately stable carbocation, which can then undergo addition to the aromatic structure of monomer (III) in an electrophilic aromatic substitution.

It is further preferable that the monomer of the formula (III) undergoes addition with 1 to 100 mol% of the C=C double bonds in polymers (lla)-(llc). The description “C=C double bond” encompasses all ethylenic double bonds present in the polymers. Preferably, a degree of functionalization of 3-80 mol%, more preferably of 5-60 mol%, is obtained. In the reaction of polymers (lla)-(llc) with monomer (III), the ratio of monomer (III) to the C=C double bonds in the polymers plays a critical role as regards the subsequent degree of functionalization. Thus, it may be necessary to employ a molar excess of (III) in order to obtain the maximum possible functionalization and, where necessary, to prevent crosslinking. However, with low catalyst amounts and short reaction times it is possible to employ a substoichiometric amount of (III) without crosslinking occurring or the resulting functionalization being too low. The employed molar ratio of C=C double bond in polymers (lla)-(llc) to (III) is usually from 1 :0.05 to 1 :20, preferably from 1 :0.1 to 1 :15, more preferably from 1 :0.2 to 1 :10.

The addition preferably takes place under catalysis, more preferably in the presence of at least one acid. Suitable acids are acids having a pKa at room temperature of < 4, for example sulfuric acid, paratoluenesulfonic acid, hydrochloric acid, acidic ion exchangers or Lewis acids such as indium(lll) trifluoromethanesulfonate. The amount of catalyst used is critical for the success of the reaction. Usually, 0.01-50 mol% of catalyst per C=C double bond is used, preferably 0.1-15 mol%.

The addition can take place in solvent or in the bulk substance. In the bulk substance means that no additional solvents are added. Preferably, the reaction takes place in the bulk substance. Suitable organic solvents for the addition are selected from aprotic solvents, such as dichloromethane, toluene, benzene, tetra hydrofuran, hexane, octane, decane, diethyl ether and the like, and also protic solvents, such as methanol, ethanol, acetone and the like. When using solvents, preference is given to using aprotic solvents, more preferably tetra hydrofuran, dichloromethane or aliphatic hydrocarbons such as hexane or decane.

The addition may take place at various temperatures. Preference is given to using higher temperatures of 40-180°C, particularly preferably 105-180°C.

After preparation of the polymer of the invention, the product should if necessary be separated from unreacted monomer (III). This purification can be effected by drying the reaction mixture and then washing in a solvent in which dissolution of the product or of the reactants is not possible, for example methanol or water. Also possible is precipitation of the product in an organic solvent in which the product is poorly soluble or does not dissolve at all, for example in methanol. Another method for the purification of the product is extraction of the unreacted monomer (III) by aqueous basic solutions, for example dilute sodium hydroxide solution or sodium hydrogen carbonate solution, and subsequent drying of the organic phase. It is also possible to purify the product by disti llation/sublimation, preferably under reduced pressure.

The product is preferably purified by drying the reaction mixture and then adding a selective solvent that removes either the product or unreacted reactants and the catalyst, preferably alkanols having 1-4 carbon atoms, especially methanol.

Likewise preferred is the purification of the product by distillation/sublimation to remove residual monomer (III) from the reaction mixture. It may be necessary to purify the product by washing and drying/sublimation in two separate steps.

The present invention likewise provides for the preparation of the polymers of the invention. This is accomplished by the method of addition of the monomer (III) to polymers selected from (lla)-(llc) already described above. The method of the invention is executed as described above.

The invention also provides compositions comprising at least one polymer comprising at least one of the repeating units of the formulas (la)-(lb) or at least one polymer comprising at least one of the repeating units of the formulas (la)-(lb) prepared according to the invention. The polymer comprising at least one of the repeating units of the formulas (la)-(lb) is present preferably within a range of from 1 % to 50% by weight based on the total weight of the composition. Preference is given to 1 % to 30% by weight and particular preference to 3% to 15% by weight. The polymers are suitable for improving adhesion.

The compositions may be adhesives or sealants, coating materials, foams or lubricants. Adhesives are defined in DIN EN 923:2008-06. Sealants, also termed sealing compounds, refer to substances - generally elastic, applied in liquid to viscous form or as flexible profiles or sheets - used to seal buildings or facilities against water, atmospheric effects or aggressive media, examples being bitumens (asphalt), synthetic resins, foams, mastics, etc., and also (in the case of joint-sealing compounds in particular) silicones, acrylates and polysulfides (Rompp editorial office, Dichtungsmassen [Sealing compounds], RD-04-01300 (2002) in Bockler F., Dill B., Eisenbrand G., Faupel F., Fugmann B., Gamse T., Matissek R., Pohnert G., Ruhling A., Schmidt S., Sprenger G., Rompp [online], Stuttgart, Georg Thieme Verlag, [August 2022] https://roempp.thieme.de/lexicon/RD-04-01300).

Coating materials encompass lacquers, paints and similar products; these are mentioned in DIN ISO 4618. Foams are described in DIN 7726:1982-05. Lubricants is a collective term for substances that reduce friction and (mechanical) stress on machine parts moving against or on top of one another. In doing so, they reduce energy consumption and material wear and in addition act as coolants (see Rompp editorial office, Schmierstoffe [Lubricants], RD-19-01091 (2002) in Bockler F., Dill B., Eisenbrand G., Faupel F., Fugmann B., Gamse T., Matissek R., Pohnert G., Ruhling A., Schmidt S., Sprenger G., Rompp [online], Stuttgart, Georg Thieme Verlag, [August 2022] https://roempp.thieme.de/lexicon/RD-19-01091).

The compositions may comprise customary additives. Those skilled in the art are familiar with the addition of appropriate additives in accordance with the application.

The compositions of the invention may in particular use situations, for example in the adhesives and sealants sector and in coating materials, either be chemically curing, be physically curing or offer a combination of both.

In the case of chemically curing compositions, it is preferable when the polymers of the invention comprising at least one of the repeating units of the formulas (la)-(lb) form a covalent bond to at least one further constituent of the composition during curing, i.e. are reactively incorporated into the composition. These further constituents are selected for example from epoxides, polyurethanes, polysilicones or vulcanizing agents. The polymer undergoes covalent bonding more particularly via the further functional groups such as aliphatic hydroxyl groups, amines, thiols, halogens, esters, amides, carboxyl groups or residual C=C double bonds in the structures (lla)-(llc).

Preference is given to using the polymers of the invention comprising at least one of the repeating units of the formulas (la)-(lb) in adhesives and sealants for improving adhesion to metallic surfaces, mineral surfaces, wet surfaces, glass, wood, silicone, polyolefins (polyethylene, polypropylene and mixtures thereof), rubber and Teflon. Particular preference is given to use on metallic surfaces, mineral surfaces, wet surfaces and also silicone, polyolefins and Teflon.

In coating materials or foams it is conceivable for the polymers of the invention comprising at least one of the repeating units of the formulas (la)-(lb) to be used for improving adhesion properties and wetting. Preference is given to using the polymers of the invention for improving adhesion to metallic surfaces, mineral surfaces, wet surfaces, glass, wood, silicone, polyolefins (especially polyethylene, polypropylene and mixtures thereof), rubber and Teflon. Particular preference is given to use on metallic surfaces, mineral surfaces, wet surfaces and also silicone, polyolefins and Teflon.

When using the compositions of the invention in the adhesives and sealants sector and in coating materials, it is conceivable for the composition of the invention to be used both as a primer and in the main composition.

When using the compositions of the invention in lubricants, it is conceivable for the polymers of the invention comprising at least one of the repeating units of the formulas (la)-(lb) to be used for improving tribological properties by adhering to wear parts, thereby providing better, permanent protection against wear. Preferred materials for these wear parts are for example metals or plastics such as polyaryl ether ketones, especially polyether ether ketone, or polyamide.

The invention further provides for the use of the polymer of the invention comprising at least one of the repeating units of the formulas (la)-(lb), or of a polymer comprising at least one of the repeating units of the formulas (la)-(lb) prepared according to the method of the invention, for improving adhesion. It is used especially in adhesives or sealants, in coating materials, in foams or in lubricants. This use employs the compositions described hereinabove, the properties of which apply by analogy to the use.

Where figures are given in per cent, these are percentages by weight unless otherwise stated. Where average values are stated, for example average molar masses, these are numerical averages unless otherwise stated. Where properties of a material are stated, for example viscosities or the like, these are unless otherwise stated the properties of the material at 25°C and 1013 hPa. Where chemical (empirical) formulas are used in the present invention, the stated indices may represent either absolute numbers or average values. In the case of polymeric compounds, the indices preferably represent average values.

Examples

Polymers used:

Polyvest® 1 10: Liquid polybutadiene without additional functional groups, from Evonik Operations GmbH

Polyvest® HT: Liquid polybutadiene with hydroxy end groups, from Evonik Operations GmbH

Example 1

A 100 ml three-necked flask was first filled with Polyvest® 110 (198 mg, 3.67 mmol of double bonds, 1.00 equiv.) and catechol (3.24 g, 29.4 mmol, 8.00 equiv.). The three-necked flask was equipped with an air condenser and the reaction apparatus was flushed with argon at room temperature. After an inert atmosphere had been created in the apparatus, the reaction mixture was heated to 120°C and stirred until the catechol was completely molten (10 to 15 min). Sulfuric acid (78.0 pL, 1 .47 mmol, 0.40 equiv.) was then added to the reaction solution and this was stirred at 120°C for an additional 30 minutes. After the reaction mixture had cooled to room temperature, the solid residue was taken up in the minimum amount of diethyl ether, washed with water and Na2CO3 solution and then again with water. Finally, the organic phase was dried over Na2SO4, the solvent was removed under reduced pressure and the excess catechol was distilled off by short-path vacuum distillation (Kugelrohr, 120°C to 230°C, 4.2 x 10-2 mbar). The product was obtained as a dark red to black solid and contained a degree of modification of 100%.

Example 2

A 100 ml three-necked flask was first filled with Polyvest® 110 (198 mg, 3.67 mmol of double bonds, 1.00 equiv.) and catechol (3.24 g, 29.4 mmol, 8.00 equiv.). The three-necked flask was equipped with an air condenser and the reaction apparatus was flushed with argon at room temperature. After an inert atmosphere had been created in the apparatus, the reaction mixture was heated to 120°C and stirred until the catechol was completely molten (10 to 15 min). Sulfuric acid (19.5 pL, 0,368 mmol, 0.10 equiv.) was then added to the reaction solution and this was stirred at 120°C for an additional 30 minutes. After the reaction mixture had cooled to room temperature, the solid residue was taken up in the minimum amount of diethyl ether, washed with water and Na2CO3 solution and then again with water. Finally, the organic phase was dried over Na2SO4, the solvent was removed under reduced pressure and the excess catechol was distilled off by short-path vacuum distillation (Kugelrohr, 120°C to 150°C, 4.2 x 10-2 mbar). The product was obtained as a dark red to black viscous substance and contained a degree of modification of 7.4%.

Example 3 A 100 ml three-necked flask was first filled with Polyvest® 110 (198 mg, 3.67 mmol of double bonds, 1.00 equiv.) and catechol (3.24 g, 29.4 mmol, 8.00 equiv.). The three-necked flask was equipped with an air condenser and the reaction apparatus was flushed with argon at room temperature. After an inert atmosphere had been created in the apparatus, the reaction mixture was heated to 120°C and stirred until the catechol was completely molten (10 to 15 min). Sulfuric acid (9.75 pL, 0,184 mmol, 0.05 equiv.) was then added to the reaction solution and this was stirred at 120°C for an additional 30 minutes. After the reaction mixture had cooled to room temperature, the solid residue was taken up in the minimum amount of diethyl ether, washed with water and Na2COs solution and then again with water. Finally, the organic phase was dried over Na2SO4, the solvent was removed under reduced pressure and the excess catechol was distilled off by short-path vacuum distillation (Kugelrohr, 120°C to 150°C, 4.2 x 10-2 mbar). The product was obtained as a dark red to black viscous substance and contained a degree of modification of 1 .4%.

Example 4

A 100 ml three-necked flask was first filled with Polyvest® 110 (198 mg, 3.67 mmol of double bonds, 1.00 equiv.) and catechol (3.24 g, 29.4 mmol, 8.00 equiv.). The three-necked flask was equipped with an air condenser and the reaction apparatus was flushed with argon at room temperature. After an inert atmosphere had been created in the apparatus, the reaction mixture was heated to 120°C and stirred until the catechol was completely molten (10 to 15 min). Phosphoric acid (77.0 pL, 1 .47 mmol, 0.40 equiv.) was then added to the reaction solution and this was stirred at 120°C for an additional 30 minutes. After the reaction mixture had cooled to room temperature, the solid residue was taken up in the minimum amount of diethyl ether, washed with water and Na2COs solution and then again with water. Finally, the organic phase was dried over Na2SO4, the solvent was removed under reduced pressure and the excess catechol was distilled off by short-path vacuum distillation (Kugelrohr, 120°C to 150°C, 4.2 x 10-2 mbar). The product was obtained as a dark red to black viscous substance and contained a degree of modification of 2.1 %.

Example 5

A 100 ml three-necked flask was first filled with Polyvest® HT (198 mg, 3.67 mmol of double bonds, 1.00 equiv.) and catechol (3.24 g, 29.4 mmol, 8.00 equiv.). The three-necked flask was equipped with an air condenser and the reaction apparatus was flushed with argon at room temperature. After an inert atmosphere had been created in the apparatus, the reaction mixture was heated to 120°C and stirred until the catechol was completely molten (10 to 15 min). Sulfuric acid (78.0 pL, 1 .47 mmol, 0.40 equiv.) was then added to the reaction solution and this was stirred at 120°C for an additional 30 minutes. After the reaction mixture had cooled to room temperature, the solid residue was taken up in the minimum amount of diethyl ether, washed with water and Na2COs solution and then again with water. Finally, the organic phase was dried over Na2SO4, the solvent was removed under reduced pressure and the excess catechol was distilled off by short-path vacuum distillation (Kugelrohr, 120°C to 150°C, 4.2 x 10-2 mbar). The product was obtained as a dark red to black viscous substance and contained a degree of modification of 100%. Example 6 (comparative example)

A 250 ml three-necked flask was first filled with Polyvest® 110 (2.83 g, 50.0 mmol of double bonds, 1.00 equiv.) and phenol (37.6 g, 400 mmol, 8.00 equiv.). The three-necked flask was equipped with an air condenser and the reaction apparatus was flushed with argon at room temperature. After an inert atmosphere had been created in the apparatus, the reaction mixture was heated to 120°C and stirred until the catechol was completely molten (10 to 15 min). Sulfuric acid (0.12 g, 1.22 mmol, 2.4 mol% based on double bonds) was then added to the reaction solution and this was stirred at 120°C for an additional 6 hours. After the reaction mixture had cooled to room temperature, the solid residue was analysed directly via NMR. The degree of functionalization of the double bonds was 100%.

Example 7

A 250 ml three-necked flask was first filled with Polyvest® 110 (16.8 g, 300.0 mmol of double bonds, 1.00 equiv.) and catechol (16.5 g, 150 mmol, 0.50 equiv.). The three-necked flask was equipped with an air condenser and the reaction apparatus was flushed with argon at room temperature. After an inert atmosphere had been created in the apparatus, the reaction mixture was heated to 120°C and stirred until the catechol was completely molten (10 to 15 min). Sulfuric acid (0.06 g, 0.6 mmol, 0.2 mol% based on double bonds) was then added to the reaction solution and this was stirred at 120°C for an additional 3 hours. After the reaction mixture had cooled to room temperature, the solid residue was analysed directly via NMR. The degree of functionalization of the double bonds was 23.7%.

Claims

1 . Polymer comprising at least one of the repeating units of the formula (la) or (lb) where

R¹, R² = H or Ci to C4 alkyl groups, H being preferred, and wherein R¹ and R² may be identical or different,

R³, R⁴ = H or OH, preferably where R³ + R⁴ and optionally comprising at least one of the repeating units of the formula (lla)-(llc) where n is individually or in total 5 to 4000, preferably 5 to 3000, more preferably 2000, preferably 8 to 850.

2. Polymer according to Claim 1 , characterized in that the repeating units (la)-(lb) and (lla)-(llc) are between 5-100 mol% of the total repeating units in the polymer.

3. Polymer according to Claim 1 or 2, characterized in that the molar ratio of the repeating units (la)- (Ib) to the repeating units (lla)-(llc) is in the range 1 :20 to 20:1 .

4. Polymer according to any of the preceding claims, characterized in that the polymer has a numberaverage molecular weight, determined according to DIN 55672-1 , in the range from 1000-1 000 000 g/mol.

5. Polymer according to any of the preceding claims, characterized in that further monomers, such as (meth)acrylate, styrene, nitrile, isoprene, are present.

6. Polymer according to any of the preceding claims, characterized in that the polymer comprises copolymers arranged in blocks or randomly, which are preferably selected from poly(meth)acrylate, polyacrylonitrile or polystyrene.

7. Polymer according to any of the preceding claims, characterized in that the polymer is prepared through addition of a monomer of the formula (III) R¹, R² = H or Ci to C4 alkyl groups, H being preferred, and wherein R¹ and R² may be identical or different,

R³, R⁴ = H or OH, where R³ + R⁴, to a polymer comprising at least one of the repeating units of formulas (lla)-(llc) where n is individually or in total 5 to 4000, preferably 5 to 3000, more preferably 2000, preferably 8 to 850.

8. Polymer according to Claim 7, characterized in that the addition takes place under catalysis, preferably in the presence of at least one acid.

9. Method for preparing polymers according to any of the preceding claims through addition of a monomer of the formula (III) where

R³, R⁴ = H or OH, where R³ + R⁴, to a polymer comprising at least one of the repeating units of formulas (lla)-(llc), characterized in that the addition takes place under catalysis, preferably in the presence of at least one acid.

10. Composition comprising at least one polymer comprising at least one of the repeating units of the formula (la)-(lb) according to any of Claims 1 to 8 or prepared according to Claim 9.

11. Composition according to claim 10, wherein the polymer comprising at least one of the repeating unit of the formula (la)-(lb) forms a covalent bond to at least one further constituent of the composition during curing.

12. Use of a polymer comprising at least one of the repeating units of the formula (la)-(lb) according to any of Claims 1 to 8, or prepared according to Claim 9, for improving adhesion.

13. Use according to Claim 12 in adhesives or sealants, in coating materials, in foams or in lubricants.

14. Use according to Claims 12 or 13, wherein the polymer comprising at least one of the repeating units of the formula (la)-(lb) forms a covalent bond to at least one further constituent of the composition during curing.