Method for synthesising a polymer having a hydroxyaryl group, product obtained using said method and composition containing same

Abstract

The invention relates to a process for the synthesis of a polymer bearing one or more pendant hydroxyaryl groups, comprising the reaction of a polymer bearing at least one epoxide functional group with a nucleophilic compound simultaneously bearing the hydroxyaryl group and a nucleophilic functional group selected from the group consisting of the phosphonic acid functional group and its ionic form.

Claims

1. A process for the synthesis of a polymer bearing at least one pendant hydroxyaryl group, which process comprises the reaction of a starting polymer bearing at least one epoxide functional group with a nucleophilic compound simultaneously bearing the hydroxyaryl group and bearing a nucleophilic functional group selected from the group consisting of the phosphonic acid functional group and its ionic form.

2. A process according to claim 1, in which the hydroxyaryl group is an aryl group which bears two hydroxyl functional groups directly bonded to the benzene ring.

3. A process according to claim 1, in which the nucleophilic functional group is the phosphonic monoacid functional group.

4. A process according to claim 3, in which the nucleophilic functional group is the P(O)(OR)(OH) group, and R is an alkyl.

5. A process according to claim 1, in which the nucleophilic compound corresponds to the following formula (I):
A-BX(I) in which: A represents a nucleophilic functional group selected from the group consisting of the phosphonic acid functional group and its ionic form, B is a spacer representing an atom or a group of atoms forming a connection between A and X, X represents an aryl group bearing from 1 to 5 hydroxyl functional groups directly bonded to the benzene ring.

6. A process according to claim 5, in which B in the formula (I) represents a divalent hydrocarbon chain which can be substituted or interrupted by at least one heteroatom.

7. A process according to claim 5, in which X in the formula (I) represents: ##STR00008## in which the Ri groups, which are identical or different, represent a hydrogen atom or a hydroxyl group, at least one of the Ri groups representing a hydroxyl group.

8. A process according to claim 7, in which two Ri groups each represent a hydroxyl group, the other Ri groups each representing a hydrogen atom.

9. A process according to claim 8, in which X in the formula (I) represents an aryl group substituted on two neighbouring carbon atoms by two hydroxyl functional groups.

10. A process according to claim 9, in which X in the formula (I) represents: ##STR00009##

11. A process according to claim 10, in which the nucleophilic compound corresponds to the formula: ##STR00010##

12. A process according to claim 1, in which the two carbon atoms of the epoxide functional group are in the main chain of the starting polymer.

13. A process according to claim 12, in which the starting polymer contains 1,4-diene units, a portion of which is epoxidized.

14. A process according to claim 13, in which the 1,4-diene units are 1,4-butadiene or 1,4-isoprene units.

15. A process according to claim 13, in which the starting polymer containing 1,4-diene units results from the epoxidation of a portion of a polymer selected from the group consisting of polybutadienes, polyisoprenes, 1,3-butadiene copolymers, isoprene copolymers and the mixtures of these polymers; and a portion of the 1,4-diene units of the starting polymer is epoxidized.

16. A process according to claim 1, in which the epoxide functional group is pendant.

17. A process according to claim 16, in which the starting polymer is a polymer at least of a first monomer bearing the epoxide functional group.

18. A process according to claim 17, in which the starting polymer is a polymer at least of a first monomer bearing the epoxide functional group and of a second monomer.

19. A process according to claim 18, in which the second monomer is a vinyl monomer chosen from: ethylene, -olefins, (meth)acrylonitrile, (meth)acrylates, vinyl esters of carboxylic acids, vinyl alcohol, vinyl ethers, and the mixtures of these monomers.

20. A process according to claim 18, in which the second monomer is ethylene.

21. A process according to claim 18, in which the second monomer is an -monoolefin, a conjugated diene or a non-conjugated diene.

22. A process according to claim 21, in which the second monomer is 1,3-butadiene, isoprene, their mixture or styrene.

23. A process according to claim 18, in which the starting polymer is a polymer at least of a first monomer bearing the epoxide functional group, of ethylene or of an -olefin and of a third monomer, which third monomer is a vinyl monomer chosen from: ethylene, -olefins, (meth)acrylonitrile, (meth)acrylates, vinyl esters of carboxylic acids, vinyl alcohol, vinyl ethers, and the mixtures of these monomers.

24. A process according to claim 17, in which the first monomer bearing the epoxide functional group is a monomer bearing an epoxide functional group.

25. A process according to claim 24, in which the first monomer is a monomer bearing a glycidyl group, and the first monomer is a glycidyl ester of an ,-unsaturated carboxylic acid.

26. A process according to claim 16, in which the starting polymer is obtained by postpolymerization modification of an unsaturated polymer by an epoxidized compound.

27. A process according to claim 26, in which the unsaturated polymer is one of the diene elastomers (a) to (e): (a) a homopolymer of a conjugated diene monomer having from 4 to 12 carbon atoms, (b) a copolymer of a conjugated diene monomer having from 4 to 12 carbon atoms, (c) a homopolymer of a non-conjugated diene monomer having from 5 to 12 carbon atoms, (d) a copolymer of a non-conjugated diene monomer having from 5 to 12 carbon atoms, (e) a mixture of the polymers defined in (a) to (d).

28. A process according to claim 27, in which the unsaturated polymer is a diene elastomer selected from the group consisting of polybutadienes, polyisoprenes, butadiene copolymers, isoprene copolymers and their mixtures.

29. A process according to claim 1, in which the content of epoxide functional group in the starting polymer is at least 0.1 mol per 100 mol of monomer units constituting the starting polymer.

30. A polymer bearing at least one pendant hydroxyaryl group capable of being obtained by the synthesis process defined according to claim 1.

31. A polymer according to claim 30, which polymer is an elastomer.

32. A rubber composition based at least on a reinforcing filler and on a polymer defined according to claim 30.

33. A tire which comprises a rubber composition according to claim 32.

34. A process according to claim 25, wherein the first monomer is glycidyl methacrylate, glycidyl acrylate or glycidyl itaconate.

Description

EXAMPLES

(1) 1Measurements Used:

(2) II.1.1Nuclear Magnetic Resonance (NMR):

(3) The microstructure of the polymers, in particular the content of the different monomer units in the polymers, is determined by NMR analysis. The .sup.1H NMR analyses are carried out with a Bruker Avance 300 (300 MHz) spectrometer, QNP .sup.1H, .sup.31P, .sup.19F and .sup.13C probe. The samples are dissolved in deuterated chloroform (CDCl.sub.3).

(4) 1.2Size Exclusion Chromatography (SEC):

(5) Size exclusion chromatography (SEC) is used. SEC makes it possible to separate macromolecules in solution according to their size through columns filled with a porous gel. The macromolecules are separated according to their hydrodynamic volume, the bulkiest being eluted first.

(6) Without being an absolute method, SEC makes it possible to comprehend the distribution of the molar masses of a polymer. The various number-average molar masses (Mn) and weight-average molar masses (Mw) can be determined from commercial standards and the polymolecularity or polydispersity index (PI=Mw/Mn) can be calculated via a Moore calibration.

(7) Preparation of the polymer: There is no specific treatment of the polymer sample before analysis. The latter is simply dissolved, in tetrahydrofuran+1 vol % of diisopropylamine+1 vol % of triethylamine+0.1 vol % of distilled water, at a concentration of approximately 1 g/l. The solution is then filtered through a filter with a porosity of 0.45 m before injection.

(8) SEC analysis: The apparatus used is a Waters Alliance chromatograph. The elution solvent is tetrahydrofuran+1 vol % of diisopropylamine+1 vol % of triethylamine according to the solvent used for the dissolution of the polymer. The flow rate is 0.7 ml/min, the temperature of the system is 35 C. and the analytical time is 90 min. A set of four Waters columns in series, with commercial names Styragel HMW7, Styragel HMW6E and two Styragel HT6E, is used.

(9) The volume of the solution of the polymer sample injected is 100 l. The detector is a Waters 2410 differential refractometer and the software for making use of the chromatographic data is the Waters Empower system.

(10) The calculated average molar masses are relative to a calibration curve produced from PSS Ready Cal-Kit commercial polystyrene standards.

(11) 2Preparation of Polymers Bearing Epoxide Groups:

Example 1: Epoxidation of Polyisoprene LIR 30000 with MCPBA

(12) ##STR00004##

(13) 50 g of LIR 30000 and 300 ml of dichloromethane are introduced into a two-necked round-bottomed flask. The mixture is placed under stirring at 0 C. and 8.22 g of meta-chloroperbenzoic acid in solution in 75 ml of chloroform are then introduced dropwise using a dropping funnel. The mixture is subsequently left stirring at ambient temperature for 4 h. At the end of the reaction, the copolymer is precipitated twice from 2 liters of ethanol and then dissolved in dichloromethane. The solvent is then completely removed by evaporation under vacuum. The final product is a translucent viscous liquid obtained with a yield of 96%. It is analysed by .sup.1H NMR.

(14) The .sup.1H NMR spectrum makes it possible to quantify the microstructure within the copolymer by integration of signals characteristic of the protons 1 and 2 which appear in the form of broad unresolved peaks:

(15) ##STR00005##

(16) TABLE-US-00001 Proton No. Chemical shift (ppm) Number of protons H2 2.72 1 H1 4.64-5.28 1

(17) The molar composition of the copolymer is as follows: 4.1 mol % of epoxide and 95.9 mol % of isoprene. The molar mass of the copolymer is 30 210 g/mol. There are approximately 18 epoxide functional groups per chain.

(18) 3Preparation of Polymers Bearing Pendant Hydroxyaryl Groups Along the Chain:

Example 2

(19) ##STR00006##

(20) 18 g of epoxidized polyisoprene, 4.82 g of 11-[ethoxy(hydroxy)phosphoryl]undecyl 3-(3,4-dihydroxyphenyl)propanoate and 50 ml of dioxane are introduced into a single-necked round-bottomed flask. The reaction medium is stirred magnetically and heated at 90 C. for 24 hours. At the end of the reaction, the terpolymer is precipitated twice from methanol and then dissolved in dichloromethane. The solvent is then completely removed by evaporation under vacuum. The final product is a translucent yellow polymer obtained with a yield of 91%. It is analysed by .sup.1H and .sup.31P NMR.

(21) The .sup.1H NMR spectrum makes it possible to quantify the microstructure within the copolymer by integration of signals characteristic of the protons 1 to 9 which appear in the form of broad unresolved peaks:

(22) ##STR00007##

(23) TABLE-US-00002 Proton No. Chemical shift (ppm) Number of protons H5 2.59 2 H1 2.72 1 H6 2.84 2 H4 4.08 2 H3 4.33 1 H2 4.64-5.28 1 H7 H8 H9 6.54-6.84 3

(24) The .sup.31P NMR spectrum makes it possible to observe the signal characteristic of the grafted phosphorus at 47.7 ppm.

(25) The molar composition of the terpolymer is as follows: 96.5 mol % of isoprene, 2.5 mol % of catechol and 1 mol % of residual epoxide. The molar mass of the copolymer is 35 070 g/mol. There are approximately 11 catechol functional groups per chain.