Metallopolymers and use thereof

Abstract

Metallopolymers of formula (I) where R.sup.1 and R.sup.1′; and R.sup.2 and R.sup.2′ are independently of each other, a C.sub.2-C.sub.10 alkyl group; X is CR3R3′ or NR4; R.sup.3 and R.sup.3′ are, independently of each other, as is R.sup.4, a C.sub.2-C.sub.10 alkyl group; L is a C.sub.4-C.sub.10 alkylene group; Ln.sup.1 and Ln.sup.2 are, independently of each other, chosen from the lanthanide cations; L.sup.1 and L.sup.2 are, independently of each other, chosen from the α-diketonate ligands; T is a neutral bidentate Lewis base including two coordinating nitrogen atoms; .fwdarw. represents a coordination of group T via the two nitrogen atoms of T to Ln.sup.1 and Ln.sup.2 respectively; Ln.sup.1 and Ln.sup.2 are, independently of each other, chosen from the lanthanide cations; L.sup.1 and L.sup.2 are, independently of each other, chosen from the β-diketonate, picolinate or dipicolinate monoanionic ligands; 0.01<x<0.50; 0<y<0.49, with x+y=0.50.

Claims

1. A metallopolymer consisting_of repeat units of Formula I ##STR00019## in which R.sup.1 and R.sup.1′ are, independently of one another, a C.sub.2-C.sub.10 alkyl group; R.sup.2 and R.sup.2′ are, independently of one another, a C.sub.2-C.sub.10 alkyl group; X is CR.sup.3R.sup.3′ or NR.sup.4; R.sup.3 and R.sup.3′ are, independently of one another, a C.sub.2-C.sub.10 alkyl group; R.sup.4 is a C.sub.2-C.sub.10 alkyl group; L is a C.sub.4-C.sub.10 alkylene group; T is a neutral bidentate Lewis base that comprises two coordinating nitrogen atoms; .fwdarw. shows a coordination of the group T via the two nitrogen atoms from T to Ln.sup.1 and Ln.sup.2 respectively; Ln.sup.1 and Ln.sup.2 are, independently of one another, selected from among the lanthanide cations; L.sup.1 and L.sup.2 are, independently of one another, selected from among the β-diketonate, picolinate or dipicolinate monoanionic ligands; x is from 0.01 to 0.50; y is from 0 to 0.49, with the sum of x +y being equal to 0.50.

2. The metallopolymer according to claim 1, consisting of repeat units of Formula IA ##STR00020## in which R.sup.1, R.sup.1′, R.sup.2, R.sup.2′, R.sup.3, R.sup.3′, L, T, Ln.sup.1, Ln.sup.2, L.sup.1, L.sup.2, x and y are as previously defined.

3. The metallopolymer according to claim 1, consisting of repeat units of Formula IB ##STR00021## in which R.sup.1, R.sup.1′, R.sup.2, R.sup.2′, R.sup.4, L, T, Ln.sup.1, Ln.sup.2, L.sup.1, L.sup.2, x, y, and n are as previously defined.

4. The metallopolymer according to claim 1, consisting of repeat units of Formula I′ ##STR00022## in which R.sup.1, R.sup.1′, R.sup.2, R.sup.2′, X, L, Ln.sup.1, Ln.sup.2, L.sup.1, L.sup.2, x and y are as previously defined.

5. The metallopolymer according to claim 1, in which R.sup.1 and R.sup.1′ are n-octyl.

6. The metallopolymer according to claim 1, in which R.sup.2 and R.sup.2′ are n-octyl.

7. The metallopolymer according to claim 1, in which L is n-butylene.

8. The metallopolymer according to claim 1, in which Ln.sup.1 and Ln.sup.2 are both Eu.sup.3+, and L.sup.1 and L.sup.2 are both thenoyltrifluoroacetonate.

9. The metallopolymer according to claim 1, in which Ln.sup.1 is Eu.sup.3+ and Ln.sup.2 is Tb.sup.3+, and L.sup.1 and L.sup.2 are both thenoyltrifluoroacetonate.

10. A conjugated polymer consisting of repeat units of Formula II ##STR00023## in which R.sup.1 and R.sup.1′ are, independently of one another, a C.sub.2-C.sub.10 alkyl group; R.sup.2 and R.sup.2′ are, independently of one another, a C.sub.2-C.sub.10 alkyl group; X is CR.sup.3R.sup.3′ or NR.sup.4; R.sup.3 and R.sup.3′ are, independently of one another, a C.sub.2-C.sub.10 alkyl group; R.sup.4 is a C.sub.4-C.sub.10 alkyl group; x is from 0.01 to 0.50; y is from 0 to 0.49, with the sum of x +y being equal to 0.50; L is a C.sub.4-C.sub.10 alkylene group; T is a neutral bidentate Lewis base that comprises two coordinating nitrogen atoms.

11. A method of manufacturing a polymer light-emitting diode which comprises placing a metallopolymer according to claim 1 between an anode and a cathode.

12. A light-emitting_diode comprising a layer of a metallopolymer according to claim 1.

13. The metallopolymer_according to claim 2, in which R.sup.1 and R.sup.1′ are n-octyl.

14. The metallopolymer_according to claim 2, in which R.sup.2 and R.sup.2′ are n-octyl.

15. The metallopolymer according to claim 2, in which L is n-butylene.

16. The metallopolymer_according to claim 2, in which Ln.sup.1 and Ln.sup.2 are both Eu.sup.3+, and L.sup.1 and L.sup.2 are both thenoyltrifluoroacetonate.

17. The metallopolymer.sub.-—according to claim 2, in which Ln.sup.1 is Eu.sup.3+ and Ln.sup.2 is Tb.sup.3+, and L.sup.1 and L.sup.2 are both thenoyltrifluoroacetonate.

Description

DESCRIPTION OF THE FIGURES

(1) FIG. 1 is a diagrammatic representation of a multilayer organic light-emitting diode of the state of the art.

(2) FIG. 2 shows a comparison of the ATG curves of the two metal complexes: [Eu(tta).sub.3(H.sub.2O).sub.2], [Eu(tta).sub.3(L)], with that of the metallopolymer of Example 5 and that of the corresponding conjugated polymer.

(3) FIG. 3 shows a comparison of the ATG curves of the two metal complexes: [Eu(tta).sub.3(H.sub.2O).sub.2], [Eu(tta).sub.3(L)], with that of the metallopolymer of Example 6 and that of the corresponding conjugated polymer.

(4) FIG. 4 shows the emission spectrum in solution of the metallopolymer of Example 5.

(5) FIG. 5 shows the emission spectrum in solution of the metallopolymer of Example 6.

(6) FIG. 6 shows the thin-film emission spectrum of the metallopolymer of Example 6.

(7) FIG. 7 is a diagrammatic representation of a light-emitting diode of Example 9.

(8) FIG. 8 shows the light-emitting spectrum of a polymer light-emitting diode according to the invention.

EXAMPLES

(9) The steric exclusion chromatography (SEC) analyses were carried out on a Malvern Discotek GPC/SEC device equipped with a UV detector and a refraction index variation detector.

(10) The thermogravimetric analyses were carried out on a Netzsch STA 409 PC Luxx® analyzing device under a stream of nitrogen. The decomposition temperature was evaluated for a loss of mass of 5%.

(11) The photoluminescence spectra were recorded on a Jobin Yvon Fluoromax4 spectrometer. The measurements of photoluminescence yield in solution were made on a Jobin Yvon Fluorolog3 spectrometer equipped with an integration sphere.

Synthesis of 3,6-dibromo-9-(4-(2-pyridin-2-yl-benzoimidazol-1-yl)-butyl)-9H-carbazole

(12) ##STR00013##

First Synthesis Stage: 3,6-Dibromo-9-(4′-bromobutyl)carbazole (1)

(13) ##STR00014##

Diagram 1: Synthesis of 3,6-dibromo-9-(6′-bromobutyl)carbazole (1)

(14) In a glovebox, 2 g (6.2 mmol) of 3,6-dibromocarbazole is dissolved in 20 ml of anhydrous THF. 295 mg (12.3 mmol) of sodium hydride is then added by small quantities to the solution. The addition of this compound brings about a strong release of gas linked to the formation of dihydrogen, entrained by the deprotonation of the 3,6-dibromocarbazole. 2.2 ml (18.5 mmol) of 1,4-dibromobutane is then added to the reaction medium using a syringe. The injection is done under a stream of argon. The reaction is carried out under inert atmosphere. The reaction mixture is stirred for 12 hours and then brought to reflux. Excess NaH is then eliminated by filtration. An extraction by dichloromethane is carried out on the filtrate. The organic phase is dried using magnesium sulfate, and the solvent is evaporated under vacuum after filtration. Finally, the final product (1) is obtained by recrystallization in ethanol. The synthesized compound is a beige solid that is obtained with a yield of 49%.

(15) This compound was characterized by .sup.1H NMR. The spectrum of 3,6-dibromo-9-(4′-bromobutyl)carbazole is provided in Attachment 1: 8.10 ppm (d, 2H, .sup.4J=1.8 Hz, H1 and H4), 7.54 ppm (dd, 2H, .sup.3J=8.7 Hz, .sup.4J=1.8 Hz, H2 and H5), 7.23 ppm (d, 2H, .sup.3J=8.7 Hz, H3 and H6), 4.25 ppm (t, 2H, .sup.3J=6.3 Hz, H7 and H8), 3.36 ppm (t, 2H, .sup.3J=6.3 Hz, H13 and H14), 1.93 ppm (m, 4H, H9, H10, H11 and H12).

Second Synthesis Stage: 3,6-Dibromo-9-(4-(2-pyridin-2-yl-benzoimidazol-1-yl)-butyl)-9H-carbazole (2)

(16) ##STR00015##

Diagram 2: Synthesis of 3,6-dibromo-9-(4-(2-pyridin-2-yl-benzoimidazol-1-yl)-butyl)-9H-carbazole (2)

(17) The synthesis of this compound is carried out under inert atmosphere. 369 mg (1.89 mmol) of 2-(2-pyridyl)benzimidazole is dissolved in advance in 20 ml of anhydrous DMF. 113 mg (2.84 mmol) of sodium hydroxide and then 870 mg (1.89 mmol) of 3,6-dibromo-9-(6′-bromobutyl)carbazole are added to the reaction medium that is brought to reflux and stirred for 12 hours. An extraction by dichloromethane is then carried out. The organic phase is dried on magnesium sulfate. A portion of the solvent of the organic phase is evaporated under vacuum after filtration, and the compound recrystallizes under cold conditions in a very concentrated solution; it is obtained with a yield of 74%.

(18) The overall yield that comprises the two synthesis stages presented above is 47%.

(19) The .sup.1H NMR spectrum of the compound 2 was recorded in the deuterated chloroform. It demonstrates the presence of two groups of signals: those of the hydrogen atoms of the alkyl chain and the signals of the aromatic hydrogen atoms of carbazole and of the pyridyl-benzimidazole group: 8.54 ppm (d, 1H, .sup.4J=4.8 Hz, Py-H), 8.43 ppm (d, 1H, .sup.3J=7.9 Hz, Py-H), 8.10 ppm (d, 2H, .sup.4J=1.8 Hz, H1 and H4), 7.87 ppm (td, 2H, Py-H), 7.54 ppm (dd, 2H, .sup.3J=8.7 Hz, .sup.4J=1.8 Hz, H2 and H5), 7.39 ppm (m, 4H, Ar—H), 7.23 ppm (d, 2H, .sup.3J=8.7 Hz, H3 and H6), 4.80 ppm (t, 2H, .sup.3J=6.3 Hz, H13 and H14), 4.25 ppm (t, 2H, .sup.3J=6.3 Hz, H7 and H8), 1.93 ppm (m, 4H, H9, H10, H11 and H12).

Synthesis of 3,6-dibromo-9-hexyl-9H-carbazole (3)

(20) ##STR00016##

Diagram 3: Synthesis of 3,6-dibromo-9-hexyl-9H-carbazole (3)

(21) In a glovebox, 1.5 g (4.6 mmol) of 3,6-dibromocarbazole is dissolved in 15 ml of anhydrous THF. 221 mg (9.2 mmol) of sodium hydride is then added by small quantities to the solution so as to prevent too violent a release of gas that is linked to the formation of dihydrogen, caused by the deprotonation of 3,6-dibromocarbazole. 1.7 ml (13.8 mmol) of 1-bromohexane is then injected into the reaction medium under a stream of argon. The reaction is carried out under inert atmosphere. The reaction mixture is stirred for 12 hours and brought to reflux at a temperature of 65° C. Excess NaH is then eliminated by filtration. An extraction by dichloromethane is carried out on the filtrate. The organic phase is dried on magnesium sulfate, and the solvent is evaporated under vacuum. The compound that is obtained comes in the form of dark beige crystals. The yield is 60%.

(22) The .sup.1H NMR spectrum of 3,6-dibromo-9-(6′-bromobutyl)carbazole was recorded in the deuterated chloroform: 8.10 ppm (d, 2H, .sup.4J=1.8 Hz, H1 and H4), 7.54 ppm (dd, 2H, .sup.3J=8.7 Hz, .sup.4J=1.8 Hz, H2 and H5), 7.23 ppm (d, 2H, .sup.3J=8.7 Hz, H3 and H6), 4.25 ppm (t, 2H, .sup.3J=6.3 Hz, H7 and H8), 2.1 ppm (t, 2H, .sup.3J=6.3 Hz, H15 and H16), 1.93 pm (m, 6H, H9, H10, H11, H12, H13, H14), 0.8 ppm (m, 3H, H17, H18, H19).

Synthesis of tris(2-thenoyltrifluoroacetonato)bis(aquo)europium (III): [Eu(tta)3(H2O)2] (4)

(23) ##STR00017##

Diagram 4: Synthesis of tris(2-thenoyltrifluoroacetonato)europium(III) dihydrate (4)

(24) 1 g of Htta (4.5 mmol) is dissolved in 20 ml of absolute ethanol. 4.5 ml of an aqueous solution of sodium hydroxide with a concentration of C=1 mol.Math.L.sup.−1 is added to the reaction medium so as to make possible the deprotonation of β-diketone. The mixture is then stirred for one hour. 550 mg of hexahydrated europium chloride (1.5 mmol) is dissolved in 50 ml of distilled water. This solution is slowly added to the β-diketonate solution. The reaction mixture is finally stirred for 12 hours at 60° C. A precipitate that is light yellow in color forms. It is recovered by filtration and then dried under vacuum. The yield is 71%.

Synthesis of tris(2-thenoyltrifluoroacetonato){3,6-Dibromo-9-(4-(2-pyridin-2-yl-benzoimidazol-1-yl)-butyl)-9H-carbazole}europium(III): [Eu(tta)3L] (5) (with L for {3,6-Dibromo-9-(4-(2-pyridin-2-yl-benzoimidazol-1-yl)-butyl)-9H-carbazole})

(25) Tris(2-thenoyltrifluoroacetonato) {3,6-dibromo-9-(4-(2-pyridin-2-yl-benzoimidazol-1-yl)-butyl)-9H-carbazole}europium(III) is obtained by reaction between the compound 4 and the compound 2 in THF under inert atmosphere (Diagram 5).

(26) ##STR00018##

Diagram 5: Synthesis of the Eu(tta)3L Complex (5)

(27) In a glovebox, a solution of 1 g (1.16 mmol) of the Eu(tta).sub.3(H.sub.2O).sub.2 complex in 10 ml of anhydrous THF is slowly added to a solution of 0.67 g of 3,6-dibromo-9-(4-(2-pyridin-2-yl-benzoimidazol-1-yl)-butyl)-9H-carbazole (1.16 mmol) in 5 ml of anhydrous THF. The reaction medium is then stirred for 12 hours at 60° C. Successive additions of several milliliters of pentane entrain the formation of a precipitate that is recovered by filtration and then dried under vacuum. The compound that is obtained is a powder that is clear beige in color, and the yield of the reaction is 51%.

(28) The complex was characterized by elementary analysis.

(29) AE: Calculated for: C.sub.52H.sub.34Br.sub.2EuF.sub.9N.sub.4O.sub.6S.sub.3: C, 44.94%; H, 2.47%; N, 4.03%. Found: C, 44.95%; H, 2.34%; N, 4.03%.

Example 1

Synthesis of a Conjugated Polymer of Formula IIA with x=0.35 and y=0.15

(30) The palladium (0) catalyst Pd (OAc).sub.2 was formed in situ from 2.2 mg (17.8 μmol) of palladium acetate (II) and 8.9 mg (53.9 μmol) of tri-p-tolylphosphine in 15 ml of toluene. 438 mg (0.87 mmol) of bipinacolic ester of the 2,7-diboronic acid of 9,9-di-n-hexylfluorene, 350 mg (0.61 mmol) of 3,6-dibromo-9-(4-(2-pyridin-2-yl-benzoimidazol-1-yl)-butyl)-9H-carbazole, 79 mg (0.16 mmol) of 9,9-dihexyl-2,7-dibromofluorene, as well as 4.5 ml of an aqueous solution of tetraethylammonium hydroxide at 20% were added to the toluene solution that contains the catalyst. The reaction medium was brought to reflux at 120° C. for 72 hours. So as to terminate the polymer chain, 54 μl(51 μmol) of bromobenzene and 67 mg (55 μmol) of phenylboronic acid ester were successively added at 5-hour intervals. The reaction mixture that was obtained was introduced drop by drop into 200 ml of methanol. The gray precipitate was recovered by filtration and then dissolved in chloroform (50 ml). The solution was again added drop by drop into 200 ml of methanol. The solid was separated from the methanol solution by filtration and then washed with acetone in a Soxhlet for 48 hours.

(31) The conjugated polymer that was obtained was characterized by steric exclusion chromatography (SEC): M.sub.n=5,979, M.sub.w=8,371, Polydispersity index I=1.4.

Example 2

Synthesis of Conjugated Polymers of Formula IIA with Different Levels of Functionalized Carbazole

(32) The following polymers of formula IIA were synthesized according to the operating mode of Example 1 by using different levels of the monomers used in Example 1: x=0.01 and y=0.49; x=0.05 and y=0.45; x=0.1 and y=0.4; x=0.2 and y=0.3; x=0.35 and y=0.15.

(33) The conjugated polymers that were obtained were characterized by steric exclusion chromatography (SEC). The results are shown in Table 1 below.

(34) TABLE-US-00001 TABLE 1 Molecular Molecular Weight by Weight by Polydispersity x y Number (Mn) Mass (Mw) Index (I) 0.01 0.49 17,560 27,043 1.5 0.05 0.45 17,727 38,747 2.2 0.10 0.40 22,593 60,835 2.7 0.20 0.30 8,997 10,210 1.1

Example 3

Synthesis of a Conjugated Polymer of Formula IIB with x=0.2 and y=0.3

(35) The palladium (0) catalyst is formed in situ from 2.0 mg (15 μmol) of palladium (II) acetate and 8.2 mg (49.6 μmol) of tri-p-tolylphosphine in 10 ml of toluene. 91 mg (0.158 mmol) of 3,6-dibromo-9-(4-(2-pyridin-2-yl-benzoimidazol-1-yl)-butyl)-9H-carbazole and 98 mg (0.239 mmol) of 3,6-dibromo-9-hexyl-9H-carbazole are then added to the toluene solution. In a glovebox, 16 mg of Aliquat 336 is dissolved in 5 ml of toluene and injected under a stream of argon into the reaction medium. 255.5 mg (0.397 mmol) of bipinacolic ester from 9,9-di-n-hexylfluorene 2,7-diboronic acid and 1.5 ml of an aqueous solution of potassium carbonate with a concentration of C=2 mol.Math.L.sup.−1 are then added to the reaction medium that is stirred and brought to 120° C. for 72 hours. Finally, 24 μl (23 μmol) of bromobenzene and 29 mg (24 μmol) of phenylboronic acid ester are successively added at 5-hour intervals. The reaction mixture is added drop by drop into 200 ml of methanol. The solid is recovered by filtration and then dissolved in chloroform (50 ml). The solution is again added drop by drop into 200 ml of methanol. The solid conjugated polymer is recovered by filtration, dried, and then washed by acetone in a Soxhlet for 48 hours.

(36) The conjugated polymer that is obtained was characterized by steric exclusion chromatography (SEC): M.sub.n=6,553, M.sub.w=10,121, polydispersity index I=1.5.

Example 4

Synthesis of a Conjugated Polymer of Formula IIB with Different Levels of Functionalized Carbazole

(37) The following polymers of Formula IIB were synthesized according to the operating mode of Example 3 by using different levels of the monomers used in Example 3: x=0.01 and y=0.49; x=0.05 and y=0.45; x=0.10 and y=0.40; x=0.35 and y=0.15; x=0.50 and y=0.

(38) The conjugated polymers that were obtained were characterized by steric exclusion chromatography (SEC). The results are presented in Table 2 below.

(39) TABLE-US-00002 TABLE 2 Molecular Weight Molecular Weight Polydispersity Levels (x; y) by Number (Mn) by Mass (Mw) Index (I) 0.01; 0.49 8,998 13,242 1.5 0.05; 0.45 5,831 6,845 1.2 0.10; 0.40 6,098 8,591 1.4 0.20; 0.30 6,553 10,121 1.5 0.35; 0.15 7,837 11,602 1.5 0.50; 0.00 5,547 8,229 1.5

Example 5

Synthesis of a Metallopolymer of Formula IA with x=0.35 and y=0.65

(40) In a glovebox, 100 mg of the conjugated polymer of Example 1 was dissolved in 10 ml of anhydrous chloroform. A solution that contains 100 mg (117 mmol) of [Eu(tta).sub.3(H.sub.2O).sub.2] in 10 ml of anhydrous chloroform was added drop by drop to the one containing the organic polymer. The mixture was then stirred for 12 hours at 60° C. There is a large excess of the [Eu(tta).sub.3(H.sub.2O).sub.2] complex relative to the quantity of sites to be coordinated within the polymer chain so as to force the coordination of the metal complex on all of the sites. The solvent was evaporated under vacuum. The thus recovered solid was washed by small portions of cold methanol so as to eliminate excess [Eu(tta).sub.3(H.sub.2O).sub.2]. It was recovered by filtration and then dried.

(41) The metallopolymer that was obtained was characterized by steric exclusion chromatography (SEC): M.sub.n=6,811, M.sub.w=8,696, polydispersity index I=1.3.

(42) The measured mean molar mass by number (M.sub.n) is greater than the one recorded for the initial conjugated polymer. This means that the hydrodynamic volume (space occupied by the macromolecules in solution) of the metallopolymers is higher than that of the conjugated polymers that have served in their synthesis. This can be explained by a steric impediment induced by the presence of Eu(tta).sub.3 groups within polymer chains. This therefore constitutes a good indication that the metal complex was well coordinated within polymer chains.

Example 6

Synthesis of a Metallopolymer of Formula IB with x=0.2 and y=0.3

(43) In a glovebox, 100 mg of the conjugated polymer of Example 3 was dissolved in 10 ml of anhydrous chloroform. A solution that contains 60 mg (51 mmol) of [Eu(tta).sub.3(H.sub.2O).sub.2] in 5 ml of anhydrous chloroform was added drop by drop to the one that contains the organic polymer. The mixture was then stirred for 12 hours at 60° C. There is a large excess of the [Eu(tta).sub.3(H.sub.2O).sub.2] complex relative to the quantity of sites to be coordinated within the polymer chain so as to force the coordination of the metal complex on all of the sites. The solvent was evaporated under vacuum. The thus recovered solid was washed by small portions of cold methanol so as to eliminate the excess [Eu(tta).sub.3(H.sub.2O).sub.2]. It was recovered by filtration and then dried.

(44) The metallopolymer that was obtained was characterized by steric exclusion chromatography (SEC): M.sub.n=7,039, M.sub.w=10,874, polydispersity index I=1.5.

(45) As for the metallopolymer of Example 5, the differences in value between the Mn and the Mw of the metallopolymer and the conjugated polymer that served in its synthesis confirm that the metal complex was well coordinated within the polymer chains.

Example 7

Thermogravimetric Analysis and DSC of the Conjugated Polymers and Metallopolymers

(46) Thermogravimetric analyses were carried out on the conjugated polymers of Examples 1 to 4, the corresponding metallopolymers (Examples 5 and 6), as well as on the following complexes: tris(2-thenoyltrifluoroacetonato) {3,6-dibromo-9-(4-(2-pyridin-2-yl-benzoimidazol-1-yl)-butyl)-9H-carbazole}europium(III): Eu(tta).sub.3(L) with L for 3,6-dibromo-9-(4-(2-pyridin-2-yl-benzoimidazol-1-yl)-butyl)-9H-carbazole) and tris(2-thenoyltrifluoroacetonato)bis(aquo)europium(III): [Eu(tta).sub.3(H.sub.2O).sub.2].

(47) FIGS. 2 and 3 show a comparison of the ATG curves of the two metal complexes: [Eu(tta).sub.3(H.sub.2O).sub.2], [Eu(tta).sub.3(L)], with those of each of the two metallopolymers of Examples 5 and 6, and those of the conjugated polymers that have served in obtaining the latter.

(48) FIG. 2 shows this comparison for the metallopolymer of Example 5: the loss of mass recorded at around 100° C. on the curve of the [Eu(tta).sub.3(H.sub.2O).sub.2] complex corresponds to the loss of water molecules located in the second coordination sphere of lanthanide. The second loss of mass that is located toward 180° C. can be attributed to the loss of water molecules that are directly linked to metal. The loss of mass recorded at 320° C. that is much more consistent corresponds to the loss of two tta ligands. For the [Eu(tta).sub.3(L)] complex, the loss of mass that is recorded toward 350° C. can also be attributed to the loss of two tta ligands. On the curve of the metallopolymer, it is possible to note two significant losses of mass: a first around 350° C., which is analogous to the one observed for the [Eu(tta).sub.3(L)] complex, and a second at a higher temperature that plays a role in the conjugated polymer by itself and that is linked to the beginning of the break in the alkyl chains of the fluorene units. This comparison therefore makes it possible to demonstrate that the metallopolymer undergoes two losses of mass relative to each of the groups that constitute it: the metal complex and the organic polymer. The ATG curves therefore also confirm that the metal complex was well coordinated within the polymer chains.

(49) FIG. 3 shows this comparison for the metallopolymer of Example 6: The ATG curve of the metallopolymer of Example 6 also shows two quite distinct losses of mass: a first that plays a role toward 350° C., corresponding to the loss of two diketonate ligands, and a second that is higher in temperature that corresponds as in the conjugated polymer to the degradation of alkyl chains grafted on the aromatic units.

(50) Table 3 provides the values of decomposition temperatures (T.sub.d) that are evaluated for each of the compounds shown in FIGS. 2 and 3. They have been measured for a loss of mass of 5%.

(51) TABLE-US-00003 TABLE 3 Characteristic of the Compound T.sub.d (° C.) ± 1° C. [Eu(tta).sub.3(H.sub.2O).sub.2] 162 [Eu(tta).sub.3(L)] 309 Metallopolymer (Example 5) 305 Associated Conjugated Polymer (x = 0.35) 405 Metallopolymer (Example 7) 275 Associated Conjugated Polymer (x = 0.2; 374 y = 0.3)

(52) The values that are presented in Table 1 show that despite the presence of a metal group, the metallopolymers have high decomposition temperatures, a significant parameter for their use in light-emitting diodes.

Example 8

Photophysical Study of Metallopolymers

(53) The emission spectra of the metallopolymers of Examples 5 and 6 in solution have been recorded from solutions produced in the dichloromethane with a mass concentration of 100 μg/ml.

(54) The emission spectrum of the metallopolymer of Example 6 was recorded on thin film that was obtained from a solution produced in chlorobenzene and with a mass concentration of 12 mg/ml deposited by spin-coating. The emitting layer of the light-emitting diode that is produced is deposited under analogous conditions.

(55) FIG. 4 shows the emission spectrum in solution of the metallopolymer of Example 5. It comprises two quite distinct bands, one in the blue range, similar to the one observed with the organic polymer by itself, and one in the red range, characteristic of the emission of europium(III).

(56) FIG. 5 shows the emission spectrum in solution of the metallopolymer of Example 6. It has two different bands, one in the blue range, attributable to the conjugated polymer, and the other in the red range that is characteristic of europium(III), with the band recorded in the red range being the most intense.

(57) FIG. 6 shows the thin-film emission spectrum of the metallopolymer of Example 6.

Example 9

Polymer Light-Emitting Diode (PLED)

(58) A polymer light-emitting diode was produced with the metallopolymer of Example 6. This diode, shown diagrammatically in FIG. 7, successively comprises the following on a glass substrate (S): an indium-tin oxide (ITO) 100 nm anode (A), a PEDOT-PSS 40 nm hole transporting layer (HTL), a metallopolymer 100 nm layer of Example 6 (E), a TPBI 50 nm electron transporting layer (ETL), and a LiF/Al 100 nm cathode (C).

(59) The device with this structure has a red emission color. The light-emitting spectrum is shown in FIG. 8.