Polymer of poly(arylene ether)s, manufacturing method thereof and polymer light emitting diode with organic light emitting layer made from the same

Abstract

A polymer of poly(arylene ether)s, a manufacturing method thereof, and a polymer light emitting diode with an organic light emitting layer made from the polymer are provided. The polymer is formed by processing a nucleophilic polycondensation between a fluoro-containing monomer having an electron-withdrawing group and a multi-phenyl monomer. The polymer has a host portion with fluoro- or trifluoromethyl substituents, and a customer portion with multi-phenyl groups.

Claims

1. A polymer of poly(arylene ether)s, having a molecular structure given in the following formula (1): ##STR00046## wherein Ar is selected from the group consisting of ##STR00047## ##STR00048## ##STR00049## ##STR00050## Y is selected from the group consisting of ##STR00051## ##STR00052## ##STR00053## and n is an integer greater than or equal to 2.

2. The polymer of poly(arylene ether)s according to claim 1, wherein the polymer of poly(arylene ether)s is ##STR00054## or ##STR00055##

3. The polymer of poly(arylene ether)s according to claim 1, wherein the polymer of poly(arylene ether)s is coated to form a thin film used as an organic light emitting layer, and applied to a polymer light emitting diode.

4. A polymer light emitting diode, comprising an organic light emitting layer made from the polymer of poly(arylene ether)s according to claim 1.

Description

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(1) The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments. Furthermore, if there is no specific description in the invention, singular terms such as a, one, and the include the plural number. For example, a compound or at least one compound may include a plurality of compounds, and the mixtures thereof. If there is no specific description in the invention, % means weight percentage (wt %), and the numerical range (e.g. 10%11% of A) contains the upper and lower limit (i.e. 10%A11%). If the lower limit is not defined in the range (e.g. less than, or below 0.2% of B), it means that the lower limit is 0 (i.e. 0%B0.2%). The proportion of weight percent of each component can be replaced by the proportion of weight portion thereof. The abovementioned terms are used to describe and understand the present invention, but the present invention is not limited thereto.

(2) The present invention provides a polymer of poly(arylene ether)s and a method of manufacturing the same. The polymer of poly(arylene ether)s is suitable for use as a functional polymer film, and in particular for use as an organic light emitting layer in a polymer light emitting diode.

(3) In one embodiment of the present invention, the polymer of poly(arylene ether)s has the molecular formula given in the following formula

(4) ##STR00022##
wherein Ar is

(5) ##STR00023## ##STR00024## ##STR00025## ##STR00026## ##STR00027## ##STR00028## ##STR00029##
and n is an integer greater than or equal to 2. The polymer of poly(arylene ether)s mainly includes a subject portion and an object portion, the subject portion is connected with the object portion by an ether bond. Preferably, the polymer of poly(arylene ether)s is

(6) ##STR00030##
or

(7) ##STR00031##
which includes the subject portion derived from pyrene with fluorine-containing substituents, and the object portion derived from fluorene, and they are connected through the ether bonds. The polymer of poly(arylene ether)s can be coated to form an thin film used as an organic light emitting layer, and applied to a polymer light emitting diode.

(8) Another embodiment of the present invention provides a manufacturing method of the polymer of poly(arylene ether)s, comprising steps of (S01) providing a fluorine-containing monomer; (S02) providing a multi-phenyl monomer; and (S03) processing a nucleophilic polycondensation between the fluorine-containing monomer and the multi-phenyl monomer to form a polymer of poly(arylene ether)s. The principle and the implementation details of each step in this embodiment of the present invention will be described in detail hereinafter.

(9) First, the manufacturing method of the polymer of poly(arylene ether)s according to one embodiment of the present invention is the step (S01): providing a fluorine-containing monomer. In this step, the fluorine-containing monomer can be provided with a molecular structure given in the following formula (I):
D1-Ar-D1(I),
wherein Ar is

(10) ##STR00032## ##STR00033## ##STR00034## ##STR00035##
D1 is halogen or hydroxyl group, wherein each Ar contains two bonding terminals to respectively connect with the D1, thereby forming D1-Ar-D1 structured fluorine-containing monomer (formula (I)). Every bonding terminal of Ar described hereinafter does not represent alkyl groups, but indicates a position for bonding the halogen or the hydroxyl group.

(11) Furthermore, in this step, the fluorine-containing monomer can be prepared by the following steps, for example: preparing a mixing solvent of 50 mL Toluene and 50 mL tetrahydrofuran (THF) in a flask, which is purged with nitrogen gas for 20 minutes and heated to 110 C. in a sand bath; dissolving 2.30 g (8.8 mmol) 4-Bromo-2,6-difluorobenzotrifluoride and 2.4 g (9.72 mmol) Pyren-1-yl boronic acid fully in the mixing solvent to form an yellow solution; preparing 2.0 M K.sub.2CO.sub.3 aqueous which is purged with nitrogen gas and then added into the flask to mix by stirring for about 5 minutes; adding a small amount of catalyst of Tetrakis (triphenylphosphine) palladium (Pd(PPh.sub.3).sub.4) and introducing nitrogen gas by a needle tube after installing a condenser with the flask; heating and mixing by stirring for 24 hours; turning off the heat source but keeping stirring to cool the solution down to room temperature; taking out the organic layer of the solution and removing the solvent by using a rotary evaporator; extracting with deionized water and chloroform (CHCl.sub.3) to obtain an organic layer; after the organic layer is filtered by using anhydrous MgSO.sub.4, the organic layer is concentrated by using the rotary evaporator; and processing a column chromatography to obtain an intermediate product 1:

(12) ##STR00036##
having green/gray white color and 80% yield.

(13) Next, the manufacturing method of the polymer of poly(arylene ether)s according to one embodiment of the present invention is the step (S02): providing a multi-phenyl monomer having a molecular structure given in the following formula (II):

(14) ##STR00037##
wherein Y is

(15) ##STR00038## ##STR00039## ##STR00040##
and D2 is halogen or hydroxyl group; wherein D2 is the hydroxyl group if D1 is the halogen group, or D2 is the halogen group if D1 is the hydroxyl group. Preferably, D2 can be fluoro (F) or chloro (Cl), but it is not limited thereto. In addition, each Y molecule includes two bonding terminals to respectively connect with the D2, thereby forming D2-Y-D2 structured multi-phenyl monomer (formula (II)). Every bonding terminal of Y described hereinafter does not represent alkyl groups, but indicates a position for bonding the halogen or the hydroxyl group. Regarding the last second to thirteen options of Y, the bending C2-C8 carbon chains extended from nitrogen (N) or oxygen (O) are not considered as the bonding terminals .

(16) In this step, the multi-phenyl monomer can be prepared by the following steps, for example: preparing a mixing solvent of 90 ml. Toluene and 20 mL ethanol in a flask, which is purged with nitrogen gas for 20 minutes and heated to 110 C. in a sand bath; fully dissolving 2.2 g (4.6 mmol) 2,7-Dibromo-9,9-spirobifluorene and 1.5 g (10.0 mmol) 4-methoxyphenyl boronic acid in the mixing solvent to form an yellow solution; preparing 2.0 M K.sub.2CO.sub.3 aqueous which is purged with nitrogen gas and then added into the flask to mix by stirring for about 5 minutes; adding a small amount of catalyst of Pd(PPh.sub.3).sub.4 and introducing nitrogen gas by a needle tube after installing a condenser with the flask; heating and mixing by stirring for 24 hours; turning off the heat source but keeping stirring to cool the solution down to room temperature; taking out the organic layer of the solution and removing the solvent by using a rotary evaporator; extracting with deionized water and chloroform (CHCl.sub.3) to obtain an organic layer; after the organic layer is filtered by using anhydrous MgSO.sub.4, the organic layer is concentrated by using the rotary evaporator and recrystallized for several times; processing a column chromatography to obtain an intermediate product 2:

(17) ##STR00041##
having 85% yield; dissolving the intermediate product 2 in 50 mL dichloromethane (CH.sub.2Cl.sub.2) and adding 3 equivalent of boron tribromide (BBr.sub.3) at 78 C. in an ice bath; after stirring for 1 hour, raising temperature slowly to room temperature; keeping stirring for 24 hours; after extracting directly with deionized water several times and filtering by using anhydrous MgSO.sub.4, the organic layer is concentrated by using the rotary evaporator and recrystallized for several times to obtain an intermediate product 3:

(18) ##STR00042##
having 75% yield, wherein the above-mentioned boron tribromide (BBr.sub.3) may be replaced by boron trifluoride (BF.sub.3) or boron trichloride (BCl.sub.3).

(19) In addition, it should be noted that the steps (S01) and (S02) of the present invention may be interchanged or carried out simultaneously.

(20) Next, the manufacturing method of the polymer of poly(arylene ether)s according to one embodiment of the present invention is the step (S03): processing a nucleophilic polycondensation between the fluorine-containing monomer and the multi-phenyl monomer to form a polymer of poly(arylene ether)s. In this step, for example, 175 g of the intermediate product 3, 1.34 g of the intermediate 1, and 1.21 g K.sub.2CO.sub.3 are placed in a 50 mL of three-nacked flask, then 17 mL toluene and 27 mL N,N-Dimethylacetamide (DMAc) are added sequentially. The temperature is raised to 160 C. for carrying out the reaction for 24 hours. After that, cooling to room temperature and precipitating by using 3050 mL THF to obtain a final product. The final product is washed with deionized water and methanol several times to obtain the polymer of poly(arylene ether)s 4:

(21) ##STR00043##
(Mw: 226500; Mn: 127000; PDI: 1.75).

(22) Furthermore, depending on the requirements, the above-mentioned polymer of poly(arylene ether)s according to the present invention may be produced into a suitable form for standby, for example, after the step (S03), a step (S04) is further included for dissolving the polymer of poly(arylene ether)s in an organic solvent, such as chlorobenzene, o-dichlorobenzene, tetrahydrofuran, chloroform, or dimethylacetamide; and coating the polymer on a surface then forming a thin film after drying, for example, the thin film can serve as an organic light emitting layer and be applied to a polymer light emitting diode, but it is not limited thereto.

(23) To verify the structural stability and electro-optical characteristics of the polymer of poly(arylene ether)s, the polymer of poly(arylene ether)s 4 is subject to a thermal property analysis; and a small-molecule light emitting material TPSBF (2,2,7,7-tetra-(pyrene-1-yl)-9,9-spirobifluorene,

(24) ##STR00044##
and PFO (Poly(9,9-dioctylfluorene),

(25) ##STR00045##
which is derived from a common blue light polymer material PDAFs (poly (9,9-dialkylfluorene)s) are used as the comparative examples to perform the electro-optical analysis.

(26) First, the polymer of poly(arylene ether)s 4 is analyzed by using a Thermogravimetric analyzer (TGA). Under a nitrogen atmosphere, the standard pyrolysis temperature is determined by a temperature Td5% that the weight loss reaches 5% of the original weight. The material is pre-baked at 120 C. in nitrogen for 20 minutes to remove water attached thereon then cooled down to 50 C., and heated to 800 C. at a rate of 10 C./min. The pyrolysis temperature of the material is observed thereafter. After analysis, Td5% of the polymer of poly(arylene ether)s 4 is obtained, which is up to 592 C.

(27) The electro-optical characteristics of the materials are shown in Table 1.

(28) TABLE-US-00001 TABLE 1 HOMO/ UV-vis Photoluminescence LUMO Eg (nm) (nm) (eV) (eV) CIE polymer of 342 408 5.9/2.6 3.3 (0.16, poly(arylene 0.03) ether)s4 TPSBF 358 421 5.7/2.6 3.1 (0.15, 0.04) PFO 376 426 5.8/2.8 3.0 (0.15, 0.14)

(29) From Table 1, the polymer of poly(arylene ether)s 4 has a blue light coordinate approximate to TPSBF, and the light color and energy gap both comply with the standard of deep blue light material. In addition, compared with TPSBF and PFO, the polymer of poly(arylene ether)s 4 has a highest energy gap of about 3.3 eV.

(30) Compared with the current technology, the polymer of poly(arylene ether)s has a subject portion at one side with eletron-withdrawing fluorine-containing substituents, and an object portion at another side with multi-phenyl group, which is connected with each other by an ether bond formed through a nucleophilic polycondensation, and the fluorine-containing substituents can improve the solubility in water and polymerization degree. Furthermore, the polymer of poly(arylene ether)s can be used to form a good blue light emitting material which has a flexibility like polymers and deep blue light emitting properties like small molecules. It maintains high energy gap and very available to the polymer light emitting diode.

(31) The present invention has been described with preferred embodiments thereof and it is understood that many changes and modifications to the described embodiments can be carried out without departing from the scope and the spirit of the invention that is intended to be limited only by the appended claims.