阅读说明：本技术 一种基于噻唑的有机电致发光材料及其制备方法 (Thiazole-based organic electroluminescent material and preparation method thereof ) 是由 胡金超 于 2020-06-15 设计创作，主要内容包括：本发明属光电显示器件技术领域,具体涉及一种基于噻唑的有机电致发光材料及其制备方法。本发明提供了一种基于噻唑的有机电致发光材料,其结构如式(I)所示。本发明还提供了一种基于噻唑的有机电致发光材料的制备方法,将式(II)所示化合物,3,10-二溴-14-(3-(5-苯基-1,3,4-恶二唑-2-基)苯基)-14H--双(S,S-二氧-二苯并噻吩)并吡咯和2-(3-(3,10-双(4,4,5,5-四甲基-1,3,2-二氧杂硼烷-2-基)-14H-双(S,S-二氧-二苯并噻吩)并吡咯-5-苯基-1,3,4-恶二唑通过Suzuki偶联反应制得式(I)所示聚合物。本发明解决了现有的有机电致发光材料难以兼顾空穴和电子传输效率,且电致发光效率较差的技术问题。(The invention belongs to the technical field of photoelectric display devices, and particularly relates to a thiazole-based organic electroluminescent material and a preparation method thereof. The invention provides a thiazole-based organic electroluminescent material, which has a structure shown in a formula (I). The invention also provides a preparation method of the thiazole-based organic electroluminescent material, which is characterized in that a compound shown as a formula (II), 3, 10-dibromo-14- (3- (5-phenyl-1, 3, 4-oxadiazole-2-yl) phenyl) -14H-bis (S, S-dioxo-dibenzothiophene) pyrrole and 2- (3- (3, 10-bis (4,4,5, 5-tetramethyl-1, 3, 2-dioxaborane-2-yl) -14H-bis (S, S-dioxo-dibenzothiophene) pyrrole-5-phenyl-1, 3, 4-oxadiazole are subjected to Suzuki coupling reaction to prepare the polymer shown as the formula (I), and the invention solves the problems that the existing organic electroluminescent material is difficult to realize both hole transmission efficiency and electron transmission efficiency, and poor electroluminescent efficiency.)

1. A thiazole-based organic electroluminescent material is characterized in that the structure is shown as formula (I):

wherein n is 200-.

2. A preparation method of a thiazole-based organic electroluminescent material is characterized in that a compound shown as a formula (II), 3, 10-dibromo-14- (3- (5-phenyl-1, 3, 4-oxadiazole-2-yl) phenyl) -14H-bis (S, S-dioxo-dibenzothiophene) pyrrole and 2- (3, 10-bis (4,4,5, 5-tetramethyl-1, 3, 2-dioxaborane-2-yl) -14H-bis (S, S-dioxo-dibenzothiophene) pyrrole-5-phenyl-1, 3, 4-oxadiazole are subjected to Suzuki coupling reaction to prepare a polymer shown as a formula (I)

3. A preparation method of thiazole-based organic electroluminescent material according to claim 2, wherein the time of the Suzuki coupling reaction is 24h-48 h.

4. A preparation method of thiazole-based organic electroluminescent material according to claim 2, wherein the temperature of the Suzuki coupling reaction is 85 ℃.

5. A preparation method of thiazole-based organic electroluminescent material according to claim 2, characterized in that said compound of formula (II) is prepared by the following steps:

step 1: stirring 2-aminobenzaldehyde and 50mL of acetone in an ice bath for 30min, then dropwise adding 6% sodium hydroxide solution (120mL) into the system, removing the ice bath after dropwise adding, and stirring at normal temperature for 12h to obtain the compound shown in the formula (III)

Step 2: carrying out substitution reaction on 4, 7-dibromo-2, 1, 3-benzothiadiazole and a compound shown as a formula (III) to prepare a compound shown as a formula (IV)

And step 3: and (3) carrying out bromination reaction on the compound shown in the formula (IV) to obtain the compound shown in the formula (II).

Technical Field

The invention belongs to the technical field of photoelectric display devices, and particularly relates to a thiazole-based organic electroluminescent material and a preparation method thereof.

Background

The 21 st century is called as a brand-new electronic information age, the demand of people for information is increasing due to the development of networks, and smart phones, watches and (tablet) computers become an essential part of people's lives. The development of display technology is greatly promoted by the arrival of the information age, and the pursuit of lighter, thinner and energy-saving large-size and flexible displays makes organic electroluminescence become the mainstream of the market. The organic light-emitting diode has the advantages of low voltage drive, self luminescence of pixel points, quick response, wide viewing angle, thin thickness and the like, and is solid full-color display which can be processed by a flexible substrate and covers the whole visible spectrum. In the aspect of processing technology, an ink-jet printing or spin coating process can be selected to manufacture a large-area panel, so that the production cost is greatly reduced, and the manufacturing method becomes a hot spot in the field of display technology research make internal disorder or usurp.

The hole transport material and the electron transport material in the organic electroluminescent material usually adopt unipolar micromolecules, and although the hole/electron transport type micromolecule main body material structure contains electron-donating or electron-withdrawing groups, the hole and electron transport property is good, a hole or electron blocking layer is usually required to be added into the device, the driving voltage is high, and the electroluminescent efficiency is poor.

Therefore, the conventional organic electroluminescent material is difficult to achieve both hole and electron transport efficiency, and the poor electroluminescent efficiency is a technical problem to be solved urgently by those skilled in the art.

Disclosure of Invention

The invention provides a thiazole-based organic electroluminescent material and a preparation method thereof, and solves the technical problems that the existing organic electroluminescent material is difficult to give consideration to both hole and electron transmission efficiency and the electroluminescent efficiency is poor.

The invention provides a thiazole-based organic electroluminescent material, which has a structure shown in a formula (I):

wherein n is 200-.

The invention also provides a preparation method of the thiazole-based organic electroluminescent material, which is characterized in that a compound shown as a formula (II), 3, 10-dibromo-14- (3- (5-phenyl-1, 3, 4-oxadiazole-2-yl) phenyl) -14H-bis (S, S-dioxo-dibenzothiophene) pyrrole and 2- (3- (3, 10-bis (4,4,5, 5-tetramethyl-1, 3, 2-dioxaborane-2-yl) -14H-bis (S, S-dioxo-dibenzothiophene) pyrrole-5-phenyl-1, 3, 4-oxadiazole are subjected to Suzuki coupling reaction to prepare a polymer shown as a formula (I)

Preferably, the time of the Suzuki coupling reaction is 24-48 h.

Preferably, the temperature of the Suzuki coupling reaction is 85 ℃.

Preferably, the compound represented by the formula (II) is prepared by the following steps:

step 1: stirring 2-aminobenzaldehyde and 50mL of acetone in an ice bath for 30min, then dropwise adding 6% sodium hydroxide solution (120mL) into the system, removing the ice bath after dropwise adding, and stirring at normal temperature for 12h to obtain the compound shown in the formula (III)

Step 2: carrying out substitution reaction on 4, 7-dibromo-2, 1, 3-benzothiadiazole and a compound shown as a formula (III) to prepare a compound shown as a formula (IV)

And step 3: and (3) carrying out bromination reaction on the compound shown in the formula (IV) to obtain the compound shown in the formula (II).

The invention has the following beneficial effects:

the HOMO energy level of the polymer prepared by the invention is in the range of-5.67-5.76 eV, and the LUMO energy level is in the range of-2.12-2.33 eV. When the polymerization degree is increased, the oxidation potential of the polymer is obviously reduced, and the HOMO energy level is increased; the reduction potential is obviously increased, the LUMO energy level is reduced, the electrical band gap is narrowed, and the electroluminescent efficiency of the polymer is effectively improved. The main emission peak of the polymer prepared by the invention is about 450nm, and the spectrum is slightly broadened along with the increase of the polymerization degree. The CIE (x + y) value is within 0.3-0.4.

In addition, the polymer prepared by the invention has reduced starting voltage and increased current density and brightness along with the increase of polymerization degree, and shows that more carriers are compounded in a light-emitting layer because the injection and the transmission of the carriers are relatively balanced due to the introduction of thiazole units and SO units.

Drawings

FIG. 1 is an electrochemical plot of polymers prepared in examples 6-10 of the present invention;

FIG. 2 is a graph of the electroluminescence spectra (EL) of polymers obtained in examples 6 to 10 of the present invention;

FIG. 3 is a graph of current density-luminance-voltage curves for polymers prepared in examples 6-10 of the present invention;

FIG. 4 is a graph of current density versus current efficiency for polymers prepared in examples 6-10 of the present invention.

Detailed Description

The present invention will be described in further detail with reference to specific examples, which are not intended to limit the present invention in any manner. Reagents, methods and apparatus used in the present invention are conventional in the art unless otherwise indicated.