阅读说明：本技术 一种具有高荧光量子效率的红光聚合物及其制备方法 (Red light polymer with high fluorescence quantum efficiency and preparation method thereof ) 是由 李建辉 于 2020-06-15 设计创作，主要内容包括：本发明属有机发光显示领域,特别涉及一种具有高荧光量子效率的红光聚合物及其制备方法。本发明提供了一种具有高荧光量子效率的红光聚合物,具有式(I)所示结构。本发明还提供了一种具有高荧光量子效率的红光聚合物的制备方法,包括如下步骤：步骤1：氮气保护下,将(4,7-二(5-溴-2-噻吩基)-5,6-二辛氧基苯并噻二唑)和2,7-二溴-2’,3’,6’,7’-四辛基-螺硅双芴进行Suzuki偶联反应得到中间聚合物；步骤2：在中间聚合物中加入2,7-二(4,4,5,5-四甲基-1,3,2-二氧杂硼烷)-9,9-二辛基芴和苯硼酸封端得到式(I)所示聚合物。本发明解决了现有的红光聚合物红色发光纯度不高且荧光量子效率较低的技术问题。(The invention belongs to the field of organic light-emitting display, and particularly relates to a red light polymer with high fluorescence quantum efficiency and a preparation method thereof. The invention provides a red light polymer with high fluorescence quantum efficiency, which has a structure shown in a formula (I). The invention also provides a preparation method of the red light polymer with high fluorescence quantum efficiency, which comprises the following steps: step 1: under the protection of nitrogen, carrying out Suzuki coupling reaction on (4, 7-bis (5-bromo-2-thienyl) -5, 6-dioctyloxybenzothiadiazole) and 2, 7-dibromo-2 ', 3', 6', 7' -tetraoctyl-spirosilabifluorene to obtain an intermediate polymer; step 2: adding 2, 7-bis (4,4,5, 5-tetramethyl-1, 3, 2-dioxaborane) -9, 9-dioctyl fluorene and phenylboronic acid into the intermediate polymer for end capping to obtain the polymer shown in the formula (I). The invention solves the technical problems that the red light emitting purity of the existing red light polymer is not high and the fluorescence quantum efficiency is low.)

1. A red light polymer with high fluorescence quantum efficiency is characterized by having a structure shown in a formula (I):

wherein x is 0.5, and n is 500-.

2. A preparation method of a red light polymer with high fluorescence quantum efficiency is characterized by comprising the following steps:

step 1: under the protection of nitrogen, carrying out Suzuki coupling reaction on (4, 7-bis (5-bromo-2-thienyl) -5, 6-dioctyloxybenzothiadiazole) and 2, 7-dibromo-2 ', 3', 6', 7' -tetraoctyl-spirosilabifluorene to obtain an intermediate polymer;

step 2: adding 2, 7-bis (4,4,5, 5-tetramethyl-1, 3, 2-dioxaborane) -9, 9-dioctyl fluorene and phenylboronic acid into the intermediate polymer for end capping to obtain the polymer shown in the formula (I).

3. The method for preparing a red-emitting polymer with high fluorescence quantum efficiency according to claim 2, wherein the time of the Suzuki coupling reaction in step 1 is 8-48 h.

4. The method for preparing a red-emitting polymer with high fluorescence quantum efficiency according to claim 2, wherein the time of the Suzuki coupling reaction in step 1 is 32 hours.

5. The method for preparing a red-emitting polymer with high fluorescence quantum efficiency according to claim 2, wherein the capping reaction time in step 2 is 6 hours.

6. The method for preparing a red-emitting polymer with high fluorescence quantum efficiency according to claim 2, wherein the temperature of the capping reaction in the step 2 is 90 ℃.

7. The method for preparing a red-light-emitting polymer with high fluorescence quantum efficiency according to claim 2, wherein the amount of the substance of 2, 7-bis (4,4,5, 5-tetramethyl-1, 3, 2-dioxaborane) -9, 9-dioctylfluorene in step 2 is 2 mmol.

Technical Field

The invention belongs to the field of organic light-emitting display, and particularly relates to a red light polymer with high fluorescence quantum efficiency and a preparation method thereof.

Background

PPV polymer light emitting diodes were first introduced in 1990, university of cambridge, england j.h. burroughes et al, pioneering solution-process fabrication of devices, and the possibility of their use as flexible displays was envisioned. The successful development of polymer light emitting diodes has determined the feasibility of this technology, making it desirable to use it as a flat panel display or large area flexible display screen. It is well known that electroluminescent materials emitting high efficiency, high brightness tricolor light are essential for full color development under relatively low voltage driving. However, the red light-emitting polymer is superior to blue and green light in brightness, efficiency, etcIt is a little bit less good. Generally, red-emitting polymers are prepared by doping porphyrins and pyran-containing compounds with europium and iridium complexes or the like in, for example, Alq₃Wide bandgap host materials. However, when the doping concentration is high, these doped red light emitting materials are easily accumulated on the solid thin film, resulting in low fluorescence quantum efficiency of the light emitting device; when the doping concentration is low, the energy transfer cannot be completely from the host material to the red light emitting material, which generally results in a low red light emitting purity of the device.

Therefore, the existing red-doped polymer has low red light-emitting purity and low fluorescence quantum efficiency, which is a technical problem to be solved urgently by those skilled in the art.

Disclosure of Invention

The invention aims to provide a red-light polymer with high fluorescence quantum efficiency.

It is another object of the present invention to provide a method for preparing the above red-emitting polymer having high fluorescence quantum efficiency.

The above purpose of the invention is realized by the following technical scheme:

the invention provides a red light polymer with high fluorescence quantum efficiency, which has a structure shown in a formula (I):

wherein x is 0.5, and n is 500-.

The invention also provides a preparation method of the red light polymer with high fluorescence quantum efficiency, which comprises the following steps:

step 1: under the protection of nitrogen, carrying out Suzuki coupling reaction on (4, 7-bis (5-bromo-2-thienyl) -5, 6-dioctyloxybenzothiadiazole) and 2, 7-dibromo-2 ', 3', 6', 7' -tetraoctyl-spirosilabifluorene to obtain an intermediate polymer;

step 2: adding 2, 7-bis (4,4,5, 5-tetramethyl-1, 3, 2-dioxaborane) -9, 9-dioctyl fluorene and phenylboronic acid into the intermediate polymer for end capping to obtain the polymer shown in the formula (I).

Preferably, the time of the Suzuki coupling reaction in the step 1 is 8-48 h.

Preferably, the time of the Suzuki coupling reaction in step 1 is 32 h.

Preferably, the capping reaction time in step 2 is 6 h.

Preferably, the temperature of the capping reaction in step 2 is 90 ℃.

Preferably, the amount of the substance of 2, 7-bis (4,4,5, 5-tetramethyl-1, 3, 2-dioxaborane) -9, 9-dioctylfluorene in step 2 is 2 mmol.

Compared with the prior art, the invention has the following advantages and beneficial effects:

the photoluminescence spectrum of the toluene solution of the polymer prepared by the embodiment of the invention has an obvious red light emission peak around 620nm, which indicates that the red light with higher luminous purity is prepared by the invention. And the film fluorescence spectrum of the polymer always shows unimodal emission, which shows that the intramolecular energy transfer is relatively complete, and the intermolecular aggregation effect is not continuously enhanced along with the increase of the polymerization degree. The red light polymer with high fluorescence quantum efficiency prepared by the invention has good fluorescence quantum efficiency, and the highest fluorescence quantum efficiency reaches 99.01%.

Drawings

Fig. 1 is a photoluminescence spectrum of a red-emitting polymer with high fluorescence quantum efficiency prepared in an example of the present invention in a thin film state.

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.