Unlock instant, AI-driven research and patent intelligence for your innovation.

Carbazole-fluorene copolymer blue-light materials with spatial structure

A blue-light material and spatial structure technology, applied in the field of functional materials, can solve problems that affect the saturation color purity of the emitted light, the stability of the luminous color, the reduction of luminous efficiency, and the difficulty of electron injection.

Inactive Publication Date: 2012-12-19
NANJING UNIV
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Although polyfluorene has unique advantages as a light-emitting material, it also has the following disadvantages: (1) The LUMO and HOMO of polyfluorene do not match the work functions of the anode and cathode of OLED, which makes the injection of holes and electrons difficult and ineffective. balance, so that the starting voltage is higher and the luminous efficiency is reduced; (2) polyfluorene is easy to form aggregated state or excimer association, so that the thermal stability of the spectrum is deteriorated, and there will be a red shift peak, which affects the light emission of the device. Saturated color purity and stability of luminous color, but also reduces luminous efficiency
[0005] The above reaction belongs to the Suziki polymerization reaction, the synthesized molecular structure is linear or branched, and fluorene is conjugated with carbazole. One unfavorable factor is: due to the electron-rich characteristics of carbazole, the polyfluorene molecular chain can be effectively improved in carbazole. At the same time, it also affects the conduction properties of the fluorene chain

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Carbazole-fluorene copolymer blue-light materials with spatial structure
  • Carbazole-fluorene copolymer blue-light materials with spatial structure
  • Carbazole-fluorene copolymer blue-light materials with spatial structure

Examples

Experimental program
Comparison scheme
Effect test

example 1

[0015] Monomer a is a 9-ethylcarbazole-substituted fluorene oligomer containing fluorenol. Under the catalytic reaction of p-toluenesulfonic acid, the monomer a is dehydrated and polycondensed into a ring oligomer in 1% trimethylbenzene solution. Separation by chromatographic column (eluent is dichloromethane and petroleum ether), the product is light yellow powder solid, the yield is 35%. The main physical properties of the polymer: the number average molecular weight is 4538, the polymerization dispersion is 1.05, there is no obvious glass transition temperature, the 5% thermal decomposition temperature is 405°C, and the maximum photoinduced blue light wavelength is 406cm -1 and 422cm -1 , relative to the luminous efficiency of 9,10-diphenylanthracene in cyclohexane of 0.9, the photoluminescence efficiency of the polymer blue light material of the present invention is 0.85. The polymer synthesis process is shown in chemical reaction formula 3.

[0016]

example 2

[0017] Example 2: Monomer a is a 9-methylphenylcarbazole-substituted fluorene oligomer containing fluorenol. Under the catalyzed reaction of methanesulfonic acid, the monomer a is dehydrated and polycondensed into a cyclic polymer in 1% trimethylbenzene solution, see chemical reaction formula 4. Separation by chromatographic column (eluent is dichloromethane and petroleum ether), the product is a white powdery solid, and the yield is 40%. Main physical properties of the polymer: number average molecular weight 4803, polymerization dispersion 1.03, no obvious glass transition temperature, 5% thermal decomposition temperature 395°C, maximum photoinduced blue light wavelength 407cm -1 and 421cm -1 , relative to the luminous efficiency of 9,10-diphenylanthracene in cyclohexane of 0.9, the photoluminescence efficiency of the invented blue light material is 0.80.

[0018]

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
energyaaaaaaaaaa
thermal decomposition temperatureaaaaaaaaaa
thermal decomposition temperatureaaaaaaaaaa
Login to View More

Abstract

The invention discloses carbazole-fluorene copolymer blue-light materials with a spatial structure. The general molecular structural formula of the polymers is the molecular formula 4 in the description; the number-average molecular weight of the polymers is 3,000 to 8,000; the polymerization dispersion is 1.01 to 1.1; seen from appearance, the polymers are white or yellowish powder solid; 5 percent thermolysis temperature is 300 to 450 DEG C; in the ultraviolet irradiation, the polymers turn blue; and the photoluminescence efficiency of the copolymer blue-light materials is 0.7 to 0.9, whilethe luminous efficiency of 9,10-diphenylanthrancene in cyclohexane is 0.9.

Description

technical field [0001] The invention belongs to the field of functional materials. Using the electrophilic substitution reaction of heterocycles, a carbazole-fluorene copolymerized blue light material with spatial structure was prepared. Background technique [0002] Organic electroluminescent materials are one of the research hotspots in the field of optoelectronic information functional materials. Among them, polyfluorene has high photothermal stability, and the fluorescence quantum efficiency of solid fluorene is as high as 60% to 80%, and the band gap energy is greater than 2.90eV. It has become the most important blue light material and is the new generation of flat panel display technology. One of the core components and white light primary color materials [1] . Although polyfluorene has unique advantages as a light-emitting material, it also has the following disadvantages: (1) The LUMO and HOMO of polyfluorene do not match the work functions of the anode and catho...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): C08G61/12
Inventor 全一武周宇卢煜陈庆民
Owner NANJING UNIV