Methods for preparing a carbon nanotube conductive ball and a carbon nanotube ball conductive adhesive

Patent metadata

Field	Value
Publication number	US-9816013-B2
Application number	US-201514913370-A
Country	US
Kind code	B2
Filing date	Dec 28, 2015
Priority date	Oct 14, 2015
Publication date	Nov 14, 2017
Grant date	Nov 14, 2017

Abstract

The present disclosure provides a method for preparing a carbon nanotube conductive ball and a method for preparing a carbon nanotube ball conductive adhesive. The method for preparing the carbon nanotube conductive ball integrates the advantages of stability of polymer microsphere and SiO 2 microsphere, and high conductivity of carbon nanotube, by applying polymer microsphere or SiO 2 microsphere as matrix, and plating carbon nanotube material to obtain the spherical carbon nanotube conductive ball. The method is simple, low equipment requirements, abundant raw materials, low cost, and high efficiency, the particle size of the carbon nanotube conductive ball is controllable, the material stability and conductivity of the carbon nanotube conductive ball are excellent. The method for preparing the carbon nanotube ball conductive adhesive adopts carbon nanotube as an electrically conducting particle, which replaces the commonly used conductive gold ball in TFT-LCD field, the disadvantages in traditional conductive adhesive such as high filling content, expensive price, complicated preparation process, environmental pollution, and so on are solved. Besides, the carbon nanotube ball conductive adhesive also has a great prospect in ultra-fine circuit connections.

First claim

What is claimed is:

1. A method for preparing a carbon nanotube conductive ball, comprising the steps of:
step 1, providing carbon nanotube powder and a solvent, adding the carbon nanotube powder into the solvent, extracting a supernatant from the solvent after it is treated by ultrasonication, stirring and centrifugation treatments, so as to obtain a carbon nanotube dispersion liquid with a concentration of 0.01 mg/mL˜10 mg/mL;
step 2, providing a polymer microsphere or a SiO 2 microsphere, adding the polymer microsphere or the SiO 2 microsphere into to the carbon nanotube dispersion liquid, and performing ultrasonication to obtain a uniformly dispersed mixture of carbon nanotube/polymer microsphere, or a mixture of carbon nanotube/SiO 2 microsphere;
step 3, removing the solvent and impurities from the mixture of carbon nanotube/polymer microsphere or the mixture of carbon nanotube/SiO 2 microsphere by performing centrifugation, filtration and drying treatments to obtain a powder of the carbon nanotube conductive ball.

2. The method for preparing a carbon nanotube conductive ball as claimed in claim 1 , wherein in the step 1, the solvent comprises at least one of water, ethanol, ethylene glycol, isopropanol, acetone, chloroform, N-methylpyrrolidone, tetrahydrofuran, dimethylformamide, and toluene.

3. The method for preparing a carbon nanotube conductive ball as claimed in claim 1 , wherein the step 1 further comprises adding a surfactant to the solvent.

4. The method for preparing a carbon nanotube conductive ball as claimed in claim 3 , wherein the surfactant comprises at least one of sodium lauryl sulfate, ammonium lauryl sulfate, sodium dodecyl sulfate, sodium dodecylbenzenesulfonate, and sodium tetradecyl sulfate.

5. The method for preparing a carbon nanotube conductive ball as claimed in claim 1 , wherein in the step 2, the polymer microsphere comprises at least one of polystyrene, polyaniline, polypyrrole, polythiophene, and polyacrylic acid resin microsphere, a size of the polymer microspheres is uniform, a particle size of the polymer microspheres is in a range of 1˜30 μm.

6. A method for preparing a carbon nanotube ball conductive adhesive, comprising the steps of:
step 10, applying the powder of the carbon nanotube conductive ball prepared in claim 1 ;
step 20, providing an epoxy resin, a curing agent, and a promoter, mixing and stirring until they are uniformly dispersed to obtain an epoxy colloid;
step 30, dispersing the powder of the carbon nanotube conductive ball in the epoxy colloid with a mass ratio of 100:1˜50 to obtain a preparatory material of a carbon nanotube ball conductive adhesive;
step 40, degassing the preparatory material of a carbon nanotube ball conductive adhesive to obtain the carbon nanotube ball conductive adhesive.

7. The method for preparing a carbon nanotube ball conductive adhesive as claimed in claim 6 , wherein a mass ratio of each component of the epoxy colloid obtained in the step 20 is: 80%˜95% of the epoxy resin, 1%˜12% of the curing agent, and 0.3%˜5% of the promoter.

8. The method for preparing a carbon nanotube ball conductive adhesive as claimed in claim 6 , wherein in the step 20, the epoxy resin is bisphenol A type epoxy resin E44, bisphenol A type epoxy resin E51, bisphenol A type epoxy resin E54, bisphenol A type epoxy resin EPON826, or bisphenol A type epoxy resin EPON828.

9. The method for preparing a carbon nanotube ball conductive adhesive as claimed in claim 6 , wherein in the step 20, the curing agent is hexahydrophthalic anhydride, tetrahydrophthalic anhydride, succinic acid hydrazide, adipic hydrazide, dicyandiamide or p-phenylenediamine.

10. The method for preparing a carbon nanotube ball conductive adhesive as claimed in claim 6 , wherein in the step 20, the promoter is 2-ethyl-4-methylimidazole, imidazole, dimethyl imidazole, or triethylamine.

11. A method for preparing a carbon nanotube ball conductive adhesive, comprising the steps of:
step 10, applying the powder of the carbon nanotube conductive ball powder prepared in claim 1 ;
step 20, providing an epoxy resin, a curing agent, and a promoter, mixing and stirring until they are uniformly dispersed to obtain an epoxy colloid;
step 30, dispersing the powder of the carbon nanotube conductive ball powder in the epoxy colloid with a mass ratio of 100:1˜50 to obtain a preparatory material of a carbon nanotube ball conductive adhesive;
step 40, degassing the preparatory material of a carbon nanotube ball conductive adhesive to obtain the carbon nanotube ball conductive adhesive;
wherein, a mass ratio of each component of the epoxy colloid obtained in the step 20 is: 80%˜95% of the epoxy resin, 1%˜12% of the curing agent, and 0.3%˜5% of the promoter;
wherein, in the step 20, the epoxy resin is bisphenol A type epoxy resin E44, bisphenol A type epoxy resin E51, bisphenol A type epoxy resin E54, bisphenol A type epoxy resin EPON826, or bisphenol A type epoxy resin EPON828;
wherein, in the step 20, the curing agent is hexahydrophthalic anhydride, tetrahydrophthalic anhydride, succinic acid hydrazide, adipic hydrazide, dicyandiamide or p-phenylenediamine; and
wherein, in the step 20, the promoter is 2-ethyl-4-methylimidazole, imidazole, dimethyl imidazole, or triethylamine.

Assignees

• Shenzhen China Star Optoelect

Inventors

• Zhang Xia
• Lee Yungjui
• Hu Tao

Classifications

• H01B1/18

  the conductive material comprising carbon-silicon compounds, carbon or silicon · CPC title

• C09J9/02 Primary

  Electrically-conducting adhesives · CPC title

• C08K2201/001

  Conductive additives · CPC title

• C01B2202/22

  Electronic properties · CPC title

• C08K3/041

  Carbon nanotubes · CPC title