Carbon fiber manufacturing method

Abstract

A carbon fiber manufacturing method is provided. A carbon fiber precursor fiber bundle is performed with a high-temperature carbonization step to form a carbon fiber, and then the carbon fiber is performed with a plasma surface treatment so that the surface of the carbon fiber is formed with a plasma-modified configuration which is relatively rougher. Finally, the surface of the carbon fiber is coated with a resin oiling agent to obtain the carbon fiber having the resin oiling agent thereon. Particularly, through a plasma surface treatment step, the surface of the carbon fiber is roughened and provided with functional groups, which is beneficial to enhance the interface bonding of the resin oiling agent and the carbon fiber. The structure of the carbon fiber is more stable and reliable. The cost of the carbon fiber production equipment and the working time can be reduced effectively.

Description

FIELD OF THE INVENTION[0001]The present invention relates to a carbon fiber manufacturing technique, and more particularly to a carbon fiber manufacturing method which can greatly improve the sizing quality of a carbon fiber and effectively reduce the cost of the carbon fiber production equipment and the working time.BACKGROUND OF THE INVENTION[0002]Carbon fibers are classified into carbon fibers or graphite fibers according to their carbon contents, which have excellent mechanical properties and electrical properties and can be widely used in various applications. A conventional carbon fiber is achieved by bundling precursor fibers, such as polyacrylonitrile fibers, to form a carbon fiber precursor fiber bundle, and then the carbon fiber precursor fiber bundle is calcined (high-temperature carbonization) to form the carbon fiber.[0003]There are various precursor fibers of carbon fibers on the market, such as rayon, poly vinyl alcohol, vinylidene chloride, polyacrylonitrile (PAN), p...

AI Technical Summary

Benefits of technology

[0029]Specifically, through plasma surface treatment, the surface of the carbon fiber can be roughened and provided with the functional groups, which is beneficial to enhance the interface bonding of the resin oiling agent and the carbon fiber in the subsequent sizing step. The structure of the carbon fiber is more stable and reliable. By the microwave focusing heating way, the same apparatus can be applied to a carbon fiber precursor fiber bundle whose surface has not been processed with a pre-oxidation treatment or a carbon fiber precursor fiber bundle whose surface has been processed with a pre-oxidation treatment in advance. By simply adjusting the microwave power, the apparatus can be used to produce general carbon fibers or high modulus carbon fibers (graphite fibers) so as reduce the cost of the carbon fiber production equipment and the working time effectively.

Problems solved by technology

Since these impurities are present between the surface of the carbon fiber and the resin oiling agent, the adhesion between the carbon fiber and the resin oiling agent is insufficient, and the purpose of protecting the fiber cannot be achieved

Furthermore, in the high-temperature carbonization step, the surface of the carbon fiber is excessively finely formed due to high-temperature sintering, and there are few functional groups on the surface.

As a result, the fiber and the resin oiling agent cannot be bonded fully in the sizing step.

A relatively long period of time is required.

Besides, the heat treatment is always performed with a large number of fibers at a time, so it is difficult to control the processing quality.

This also takes more time.

Moreover, a change of the electrolyte may affect the processing quality.

Images