CARBON FIBER SURFACE OILING AGENT CHANGING METOD

Abstract

A carbon fiber surface oiling agent changing method includes providing a raw material step; performing a desizing step; performing a plasma surface treatment step; and performing a sizing step. In the plasma surface treatment step, the impurities that originally adhere to the surface of the carbon fiber can be broken to form small molecules and blown away through the physical and chemical reaction of the plasma gas flow, enabling the surface of the carbon fiber to be roughened and provided with functional groups, which is beneficial to achieve high-quality interface bonding of the carbon fiber and the matrix resin in the subsequent sizing step, thereby enhancing the characteristics of carbon fiber composite materials.

Claims

1. A carbon fiber surface oiling agent changing method, comprising: providing a raw material step, providing a carbon fiber, the carbon fiber being coated with a first oiling agent; performing a desizing step, the first oiling agent being removed; performing a plasma surface treatment step, providing a plasma gas flow to act on the carbon fiber; and performing a sizing step, a second oiling agent being coated on the carbon fiber.

2. The carbon fiber surface oiling agent changing method as claimed in claim 1, wherein in the plasma surface treatment step, the plasma gas flow with a power of 100-10000 watts acts on the carbon fiber for 10-1000 milliseconds.

3. The carbon fiber surface oiling agent changing method as claimed in claim 1, wherein in the plasma surface treatment step, an atmospheric plasma gas flow with a power of 100-10000 watts acts on the carbon fiber for 10-1000 milliseconds.

4. The carbon fiber surface oiling agent changing method as claimed in claim 1, wherein in the plasma surface treatment step, a low-pressure plasma gas flow with a power of 100-10000 watts acts on the carbon fiber for 10-1000 milliseconds.

5. The carbon fiber surface oiling agent changing method as claimed in claim 1, wherein in the plasma surface treatment step, a microwave plasma gas flow with a power of 100-10000 watts acts on the carbon fiber for 10-1000 milliseconds.

6. The carbon fiber surface oiling agent changing method as claimed in claim 1, wherein in the plasma surface treatment step, a glow plasma gas flow with a power of 100-10000 watts acts on the carbon fiber for 10-1000 milliseconds.

7. The carbon fiber surface oiling agent changing method as claimed in claim 1, wherein the desizing step is performed at a temperature of 250-650 C. for 1-60 seconds.

8. The carbon fiber surface oiling agent changing method as claimed in claim 1, wherein the desizing step is performed by providing an organic solvent to remove the first oiling agent.

9. The carbon fiber surface oiling agent changing method as claimed in claim 8, wherein the organic solvent is acetone or chloroform.

10. The carbon fiber surface oiling agent changing method as claimed in claim 1, wherein in the sizing step, the second oiling agent is coated on the carbon fiber by soaking.

11. The carbon fiber surface oiling agent changing method as claimed in claim 1, wherein in the sizing step, the second oiling agent is coated on the carbon fiber by immersing.

12. The carbon fiber surface oiling agent changing method as claimed in claim 1, wherein the first oiling agent is a thermosetting resin oiling agent.

13. The carbon fiber surface oiling agent changing method as claimed in claim 1, wherein the second oiling agent is a thermosetting resin oiling agent.

14. The carbon fiber surface oiling agent changing method as claimed in claim 1, wherein the second oiling agent is a thermoplastic resin oiling agent.

15. The carbon fiber surface oiling agent changing method as claimed in claim 1, wherein the second oiling agent is one of polyurethane (PU), polyethene (PE), polypropylene (PP), and acrylic.

16. The carbon fiber surface oiling agent changing method as claimed in claim 1, further comprising a drying step after the sizing step, enabling the second oiling agent to be firmly adhered to the carbon fiber.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0026] FIG. 1 is a flow diagram of a carbon fiber surface oiling agent changing method in accordance with a first embodiment of the present invention;

[0027] FIG. 2 is a sectional schematic view of a carbon fiber raw material in the step of providing a raw material in accordance with the carbon fiber surface oiling agent changing method the present invention;

[0028] FIG. 3 is a sectional schematic view of a carbon fiber after finishing a desizing step in accordance with the carbon fiber surface oiling agent changing method the present invention;

[0029] FIG. 4 is a sectional schematic view of a carbon fiber after finishing a plasma surface treatment step in accordance with the carbon fiber surface oiling agent changing method the present invention;

[0030] FIG. 5 is a sectional schematic view of a carbon fiber after finishing a sizing step in accordance with the carbon fiber surface oiling agent changing method the present invention; and

[0031] FIG. 6 is a flow diagram of a carbon fiber surface oiling agent changing method in accordance with a second embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings.

[0033] The present invention discloses a carbon fiber surface oiling agent changing method which is capable of effectively changing the oiling agent on the surface of a carbon fiber. As shown in FIG. 1, the carbon fiber surface oiling agent changing method of the present invention comprises providing a raw material step, performing a desizing step, performing a plasma surface treatment step, and performing a sizing step.

[0034] As shown in FIG. 1 to FIG. 5, the step of providing the raw material is to provide a carbon fiber raw material 10 formed of a carbon fiber 11 whose surface is coated with a first oiling agent 12. The carbon fiber 11 may be made of a carbon fiber precursor fiber bundle formed by bundling precursor fibers, such as rayon, poly vinyl alcohol, vinylidene chloride, polyacrylonitrile (PAN), pitch, and the like, obtained by calcination. In practice, the first oiling agent 12 may be a thermosetting resin oiling agent.

[0035] In the desizing step, the first oiling agent 12 is removed from the surface of the carbon fiber raw material 10. In practice, the desizing step may be performed at a temperature of 250-650 C. for 1-60 seconds, or by washing the surface of the carbon fiber raw material 10 with an organic solvent. In the embodiment by using the organic solvent to wash the surface of the carbon fiber raw material 10, the organic solvent may be acetone or chloroform.

[0036] In the plasma surface treatment step, a plasma gas flow with a predetermined power is provided to act on the carbon fiber 11 without the first oiling agent, such that the surface of the carbon fiber 11 is formed with a plasma-modified configuration 111 (shown in FIG. 4) which is relatively rougher.

[0037] In the sizing step, the plasma-modified configuration 111 on the surface of the carbon fiber 11 is coated with a second oiling agent 13 to obtain the carbon fiber raw material 10 having the second oiling agent 13 thereon (as shown in FIG. 5). In practice, the second oiling agent 13 is coated on the surface of the carbon fiber 11 by soaking or immersing. The second oiling agent 13 may be a thermosetting resin oiling agent or a thermoplastic resin oiling agent. In an embodiment that the second oiling agent 13 is a thermoplastic resin oiling agent, the second oiling agent 13 may be one of polyurethane (PU), polyethene (PE), polypropylene (PP), and acrylic.

[0038] Thereby, through the carbon fiber surface oiling agent changing method of the present invention, the oiling agent on the surface of the carbon fiber can be replaced with a desired oiling agent in a relatively more active and reliable manner. Particularly, it is suitable for replacing a thermosetting resin oiling agent on the surface of the existing carbon fiber raw material with a thermoplastic resin oiling agent so that it can be applied to various kinds of electrical and electronic parts, mechanical parts and automobile parts which are formed by injection molding.

[0039] In the plasma surface treatment step, an atmospheric plasma gas flow, a low-pressure plasma gas flow, a microwave plasma gas flow, or a glow plasma gas flow with a power of 100-10000 watts may be used to act on the carbon fiber for 10-1000 milliseconds. Since the plasma gas flow contains particles having energy, the impurities that originally adhere to the surface of the carbon fiber can be broken to form small molecules and blown away through the physical reaction (collision) and chemical reaction of the plasma gas flow, enabling the surface of the carbon fiber to be roughened and provided with functional groups, which is beneficial to achieve high-quality interface bonding of the carbon fiber and the thermoplastic resin oiling agent in the subsequent sizing step, thereby enhancing the characteristics of carbon fiber composite materials.

[0040] Furthermore, the plasma surface treatment of the present invention belongs to a dry-type surface treatment technique. This not only prevents the carbon fiber from generating additional impurities or sediment but also reduces the working time and working procedure of drying after the completion of the plasma surface treatment. As shown in FIG. 6, after the sizing step, the carbon fiber raw material having the second oiling agent is processed with at least one drying step, so that the second oiling agent is firmly adhered to the surface of the carbon fiber in a drying or wind-drying manner.

[0041] Specifically, the carbon fiber surface oiling agent changing method of the present invention is suitable for replacing a thermosetting resin oiling agent on the surface of the existing carbon fiber raw material with a thermoplastic resin oiling agent so that it can be applied to various kinds of electrical and electronic parts, mechanical parts and automobile parts which are formed by injection molding. Particularly, the surface of the carbon fiber is roughened and is provided with functional groups, which is beneficial to achieve high-quality interface bonding of the carbon fiber and the thermoplastic resin oiling agent in the subsequent sizing step, thereby enhancing the characteristics of carbon fiber composite materials.

[0042] Although particular embodiments of the present invention have been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the present invention. Accordingly, the present invention is not to be limited except as by the appended claims.