Surface modification of polyacrylonitrile-based carbon fiber and its interaction with imide

doi:10.1016/j.apsusc.2006.05.044

Applied Surface Science

Volume 253, Issue 5, 30 December 2006, Pages 2695-2701

https://doi.org/10.1016/j.apsusc.2006.05.044 Get rights and content

Abstract

In this work, sized polyacrylonitrile (PAN)-based carbon fibers were chemically modified with nitric acid and maleic anhydride (MA) in order to improve the interaction between carbon fiber surface and polyimide matrix. Bismaleimide (BMI) was selected as a model compound of polyimide to react with modified carbon fiber. The surface characteristic changing after modification and surface reaction was investigated by element analysis (EA), scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and surface enhanced Raman scattering (SERS). The results indicated that the modification of carbon fiber surface with MA might follow the Diels Alder reaction mechanism. In the surface reaction between modified fibers and BMI, among the various surface functional groups, the hydroxyl group provided from phenolic hydroxyl group and bridged structure on carbon fiber may be the most effective group reacted with imide structure. The results may shed some light on the design of the appropriate surface structure, which could react with polyimide, and the manufacture of the carbon fiber-reinforced polyimide matrix composites.

Introduction

Carbon fibers have been widely used as reinforcement materials in advanced composites because of their relatively low cost and excellent properties, such as high specific strength, stiffness, low expansion coefficient and relative flexibility. However, when applied without previous surface modification, the physical–chemical interaction between carbon fibers and its reinforced matrix is not tough enough due to the inert surface property of carbon fiber, which will directly affect the degree of interfacial adhesion in the composite system. Numerous methods concerning surface treatment, such as chemical method [1], [2], [3], electrochemical method [4], [5], [6], plasma treatment [7], [8], etc., have been developed to increase the quantity of surface functional groups and thus enhance the ability to establish strong interactions between fibers and matrix. Moreover, it is very important to design and introduce the suitable surface functional groups on carbon fiber for different resin matrix. For most systems of fiber-reinforced composites, the matrix usually was chose as epoxy resin. A lot of research works also have been reported on the interface existed between carbon fibers and epoxy resin and the interfacial interaction [9], [10], [11], [12], [13]. Polyimide, due to its unusual properties such as good thermal stability, low dielectric constant, high mechanical strength and chemical inertness, is becoming a strong competitor of matrix in the manufacture of advanced composite materials. The fiber-reinforced polyimide matrix composites with high performance have especial application in aerospace, robots, sports goods, etc. However, the reports relating to the interaction and properties of the carbon fiber/polyimide interface are scarce.

In this paper, we focused on the study about the chemical modification of carbon fiber with different methods and the interaction of surface functional groups thus introduced on carbon fiber and polyimide. Bismaleimide (BMI) was selected as a model compound of polyimide to react with modified carbon fiber. The surface characteristic and morphological changes on carbon fiber were investigated by element analysis (EA), scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and surface enhanced Raman scattering (SERS). The investigation of reaction mechanism between different oxygen-containing carbon fiber surfaces and BMI could serve as a guide for the design of functional groups on carbon fiber and the manufacture of fiber-reinforced polyimide matrix composites.

Section snippets

Materials and surface modification of carbon fibers

The carbon fibers used in this study were polyacrylonitrile (PAN)-based type manufactured by Toray Co. under the trade name of T300B. Before their modification, these commercial fibers were cut into 3–5 mm in length, then washed in the acetone with ultrasound to remove the surface contamination, and finally dried in a vacuum oven at 50 °C, the pretreated carbon fibers were called CF. The other chemicals employed here, such as maleic anhydride (MA), nitric acid, N-methyl-2-pyrrolidinone (NMP) and

Results and discussion

Table 1 presents the EA data measured from three different kinds of carbon fiber sample, which shows an obvious change of element content in samples (including weight content of different element and atomic concentration calculated from the weight content) after different surface modifications. The sized fibers (T300B) usually have a rich-oxygen surface because of the oxygen-containing groups in surface sizing [15] and part of the sizing can be removed from the carbon fiber surface by washing

Conclusions

Different chemical modifications were applied on the sized carbon fibers T300B in order to study the surface characteristic changing occurred on carbon fiber and realize the following interaction between the modified carbon fibers and the matrix, polyimide. Bismaleimide was selected as a model compound of polyimide in this work. AFM, SEM and XPS analysis indicated that the surface-modified CF with MA displayed a rough surface on which β-carbon, bridged structure, –COOH and –COOR groups were

Acknowledgements

The authors are grateful for the supports from the National Natural Science Foundation of China (No. 50333030) and Testing Foundation of Nanjing University.

References (22)

H. Ogawa et al.
Carbon
(1995)
Z.H. Wu et al.
Carbon
(1995)
M. Toyoda et al.
Carbon
(2001)
Y.V. Basova et al.
Electrochem. Commun.
(1999)
E. Theodoridou et al.
Synth. Met.
(1997)
Z.R. Yue et al.
Carbon
(1999)
C.U. Pittman et al.
Carbon
(1999)
G.M. Wu
Mater. Chem. Phys.
(2004)
S.L. Gao et al.
Carbon
(2004)
K.W. Jang et al.
Compos. Sci. Technol.
(1999)

N.G. Yun et al.

Polymer

(2004)

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Surface modification of polyacrylonitrile-based carbon fiber and its interaction with imide

Abstract

Introduction

Section snippets

Materials and surface modification of carbon fibers

Results and discussion

Conclusions

Acknowledgements

Carbon

Carbon

Carbon

Electrochem. Commun.

Synth. Met.

Carbon

Carbon

Mater. Chem. Phys.

Carbon

Compos. Sci. Technol.

Polymer