A carbon fiber reinforced thermoplastic (CFRTP) was irradiated with a high energy electron-beam. As a result, the tensile strength of high-density polyethylene (HDPE)-based CFRTPs was significantly improved by gradually increasing the electron-beam dose. It was confirmed that the adhesion between CF and HDPE was improved and the surface properties of CF and HDPE were readily modified by electron-beam. It was verified from spectroscopic analysis that various oxygencontaining functional groups were formed on the surface of CF and HDPE by irradiation and we believe that strong attractive interactions took place among these functional groups at the interface of CFs and HDPE. Finally, it was conclusive that electron-beam irradiation provided two main effects on CFRTPs. One was cross-linking of thermoplastic resin for efficient load transfer from resin to CF and the other was formation of surface functional group and attractive interaction of these functional groups at the interface of fiber and matrix. These two effects showed synergetic contribution to enhance the mechanical properties of CFRTP.

    Abstract
    1 Introduction
    2 Experimental
        2.1 Raw materials
        2.2 Specimen preparation
        2.3 Electron-beam irradiation
        2.4 Characterization
    3 Results and discussion
    4 Conclusions
    Acknowledgements 
    References

• Soonyoung Jung(Daegyeong Regional Division, Korea Institute of Industrial Technology, Department of Advanced Organic Materials Science and Engineering, Kyungpook National University)
• Se kye Park(Daegyeong Regional Division, Korea Institute of Industrial Technology, Department of Polymer Science and Engineering, Kyungpook National University)
• Han‑do Ghim(Department of Advanced Organic Materials Science and Engineering, Kyungpook National University)
• Dong Yun Lee(Department of Polymer Science and Engineering, Kyungpook National University)
• Seung Hwa Yoo(Daegyeong Regional Division, Korea Institute of Industrial Technology)