Influences of Absorbed Dose Rate on the Mechanical Properties and Fiber-Matrix Interaction of High-Density Polyethylene-Based Carbon Fiber Reinforced Thermoplastic Irradiated by Electron-Beam

Se Kye Park; Dong Yun Choi; Du Young Choi; Dong Yun Lee; Seung Hwa Yoo

doi:10.3390/polym12123012

Influences of Absorbed Dose Rate on the Mechanical Properties and Fiber-Matrix Interaction of High-Density Polyethylene-Based Carbon Fiber Reinforced Thermoplastic Irradiated by Electron-Beam

Polymers (Basel). 2020 Dec 16;12(12):3012. doi: 10.3390/polym12123012.

Authors

Se Kye Park^{1

2}, Dong Yun Choi¹, Du Young Choi³, Dong Yun Lee², Seung Hwa Yoo⁴

Affiliations

¹ Daegyeong Division, Korea Institute of Industrial Technology, Yeongcheon 38822, Gyeongsangbuk-do, Korea.
² Department of Polymer Science and Engineering, Kyungpook National University, Daegu 41566, Gyeongsangbuk-do, Korea.
³ Carbon Materials Application R&D Group, Korea Institute of Industrial Technology, Jeonju 54853, Jeollabuk-do, Korea.
⁴ Department of Quantum System Engineering, College of Engineering, Jeonbuk National University, Jeonju 54896, Jeollabuk-do, Korea.

Abstract

In this study, a high-density polyethylene (HDPE)-based carbon fiber-reinforced thermoplastic (CFRTP) was irradiated by an electron-beam. To assess the absorbed dose rate influence on its mechanical properties, the beam energy and absorbed dose were fixed, while the absorbed dose rates were varied. The tensile strength (TS) and Young's modulus (YM) were evaluated. The irradiated CFRTP TS increased at absorbed dose rates of up to 6.8 kGy/s and decreased at higher rates. YM showed no meaningful differences. For CFRTPs constituents, the carbon fiber (CF) TS gradually increased, while the HDPE TS decreased slightly as the absorbed dose rates increased. The OH intermolecular bond was strongly developed in irradiated CFRTP at low absorbed dose rates and gradually declined when increasing those rates. X-ray photoelectron spectroscopy analysis revealed that the oxygen content of irradiated CFRTPs decreased with increasing absorbed dose rate due to the shorter irradiation time at higher dose rates. In conclusion, from the TS viewpoint, opposite effects occurred when increasing the absorbed dose rate: a favorable increase in CF TS and adverse decline of attractive hydrogen bonding interactions between HDPE and CF for CFRTPs TS. Therefore, the irradiated CFRTP TS was maximized at an optimum absorbed dose rate of 6.8 kGy/s.

Keywords: absorbed dose rate; carbon fiber-reinforced thermoplastic; electron-beam irradiation; fiber–matrix interaction; tensile strength.