Space Charge Accumulation in Linear Low-Density Polyethylene with Surface Fluorination of the Semiconductive Electrode

Several fluorinated polyethylene surface studies have proved that the fluorination reaction can effectively prevent charge from being injected into polyethylene. Therefore, this paper explores the influence of fluorinated electrode on space charge behavior in polyethylene. In this study, the space charge distribution inside polyethylene is measured by laser-PWP (Pressure Wave Propagation) method while altering electrode fluorination duration and fluorination temperature. The experimental results show that measured homocharge injection is increased in polyethylene to which a fluorinated semiconductive electrode is heat pressed. Attenuated Total Reflectance-Infrared (ATR-IR) spectroscopy and Scanning Electron Microscope (SEM) are also performed, revealing that the fluorinated layer of semiconductive electrode on the interface between polyethylene and electrode block impurities from entering polyethylene. The measured space charge distribution, being the planar average amount, also reveals impurity generation since heterocharge formation is observed. As such impurities are blocked, in the meantime the electrodes' homocharge injection remains un-affected, thereby the measured apparent charge is greatly increased.