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An efficient reflux extraction of polyethylene wax (PEW) in soil is presented, followed by molecular structure characterization methods to explore its degradation mechanism. To more realistically simulate the actual degradation of PE film powders in soil, low density PE (M=5 000) powders, being used as simulated PEW residue sample, were uniformly mixed with soil and then recovered by reflux extraction with decahydronaphthalen (decalin) at 90°C for 60 min. The average recovery of PEW from fortified soils was 96.5%with the developed reflux extraction procedure. The recovered PEW residue samples were characterized by infrared spectroscopy (IR), element analysis (EA), X-ray fluorescence (XFR), and high-temperature gel permeation chromatography (GPC). The results from spectra analysis show that there were no significant changes in molecular structures and molecular mass distribution of PEW samples after the reflux extraction, which demonstrate the reliability of this method. These results also indicate that the reflux extraction procedure and analytical methods of characterization could serve as a novel measurement technique to evaluate the degradation of low-density PE powders in soil over time.