Diamond and Methane Formation From the Chemical Decomposition of Polyethylene at High Pressures and Temperatures
Document Type
Article
Publication Date
1-12-2022
Publication Title
Scientific Reports
Volume
12
Issue
1
Abstract
Polyethylene (C2H4)n was compressed to pressures between 10 and 30 GPa in a diamond anvil cell (DAC) and laser heated above 2500 K for approximately one second. This resulted in the chemical decomposition of the polymer into carbon and hydrocarbon reaction products. After quenching to ambient temperature, the decomposition products were measured in the DAC at pressures ranging from ambient to 29 GPa using a combination of x-ray diffraction (XRD) and small angle x-ray scattering (SAXS). XRD identified cubic diamond and methane as the predominant product species with their pressure–volume relationships exhibiting strong correlations to the diamond and methane equations of state. Length scales associated with the diamond products, obtained from SAXS measurements, indicate the formation of nanodiamonds with a radius of gyration between 12 and 35 nm consistent with 32–90 nm diameter spherical particles. These results are in good agreement with the predicted product composition under thermodynamic and chemical equilibrium.
Controlled Subject
Methane; Decomposition (Mathematics); Polyethylene
Disciplines
Chemistry
Repository Citation
Watkins, E.,
Huber, R.,
Childs, C.,
Salamat, A.,
Pigott, J.,
Chow, P.,
Xiao, Y.,
Coe, J.
(2022).
Diamond and Methane Formation From the Chemical Decomposition of Polyethylene at High Pressures and Temperatures.
Scientific Reports, 12(1),
http://dx.doi.org/10.1038/s41598-021-04206-7