TY - JOUR
T1 - Combined UV-irradiation and pyrolysis-GC/MS approach for evaluating the deterioration behavior of ethylene vinyl acetate
AU - Yamada, Kanako
AU - Kumagai, Shogo
AU - Shiratori, Toshikazu
AU - Kameda, Tomohito
AU - Saito, Yuko
AU - Watanabe, Atsushi
AU - Watanabe, Chuichi
AU - Teramae, Norio
AU - Yoshioka, Toshiaki
N1 - Funding Information:
This work was supported by JSPS KAKENHI Grant Number 19H04306 .
Publisher Copyright:
© 2021
PY - 2021/8
Y1 - 2021/8
N2 - Ethylene vinyl acetate (EVA), commonly used to encapsulate photovoltaic (PV) modules, deteriorates on prolonged exposure to sunlight. In this work, fresh and deteriorated EVA samples prepared by UV irradiation (500 W m−2) over different periods (0–168 h) are characterized by conventional elemental analysis, microscopic observations, Fourier transform infrared (FT-IR) spectroscopy, and thermogravimetry. To the best of our knowledge, this is the first work to employ pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) and micro-UV irradiation combined Py-GC/MS (UV/Py-GC/MS) to investigate the deterioration behavior of EVA, using in-situ identification of gases liberated during UV irradiation, such as H2O, CO2, ketones, acetic acid, and lactones. In addition, the deterioration of the thermal stability on aging is confirmed using evolved gas analysis-mass spectrometry (EGA-MS). UV/Py-GC/MS revealed that acetaldehyde, acetone, acetic acid, γ-butyrolactone, succinic anhydride, and cyclobutanone are produced during UV irradiation. In addition, Py-GC/MS identified cyclopentanone, citraconic anhydride, γ-valerolactone, and cyclobutanone from the UV deteriorated EVA samples, which suggested the presence of ketone and lactone structures in the deteriorated EVA. This work establishes the combined usage of UV irradiation and Py-GC/MS as a promising method to investigate UV deterioration behavior in greater detail. These findings may contribute to a superior understanding of the breakdown of PV modules by the deterioration of EVA, and lead to the development of UV-resistant encapsulating materials.
AB - Ethylene vinyl acetate (EVA), commonly used to encapsulate photovoltaic (PV) modules, deteriorates on prolonged exposure to sunlight. In this work, fresh and deteriorated EVA samples prepared by UV irradiation (500 W m−2) over different periods (0–168 h) are characterized by conventional elemental analysis, microscopic observations, Fourier transform infrared (FT-IR) spectroscopy, and thermogravimetry. To the best of our knowledge, this is the first work to employ pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) and micro-UV irradiation combined Py-GC/MS (UV/Py-GC/MS) to investigate the deterioration behavior of EVA, using in-situ identification of gases liberated during UV irradiation, such as H2O, CO2, ketones, acetic acid, and lactones. In addition, the deterioration of the thermal stability on aging is confirmed using evolved gas analysis-mass spectrometry (EGA-MS). UV/Py-GC/MS revealed that acetaldehyde, acetone, acetic acid, γ-butyrolactone, succinic anhydride, and cyclobutanone are produced during UV irradiation. In addition, Py-GC/MS identified cyclopentanone, citraconic anhydride, γ-valerolactone, and cyclobutanone from the UV deteriorated EVA samples, which suggested the presence of ketone and lactone structures in the deteriorated EVA. This work establishes the combined usage of UV irradiation and Py-GC/MS as a promising method to investigate UV deterioration behavior in greater detail. These findings may contribute to a superior understanding of the breakdown of PV modules by the deterioration of EVA, and lead to the development of UV-resistant encapsulating materials.
KW - Ethylene vinyl acetate
KW - PV module
KW - Py-GC/MS
KW - UV aging
KW - UV/Py-GC/MS
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U2 - 10.1016/j.polymdegradstab.2021.109623
DO - 10.1016/j.polymdegradstab.2021.109623
M3 - Article
AN - SCOPUS:85107142866
VL - 190
JO - Polymer Degradation and Stability
JF - Polymer Degradation and Stability
SN - 0141-3910
M1 - 109623
ER -