Guanghou Wang, Mingkang Teng, Dexun Shen, et al. Positron annihilation characteristics in high energy electron-irradiated polyethylene and polypropylene[J]. Nuclear techniques, 1990, 13(1): 14-18.
Guanghou Wang, Mingkang Teng, Dexun Shen, et al. Positron annihilation characteristics in high energy electron-irradiated polyethylene and polypropylene[J]. Nuclear techniques, 1990, 13(1): 14-18.DOI:
Positron annihilation lifetime spectra and Doppler broadening are used to investigate high energy (12MeV) electron-irradiated polyethylene and polypropylene. With increase of the electron dose less than 160kGy the short lifetime component of positrons for PP becomes longer while the intensity of the medium lifetime component decreases. When the irradiation dose reaches 320 kGy the lifetime components in the irradiated-PP are similar to those in virgin samples. However
the intensity of the longest lifetime component is nearly unchanged with increase of the irradiation dose. In the irradiated-PE both intensity of the longer lifetime component and shape parameter of Doppler broadening decrease quite a bit at the beginning but remain constant after 80 kGy electron irradiation. The mechanisms of different effects of high energy electron irradiation on the two polymers are discussed.
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