کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5348859 | 1503636 | 2015 | 9 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
The influence of cross-linking and clustering upon the nanohole free volume of the SHI and γ-radiation induced polymeric material
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی تئوریک و عملی
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
The effects of swift heavy ions and gamma radiations upon the nano-scale free volume of the polymethylemethacrylate (PMMA) polymer were investigated using positron annihilation lifetime spectroscopy. The polymer samples were (a) irradiated by 50Â MeV Li3+ ion beam to the fluences ranging from 1Â ÃÂ 1011 to 5Â ÃÂ 1012Â ions/cm2 and (b) exposed to gamma radiation at various doses ranging from 250 to 1000Â kGy. The amorphization was observed in XRD study after ion irradiation and gamma exposure. The absorption edge in the UV-visible study shifted towards the higher wavelength regime leading to decrease of the band gap energy in both cases of irradiations. The formation of new bands at positions 1570, 1560 and 1542Â cmâ1 were observed in FTIR study of gamma radiation exposed sample at 750Â kGy. The cluster formation was seen in the SEM images. The nano-scale free volume (Vf) of the Li3+ ions irradiated PMMA samples was observed to be decreased at fluences of 1.0Â ÃÂ 1011, 5.0Â ÃÂ 1011 and 2.5Â ÃÂ 1012Â ions/cm2 due to ion induced cross-linking of the polymeric chains. The values of hole radius (R) and Vf were increased at fluence of 5.0Â ÃÂ 1012Â ions/cm2, it could be due to the clustering induced at higher fluences. The gamma exposures of the samples lead to decrease of the values of R and Vf.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Applied Surface Science - Volume 328, 15 February 2015, Pages 482-490
Journal: Applied Surface Science - Volume 328, 15 February 2015, Pages 482-490
نویسندگان
Paramjit Singh, Rajesh Kumar, Rajinder Singh, Anirban Roychowdhury, D. Das,