Spectroscopic Investigations of Optical Bandgap and Search for Reaction Mechanism Chemistry Due to γ-Rays Irradiated PMMA Polymer
Shiv Govind Prasad, Chhagan Lal, A Chapiro, V Rai, C Mukherjee, B Jain, D Raem, B Katuin-Raem, L Maggi, L Segale, E Ochoa Machiste, A Faucitano, A Buttafava, U Conte, K Burg, S Shalaby, J Chung, Y Seong, T Kim, Y Choi, T Kim, H Choi, C Min, H Benmakhlouf, K Chun, H Chung, M Polovka, V Brezova, P Simko, A Goulas, K Riganakos, A Badeka, M Kontominas, H Manjunatha, S Aziz, O Abdullah, M Brza, A Azawy, D Tahir, M Zafar, D Cao, G Yang, M Bourham, D Moneghan, M Avella, M Errico, E Martuscelli, M Zahid, H Park, Y Cho, J Yi, P Ghosh, D Laramore, D Mcgregor, H Karaaslan, B Engin, O Romanenko, P Slepika, O Kvtek, M louf, P Nmecek, V Havrnek, A Mackov, V vork, I Al-Qaradawi, D Abdulmalik, N Madi, M Almaadeed, P Silva, C Albano, R Perera, N Domnguez, R Huszank, E Szilgyi, Z Szoboszlai, Z Szikszai, M Abutalib, A Rajeh, A Sharma, M Chawla, D Gupta, R Kumari, M Bura, N Shekhawat, S Aggarwal, Y Sakurabayashi, T Masaki, T Iwao, M Yumoto, N Madani, D Sardari, M Hosntalab, P Zobdeh, V Lima, U Hossain, T Walbert, T Seidl, W Ensinger, S Prasad, A De
Abstract
Radiation damage and the product formation chemistry in Polymethyl methacrylate (PMMA) due to γ-irradiation have been studied by SEM, XRD, FTIR, and UV-Vis spectroscopy. Co-60 gamma source with a dose rate of 1.707 kGy/hr has been used for irradiation to a total 570 kGy dose. No significant changes in morphology upon such irradiation. Crystallinity decreases at a lower dose and then increases for a higher dose. Crosslinking dominates at lower doses, and chain scission overwhelms at higher doses in the irradiated polymer. Two isosbestic points are formed, and the absorption maxima shift towards a higher wavelength. The optical bandgap energy decreases with the addition of radiation dose. A new FTIR peak at 1638 cm-1 appeared, suggesting the formation of an unsaturation center in the irradiated polymer. Up to a dose of 409 kGy, FTIR absorption peak intensity increases and decreases with further irradiation.