| Ion beam modifications of materials and their applications Rajesh Kumar1; 1UNIVERSITY SCHOOL OF BASIC AND APPLIED SCIENCES, GURU GOBIND SINGH INDRAPRASTHA UNIVERSITY, New Delhi, India; PAPER: 539/Physics/Regular (Oral) SCHEDULED: 17:10/Wed. 30 Nov. 2022/Andaman 2 ABSTRACT: The irradiation of polymeric materials with SHI results in a change of their free volume properties which have strong correlation with their macroscopic properties. Positron annihilation lifetime spectroscopy (PALS) has been developed into a powerful characterization tool for the study of free volume and free volume fraction in polymers. We have used different type of polymers with different thickness and irradiated with different ions of energy and flunces from 15 UD Pelletron accelerators at Inter University Accelerator Centre (IUAC), New Delhi, India. Characterizations of the effect of ion irradiation on free volume have been done by PALS and other techniques like XRD, AFM, UV-Vis, FTIR, SEM etc. The average free volume and fractional free volume obtained from long lived component, attributed to ortho-positronium (o-Ps) lifetime, are found to decrease with the fluence in both the cases. With increasing fluence, scissioned segments cross-link randomly, resulting in a decrease of average free volume due to overlapping of tracks [1-5]. The detailed results will be discussed during the presentation. References: 1. Ion induced modification in free volume in PN-6 and PES polymers by positron annihilation lifetime studies, Rajesh Kumar, R. Prasad, NIM B 256 (2007) 238-242. (Elsevier) 2. UV–visible and infrared spectroscopic studies of Li3+ and C5+ irradiated PADC polymer, P. Singh and Rajesh Kumar, Results in Physics, 3 (2013) 122-128. (Elsevier) 3. Physico-chemical modifications induced in Makrofol-N polycarbonate by swift heavy ions, Rajesh Kumar, H.S.Virk, K.C.Verma, U.De, A.Saha, R. Prasad, NIM B, 251 (2006) 163-166. (Elsevier) 4. Physical and chemical response of 70 MeV carbon ion irradiated polyether sulphone polymer, Rajesh Kumar, U.De, R. Prasad, NIM B248 (2006) 279-283. (Elsevier) 5. Study of optical band gap and carbonaceous clusters in swift heavy ion irradiated polymers with UV–Vis spectroscopy, Rajesh Kumar, R. Prasad, H.S. Virk et.al, 266 (2008)1788-1792. (Elsevier) |
