High-Energy Heavy-Ion Irradiation Effects in Makrofol-KG Polycarbonate and PET R. C. Ramola, 1 Ambika Negi, 1 Anju Semwal, 1 Subhash Chandra, 1 J. M. S. Rana, 1 R. G. Sonkawade, 2 D. Kanjilal 2 1 Department of Physics, HNB Garhwal University, Badshahi Thaul Campus, Tehri Garhwal 249199, India 2 Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067, India Received 29 October 2009; accepted 7 December 2010 DOI 10.1002/app.33932 Published online 30 March 2011 in Wiley Online Library (wileyonlinelibrary.com). ABSTRACT: This experimental study investigated the modification of optical, structural and morphological prop- erties of Makrofol-KG and Polyethylene Terephtalate (PET) by irradiation of 120 MeV Ni þ9 ions at fluences ranging from 1  10 10 to 1  10 12 ion/cm 2 . Optical and structural properties were studied by UV–visible spectros- copy and X-ray diffraction (XRD) method, respectively. XRD studies of pristine and irradiated polymers revealed that crystallinity decreased after irradiation with swift heavy ions. The UV–visible spectrum displayed a shift in absorbance edge toward higher wavelength at higher flu- ence, which can be correlated with transition involved in polymers. Fourier transform infrared spectroscopy spectra were analyzed to investigate the changes in the chemical/ structural properties of these polymers. The Makrofol-KG is found to exhibit more pronounced modification com- pared to PET after irradiation by swift heavy ions. The surface morphology studied by atomic force microscopy showed that the roughness of polymers surface increased with increasing fluence. V C 2011 Wiley Periodicals, Inc. J Appl Polym Sci 121: 3014–3019, 2011 Key words: makrofol-KG polycarbonate; PET; ion beam; XRD; UV-visible; FTIR; AFM INTRODUCTION High-energy ion bombardment induced modifica- tions in polymeric materials constitute an interest- ing and involved field of research. The swift heavy ions (SHI) at velocity of the order of Bohr velocity lose their energy mainly via electronic ex- citation and ionizations. The deposited energy gets converted into atomic motion and finally leads to several structural and chemical modifica- tions within a cylindrical zone of a few nano- meters in diameter. 1–4 Polycarbonates such as Makrofol are insensitive to light charged particle, X-rays and gamma rays. Therefore, they offer a very convenient way of detecting heavy ions in the studies of cosmic rays, heavy ion nuclear reac- tions, and exploration of super heavy elements. These are also most suitable for shielding of devi- ces and in micro filter technology. 5,6 For instance, it is used in preparing track etched membrane to be used as microfilters. Other applications include its use for ion track recording and as packaging material. Similarly, polyethylene terephthalate (PET) is known for its various applications in capacitors, graphics, recording tapes, etc. It offers good design flexibility and is also lighter and sturdier than most other alternatives, particularly glass. Passage of SHI in these materials creates large- scale lattice defects due to radiation damage along the path of the ion. This in turns induces the for- mation and transport of reactive species that are able to permanently change the physical and chemical properties of these solid state nuclear track detectors. 7 Several studies have been per- formed on the radiation-induced degradation in Makrofol polycarbonate using different kinds of radiations, such as gamma rays, 8 electron beam, 9 neutrons, 10 and heavy ions. 11 Because of the pres- ence of aromatic ring in its polymeric structure, PET has a high melting point and superior me- chanical strength. Moreover, it is resistant to heat and moisture, and is virtually nonreactive with many chemicals. Several studies have shown that irradiation of polymers with SHI leads to a wide variety of changes in properties. 12–15 Singh et al. 16 reported a study of electrical and structural prop- erties of PET films irradiated by 50 MeV lithium ions. This investigation aims at studying the effects of Ni ion beam irradiation on Makrofol-KG and PET. The chemical structure of Makrofol-KG (a) and PET (b) are given below: Correspondence to: R. C. Ramola (rcramola@gmail.com). Journal of Applied Polymer Science, Vol. 121, 3014–3019 (2011) V C 2011 Wiley Periodicals, Inc.