FTIR ANALYSIS OF IRRADIATED FOOD-GRADE PVC FILMS
Resumo
This work aimed to investigate the influence of ionizing radiation (gamma radiation and accelerated electrons) at commercial doses of 1, 2 and 4 kGy on optical properties of PVC films used as food packaging. FTIR was carried out for range of 4000 to 400 cm-1 by direct measurement. Polyene formation was measured with spectrophotometry at wavelength of 400 nm. FTIR of irradiated samples reveals reduction of absorbance of carbon-hydrogen (methylene) and carbon-chloride bands suggesting PVC scission due to dehydrochlorination reactions. Furthermore, polyene formation demonstrated increase on irradiated samples because of scission reactions on food-grade PVC films. This observation confirms polymeric radiolysis mechanisms promoted by gamma-rays or accelerated electrons.
Referências
COLOMBANI J, RAFFI J, GILARDI T, TROULAY M, CATOIRE B, KISTER J. 2006. ESR studies on poly (vinyl chloride) irradiated at medium and high doses. Polym Degrad Stabil 91(7): 1619-1628.
COLOMBANI J, LABED V, JOUSSOT-DUBIEN C, PÉRICHAUD A, RAFFI J, KISTER J, ROSSI C. 2007. High doses gamma radiolysis of PVC: mechanisms of degradation. Nucl Instrum Meth Phys Res B 265(1): 238-244.
GARCÍA-CASTAÑEDA C, BENAVIDES R, MARTÍNEZ-PARDO ME, URIBE RM, CARRASCO-ÁBREGO H, MARTÍNEZ G. 2010. Crosslinking of rigid PVC by ionizing radiation to improve its thermal properties. Radiat Phys Chem 79(3): 335-338.
HAJI-SAEID M, SAMPA MHO, CHMIELEWSKI AG. 2007. Radiation treatment for sterilization of packaging materials. Radiat Phys Chem 76: 1535-1541.
LABED V, OBEID H, RESSAYRE K. 2013. Effect of relative humidity and temperature on PVC degradation under gamma irradiation: Evolution of HCl production yields. Radiat Phys Chem 84: 26-29.
LAVERNE JA, CARRASCO-FLORES EA, ARAOS MS, PIMBLOTT SM. 2008. Gas production in the radiolysis of poly (vinyl chloride). J Phys Chem 112(15): 3345 – 3351.
NADIMICHERLA R, KALLA R, MUCHAKAYALA R, GUO X. 2015. Effects of potassium iodide (KI) on crystallinity, thermal stability, and electrical properties of polymer blend electrolytes (PVC/PEO:KI). Solid State Ionics 278: 260-267.
REDDEPPA N, SHARMA AK, NARASIMHA RAO VVR, CHEN W. 2013. Preparation and characterization of pure and KBr doped polymer blend (PVC/PEO) electrolyte thin films. Microelectron Eng 112: 57-62.
RODOLFO JR A, MEI LHI. 2007. Mecanismos de Degradação e Estabilização Térmica do PVC. Polímeros: Ciência e Tecnologia 17(3): 263-275.
ROUIF S. 2004. Radiation cross-linked plastics: a versatile material solution for packaging, automotive, electrotechnic and electronics. Radiat Phys Chem 71(1-2): 527-530.
ROUIF S. 2005. Radiation cross-linked polymers: recent developments and new applications. Nucl Instrum Meth Phys Res B 236(1-4): 68-72.
VINHAS GM, SOUTO MAIOR RM., DE ALMEIDA YMB. 2004a Radiolytic degradation and stabilization of poly (vinyl chloride). Polym Degrad Stabil 83: 429-433.
VINHAS GM, SOUTO-MAIOR RM, DE ALMEIDA YMB, NETO BB. 2004b. Radiolytic degradation of poly (vinyl chloride) systems. Polym Degrad Stabil 86(3): 431-436.
ZHU HM, JIANG XG, YAN JH, CHI Y, CEN KF. 2008. TG-FTIR analysis of PVC thermal degradation and HCl removal. J Anal Appl Pyrol 82: 1-9.
ZYGOURA PD, PALEOLOGOS EK, KONTOMINAS MG. 2011. Changes in the specific migration characteristics of packaging-food simulant combinations caused by ionizing radiation: effect of food simulant. Radiat Phys Chem 80: 902-910.
WOO L, SANDFORD CL. 2002. Comparison of electron beam irradiation with gamma processing for medical packaging materials. Radiat Phys Chem 63: 845-850.
WU J, CHEN T, LUO X, HAN D, WANG Z, WU J. 2014. TG/FTIR analysis on co-pyrolysis behaviour of PE, PVC and PS. Waste Manage 34: 676-682.