Arab J Sci Eng (2011) 36:541–552 DOI 10.1007/s13369-011-0065-5 RESEARCH ARTICLE - CHEMISTRY Nadra Kerboua · Karim Moussaceb · Mustapha Kaci · Djafer Benachour · Tahar Sadoun · Nabila Rouba Modeling of the Kinetic Degradation of Unstabilized and HALS-Stabilized LDPE Films in Natural Aging Received: 28 May 2010 / Revised: 16 September 2010 / Accepted: 7 October 2010 / Published online: 18 June 2011 © King Fahd University of Petroleum and Minerals 2011 Abstract In this work, we propose new mathematical models describing the kinetic degradation of unstabilized low-density polyethylene (LDPE) and LDPE stabilized with hindered amine light stabilizers (HALS). The samples were exposed to natural weathering conditions, and the degradation was measured by a change in elongation at break with time. The mathematical approach developed was based on multiple linear regression analysis (MLRA). We tested the reliability of the selected models using four statistical criteria: residual var- iance, coefficient of determination, Student test and Fisher–Snedecor test. The linear systems resulting from the MLRA were solved using the Cholesky method. The results showed that the polynomial models developed to predict elongation at break were reliable for both types of samples under natural weathering conditions. The experimental half-life times are close to those predicted by the models. Keywords Low density polyethylene · Modeling · Degradation · Elongation at break N. Kerboua · M. Kaci · T. Sadoun · N. Rouba Laboratoire des Matériaux Organiques (LMO), Université Abderrahmane Mira, 06000 Bejaia, Algeria K. Moussaceb (B ) Laboratoire de Technologie des Matériaux et de Génie des Procédés (LTMGP), Université Abderrahmane Mira, 06000 Bejaia, Algeria E-mail: karimmoussaceb@yahoo.fr D. Benachour Laboratoire de Génie des Polymères (LGP), Université Ferhat Abbas, 19000 Sétif, Algeria 123