Effect Of Weathering On The Viscoelastic Behavior Of Ldpe Films

Low density polyethylene films commonly used for greenhouses covering have been aged in sub-Saharan region. Mechanical characterization with a tensile test machine has been performed on polyethylene samples picked up at regular interval thorough the total duration of the aging protocol (0 to 6 months). Young's modulus, elongation at break and tensile strength are the different greatnesses which have allowed following the incidence of ageing on the mechanical properties. The viscoelastic properties were carried out on a creep apparatus. It has been observed that the film deforms according to several steps. They correspond to different flow types; such as instantaneous deformation, viscoelastic and viscoplastic deformation. All are affected with aging time in reason of the micro-structural changes undergone by the material.