Polymer Engineering and Science, Vol.50, No.8, 1633-1645, 2010
Ethylene Maleated Amorphous Propylene Compatibilized Polyethylene Nanocomposites: Stress and Temperature Effects on Nonlinear Creep
The effects of stress and temperature on the nonlinear creep behavior of linear low-density polyethylene (LLDPE) nanocomposites reinforced with montmorillonite-layered silicate (MLS) nanoclay and compatibilized with an amorphous maleated ethylene copolymer (amEP) is investigated. To study the effect of stress on the creep resistance of these materials, creep tests were conducted at different stress levels (10, 25, and 50% yield stress). The effect of temperature was examined by analyzing the creep and recovery of the films at temperatures in the range of -100 to 25 degrees C. The individual creep compliance curves for each stress level and temperature were fitted to both the Burgers model and the Kohlrausch-Williams-Watts (KWW) function. The results indicate that modification of the polyethylene results in a suppression of relaxation times but the temperature trends are reversed below the beta transition temperature. Filled systems exhibited a distribution in relaxation times whose trend matched the relaxation time trends in both Burger and KWW models. POLYM. ENG. SDI., 50:1633-1645, 2010. (C) 2010 Society of Plastics Engineers