Temperature dependence of creep behavior of PP-MWNT nanocomposites

摘要

The creep behavior of poly(propylene)-multi-walled carbon nanotube (MWNT) composites has been studied with short term tensile creep tests at different temperatures and is discussed in relation to the structural characteristics determined by AFM, DSC, and polarized light microscopy. Master curves of creep compliance have been constructed using a time-temperature superposition (TTS) concept based on the William-Landel-Ferry (WLF) equation. The nanocomposites have shown an increase in creep compliance with increasing temperature as a consequence of temperature-activated motion of the polymer chains. This is critically discussed in the light of activation enthalpy and other influencing factors such as polymer-nanotube interaction and thermal expansion coefficients following semi-empirical approximations.