Effects of MgO Nanoparticles on Viscoelastic Properties of Linear Low-Density Polyethylene

Abstract

Linear Low-Density Polyethylene (LLDPE) is a semicrystalline polymer with potential for use in High-Voltage Direct Current (HVDC) transmissions. Its mechanical and electrical insulating properties can be improved by addition of nanofillers to the pure LLDPE matrix. This paper deals with the influence of magnesium oxide nanoparticles (MgO) with content from 0 to 10 wt. % on the viscoelastic properties of LLDPE. The reinforcing effect as a result of immobilization of the polymer chains on the filler surface after incorporation of MgO nanoparticles was deduced from analysis of DMA measurements. Three relaxation processes associated with chain motion in amorphous, interfacial and crystalline regions were identified in the temperature dependence of loss modulus and damping factor tanδ in all studied samples. Temperatures associated with the first two processes were slightly influenced by the presence of MgO nanoparticles, in contrast to the third one, in which a more significant shift to higher temperatures was observed in comparison to pure LLDPE.