Influence of Different Waxes on the Physical Properties of Linear Low-density Polyethylene

Abstract

The influence of three different waxes on the thermal and mechanical properties of linear low-density  polyethylene (LLDPE) was investigated. The samples were prepared through melt blending in a Brabender  mixer. The thermal properties of the samples were determined using differential scanning calorimetry  (DSC) and thermogravimetric analysis (TGA). The tensile and flow properties of all the samples were  determined and compared. The polymer-wax miscibilities differed with the type of wax used, and with the amount of wax mixed into the polymer. These miscibilities, and accompanying morphologies, had a  strong influence on the flow properties, thermal stabilities and tensile properties of the corresponding  blends.H1wax andM3wax (which are both Fischer-Tropsch paraffin waxes produced by Sasol Wax) both  reduce the apparent viscosity of LLDPE more than EnHance (a Fischer-Tropsch paraffin wax produced by SasolWax as a polyethylene processing lubricant).M3wax had the strongest influence on the melt flow rates (MFI) of the blends, and it had the least influence on the tensile properties of LLDPE. It did, however, strongly reduce its thermal stability.H1 wax, on the other hand, had only a small influence on the thermal stability of LLDPE, but like EnHance it strongly increased the modulus.

KEY WORDS: LLDPE, paraffin wax, melt flow, thermal stability, tensile properties.