Characterization of the Viscoelastic Mechanical Properties of Ultra High Molecular Weight Polyethylene Fiber Reinforced Composites

Abstract

Abstract This study investigates the effect of fiber orientation on the viscoelastic properties of an ultra high molecular weight polyethylene fiber-reinforced composite with a polyurethane matrix. Samples were prepared with two fiber orientations: [0/90]2 and [±45]2. Dynamic mechanical analysis was performed on the samples from −50 °C to 100 °C at a frequency of 1 Hz with a strain in both samples’ linear region of a tensile stress-strain diagram. The [0/90]2 layup had a storage modulus four times higher than the [±45]2 orientation at −50 °C. The [0/90]2 had a slight increase in storage modulus between 18 °C and 28 °C, but generally decreased with temperature as the polymer chains became more rubbery. The [±45]2 had a consistent decrease in storage modulus over the entire temperature range. The [0/90]2 had the highest loss modulus at temperatures between 35 °C and 100 °C, while the [±45]2 performed best at dissipation of energy around −30 °C. The Tan δ for both fiber orientations increased with temperature, except for the [±45]2, which peaked at 28 °C before decreasing slightly as temperatures increased. At higher frequencies, both the loss and storage modulus increased at a higher percentage for the [±45]2 orientation compared to the [0/90]2.