Fabrication and Characterisation of Polyurethane/Sepiolite Polymer Nanocomposite Foams for Enhanced Energy Absorption

Polymer nanocomposite foams are unique materials that can be chemically, mechanically and structurally controlled in order to maximise the desired properties. Through size, shape and surface modification, the functionality of the foam can be enhanced or altered. This project looks at the incorporation of sepiolite clay nanorods into a polyurethane foam matrix in order to improve the sound vibration absorption properties of open cell flexible foams. Polyurethane foams are light weight, porous materials that can act as good thermal and sound barriers, while sepiolite nanorods have a high aspect ratio associated with the production of well dispersed composites as well as the possibility for the surface chemistry to be easily modified. The sepiolite rods were incorporated into the foam matrix through the mechanical dispersion of the rods into a foam precursor to allow the in-situ polymerisation of the foam matrix and sepiolite nanofiller. Three different grades of sepiolite clay were explored with varying surface chemistry. Cyclic and static compression testing were used to show how the change in surface treatment of the sepiolite lead to an increase in the energy dissipation of the system.