The incorporation of nanoscale particles to enhance the properties of oriented polymers

The incorporation of nanoscale particles into oriented polymers offers the potential to enhance the properties of the resultant nanocomposites. Vapour-grown carbon nanofibres (CNF) are particularly favoured due to high particle shape anisotropy (~10-100), high modulus (240GPa), and are readily available. CNF have been incorporated into polypropylene (PP) using a twin-screw extruder, and the nano-filled material has then been oriented by melt-spinning and solid phase drawing, to produce high modulus, highly oriented tapes, that are then formed into thick section homogeneous sheets, using the hot compaction process developed at the University of Leeds. Preliminary static tensile testing results of uniaxially wound hot compacted samples show an increase in the Young’s modulus from 6.6GPa to 8.5GPa, at the optimum compaction conditions, over unfilled hot compacted PP. Results of varying the blending and compaction conditions are reported, along with investigation into the length, orientation and dispersion of the CNF in the PP matrix, using a variety of techniques including dynamic light scattering (DLS) and scanning electron microscopy (SEM).