Nano-Filler Dispersion in Thermoplastics

Most polymers use fillers to improve the polymer’s mechanical and physical properties or simply to bulk them out to reduce cost. The potential benefits of nano-fillers in polymers have been recognised for many years; however, the challenge has been to disperse them effectively using conventional high-shear mixing technologies such as twin-screw extruders. If nano-fillers such as graphene can be effectively dispersed in thermoplastics it offers the potential of polymers with significantly improved mechanical properties, electrical conductivity and capacitance, barrier properties against gas diffusion that would find use in aerospace, automotive and packaging applications.

The Rapid Powders process was originally developed as a dispersion technique for nano-fillers in thermoplastics. In essence, the polymer as a powder, is coated using the Rapid Powders process with nano-fillers such as graphene, carbon black, carbon nano tubes, clay, silver, titania, fumed silica.

The filler dispersion is preserved, and the composite powder is then consolidated by normal compounding methods. These include single or double screw extrusion into polymer pellets for further processing, by extrusion or injection moulding, into semi-fabricated forms or finished components respectively. The range of thermoplastic composites produced is broad from low-density polyethylene LDPE, to polyether ether ketone PEEK, as the thermoplastic matrix.