Making Nanoparticles Mega: Scaling-up the Synthesis of Gold Nanoparticle-Wool Fibre Composites

T.W. Nilsson, J.H. Johnston
Victoria University of Wellington and the MacDiarmid Institute of Advanced Materials, NZ

Keywords: gold nanoparticles, wool, scale-up, dyeing, commercialisation


Gold nanoparticles exhibit intense surface plasmon resonances in the visible region of light. This property allows them to be employed as stable colourants for fine New Zealand wool fibres. A novel proprietary approach for the synthesis of gold nanoparticle-wool fibre composites has been developed by Professor James H Johnston and Dr Kerstin A Lucas from Victoria University of Wellington and Noble Bond Ltd. These nanocomposites are being fabricated into luxury garments, apparel, textiles and carpets for international markets. Commercialisation of the nanocomposites necessarily required scaling-up their synthesis from the laboratory-scale to the kilogram-scale. Significant issues arise when large volumes of gold colloids are synthesised, as uniform heating and mixing is difficult to achieve. Additionally, uniformly colouring large wool samples is a hugely significant and recurring issue in the wool dyeing industry. Despite these difficulties, 100L gold colloids have been successfully and reproducibly synthesised, and used to uniformly colour wool fibres. Based this success, larger scale reactors have been designed and implemented. Gold colloids and nanocomposites were characterised with UV-visible spectroscopy, TEM, EDS and SEM. The presented results show that such nanomaterials can be successfully synthesised on a larger than laboratory-scale and provide insights into the scaling-up of other nanomaterials.