Functionalised nanoparticle coating for next generation repellent textiles(REPETEX)

The ongoing concerns and heightened regulation of perfluorocarbons and polyfluoroalkyl substances (PFCs and PFASs), is driving the textile market to search for sustainable alternative chemistries. There is a clear demand for alternative, greener, durable water repellents (DWR) for textiles.The current state of the art that offers the highest level of repellency for both oil and water resistance has been achieved using highly fluorinated chemical substances. Unfortunately, the best performing PFCs, known as C8 due to the 8 carbon atoms in their backbone chain, also raise significant health and environmental concerns that surround the loss of fluorinated by products from textiles. The concern of toxic releases is throughout the life-cycle of the product, from production to end of life. The by-products are known to be bioaccumulative and extremely persistent in the environment/food chain and are possibly carcinogenic. Therefore, within the European Union (EU), perfluorooctanesulfonic acid (PFOS) is regulated to detectable levels of 1 µg per square metre in textile fabrics (European Union, 2006).The project objective will be to deliver cost-effective alternative treatment that will provide textile with durable repellent characteristics. This will be achieved by developing suitable molecular structures which incorporate both low surface energy 22 (mN/m) properties and suitable binding groups to facilitate chemical bonding to the fibre surface yielding a high-performance product. The research innovation of TWI, will provide low surface energy solution through the development of functionalised silica nanoparticles within an aqueous solution that can be incorporated into a water-based ink for printing on to textiles. Functionalised silica (silicon dioxide) nanoparticles play a key role in providing superhydrophobic properties by manipulating the natural surface roughness of the textile microstructure fibres with selectively designed surface chemistry. This provides the uplift required from superhydrophobic performance at the nanoscale level without the use of PFOS. The expertise of the consortium and the supply-chain in place will propel the development into the technical textiles market.Awaiting Public Project Summary