New fabric coatings
Certain outdoor garments and indoor furnishings are coated with chemicals giving water repellency. Yet the family of perfluorochemicals (PFC-C8) involved is toxic and harmful to the environment, while alternative textile treatments provide lower performance. The EU-funded TEX-SHIELD(opens in new window) (Environmental friendly and durable oil and water repellence finish on technical textiles) project examined cost-effective alternatives to C8 chemistry. The study also considered ways of eliminating PFC-C8 byproducts, reducing toxicity, and improving the function of textile coatings. Researchers concluded that alternatives were most likely to come from the PFC-C6 family, which break down in the environment. Alternatives were still likely to contain fluorine, and hybrids such as fluoro-silicones may offer an acceptable compromise. TEX-SHIELD evaluated PFCs having carbon chains less than eight, polysiloxane loaded with silica nanoparticles, and a fluorine-free nano-silica. The first approach was closest to market, and used commercially available materials, although offer worse performance than PFC-C8s. Researchers concluded that the second approach is commercially feasible and more environmentally friendly, yet performs worse than PFC-C8. The third approach was also feasible, and may perform better than PFC-C8, although still requires considerable development. The group considered further alternatives including application of thin coatings of PFC-C6 using plasma, a water-borne UV curable system, and a filled polysiloxane. While all options showed some potential, further exploration is necessary. TEX-SHIELD's work advanced understanding of suitable textile coatings, laying the groundwork for future development. Suitable materials would offer environmental, health and economic benefits for Europe.
