Steffen Schellenberger will defend his licentiate thesis entitled “Why Does It Always Rain On Me – Properties of Alternative Durable Water Repellent Chemicals for Textiles.”
Environmental pollution caused by long-chain perfluoroalkyl acids (PFAAs) – organic chemicals with confirmed levels of toxicity, a propensity for bioaccumulation and extreme environmental persistence – has given rise to global environmental concerns. Functional textiles containing durable water repellents (DWRs) that are based on side-chain fluorinated polymers are noted to be major contributors to the diffuse release of PFAAs. These emissions result from either a) the release of impurities in textiles and b) the gradual degradation of the polymers. Nevertheless, the properties of DWRs based on long-chain perfluoroalkyl chains result in exceptional material performance in repellent textiles and are therefore hard to replace without detriment to textile quality. This thesis aims to characterize the currently available DWR alternatives by assessing their technical performance and potential as hazardous chemicals with respect to estimated emission scenarios. The work carried out herein suggests that by taking a segmented perspective of the textile market, substitution of fluorinated materials with more environmentally benign alternatives, where peak material performance is not required, might offer a more sustainable solution. In addition, the thesis proposes directions for future research that are needed for a more thorough and robust understanding of the environmental fate of DWR-polymers and to reduce diffuse emissions of PFAAs.