Reference: “In-situ phosphine oxide physical networks: A facile strategy to achieve durable flame retardant and antimicrobial treatments of cellulose” by Rashid Nazir, Dambarudhar Parida, Joel Borgstädt, Sandro Lehner, Milijana Jovic, Daniel Rentsch, Ezgi Bülbül, Anja Huch, Stefanie Altenried, QunRen, Patrick Rupper, Simon Annaheim and Sabyasachi Gaan, 9 December 2020, Chemical Engineering Journal.DOI: 10.1016/j.cej.2020.128028 For firefighters and other emergency service personnel, protective clothing provides the most important barrier. For such purposes, cotton is mainly used as an inner textile layer that needs additional properties: For example, it must be fireproof or protect against biological contaminants. Nevertheless, it should not be hydrophobic, which would create an uncomfortable microclimate. These additional properties can be built into the cotton fibers by suitable chemical modifications. Gaan knows the chemistry of cotton fibers well and has spent many years at Empa developing flame retardants based on phosphorus chemistry that are already used in many industrial applications. Now he has succeeded in finding an elegant and easy way to anchor phosphorous in form of an independent network inside the cotton. To render additional protective functionalities to the flame retardant cotton developed at Empa, the researchers also incorporated in situ generated silver nanoparticles inside the fabric. This works nicely in a one-step process together with generating the phosphine oxide networks. Silver nanoparticles provide the fiber with antimicrobial properties and survive 50 laundry cycles, too. Meanwhile, this newly developed phosphorus chemistry and its application is protected by a patent application. “Two important hurdles remain,” Gaan says. “For future commercialization we need to find a suitable chemical manufacturer who can produce and supply trivinylphosphine oxide. In addition, trivinylphosphine oxide has to be REACH-registered in Europe.”
