Novel bio-based flame retardant
The incorporation of biological resources for developing flame retardant is a promising approach to fabricate durable flame retardant fabrics. Now, a novel bio-based flame retardant ammonium salt of taurine phosphonate (PTau) was successfully synthesised from taurine and grafted onto the nylon-cotton (NYCO) blend fabrics by covalent bonds. Both the flame retardancy and washing durability of PTau treated NYCO fabrics were improved significantly. The limiting oxygen index (LOI) value of PTau-NYCO fabric was increased from 18.5 % to 36.7 % and the damaged length was reduced from 30.0 cm to 5.6 cm during the vertical burning test. The flame retardancy of PTau-NYCO fabric was well preserved with the LOI value of 29.2 % after 40 laundering cycles.
Cone calorimeter test indicated that the PTau-NYCO fabric decreased the peak heat release rate from 207.7 kW/m2 to 77.5 kW/m2, and the total heat release rate from 10.5 MJ/m2 to 5.6 MJ/m2, respectively, compared with that of the control NYCO fabric. The flame retardant mechanism showed that PTau was beneficial to form the char layer and generate nonflammable gases. In general, the work proposes a feasible method to produce durable flame retardant NYCO fabrics by using taurine derivatives.
The study has been published in Progress in Organic Coatings, Volume 171, October 2022.