Attapulgite modified cotton fabric and its flame retardancy

Flame-retardant treatment for cotton fabric has been raising considerable interest. However, flame-retardant treatments in many studies have drawbacks, such as releasing toxic gases, high cost and weak bonding to the matrix. In this paper, attapulgite clay (ATP) was treated by ball-milling, activation and double-bond modification. Cotton fabric was grafted to achieve mercapto functionalization. Finally, the flame-retardant cotton fabric was prepared by grafting ATP onto the surface of the cotton fabric via thiol–ene click reaction. The resultant cotton fabric showed outstanding flame-retardant properties. Its burning rate, limiting oxygen index and maximum smoke density were 5.3 mm/s, 25.6% and 14.27%, respectively. Compared with the original cotton fabric, the flame-retardant properties of the obtained cotton fabric were significantly improved. It was attributed to the as-formed more stable oxide layer decomposed by ATP during burning. Furthermore, the as-prepared flame-retardant cotton fabric did not cause any health hazards. This work is favorable for promoting the development of halogen- and phosphorus-free flame-retardant cotton fabric.