Flame-retardant thermoplastics derived from plant cell wall polymers by single ionic liquid substitution

Three components of plant cell walls-cellulose, hemicellulose and lignin-were converted into flame-retardant thermoplastics by adducting only a single ionic liquid species via covalent bonds. They showed thermoplasticity and formed thin films by hot pressing. They also showed flame retardancy and self-extinguished the fire during burning. The properties of the samples depend on the cation species of ionic liquids adducted and thus are controllable. In the present study, more than 66% of the hydroxyl groups present on the polymers were maintained after derivatisation; they thus have the potential for further functionalisation for moulding, practical use and so on, in addition to flame retardancy and thermoplasticity.