Fire-retardant and ductile clay nanopaper biocomposites based on montmorrilonite in matrix of cellulose nanofibers and carboxymethyl cellulose

► Oriented nanocomposite based on clay in two-phase cellulose nanofibril/polymer matrix. ► Nanocellulose improves modulus, strength and strain to failure of clay nanocomposite. ► Nanocellulose is toughening agent, delaying failure events to higher strains.