Thermoplastic Matrices and CNR-Based Systems

The possibility to combine different reinforcement phases in a polymer matrix was also recently considered in order to obtain multifunctional systems with increased mechanical and thermal properties providing also an antimicrobial response. In a recently accepted paper [160] Fortunati et al. demonstrated the high potential benefits offered by nanotechnology in the development of tailor-made nanobiocomposites with specific applications by the combination of two different synthesized nanostructures inorganic nanoparticles and cellulose nanocrystals in a biodegradable polymer matrix. 

Recently, researchers have shown an increased interest in carbon-based particles/cellu-lose formulation development, in which carbon particles are used to enhance mechanical properties and electrical conductivity simultaneously [168]. Regenerated cellulose/ graphene composite films had been recently prepared by dispersing graphene into cellulose solution and then casting the solution onto glass [169]. Graphene, the two nano-dimensional counterpart of carbon nanotube, consists of one atom-thick layer of 

A similar approach was also considered by Valentini et at [171] that successfully prepared homogeneous and conductive cellulose nanocrystals/graphene oxide (GO) composite films. The authors proved how the application of an electric current through the composite leads to the formation of a conductive NCC/GO film highlighting many exciting functional properties of graphene-based nanocellulose composites. 

Recently, the composite materials made of organic and inorganic phases have attracted much attention polymer-based composite materials have been widely used in the biomedical field [173], and natural polymers, such as cellulose, chitin, corn protein, starch and soy protein isolate (SPI) [174] have become important due to the increasing requirements for materials with characteristics of renewability, biocompatibility, biodegradability, and non-toxicity. 

The principal inorganic constituent of bone, hydroxyapaptite (HAP) is mainly used in the tissue engineering field due to its excellent biocompatible, bioactive, non-inflam-matory, nontoxic and osteoconductive properties [175]. It is noted that the incorporation of HAP into poly (1-lactide) can greatly improve protein adsorption capacity. 

---