Dielectric, magnetic, and mechanical properties of composites consisting of biopolymer chitosan matrix and hybrid spinel/cellulose filler

The composites consisting of a biopolymer chitosan matrix and hybrid spinel/cellulose filler were prepared by solvent casting method whereas the spinel CoFe2O4 was obtained by mechanical synthesis followed by thermal annealing. Incorporation of cellulose to the spinel - chitosan composite significantly modified dielectric, magnetic and mechanical properties of a composite consisting of the biopolymer with hybrid filler. In dielectric response the presence of the filler in the chitosan matrix hindered the molecular motion. The lowering of the activation energy and the cooperativity of the motion was observed. According to the magnetic properties, addition of cellulose to the filler enhanced coercivity field H-c in comparison to the pure spinel powder from value 0.1453 to 0.2033 T. In mechanical properties incorporation of the filler resulted in improvement of Young's modulus and tensile strength in comparison to unfilled chitosan. For composites with nanocellulose filler tensile strength was over two times higher than for chitosan.