摘要

In this paper, an antioxidant composite was prepared using chitosan as the main material. Chitosan was modified by natural aromatic amine compound via grafting reaction and then blended with nanocellulose with higher aspect ratio, forming a new composite material. The structure of the polymer was characterized by FT-IR, 13C NMR and elemental analysis, which proved the success of adenine grafting. The antioxidant test results show that the obtained composite showed much higher strength than both chitosan and cellulose. Antioxidant evaluation also showed that the antioxidant activity of chitosan-based material significantly improved DPPH scavenging capability. The DPPH radical scavenging activity of MCBC membrane can reach 72.20%. And the doping of nanocellulose further increased its mechanical properties and dimensional stability. The tensile strength of MCBC-CNF-2 membrane reached 65.06 MPa, and the water absorption and swelling ratio were only 36.20% and 6.06%, respectively. Although the antioxidant activity of the modified chitosan membrane decreased with the increase of nanocellulose doping amount, the DPPH radical scavenging activity of MCBC-CNF-2 membrane still reached 54.20%. This obtained composite material was biodegradable and cost-effective, which is expected to be applied to food packaging materials.