Preparation of bacterial cellulose/graphene nanosheets composite films with enhanced mechanical performances

•Bacterial cellulose (BC)-graphene composite films were successfully prepared.•The addition of graphene decreased the hydrophilic property.•BC-graphene composites exhibited enhanced thermal stability.•The addition of graphene plays important roles in the mechanical improvements.

Graphene has been considered to be a promising nanofiller material for building polymeric nanocomposites because it has large specific surface area and unique mechanical property. In the study, BC/graphene composites were prepared by a simple blending method. The resulting structure and thermal stability of the composites were investigated by several techniques including TEM, SEM, XRD, TG and Raman spectrum. These results indicate graphene nanosheets were successfully impregnated and uniformly dispersed in the BC matrix. Water contact angles result showed that the addition of graphene decreased hydrophilic property since water contact angle of BC increased from 51.2° to 84.3° with 4 wt% graphene added. The mechanical performances of BC/graphene composites were highly evaluated. When compared to pristine BC, the incorporation of 4 wt% graphene improved the tensile strength from 96 MPa to 155 MPa and Young's modulus from 369 MPa to 530 MPa, respectively.