Fabrication and characterization of microfibrillated cellulose and collagen composite films

Microfibrillated cellulose (MFC)-collagen composite films were prepared with a dispersion of acid swollen collagen fibers and carboxylated MFC at different ratios in an alkaline homogenous system. The surface topographic results obtained from SEM analyses indicated that the MFC entangled uniformly with collagen in the film and formed a closely interwoven network to reinforce the film structure. However, the MFC addition decreased the smoothness and light transparency of the films due to the aggregation of MFC. Compared to the film prepared with pure collagen, the hybrid composite film showed a higher strength and Young's modulus but lower elongation. The swelling of the composite film in water increased with the increase of the MFC ratio in the film matrix. DSC and TG analyses demonstrated that adding MFC to collagen benefited the thermal stability of the films, due to the conformational and crystal changes in the MFC/collagen structure indicated by the FT-IR and XRD results. The MFC/collagen composite film can potentially be used as an edible material in the food and packaging industry, in particular for meat products.