Unlike wood-based cellulose, bacterial cellulose has higher purity, crystallinity and is free of other contaminating polysaccharides and its isolation and purification are relatively straight forward, requiring minimum energy or chemical inputs. Bacterial cellulose production is a promising alternative for utilizing the unused carbon streams in the biorefinery processes contributing to added-value products. Typically, bacterial cellulose is generated at the air-liquid interface of the culture medium and forms pellicles with a randomly oriented fibrous network structure. By using the bioprocess engineering approach, we have successfully developed bacterial cellulose with different morphologies (BC sphere and BC tubing) and fiber orientation (BC alignment). These novel bacterial cellulose materials have already demonstrated great potential in many fields such as biomedical, wearable sensor, flexible/printable electronic devices, biocomposites, to name only a few.

Nanocellulose Bioinspired Assembling

In order to improve profitability, traditional forest products companies must diversify their product portfolios, and one promising new product is nanocellulose. For better utilization and probably amplification of nanocellulose mechanical property, it is crucial to gain control over the molecular forces and the physicochemical phenomena involved in its 3-dimensional assembling processes. Lessons can be learned from Nature, where a wide range of composite materials with outstanding mechanical properties (e.g. nacro, bone, tendon, and plant cell wall) were achieved with the well-arranged stiff fibers/particles at the nanoscale. Since nanocellulose exhibits anisotropic mechanical properties (the elastic moduli in the long axis of the fibers is much higher than in the transverse directions), it would be essential to induce a fiber alignment during the assembling process to maximize its mechanical property. We have been using wet-spinning and wrinkling processes to assemble/align nanocellulose into super-strong functional material for various applications.