Date of Award

5-2014

Level of Access Assigned by Author

Campus-Only Dissertation

Degree Name

Doctor of Philosophy (PhD)

Department

Forest Resources

Advisor

Douglas J. Gardner

Second Committee Member

Stephan M. Shaler

Third Committee Member

David J. Neivandt

Abstract

Bacterial cellulose (BC) nanofibers have received considerable attention as a source of nanometer-sized fillers because of their ultra-fine nano-sized three-dimensional fibrous network structure, high purity and high crystallinity, large water holding capacity, excellent biodegrability and biological affinity and high mechanical properties. Because of its unique properties, BC appears to be an interesting potential candidate for the development of new materials for high technology applications. In spite of its extensive applications in the medical and food industries (Nata de coco), the potential for BC in reinforcing polymers is not very well known for highly technological applications such as transparent nanocomposites and electrically conductive papers.

This research addresses a new approach and provides a potentially economical process for the production of BC from hot water wood extractives, providing a potentially low-cost, environmentally-friendly nanomaterial for advanced applications on a large scale in static conditions from the bacterial species, Acetobacter xylinus 23769. This research also addresses an alternate approach for producing bacterial cellulose in the presence of different nanoscale particulates for use in manufacturing reinforced nanocomposites. One of the most attractive properties of bacterial cellulose is the ability to control and modify the physical characteristics of the cellulose product while it is being produced. This allows the producer to change the properties of the cellulose. In addition, by culturing BC in the presence of nanoscale particulates (exfoliated graphite nanoplatelets (xGnP), nanoclay and nanofibrillated cellulose (CNF)) in an appropriate culture medium, the BC is preferentially deposited in situ onto the surface of nanoscale particulates. Nanofiller embedded BC improves the mechanical and thermal properties of BC and also, expands application of BC into different areas. This study also examined the production of nanocomposites including: creation of transparent nanocomposites using PMMA and BC, and the production of electrically conductive polymer nanocomposites in the presence of xGnP.

Download

Share