Advances in wood protection based on nanotechnology can improve resistance of wood products to biodeterioration, reduce environmental impacts from chemical leaching, and resist ultra-violet (UV) light degradation of in-service wood.
Carol Clausen, a supervisory research microbiologist at FPL, has explored a number of different approaches to these issues and recently presented her findings in a paper called Innovations in Wood Protection in the Age of Nanotechnology at the 8th Latin American Biodeterioration and Biodegradation Symposium.
Clausen evaluated the nanometals zinc oxide (nanoZnO) and copper oxide (nanoCuO) as preservative treatments for wood. Both nanoZnO and nanoCuO were leach resistant while NanoZnO also inhibited decay fungi, acted as a termite toxicant, and provided photostability of wood against UV degradation.
Self-assembling nanopolymers were also soaked with an organic biocide. Common biocides include pesticides and antimicrobial materials. Clausen found that the porous surface of the nanopolymer surrounded and held the biocide until a change in the physical environment, such as elevated temperature, triggered its release.
Clausen also evaluated a nanocarrier system that used inert or nonreactive nanotubules loaded with organic biocides for targeted delivery and slow, controlled release of the biocide. This “nanoentrapment” assessed the ability of cellulose (wood) nanocrystals to chemically combine with and entrap water-soluble biocides within the wood structure without modifying the wood’s basic structural components.