Environmentally Safe Polymeric Wood Preservatives

Environmentally safe wood preservatives based on polybiguanides (PBGs) chemistry will be developed. Building on our preliminary data, the novel PBG molecular structure will be tailored to possess multiple functions (anti-fungal), insecticidal, ion-chelating and hydrophobicity) to perform as a broad spectrum wood preservative. Three molecular sites will be used to tailor the PBG molecule including: backbone, end-caps and associated anions. Total of 18 PBG compounds will be synthesized and tested using the standard soil-block method. The synthesis method is simple and versatile, and starting compounds are inexpensive. The main tasks include: synthesis of well-defined 18 structures, developed of methods for uniform compound penetration into wood, testing effectiveness as wood preservatives and analysis of data to define the most effective molecules for the Phase II study. Preliminary evaluations of our PBGs structures by Dr. Jeffrey Morrell identified two critical modifications leading to highly effective wood preservation performance, namely: chelation and hydrophobization. PBGs made with cystamine (a chelating segment) in the backbone and with hydrophobic character proved to be the most promising. These results constitute the foundation for the proposed 18 PBG structures. Only commercially available modifiers will be used to develop a cost-effective wood preservative.