Tannin bio-copolymers as wood preservatives

In the last decade several restrictions were applied in wood preservation especially for outdoor applications. The need of finding alternative solutions to creosote and heavy-metal based products is becoming a priority, but no performing solutions have been found yet. In this context, the idea of using tannins is an example of biomimetic, cradle-tocradle concept because these natural polyphenols are already used by the trees to protect themselves against biological decay. In this work the latest developments about the use of tannin bio-copolymers as wood preservative is presented and, in particular, two approaches are considered to overcome the rigidity problem presented by the classic tannin-based formulations: The chemical and the physical one. Both approaches showed improved leachability and when the formulations were added of small amount of inorganic biocides they resulted efficient against Coriolus versicolor producing a set of new interesting wood preservatives.