A new type of biocide suitable for use in different fields of wood preservation
V Barth, H Härtner
A new type of polymeric biocides was developed containing quaternary ammonium and boron ester groups as active structure elements, to overcome the disadvantages of AAC's in wood preservation use and to utilise their good performance due to a broad efficacy against fungi on the other hand. The new biocides called polymeric betains have been tested in laboratory and field tests and especially the didecyl substituted compound shows excellent efficacy against wood destroying and wood discolouring fungi (blue stain) and mould and against wood destroying insects including termites. The polymeric structure acts as a carrier for the quaternal ammonium salt causing excellent penetration properties and uniform dispersion in comparison with common AAC's. Fixation occurs by reaction in the pH-range of wood. For combination of polymeric betain with copper salts we found synergism against Basidiomycctes and Termites and good performance as ground contact treatment.