Impregnability of Paulownia and Populus Wood with Copper Based Preservatives

The importance of fast growing wood species such as Paulownia and Populus wood is increasing. Unfortunately, these wood species do not have durable wood, so they have to be protected for use in outdoor applications. One of the most important groups of wood preservatives for heavy duty applications is the copper based one. Paulownia and Populus wood samples were thus treated with copper-ethanolamine (Cu/MEA) and acid copper chromate (ACC) according to various treatment processes: Bethell, Rüping and dipping. The dipping treatment was performed with various submersion times, ranging from 1 min to 10 days. The uptake of preservative solution, penetration and colour of the specimens were then determined. The results clearly indicate that the permeability of Paulownia is not as good as that of Populus wood. The permeability of Paulownia can be improved with the proper selection of impregnation procedure and wood preservatives. Cu/MEA was found to be more suitable for treatment of Paulownia wood than classical ACC.Važnost brzorastućih vrsta drveća kao što su paulovnija (Paulownia) i topola (Populus) svakim danom postaje sve veća. Nažalost, drvo tih vrsta nije baš trajno, stoga se prije uporabe u vanjskim uvjetima mora zaštititi. Jedna od najvažnijih skupina sredstava za zaštitu drva za uporabu u nepovoljnim uvjetima jesu ona na bazi bakra. Uzorci drva paulovnije i topole tretirani su bakar-etanolaminom (Cu/MEA) i acetatnim bakrenim kromatom (ACC) različitim postupcima obrade: Bethellovim, Rüpingovim i potapanjem. Postupak je proveden uz različita vremena uranjanja, u rasponu od 1 min do 10 dana. Tijekom eksperimenta određivana je količina upijene otopine zaštitnog sredstva, dubina njezine penetracija i boja uzoraka. Rezultati jasno pokazuju da permeabilnost paulovnije nije baš dobra kao permeabilnost drva topole. Permeabilnost paulovnije može se poboljšati pravilnim izborom postupka impregnacije i zaštitnog sredstva. Istraživanje je potvrdilo da je Cu/MEA prikladniji za zaštitu drva paulovnije od klasičnoga ACC-a