Determination of free formaldehyde released in wood-based material

Koli~ina prostega formaldehida v lesnih proizvodih je kljub nizkim vrednostim {e vedno predmet stalnega nadzora in tudi predmet novih raziskav. Kljub {tevilnim razvitim in tudi uporabljenim metodam danes {e ne obstaja univerzalna metoda, s katero bi z najve~jo zanesljivostjo ugotovili koli~ino vsebovanega prostega formaldehida v lesnih proizvodih. V razli~nih de`elah so uporabljajo razli~ne standardizirane metode. Korelacije med nekaterimi od njih{e niso znane. V prispevku smo ugotavljali vsebnost postega formaldehida vivernih plo{~ah po perforatorski metodi, s ciljem dolo~itve korelacije med jodometri~no titracijo in acetilacetonsko metodo. Ker na koli~ino spo{~enega prostega formaldehida vpliva tudi struktura materiala, smo ugotavljali tudi vpliv sestave iverne plo{~e na koli~ino oddanega formaldehida. Korelacija med jodometri~no titracijo in acetilacetonsko metodo je dobra (R2= 0,8265). Sestava iverne plo{~e, pri ~emer smo se omejili na razmerje med srednjim in zunanjima slojema iverne plo{~e, vpliva na koli~ino oddanega formaldehida.The quantity of free formaldehyde in wood products in spite of low values is still the subject of constant supervision and also the subject of new investigations. Despite numerous methods developed and in use, there is, presently, still no universal method by means by which the quantity of free formaldehyde release in wood products can be established with certainty. In the various countries, various standardised methods are in use. The correlations among some of them are still unknown. In the article we determined the content of released free formaldehyde in particleboards according to the perforator method with the objective to determine the correlation between the iodimetric titration and acetylacetone method. Becausethe quantity of released formaldehyde is also affected by the structureof the material, we also tried to establish the influence of the composition of a chipboard on the quantity of released formaldehyde. The correlation between the iodimetric titration and acetylacetone method is good (R2 = 0.8265). The composition of a chipboard (where we limited ourselves to the ratio between the middle and external layers of the particleboard) has influence on the quantity of released formaldehyde