Abstract
This study was put to investigate the possibility of utilizing E. camaldulensis bark extract as an adhesive for particleboards manufacturing after the determination of their tannins content. Bark extracts were extracted by using either hot water or 1% Na2CO3 (both gave an acceptable percent of extracted tannin). Prior to panels manufacturing, the concentrated extracts were hydroxymethylated with para-formaldehyde which normally releases formaldehyde during hot pressing. Panels were manufactured using either hydroxymethylated hot water extract or hydroxymethylated Na2CO3 extract, all at three levels of pressing temperature (160, 175, 190 c◦.) and two levels of pressing time (10 and 15 minute). A 10% resin content was used to get a panels target density of 0.55 gm/cm3. The physical and mechanical properties of the produced panels were tested. The results indicated, that by using hot water hydroxymethylated extract, a better values of the different studied properties were obtained, especially with those panels which manufactured at 175c◦.press temperature and 15 minute pressing time, but in general the average values of such panels did not exceed the values of the same properties given in the American standard for particleboards properties.
