| Abstract: | In the Federal Republic of Germany increasing attention is paid to the possibilities of using midi- and minirotation poplar wood as raw material for wood-based panels. In the article a brief account is given on the state of knowledge regarding the behaviour of poplar wood in particleboard manufacture. Debarked poplar chips are easily bondable with conventionel organic and inorganic binders. The use of a high amount of bark is deleterious to the physical-mechanical properties of boards, however, bark decreases the formaldehyde release of wood-based panels significantly. Due to its low density, poplar wood can be used for the production of high strength particleboards at low density level. The paper shows that no comprehensive data is available on the behaviour of tension wood towards bonding. Moreover, no detailed information is accessible on the gluability of juvenile wood. In the paper experimental results are reported concerning the properties of particleboards from 5-year old balsam poplar trees using UF- and PF-resins as binders. The results indicate clearly that there are no significant differences in the bonding strength between different clones. Using UF-resins boards with acceptable quality can be made from chips containing about 25% bark. The PF-bonded boards showed acceptable dry bonding strength. However, the wet strength was fast above or fast below the value required by the standard. |
