Subsequently the dry, impregnated w

Subsequently the dry, impregnated wood flour was
ground in a mortar and then passed through a sieve with hole size
of 500 lm. Larger particles were ground and sieved repeatedly until all passed through the sieve. Adhesion forces were relatively
weak thus large particles could be crushed easily. The resulting
powder was used in the extraction/dissolution and water absorption experiments. Impregnated wood powder was dried in an air
circulation oven for 4 h at 105 C before composite preparation.
The efficiency of the impregnation process and the location of
the resin on or in wood particles were determined by extraction/
dissolution experiments. 25 g impregnated wood flour was put
into 500 ml distilled water and stirred at room temperature for different times. After the elapse of extraction time wood was filtered
out of the slurry, dried at 50 C and weighed. The difference between the initial and final weight was regarded as the extracted
amount of resin.