抄録
Wood-based boards were manufactured under heat and pressure using softwood powder of #100 in size as furnish bonded by a novolac type of phenol-formaldehyde powder resin. The bending properties, internal bond strength and dimensional stability were determined to evaluate the effects of the specific gravity (SG), resin content (RC) of the board and platen temperature at pressing. The results obtained were summarized as follows:
(1) After a rapid temperature rise during pressing, the core temperature of the mat showed the plateau stage around 140°C for all the press conditions in this experiment ranged from 160°C to 220°C. (2) The bending properties, modulus of rupture and modulus of elasticity increased linearly with increasing resin content up to about 20% and leveled off above 30% RC. A linear relationship was found between bending properties and SG of the board. (3) It was found that the boards made from the wood powder can have higher internal bond strength compared with that of particleboards. (4) The boards with 15% resin content or more showed a fairly good dimensional stability against the water soaking treatment.
