a b s t r a c t
Binderless boards were manufactured from rice straw by hot-pressing in order to evaluate the morphological
effect of particles from rice straw. For the morphological effect, we examined the influence of
particle size and morphological parts of rice straw, respectively. Internal bonding (IB), thickness swelling
(TS) and water absorption (WA) were measured as the properties of the boards. As a result, binderless
boards were successfully manufactured from rice straw powder smaller than 1mm. Regarding the effect
of morphological part from rice straw, IB of the board made from stem powder was the highest, subsequently
followed by leaf blade powder, and leaf sheath powder. IB tended to increase with decreasing
ash and silica contents. Trichomes and wart-like protuberances on the epidermis of rice straw might
inhibit the bonding between particles. The water resistance of binderless boards made from rice straw
was high regardless of low IB. It is possible that wax-like substances on the epidermis of rice straw might
contribute to the water resistance of the board.