MDI(methylene diphenyl diisocyanate) 樹脂를 利用한 톱밥보드의 物性(I)

The properties of sawdust board in using MDI(methylene diphenyl diisocyanate) resin(I): On the specific gravity , resin additive content and mat moisture content

This paper reports on the effects of mat moisture content(5%, 10%, 15%, and 20%, specific gravity(0.6, 0.7, 0.8, and 0.9), and resin(3%, 5%, 7%, and 9%) levels on physical and mechanical properties of MDI bonded- sawdust board. As mat moisture content increased, MOR and MOE increased and dimensional stability improved as a whole. Therefore, we considered that MDI resin can be used at high moisture content level(20%) without longer press time. As increasing of specific gravity, MOR, MOE and IE increased but water absorption and linear expansion decreased. Thickness swelling has no change with specific gravity levels. As increasing of resin level, MOR, MOE and IE increased linearly but thickness swelling and water absorption decreased. It was shown that in the case of sawdust board bonded with MDI resin, the same properties obtain approximately from a quarter level of urea formaldehyde resin added. The physical and mechanical properties of sawdust board bonded at MD I resin level of 7% or more were equivalent to those of conventional urea bonded particleboard. but, because of high price of MDI binder, the application of MDI resin to particleboard will be impossible to use with same level of sawdust board added at this study. Further research and development will focused on determining appropriate uses like as comply or molded products types in use of sawdust with MDI resin.