| Popis: |
Rice straw was used as an alternative raw material to obtain cellulosic's pulps. Pulping was done by using classics reagents as soda (with anthraquinone and parabenzoquinone as additives), potassium hydroxide and Kraft process. The holocellulose, α-cellulose and lignin contents of rice straw (60.7, 41.2 and 21.9 wt%, respectively) are similar to those of some woody raw materials such as pine and eucalyptus, and various non-wood materials including olive tree pruning, wheat straw and sunflower stalks. In this paper, rice straw composite boards were manufactured as using the method used in the wood-based panel industry. The raw material, rice straw, was chosen because of its availability. The manufacturing parameters were: a specific pressure of 15, 20, 30,40, and 50 bar, and a rice straw content (15/100, 20/100, 30/70,40/100, and 50/100 by weight of UF/ rice straw) A commercial urea–formaldehyde adhesive was used as the composite binder. The composite boards made from a random cutting of rice straw. The experimental investigation indicated that the optimum particleboard properties are obtained with a mixture ratio of 350 gm UF(Urea-Formaldehyde), pressure 40 bar, 12 mm thickness, the bending modulus of rupture (MOR) of the rice straw composite is 240 kg/cm2 and a density of 1250 kg/m3.When the intended use of these particleboards is as wood panels. |
