Rice-Husk Particle Boards with Bamboo Mat Veneer 250 nos. temporary shelters (20 ft x 12 ft x 8 ft high) are being built using rice-husk particle boards with bamboo mat veneer. These boards have been developed by M/s Padmavathy Panel Boards Ltd., Bangalore with the technology licensed by National Research & Development Corporation (NRDC), a Public Sector undertaking of the Ministry of Science & Technology. The product is eco-friendly & manufactured out of agro-waste products such as rice-husk & cashew nut shell liquid. The cleaned rice-husk is blended with phenolic resin & cashew nut shell oil to have a thin coat of resin on the surface. Predetermined quantity of coated rice-husk is spread as mat in hydraulic press and pressed to predetermined pressure and cured at elevated temperature. The bamboo mat is phenol bonded on the rice-husk boards to provide dimensional stability. The boards have been successfully field tested by constructing such temporary shelters for dormitories, go-downs, kiosks etc. Applications & Properties The rice-husk particle boards are manufactured in various densities, thickness, types and grades to suit a wide range of applications. Some of the applications are listed below : Wall Panelling Medium density rice-husk particle boards, both plain and overlaid with decorative laminates can be used as wall panels Doors, furniture, windows, table tops Plain and overlaid decorative medium density boards can be used instead of wood-based boards. These boards when used as the core for flush doors and window shutters ensure freedom from insect attack. False ceilings Tiles made of low-density boards make attractive false ceilings. Thermal insulation and sound absorption are added advantages Roofing panels Medium & high density boards make excellent pre-fabricated, light-weight roof panels for low cost housing, roof terrace houses, geodesic domes, garden houses, beach booths etc., because of their resistance to decay and fire retardance Insulation Low density boards can be used as thermal insulation material in air-conditioning, refrigeration Partitions and stage settings The low cost & fire resistance of these boards makes them suitable for partition and stage settings Industrial and domestic flooring High abrasion resistance make these boards ideally suited for floorings The rice-husk boards were tested as per IS-3087-1985 & IS-2380-1977 against the specified values. The properties of rice husk boards are given in the following table Sl. No. Tests Observed Value Specified Value 1. Density (Kg/m3) 640-870 500-900 2. Average moisture content (%) 8.0 5-15 3. Water absorption by weight (%) i) 2 hrs. soaking 4-13 25 ii) 24 hrs. soaking 12-35 50 4. Swelling (%) – 2 hrs. soaking i) thickness 4-6 10 ii) length 0.2-0.3 0.5 iii) width 0.2-0.3 0.5 5. Modulus of rupture min. upto 20 mm thick (N/mm2) 20.90-23.50 15.00 6. Tensile strength perpendicular to surface min. upto 20 mm thick (N/mm2) 3.40-3.62 0.45 7. Tensile strength perpendicular to surface (N/mm2) i) after cyclic test 0.30-0.33 0.20 ii) after accelerated water resistance test 2.86-2.93 0.15 8. Screw withdrawal strength (N) i) face 1616-1646 1250 ii) edge 1285-1312 850 Rice-husk particle boards have distinct advantages as compared to wood particle boards and other conventional boards as listed below : Termite resistance Rice-husk particle board being phenol formaldehyde bonded is termite resistant even when exposed to termites in a termite mound for years Decay resistance These boards are decay resistant when in contact with moisture in all forms. This property can be further improved by decay proof synthetic resin adhesive Fire resistance The naturally inherent fire resistance of rice-husk is further improved by compacting the husk to a high-density board. Rodent resistance High silicon content of rice-husk along with phenolic resin imparts rodent resistance to the boards
