modifying the bondability of rice husk/sodium silicate particleboard by using diisocyanate

in this study, rice husk and sodium silicate solution were used to produce particleboards. sodium silicate was used as bonding aid by 25, 20, 15, 10, 5 and zero percent (based on rice husk dry weight). to modify the mechanism of bondability, one percent of 4,4’-diphenylmethane diisocyanate (mdi) was added for every five percent less sodium silicate solution. the effect of diisocyanate on bondability was evaluated by measuring the bending strength, internal bond, thickness swelling and water absorption. data were statistically analyzed with spss software and comparison was made on the data obtained employing dancan test. generally the results have shown that increase in sodium silicate replacement with diisocyanate improves the mechanical and physical properties of particleboard. economically, the best condition obtained in this study was to use 15% sodium silicate solution with 2% diisocyanate to produce rice husk particleboard.