Compressive Properties of Sawdust Composites Consisting of Sodium Silicate Solution and Corn Starch as Binder

Novel composite materials were manufactured using saw dust, sodium silicate solution and corn starch. Corn starch works as a reinforcement to the sodium silicate solution. The floatation method was utilized to obtain the wet mixture for manufacturing composites by compaction. The quantity of saw dust and sodium silicate solution were fixed and the starch powder content in the binder solution was the working variable. Starch powder content in the binder solution were 1.4 g, 1.6 g, 1.8 g and 2.0 g. The gelatinization of starch is investigated to confirm the gelatinized solid starch content in the binder solution. Compression tests were carried out on the composites in the Universal Testing Machine at a cross head speed of 1 mm/min. The density, compressive strength and modulus were found to increase with increasing gelatinized solid starch content. On the other hand specific compressive strength decreased with increasing density of the composite while specific compressive modulus showed an opposite trend. Comparing with the literature, the developed composites showed superior properties and were found to have practical applications.