Non-Steady State Moisture Diffusion Flow in Homogenous Pineapple Leaves Particleboard

Abstract

Non steady state diffusion flow is unstable movement of moisture in a material which changes with respect to time. Diffusion coefficient describes the rate at which water moves from the interior to the surface of the materials. Absorption and desorption are the variables that are used to determine the diffusion coefficient. Understanding of the water absorption and desorption is important since it affects the mechanical properties of materials such as strength and durability properties. Water absorption and desorption of the materials or products intended for drying are important for the design and operation of dryers such as kiln drying and other processing system. Nowadays, the processing of solid wood into finish product is decreasing due to increase in the cost of solid wood and insufficient supply of quality logs. Agricultural waste such as pineapple leaves is one of the potential raw materials that can be used in particleboards manufacturing. Pineapple leaves particleboards were produced and the diffusion of coefficient of water absorption, percentage thickness swelling and percentage thickness shrinking were determined. Diffusion coefficient was determined based on the absorption and desorption rate. The particleboards manufacturing followed BS EN 326 and testing of samples was in accordance with BS EN 317. The difference in thickness of particleboard has great influence on physical properties. In this study the particleboard made of 1 cm has the lowest water absorption compared with 2 cm particle board and has highest thickness shrinking.