BIOLOGICAL, PHYSICAL AND MECHANICAL-PROPERTIES OF PARTICLEBOARD MANUFACTURED FROM WASTE TEA LEAVES

Environmental questions have arisen from the use of chemicals in wood or bio-based composite to stop biodeterioration. As a consequence, var ious environmentally friendly treatments or naturally durable plant sp ecies are now being evaluated. We believed the high phenolic extractiv e content of tea leaves, and their abundance as residual waste at tea producing factories warranted studies on the utilization of these wast es in particleboard manufacture. Waste tea leaves particleboard (WTLB) is expected to be more resistant against biological agents owing to h igh phenolic extractive content. Mass loss of WTLB, the edges of which had been sealed with an epoxy, was 3.5-8.6% and 6.0-12.1% for paraffi n-added and non-added specimens, following degradation by Tyromyces pa lustris and Coriolus versicolor, respectively. The addition of paraffi n to binder UF resin during the manufacturing of the board and sealing the edges of specimens before decay testing kept degradation to a min imum. In reference materials reported previously, WTLB proved resistan t to decay-type fungi. Mass loss of WTLB after exposure to Formosan su bterranean termite Coptotermes formosanus was around 16%. However, ter mite mortality levels and trends over the three weeks of termite attac k suggest that phenolic extractives of tea leaf act as natural toxican ts that gradually but steadily increase mortality particularly from th e third week of exposure. Tested physical and mechanical properties of WTLB indicated that it performs as well as the general purpose boards designated in BS 5669. (C) 1998 Elsevier Science Ltd. All rights rese rved.