Vacuum-pressure treatment of rubberwood (Hevea brasiliensis) using boron-based preservative

摘要

Rubberwood is highly susceptible to biodegrading organisms. To minimize this problem, effective preservative treatment needs to be carried out immediately to ensure that the timber is fully protected. Generally, a pressure treatment process would be adopted to force high preservative loading into the outer layer of the timber, followed by natural diffusion process of the preservative into the core area during seasoning. Apart from pressure intensity and pressure duration, timber sizes and concentration of preservatives used would largely influence the effectiveness of pressure impregnation process. In this study, four different thickness of rubberwood were selected viz. 25 x 25 mm, 50 x 50 mm, 75 x 75 mm and 100 x 100 mm, and 600 mm long. The samples were treated with 1, 2, 3 and 4 % w/w boron preservatives using the vacuum-pressure impregnation process. The determination of preservative loading in the wood samples was based on a modified method of Japanese Agriculture Standard for Plywood 1985 using Inductively Couple Plasma Spectrometry.