Submitted to: Association for the Advancement of Industrial Crops Conference
Publication Type: Abstract only
Publication Acceptance Date: 10/10/2003
Publication Date: 10/15/2003
Citation: NAKAYAMA, F.S., CHOW, P., VINYARD, S.H., DE[[E, N.A., FABER, A.L. TERMITE RESISTANCE OF KENAF COMPOSITION BOARDS TREATED WITH GUAYULE RESIN. ASSOCIATION FOR THE ADVANCEMENT OF INDUSTRIAL CROPS CONFERENCE. 2003. Interpretive Summary:
Technical Abstract: Composition boards resistant to insect damage are a desirable feature for their use in industrial and home construction. Such material should greatly reduce the costly replacement of termite-damaged wood and insure the structural integrity of the building. Acceptance of such products would be further enhanced by using raw materials that are cheap and environmentall acceptable. We propose to combine fibers from kenaf (Hibiscus cannabinus L.) and resinous material of guayule (Parthenium argentatum Gray), both of which can be considered as secondary products from the primary ones, i.e., paper from kenaf and latex from guayule. Thus, the objective of this investigation was to fabricate termite-resistance, medium density kenaf composition boards. Kenaf stalks consisting of four different cultivars were used to make the boards. 'Flake-board' was made by cutting the stalks into 7.62-cm sections and flaking with a ring-flaker. The flaked material was dried (8 to 10% moisture content) and screened to remove the fines. Phenol formaldehyde (PF) thermosetting resin (7%) and was (2%) were mixed with the kenaf flakes and the fiberboard made using 6.0 MPA pressure at 185 degrees C for 4 min. Flake-boards with an average thickness of 11.1 mm and specific gravity of 0.70 were produced, 'Fiberboard" made from fiberized stalks that were steam pressurized in a single rotating disk and dried to 5% moisture content. The prepared stalk was mixed with 7% PF and 1% was and the board formed at 6.0 MPA pressure at 185 degrees C and 4 min press duration. Sections (2.54 x 2.54 cm square) of flake-board and fiberboard were treated with de-rubberized guayule resin in a treatment chamber. The chamber with the sample was first evacuated for 5 to 10 min and then the resin solution was introduced into the chamber to impregnate the blocks. Pressure in the chamber was maintained for 30 min at 690 kPa. After exposure, the excess resin was wiped off the treated blocks, and the blocks dried in a vacuum oven to remove the acetone carrier solvent. The resin-treated and untreated blocks were exposed to the Eastern termite (Reticulitermes spp.) follwing ASTM procedures. The resin-treated kenaf flake-boared and the fiberboard were found to be resistant to termite damage. Termite survival was zero after a 2-week exposure. A combination based on two new crops, kenaf and guayule, provided the means of producing medium-density flake-board and fiberboard that were resistant to termites. When the raw materials are considered as waste or by-product sources, the fabrication of termite-resistant, medium-density flake-board and fiberboard appears to be economically feasible. Also, the possibility exists of blending guayule bagasse that still contains the resin with kenaf fiber to produce higher density composition boards.