Physical and Mechanical Properties of Bamboo Oriented Strand Board Prepared fromAlkali-Immersed Strands

Abstract

In this work, the physical and mechanical properties of bamboo oriented strand board (BOSB) prepared from alkali-immersed strands were examined. The Dendrocalamus asper strands were modified with alkali treatment by immersing them in 1% sodium hydroxide solution for 1, 2, and 3 hours. Three-layers BOSBs (30 x 30 x 0.9 cm3) were prepared using phenol-formaldehyde (PF) adhesive of 8% concentration and 1% paraffin. According to JIS A 5908:2003 Standard, the physical and mechanical characteristics of BOSB were evaluated (JSA, 2003). The study showed that alkali treatment improved the dimensional stability of BOSB. Immersion in 1% sodium hydroxide solutions enhanced internal bonding (IB). The longer the immersion time, the better the WA, TS, and IB values. However, alkali treatment decreased the bending strength, i.e., modulus of elasticity (MOE) and modulus of rupture (MOR). The physical and mechanical properties of all BOSBs met the commercial standard, except the BOSBs prepared from strand with alkali immersion treatment by 1% sodium hydroxide solution for 3 hours. Alkali immersion treatment of D. asper strands for producing BOSB for 1-2 hours was still acceptable. The results could provide an alternative method to produce high-performance oriented strand board using bamboo as the raw materials.

Performance of Oriented Strand Board Made of Heat-Treated Bamboo (Dendrocalamus asper (Schult.) Backer) Strands

“…Fabrication of Bamboo Oriented Strand Boards (BOSBs) Figure 2 depicts the process of manufacturing an OSB utilizing bamboo strands. Laboratory BOSBs with dimensions 300 mm × 300 mm × 9 mm and a target density of 0.7 g cm −3 were manufactured, following the technical procedure described by Maulana et al [16]. Briefly, approximately 8% of PF resin mixed with 1% paraffin wax were sprayed onto the strands using a rotary blender.…”

“…Previous studies have explored different approaches for modifying bamboo strands, intended for producing BOSBs, including steam treatment [ 11 , 12 , 13 ], a combination of steam treatment with rinse by 1% NaOH [ 4 , 7 ], steam treatment and physical modification [ 4 , 14 , 15 ], alkaline immersion treatment [ 16 ], as well as post-heat treatment [ 9 , 17 ]. Post-heat treatment of BOSBs resulted in enhanced dimensional stability of the composites but decreased their mechanical properties, possibly related to the increased brittleness of the materials after thermal treatment [ 9 , 18 ].…”