Effect of pretreatment and compaction ratio on the properties of oriented strand board from sengon (Paraserianthes falcataria L. Nielsen) wood

Abstract

ABSTRACT Low-density wood produces composites with low dimensional stability, requiring a high compaction ratio (CR) to produce an oriented strand board (OSB). This study evaluates the physical and mechanical properties of the OSB prepared from low-density wood, i.e. sengon (Paraserianthes falcataria L. Nielsen), under steam modification and various CRs. The wood strands were steamed at 126°C under 0.14 MPa pressure for an hour and then washed with 1% sodium hydroxide for 30 sec. Three-layered OSBs with a shelling ratio (face-to-core layers ratio) of 1:2:1 were manufactured using 10% resin content of phenol formaldehyde. Panels with three different strand pretreatments and five levels of CR were evaluated. The results show that there is an improvement in the bonding between the strand and the resin with steam and the steam followed by washing with 1% NaOH pretreatments. Both pretreatments of strands significantly improved the dimensional stability of obtained OSB but did not affect the mechanical properties. The physical and mechanical properties of OSB improved by the increased CR. The OSBs with a CR of 1.58 has the best physical and mechanical properties.