Investigation of the Effect of Organoclay Additives on Mechanical Properties of PF resin and MPB-OSL using Creep Behavior Analysis and IB Test

Abstract

ABSTRACT The effect of organoclays on the mechanical properties of cured phenol formaldehyde resin and oriented strand lumber made from Mountain Pine Beetle killed pine strands was analyzed. Three organoclays were used: a natural montmorillonite, hydrophobic organically modified 10 A, and hydrophilic organically modi-fied 30 B. The oriented strand lumber samples were less creep deformation as well as improved internal bonding strength by adding organoclays in the order of 10 A 2% > MMT 2% > 30 B 2% > control. Furthermore, time-temperature superposition (TTS) analysis was proved to be able to predict the long-term creep behavior of MPB-OSL samples. Keywords : creep behavior, organoclay, internal bonding, MPB-killed pine, oriented strand lumber (OSL), time-temperature superposition (TTS) 1. INTRODUCTION Lodgepole pine (Pinus contorta) is a major wood species used to produce wood composites in Western Canada. However, approximately 4.2 million hectares of the total 8 million hec-tares of mature lodgepole pine in the central in-terior of British Columbia has been infested by the Mountain Pine Beetle (MPB, Dendroctonus ponderosae Hopkins) (Morford et al., 2004; Natural Resource Canada, 2004). To maximize the value from the pine forests, most forest product companies in the province have been harvesting green timber. This will inevitably re-sult in an enormous amount of MPB infested wood, potentially not suitable for traditional wood products. However, the large amount of MPB infested wood could be utilized for wood composite products, one possible end-use being oriented strand lumber (MPB-OSL) (Feng et al., 2007; Oudjehane et al., 2008∼2009).Recently, nano-fillers have been receiving significant attention due to their ability to im-prove mechanical properties and thermal stabil-ity of composite materials (Pinnavaia et al., 2000; Lei et al., 2006; Lin et al., 2005; Lei et al., 2007) Organoclay/polymer composites have exhibited dramatic increases in strength, barrier