Effect of Resin and Wax Ratio on OSB Properties

Oriented Strandboard (OSB) was made for construction purpose. Mat structure especially resin and wax ratio had an influence on major panel properties such as bending strength properties, stiffness properties, internal bonding, water absorption, thickness swell and so on. Thickness swell was an important property of OSB for using in construction and outdoor facilities. The purpose of this study was to investigate the effects of resin and wax ratio on OSB properties and rapidly predict OSB properties using near infrared spectroscopy. The laboratory OSB panels were fabricated as a multiple layer (three layers) mat structure including, orientation, resin types (phenol formaldehyde (PF) and polymeric methylene diphenyl diisocyanate (pMDI)), resin ratio (surface resin content/core resin content), and wax ratio (surface wax content/core wax content). The NIR data were collected from specimen at the wavelength between 350 to 2500 nm. Both principal component analysis (PCA) and partial least square analysis (PLS) were used to analyze the data. Increase of resin ratio can improve MOR and MOE especially in parallel direction including TS of laboratory made OSB. Increase of wax ratio can improve MOR, MOE, IB and TS in OSB with PF as core resin. However, decrease of wax ratio can improve MOR, MOE and IB.