Accelerated thermal aging of bio-based composite wood panels

Abstract

Bio-based adhesives and resins are sought as alternatives to synthetics in order to fabricate all-biobased composite wood panels (CWPs), which provide environmentally friendly building products for indoor use. Very little information exists as to how these bio-based CWPs would perform long-term in non-temperature controlled structures such as warehouses and storage units where extreme temperatures occur depending on the season. In this study, novel all-bio-based CWPs were fabricated using a matrix of 50% distiller's dried grains with solubles (DDGS) and 50% soybean flour ProsanteTM (PRO) mixed with wood particles. Bio-based CWPs were subjected to accelerated thermal aging for a 10-year period resembling outdoor temperatures in Peoria, IL USA. Four seasonal periods (Winter, Spring, Summer, and Fall) were simulated varying from-26-40 °C and 36-76% relative humidity (RH). The bio-based adhesive employed consisted of 50% distiller's dried grains with solubles (DDGS) and 50% soybean flour ProsanteTM (PRO). CWPs consisted of 15 or 50% DDGS/PRO with 85% or 50% pine wood. CWPs were evaluated for 5, 7.5, and 10-years for their physical, flexural, dimensional stability, surface roughness, FTIR, TGA, and spectral properties. The changes in the CWP properties were notable during the initial 5 years, and later aged samples showed less change.