High heat resistance of adhesive bonds to wood and aluminum

Abstract

Wood is preferred as a building material due to its high strength, low weight, and ability to retain many of its properties even at moderately high temperatures. However, numerous wood adhesives lose strength as the temperature increases, especially around 200°C. This study examined bond strength at temperatures above that required for initiation of wood degradation for bonds of wood-to-wood and wood-to-aluminum using two oil-based adhesives (resole phenolics and epoxies) and two bio-based adhesives (soy protein isolate and ovalbumin from egg whites). The phenolics not only gave the best strength in the wood-to-wood bonding, but also in the wood-to-aluminum bonding. The second best were the protein adhesives, and the epoxies were the weakest. This research reinforces the use of phenolic adhesives for wood exposed to high temperatures.