Polyvinyl acetate (PVAc) adhesives have become one of the most important adhesives in the woodworking industry. Commonly known as "white glue", this adhesive's many advantages include low cost, fast set, high dry bond strength, simplicity of application, and minimal harmful environmental effects. However, being thermoplastic and derived from a water-based emulsion, PVAc adhesive formulations have historically had some serious disadvantages including poor moisture and heat resistance.
Several different approaches have been taken to improve the moisture and heat resistance of PVAc wood adhesives, and these formulation modifications are the subject of this article. These approaches have been relatively successful and resulted in products that meet the European standards of non-structural wood adhesives (BS EN204). This article will first describe the general characteristics of PVAc emulsions and their adhesive formulations, and then specifically focus on advancements that have been made regarding the enhancement of moisture and heat resistance.