Abstract

In this study, dynamic mechanical analysis (DMA) was used to investigate the curing behavior and bonding performance of phenolic resins with different molecular weights as a function of three wood species. The curing process of the resin was characterized by both gel point and tanδ. The change in storage modulus before and after curing was used to characterize the bonding development. Resin molecular weight was found to significantly influence the curing process, while the effect of wood on the curing behavior among the three species was not clear. The resin should contain a low-molecular-weight fraction and a high-molecular-weight fraction to achieve the best bonding performance. The optimum molecular weight and molecular weight distribution was found to be different among the different wood species studied.