The improvement of Brinell hardness of sugar maple (Acer saccharum Marsh.) samples through impregnation and in-situ polymerization of methyl methacrylate, 2-hydroxylethyl methacrylate, and ethylene glycol dimethacrylate monomers was investigated. The formulation combinations were determined by a mixture design. Sugar maple samples were impregnated with these mixtures by a vacuum and pressure process and polymerized in situ by a catalyst-thermal procedure. The effects of the monomers and their combinations on Brinell hardness and hardness modulus were analyzed. Chemical impregnation enhanced both Brinell hardness and hardness modulus. A significant relationship between hardness modulus and Brinell hardness was found. Modulus of elasticity of sugar maple was also improved through impregnation with methacrylates. (c) 2005 Wiley Periodicals, Inc.