Characterization of sugar maple wood-polymer composites: Monomer retention and polymer retention

Abstract

Abstract In this study, sugar maple samples were impregnated with three impregnants by a vacuum and pressure process and in situ polymerized by a catalyst-thermal procedure. The effects of polymeric monomers and their combinations on monomer retention by volume (MRV) and weight (MRW) and polymer retention (PR) were analyzed and the wood was examined by scanning electronic microscopy (SEM). The three methacrylates chosen as impregnants were methyl methacrylate (MMA), hydroxyethylene methacrylate (HEMA) and ethylene glycol dimethacrylate (EGDMA). The formulation combinations were determined by a mixture design. MRV was similar, regardless of formulation combinations, which indicated that these methacrylates show similar permeability into sugar maple. However, MRW was different between formulation combinations due to differences in monomer density. MRV was inversely related to wood density. PR was related to the combination of impregnants and inversely related to wood density. The impregnants resided in the vessel and the lumen. The morphology of polymers in the wood was different for different treatments due to the distinct molecular structures formed from each polymer.