By introducing bulk vinyl polymers into the void spaces in wood, compression strength, hardness, and abrasion resistance are greatly improved. The diffusion of water moisture in and out of the wood-polymer materials is restricted. New treatments react monomers that penetrate the cell wall with the hydroxyl groups to greatly improve dimensional stability. A combination of treatments -- solid polymer in the void spaces and reactions with the cellulose in the cell walls-further improves the wood properties. Toxic groups can be attached to the polymers in the wood to give it built-in decay resistance. -- AATA