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Wood Chemical Impregnation
The present invention relates to a method for preparing plastic impregnated wood, in which dry wood (moisture content below 10 percent) is impregnated with liquid resin material in a manner prior known per se e.g. the wood is put into a vacuum impregnation vessel, the air is evacuated, the vessel flushed with nitrogen, the liquid resin is introduced in the vessel until the wood is immersed, an atmospheric nitrogen pressure or an overpressure of 1 to 8 atmospheres gauge is applied. The wood is transferred into bags or containers filled with nitrogen, then hermetically sealed, then the impregnated wood is cured utilizing radioactive radiation optionally in the presence of chemical catalyst addition. The resin utilized for the wood impregnation contains commercial unsaturated polyester between 35 and 95 percent and styrene and/or methyl methacrylate. The amount of radiation is between 0.5 and 1.5 Mrad in the case of gamma radiation and between 1 and 5 Mrad if high energy electron radiation is used. As chemical catalyst is used an organic peroxide and the curing is carried out at a temperature between 40° and 60° C. utilizing as additives when necessary chemical inhibitors such as pinene in an amount of less than 5 percent.