Influence of Impregnation on Material Properties

Impregnation of wood may be effected by applying the polymer composition onto the wood surface with a brush, by spraying, or by dipping of a wooden item into the composition. The degree of impregnation depends on the type of wood, its quality, the time of contact of the wood and composition, and the composition curing speed. 

Water absorption. Before impregnation specimens were dried to constant mass. Tests showed that water absorption of impregnated specimens was zero, and check samples were characterized by 4.5-4.7% water absorption. 

Radiation stability. Radiation stability was checked by exposing impregnated specimens to 7-radiation from a °Co source. Tests showed that variants 1 and 2 are the most radiation-stable compositions. At doses of less than 120Mrad, no change was observed in the properties of the impregnated specimens. 

Chemical stability. Chemical stability was determined by immersing the impregnated specimens in various chemicals. At 6 and 12 months after exposure in different media, specimens were removed, dried, and subjected to compression tests. The tests indicated that impregnated specimens are stable to the action of solutions of salts, acids, and alkalis and imstable to the action of concentrated nitric, sulfuric, md hydrochloric adds. The most chemically stable is the acrylic composition. 

Permeability to chloride ions. Of various chemicsds, concretes come into contact with chloride-containing salts the most often, especially in places where streets are cleaned of snow with the help of salts. This leads to intensive deterioration of the concrete elements of roads and imdergroimd service lines. 

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