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The objectives of this study were to detennine the influence of wood density on the physical and mechanical properties of commercial hard boards, as well as the acoustical property of the insulation board. The commercial fiberboard was manufactured under the same conditions as in Babolsar- and Iran- fiber companies.
It was found that the sound absorption of insulation board containing 95% low density wood fibers were 1.7-5.6 times higher than that of insulation board which contained 95% high density wood fibers.
The mechanical properties (static bending and tensile strength perpendicular to the surface) of
hardboard containing 95% high density wood fiber were 1.4-1.7 times higher. Water absorption was 7.3 and thickness swelling was 0.8 times higher than that for panels made of 95% low density wood fibers. Therefore, low and high density wood species are recommended to be utilized in insulation¬board and in hard- board manufacturing, respectively.