Vibrational properties of wood-plastic combination of sitka spruce impregnated with MMA/HEMA
1990
Sakano, N. (Tokyo Univ. (Japan). Faculty of Agriculture) | Okano, T. | Ota, M.
Changes in acoustical properties of Sitka spruce due to MMA/HEMA copolymer impregnation were investigated. The properties were evaluated by the dynamic Young's modulus E', dynamic shear modulus G' and internal loss Q(-1) measured using the flexural vibration method on free-free beams for the longitudinal and radial direction. In both the directions, E', G' and Q(01) showed tendency to increase with increasing polymer loading, except for G' in R-T plane reducing at lower polymer loading. Specific dynamic Young's modulus in the longitudinal direction decreased with increasing polymer loading. But in the radial direction, it increased in some range of polymer loading. In both the directions, the rate of increase in E' was higher than that in G'. As a result, the value of E'/G', which is the parameter exerting influence on frequency dependence of apparent Young's modulus or internal loss, became higher
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