辐射松重组木密度对其孔隙率和性能的影响

为高值化利用人工林速生材辐射松Pinus radiata，采用高性能重组木制造技术，制备了不同密度的辐射松重组木，并探讨了密度对其孔隙率、耐水性以及力学强度的影响规律。结果表明:辐射松素材的孔隙率约为68.00%；重组木的孔隙率随密度增大呈线性下降，低至2.11%。随密度增大，重组木的耐水性和力学强度均呈升高趋势；当密度从0.80 g·cm-3增加到1.39 g·cm-3，吸水厚度膨胀率和吸水率分别下降了21.55%和76.88%，弹性模量和水平剪切强度分别提高了116.47%和86.29%。

Effect of density on porosity and physical-mechanical properties of high-performance scrimbers

For value-added utilization with fast-growing wood of Pinus radiata as well as promotion of added value of the products, outdoor scrimbers with varying densities were prepared with P. radiata as the raw material via the manufacturing technology of high-performance reconstituted wood. Then, effect of density on porosity, water resistance, and mechanical strength of the obtained scrimbers was determined. Results showed that the porosity of air-dry logs was 68.00%. Also, scrimber porosity decreased as density increased and the minimum was 2.11%. Both water resistance and mechanical strength were trengthened with an increase in density. When the density increased from 0.80 to 1.39 g·cm-3, thickness swelling rate (TSR) decreased 21.55% and water absorption rate (WAR) decreased 76.88%; whereas, modulus of rupture (MOR) increased 116.47% and horizontal shear strength (HSS_⊥) increased 86.29%. It suggested that the density of P. radiata scrimbers had a big impact on porosity and physical-mechanical properties.