户外用蜡浸注木工艺及物理力学性能

为提高木材在户外应用性能,采用性质稳定的高熔点聚乙烯合成蜡对户外常用木材进行高压浸注处理,研究了蜡浸注木材的物理力学性能。结果表明:蜡处于熔融状态时性质稳定、黏度小、流动性好,在压力下易渗入木材孔隙;木材蜡渗透性是蜡浸注量的决定性因素,樟子松和辐射松木材蜡渗透性较好,欧洲云杉和白云杉较差,柳叶桉居中;浸注蜡可使木材硬度、弹性模量略有提高,使木材横纹抗拉强度、抗弯强度和吸水性显著降低;采用3阶段浸注工艺可使樟子松和辐射松木材全截面含蜡,含蜡量分别为40.21%和41.45%;樟子松和辐射松蜡浸注木抗冻融性能及抗紫外光老化性较好,可应用于户外木结构工程。

Impregnating technology and physical mechanics properties of wax impregnated wood for outdoor use

In order to improve the performance of wood in outdoor application, polyethylene wax with high melting point was used for high pressure impregnation treatment to common wood and the physical and mechanical properties of wax impregnated wood were measured. The results showed that the wax in the molten state was stable with low viscosity, good fluidity, and penetrable into pore of wood under pressure. Wood permeability was the decisive factor of wax impregnation. In terms of permeability, Pinus sylvestris and Pinups radiata wood were outstanding, Eucalyptus saligna wood was moderate, Picea abies wood and Picea glauca wood were weak. Impregnating was help to slightly increase the hardness, the modulus of elasticity and water absorption but significantly decrease bending strength and tensile strength. The three stage impregnation process can make whole section of Pinups sylvestris and Pinups radiata wood full of wax in a value of 40.21% and 41.45% respectively. Due to excellent resistance to freeze-thaw and UV aging, Pinus sylvestris and Pinups radiata wax impregnated wood were the applicable outdoor wood for structural engineering.