To improve the hydrophobicity of wood, utilizing a silica/wax composite emulsion (PPW@SiO2), which was prepared by maleic anhydride-grafted polypropylene wax (PPW) and nanosilica, served as a hydrophobic agent. The hydrophobicity modifying process of fast-growing poplar was carried out by heating permeation and hot pressing to prepare in-depth hydrophobic wood. The results show that the hydrophobic agent can fill the pores of poplar partly and form a two-dimensional, “petal-like”, rough hydrophobic structure in the pores. The water contact angle (WCA) on the surface of modified poplar can reach 140.3° when the amount of SiO2 is 1%. Even after surface grinding of 3 mm, the WCA is still higher than 130°, indicating the hydrophobic wood has a good performance of in-depth hydrophobicity. Furthermore, the surface of hydrophobic wood presents an exceptional self-cleaning function, and the physical and mechanical properties are also improved. Compared with a reference sample, the density, surface hardness, modulus of elasticity, compressive strength, and modulus of rupture of hydrophobic wood are increased by 66.67%, 53.16%, 55.60%, 49.50%, and 40.87%, respectively, and the water absorption in hydrophobic wood is also significantly decreased.

中文翻译：

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二氧化硅/蜡复合乳液结合热处理改性深度疏水木材的制备与性能

为了提高木材的疏水性，利用由马来酸酐接枝聚丙烯蜡（PPW）和纳米二氧化硅制备的二氧化硅/蜡复合乳液（PPW@SiO2）作为疏水剂。速生杨树疏水改性工艺通过加热渗透和热压制备深疏水木材。结果表明，疏水剂可以部分填充杨树的孔隙，并在孔隙中形成二维、“花瓣状”的粗糙疏水结构。当SiO2含量为1%时，改性杨树表面的水接触角(WCA)可达140.3°。即使表面研磨3mm后，WCA仍高于130°，说明疏水木材具有良好的深度疏水性能。此外，疏水性木材表面呈现出超凡的自洁功能，物理机械性能也得到改善。与参比样品相比，疏水木材的密度、表面硬度、弹性模量、抗压强度和断裂模量分别增加了66.67%、53.16%、55.60%、49.50%和40.87%，水在疏水性木材中的吸收也显着降低。