Department of Wood Science and Technology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva ulica 101, 1000, Ljubljana, Slovenia.
Center for Experimental Mechanics, Faculty of Mechanical Engineering, University of Ljubljana, Pot za Brdom 104, 1000, Ljubljana, Slovenia.
Sci Rep. 2023 Mar 1;13(1):3429. doi: 10.1038/s41598-023-30622-y.
The coatings on wood must sometimes give aesthetic and basic protection to wooden elements and prevent the development and transmission of microorganisms. Several polymers containing different nanoparticles have already been offered to day for this purpose. The research presents a novel poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP)/polyvinylpyrrolidone (PVP) polymer composite with MoO nanowires with the ability to form coating films on wood. The films of the developed coating exhibit elastic behaviour, which depends on the coating film thickness [tested wet film thicknesses (90, 180 and 360) µm]. The coating showed the ability to interact well with the surface of common beech (Fagus sylvatica L.) wood, in terms of wetting (contact angles of 15.6°), fast spilling on the surface, good penetration of the coating in wood structure and formation of up to 40 µm-thick films with excellent pull-off adhesion strength (6 MPa). An increased roughness of wood coated with C + MoO was a consequence of wood etching by the dimethylformamide solvent present in the coating. Moreover, the presence of C + MoO on wood made it considerably more hydrophobic, with contact angle of water raising to 123° from initially 46° measured on uncoated wood. The irradiation of wood surfaces with ultra-violet light resulted in visible colour changes on both uncoated and coated wood. The wood coated with C + MoO has a good resistance to water, alcohol and dry heat (grade 3 to 4). The antimicrobial testing showed that the presence of MoO in the coating plays an important role in the resistance of the coated wood to blue-stain fungi and mould development. The developed PVDF-HFP/PVP/MoO coating has an excellent ability to interact with the wood surface and has the potential to be used as a protection for wood in sensitive environments.
木材的涂层有时必须为木质元素提供美观和基本的保护，并防止微生物的发展和传播。为此，目前已经提供了几种含有不同纳米粒子的聚合物。本研究提出了一种新型的聚（偏二氟乙烯-共-六氟丙烯）（PVDF-HFP）/聚乙烯吡咯烷酮（PVP）聚合物复合材料，其中含有 MoO 纳米线，能够在木材上形成涂层薄膜。所开发的涂层的薄膜表现出弹性行为，这取决于涂层薄膜的厚度[测试的湿膜厚度（90、180 和 360 μm）]。该涂层表现出与普通山毛榉（Fagus sylvatica L.）木材表面良好相互作用的能力，表现在润湿方面（接触角为 15.6°），在表面上快速溢出，涂层在木材结构中的良好渗透以及形成厚度可达 40 μm 的薄膜，具有优异的剥离附着力（6 MPa）。用含有 C 和 MoO 的二甲酰胺溶剂对木材进行蚀刻，是导致涂覆 C 和 MoO 的木材表面粗糙度增加的原因。此外，由于存在 C 和 MoO，涂覆木材的疏水性显著提高，与未涂覆木材上最初测量的 46°相比，水的接触角提高到 123°。用紫外线照射木材表面，导致未涂覆和涂覆木材的表面颜色发生明显变化。用 C 和 MoO 涂覆的木材具有良好的耐水、耐酒精和干热（3 到 4 级）的性能。抗菌测试表明，涂层中 MoO 的存在对涂覆木材抵抗蓝变真菌和霉菌生长的能力起着重要作用。所开发的 PVDF-HFP/PVP/MoO 涂层具有与木材表面良好的相互作用能力，有潜力在敏感环境中用作木材的保护材料。
