Jeżo Aleksandra, Poohphajai Faksawat, Herrera Diaz Rene, Kowaluk Grzegorz
Institute of Wood Sciences and Furniture, Warsaw University of Life Sciences-SGGW, Nowoursynowska St. 159, 02-776 Warsaw, Poland.
InnoRenew CoE, Livade 6a, 6310 Izola, Slovenia.
Materials (Basel). 2024 Aug 5;17(15):3868. doi: 10.3390/ma17153868.
Finishing coatings in the wood-based composites industry not only influence the final appearance of the product but also serve to protect against fungi and molds and reduce the release of harmful substances, particularly formaldehyde and volatile organic compounds (VOCs). Carbon-rich materials, such as those derived from birch bark extraction, specifically suberin acids, can fulfill this role. Previous research has demonstrated that adding suberin acid residues (SAR) at 20% and 50% by weight significantly enhances the gas barrier properties of surface-finishing materials based on poly(lactide) (PLA) and polycaprolactone (PCL), particularly in terms of total VOC (TVOC) and formaldehyde emissions. This study aims to explore whether these properties can be further improved through the incorporation of nano-zinc oxide (nano-ZnO). Previous research has shown that these nanoparticles possess strong resistance to biological factors and can positively affect the characteristics of nanofilms applied as surface protection. The study employed PLA and PCL finishing layers blended with SAR powder at 10% / and included 2% and 4% nano-zinc oxide nanoparticles. The resulting blends were milled to create a powder, which was subsequently pressed into 1 mm-thick films. These films were then applied to raw particleboard surfaces. TVOC and formaldehyde emission tests were conducted. Additionally, the fungal resistance of the coated surfaces was assessed. The results showed that PLA/SAR and PCL/SAR composites with the addition of nano-zinc oxide nanoparticles exhibited significantly improved barrier properties, offering a promising avenue for developing biodegradable, formaldehyde-free coatings with enhanced features in the furniture industry. Furthermore, by utilizing SAR as a post-extraction residue, this project aligns perfectly with the concept of upcycling.
木质复合材料行业中的面漆不仅会影响产品的最终外观，还能起到防止真菌和霉菌滋生的作用，并减少有害物质的释放，尤其是甲醛和挥发性有机化合物（VOC）。富含碳的材料，如从桦树皮提取物中获得的材料，特别是软木脂酸，能够发挥这一作用。先前的研究表明，按重量计添加20%和50%的软木脂酸残基（SAR）可显著提高基于聚乳酸（PLA）和聚己内酯（PCL）的表面处理材料的气体阻隔性能，特别是在总VOC（TVOC）和甲醛排放方面。本研究旨在探索通过掺入纳米氧化锌（nano-ZnO）是否可以进一步改善这些性能。先前的研究表明，这些纳米颗粒对生物因素具有很强的抵抗力，并且可以对用作表面保护的纳米薄膜的特性产生积极影响。该研究采用了与10%的SAR粉末混合的PLA和PCL涂饰层，并加入了2%和4%的纳米氧化锌纳米颗粒。将得到的混合物研磨成粉末，随后压制成1毫米厚的薄膜。然后将这些薄膜应用于原始刨花板表面。进行了TVOC和甲醛排放测试。此外，还评估了涂层表面的抗真菌性能。结果表明，添加纳米氧化锌纳米颗粒的PLA/SAR和PCL/SAR复合材料表现出显著改善的阻隔性能，为在家具行业开发具有增强特性的可生物降解、无甲醛涂层提供了一条有前景的途径。此外，通过将SAR用作提取后的残留物，该项目与升级再利用的概念完美契合。
