Novel David, Ghio Simone, Gaiardo Andrea, Picciotto Antonino, Guidi Vincenzo, Speranza Giorgio, Boscardin Maurizio, Bellutti Pierluigi, Pugno Nicola M
Laboratory of Bio-Inspired, Bionic, Nano, Meta Materials & Mechanics, Department of Civil, Environmental and Mechanical Engineering, University of Trento, via Mesiano 77, I-38123 Trento, Italy.
Centre for Materials and Microsystems, Fondazione Bruno Kessler, via Sommarive 18, I-38123 Trento, Italy.
Nanomaterials (Basel). 2020 Mar 6;10(3):478. doi: 10.3390/nano10030478.
Recently, several chemical and physical treatments were developed to improve different properties of wood. Such treatments are applicable to many types of cellulose-based materials. Densification leads the group in terms of mechanical results and comprises a chemical treatment followed by a thermo-compression stage. First, chemicals selectively etch the matrix of lignin and hemicellulose. Then, thermo-compression increases the packing density of cellulose microfibrils boosting mechanical performance. In this paper, in comparison with the state-of-the-art for wood treatments we introduce an additional nano-reinforcemeent on densified giant reed to further improve the mechanical performance. The modified nanocomposite materials are stiffer, stronger, tougher and show higher fire resistance. After the addition of nanoparticles, no relevant structural modification is induced as they are located in the gaps between cellulose microfibrils. Their peculiar positioning could increase the interfacial adhesion energy and improve the stress transfer between cellulose microfibrils. The presented process stands as a viable solution to introduce nanoparticles as new functionalities into cellulose-based natural materials.
最近，人们开发了几种化学和物理处理方法来改善木材的不同性能。此类处理方法适用于多种纤维素基材料。在机械性能方面，致密化处理效果最佳，它包括一个化学处理阶段，随后是热压缩阶段。首先，化学物质选择性地蚀刻木质素和半纤维素的基质。然后，热压缩提高了纤维素微纤丝的堆积密度，从而提升了机械性能。在本文中，与木材处理的现有技术相比，我们在致密化的巨型芦苇中引入了额外的纳米增强材料，以进一步提高机械性能。改性后的纳米复合材料更硬、更强、更坚韧，并且具有更高的耐火性。添加纳米颗粒后，由于它们位于纤维素微纤丝之间的间隙中，因此不会引起相关的结构改性。它们独特的定位可以增加界面粘附能，并改善纤维素微纤丝之间的应力传递。所提出的工艺是一种可行的解决方案，可将纳米颗粒作为新功能引入纤维素基天然材料中。
