Wood Surface Modification with Hybrid Materials Based on Multi-Walled Carbon Nanotubes

Abstract

In this work, new treatments based on multi-walled carbon nanotubes (MWCNTs), MWCNTs decorated with zinc oxide (ZnO), MWCNTs decorated with hydroxyapatite (HAp) and MWCNTs decorated with silver (Ag) nanoparticles dispersed in PHBHV solution are proposed for improving sound oak wood properties. We hypothesize that the solutions containing decorated MWCNTs will be more efficient as wood consolidants, not only because of the improved mechanical properties of the treated wood but also because of the hydrophobic layer created on the wood surface. In order to test these hypotheses, the treatments’ potential was investigated by a number of complex methods, such as colorimetric parameter measurements, water absorption tests, mechanical tests, artificial aging and antifungal tests. The data confirm that the treated wood materials have moderate stability, and the color differences are not perceived with the naked eye. A significant improvement of the treated samples was observed by water absorption, humidity and mechanical tests compared to untreated wood. The best results were obtained for samples treated by brushing with solutions based on decorated CNTs, which confirms that a uniform and thicker layer is needed on the surface to ensure better protection. The wood behavior with accelerated aging revealed that the control sample degraded faster compared to the other treated samples. Antifungal tests showed that higher growth inhibition was obtained for samples treated with 0.2% MWCNTs_ZnO + PHBHV. Considering all of the obtained results, it can be concluded that the most effective treatment was MWCNTs_ZnO + PHBHV at a nanocomposite concentration of 0.2%, applied by brushing. Thus, wood protection against mold and fungi will be achieved, simultaneously ensuring improved mechanical strength and water barrier properties and therefore maintaining the structural integrity of sound oak wood over time.

Antifungal Agents in Wood Protection—A Review

“…This section discusses the results of studies on the antifungal activity of synthetic compounds for wood protection presented in the literature. The section focuses on three main groups of synthetic agents: silicon compounds, ionic liquids, nanoparticles and nano-compounds, which have been tested in wood protection [ 7 , 159 , 160 , 161 ].…”

The Effect of UV Irradiation on the Stability of Coated Fir Wood Samples

“…The acceleratedaging procedure was developed to assess the durability potential of wood specimens, by testing the weathering resistance by simulating the sunlight irradiance using a mercury lamp. A time interval of 400-2000 hours of irradiation is considered as about 2 years of weathering [14,15]. The consolidating effect of acrylic protection coatings was investigated by: colorimetric analysis, mechanical strength testing, and water absorption test, determinations which were performed before and after irradiation for highlighting the changes during irradiation.…”

Effects of Different End Functional Groups Hyperbranched Polymers-Modified Carbon Nanotubes on the Crystallization and Mechanical Properties of Poly(l-lactic acid) (PLLA)

“… 15 On the basis of the above issues, the current researchers propose that the surface modification of CNTs could solve this problem. 16 …”

“…15 basis of the above issues, the current researchers propose that the surface modification of CNTs could solve this problem. 16 At present, the modification of CNTs is mainly focused on a small molecule compound and long chain polymer. A small molecule compound usually has few functional groups and limited bonding ability with a polymer matrix.…”

“…However, in the actual application process, because of the high surface energy of CNTs, agglomeration occurs in the mixing process, which ultimately plays a limited strengthening role or reduces the original properties of the material . On the basis of the above issues, the current researchers propose that the surface modification of CNTs could solve this problem …”