Improvement of dimensional stability of wood by silica nanoparticles

What is it about?

In this study, silica nanoparticles were prepared by hydrolysis and condensation of TEOS at high pH. This step of preparing hydrophilic spherical nanoparticles was followed by a modification step with hexadecyltrimethoxysilane (HDTMS), resulting in the grafting of long-chain alkyl groups onto the surface of the nanoparticles to make them hydrophobic. To get better bonding to the wood surface, PDMS was used as bonding agent between the HDTMS-coated silica nanoparticles and wood. The novelty of this research is the application of such nanoparticles not only as surface coating, but a full cross section impregnation, which utilization form in case of wood material was not investigated yet. The planned treatment will likely elongate the lifetime of the wood-based products, because the wood-water relations are essential at all utilization fields. The expected positive effect of the investigated treatments is the improvement of the dimensional stability of wood as a result of impregnation with hydrophobic silica nanoparticles. The aim of this work was to improve the dimensional stability of wood material by the use of hydrophobized spherical silica-nanoparticles. Another goal was to improve the effect of the treatment by the use of polydimethylsiloxane (PDMS) as bonding agent between the nanoparticles and the wood surface.

Featured Image

Why is it important?

The improving effect of nanoparticles on wood dimensional stability is barely known nowadays. Contrarily, nanoparticles are commonly used in other industries because of their favourable properties. A lot of promising results were achieved with the use of silica nanoparticles in relation to the mechanical, combustion, hydrophobic and some other properties of different polymers, papers or textiles. However, regarding the utilization of nanoparticles to improve the wood properties, some positive results are available as well. With the use of different nanoparticles the moisture uptake is reducible, UV-protection, mechanical properties and durability is improvable. In some cases fire resistance could be improved as well.