Chemical characterization of wood treated with a formulation based on propolis, caffeine and organosilanes

Abstract

The aim of the study was to present chemical characteristics of a potential wood protection system composed of three chemical components. The paper presents preliminary results of chemical and biological analysis of wood treated with a mixture of 30% ethanol extract of propolis, caffeine and organosilanes: methyltrimetoxysilane (MTMOS) and octyltriethoxysilane (OTEOS). The sapwood of Scots pine (Pinus sylvestris L.) was impregnated with the above mentioned solution by vacuum method. The samples of wood treated with preservative were subjected to accelerated aging procedure according to EN 84 and subsequently to mycological tests according to the modified EN 113. Structural analysis of the treated wood was performed using infrared spectroscopy FTIR. The concentration of silicon in wood samples was determined by atomic absorption spectrometry AAS. The percentage content of nitrogen in wood samples was determined by elementary analysis EA. Slight differences in nitrogen and silicon content recorded in wood samples following impregnation and leaching confirm the permanent character of bonding between the propolis-silane-caffeine preparation and wood. The stable character of Si-C and Si-O bonds was shown in IR spectra and discussed in detail in this paper.

The Possibility of Propolis Extract Application in Wood Protection

“…The weight loss of the wood treated with chitosan oligomers and propolis after 30 days of exposure to T. versicolor was 32.8% compared to 42.3% of the weight loss of the untreated wood [33]. The pine wood impregnated with the preparation consisting of propolis extract, caffeine and organosilanes (methyltrimethoxysilane and octyltrimethoxysilane) was five times more resistant against the activity of C. puteana than the unprotected samples [34]. The earlier work of authors indicated that pine wood treated with the extract of Polish propolis with silicon compounds was more durable against C. puteana than untreated wood [36,39].…”

“…The changes in the FTIR spectrum of the wood following the action of brown-rot fungi, including C. puteana, which selectively decay carbohydrates and limit lignin degradation, have been described in the literature [34,[42][43][44][45][46][47]. The most important changes in the spectrum of wood exposure to C. puteana were observed in the fingerprint region, between 1800 and 600 cm −1 and were characterized on the basis of the literature data [13,33,[42][43][44][45][46][47].…”

“…Propolis was also used as a constituent of the preparation containing chitosan, propolis extract and silver nanoparticles in preventing the decay of wood caused by T. versicolor [32,33]. The preparation based on propolis extract, caffeine and organosilanes was tested in protection of wood against brown-rot fungus C. puteana [34]. In addition, according to the literature data, wood treated with the propolis extract with silicon compounds showed an increased resistance against C. puteana and improved hydrophobic properties [35,36].…”

Natural Compounds for Wood Protection against Fungi—A Review

“…However promising in wood protection against fungi, caffeine turned out to be easily leachable from wood, which is its main disadvantage precluding it from application for wood used outdoors [ 116 ]. Therefore, several attempts have been made to stabilise caffeine inside the wood structure using organosilicon compounds [ 117 ] or a mixture of silanes and propolis [ 118 ].…”

Development of composition formulations, based on natural bischofite, to protect wood from fire

“…There is a need to develop and implement measures to prevent and eliminate the consequences of bio-damage to various building materials and structures. Specifically, the mineral bischofite allows for an effective environmental safety of materials and operation of building facilities [8,9]. Bischofite (MgCl 2 • 6H 2 O) is the most soluble natural salt, extracted to the surface by underground dissolution with fresh water; in terms of the total activity of natural radionuclides, it refers to a first class and can be used without restrictions.…”