Fire resistance of wood treated with a cationic silica sol

Abstract

Wood was treated with the cationic silica sol (CSS) Levasil 200S and dried at various temperatures (room temperature, 40, 60, 80 and 103°C). A water leaching test revealed fixation of the silica in wood even after drying at room temperature. Maximum cross sectional swelling of the specimens decreased from 15.6 % (untreated control) to 13.0 %, when treated wood was dried at 103°C; cell wall bulking values were also negative (-2.3 %), indicating a thermal degradation of the cell wall polymers catalyzed by the CSS. Penetration of the CSS into the cell wall did not occur. A simple flammability test revealed increased fire resistance of the treated wood. Mass loss and velocity of mass loss as well as burning time were reduced; glowing of the formed charcoal was completely prevented. The effectiveness increased with increasing weight percent gain of the CSS in the wood. Thermo gravimetric analysis under nitrogen atmosphere displayed only minor reduction in the initial temperature of thermal decomposition for wood treated with CSS as compared to the control. In the presence of oxygen the resulting charcoal showed comparable thermal behaviour to the control. The yield of charcoal after pyrolysis was increased to a minor extent (from 19.9 to 23.0 %), indicating that the release of combustible gases was hardly reduced. The mode of action of enhanced fire resistance due to CSStreatment is discussed.

Surface free energy and dynamic wettability of wood simultaneously treated with acidic dye and flame retardant

“…Wood dyeing eliminates color differences and improves the visual characteristics of wood products; more importantly, dyeing wood like fast-growing poplar wood can make them appear similar to higher valued wood species. Another disadvantageous property of wood (especially the fast-growing woods) is its flammability which restricts its application in furniture, decoration, and construction industries [5][6][7][8]. Flame-retardancy treatment is a crucial precautionary measure for wood materials [9].…”

Improvement of Mechanical, Hydrophobicity and Thermal Properties of Chinese Fir Wood by Impregnation of Nano Silica Sol

“…In order to improve the bleed resistance of inorganic salts, some scholars have begun to use the sol-gel method to prepare inorganic wood composite [ 6 , 7 ]. The main raw materials used in the sol-gel process are metal alkoxides, which are used as precursors, such as tetraethoxysilane (TEOS), 2-heptadecafluorooctylethyltrimet-hoxysilane (HFOETMOS), methyltrimethoxysilane (MTMOS), and polydimethylsiloxane (PDMS) [ 13 , 14 , 15 , 16 , 17 , 18 , 19 ]. Other reagents have also been investigated as precursors, including silicon alkoxides, silicon alkoxides derivatives, titanium alkoxides, and titanium alkoxides derivatives [ 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 ].…”

Preparation of small particle diameter thermally expandable microspheres under atmospheric pressure for potential utilization in wood

“…Among which the dimensional instability caused by water in wood gains extensive attention. 7 In addition, the resistance of decay and fire, 8,9 and the antiweathering properties 10 need to be improved urgently for outdoor service. Especially, numerous fast-growing trees are planted to alleviate the shortage of wood, including poplar, eucalyptus, and fir, bringing about a contradiction between the promotions of their utilization as solid wood and poor qualities.…”