Fire Resistance Of Wood Research Articles

Eco-Friendly Polymer Nanocomposite Coatings for Next-Generation Fire Retardants for Building Materials.

The increasing global commitment to carbon neutrality has propelled a heightened focus on sustainable construction materials, with wood emerging as pivotal due to its environmental benefits. This review explores the development and application of eco-friendly polymer nanocomposite coatings to enhance wood's fire resistance, addressing a critical limitation in its widespread adoption. These nanocomposites demonstrate improved thermal stability and char formation properties by integrating nanoparticles, such as nano-clays, graphene oxide, and metal oxides, into biopolymer matrices. This significantly mitigates the flammability of wood substrates, creating a robust barrier against heat and oxygen. The review provides a comprehensive examination of these advanced coatings' synthesis, characterization, and performance. By emphasizing recent innovations and outlining future research directions, this review underscores the potential of eco-friendly polymer nanocomposite coatings as next-generation fire retardants. This advancement supports the expanded utilization of wood in sustainable construction practices and aligns with global initiatives toward achieving carbon neutrality.

한옥의 내화 및 방충 성능 개선에 관한 연구

This paper is a study on the fire resistance of wood and securing the performance of insects, which are still emerging as problems in order to convert the various advantages and excellence of hanok into modern architectural methods. To verify the research results, the test was conducted by applying it to the building materials of hanok, and the results of the research were summarized as follows.
 First, wood with fire resistance regulations is relatively safe from fire. Wood has a very low heat transfer rate and a relatively low ignition temperature on the surface is a relatively safe material compared to other materials because when a fire breaks out, the carbonized part of the surface additionally blocks heat transfer and prevents the inside from being carbonized.
 Second, in the case of hanok, the standard of the member that can be used as a fireproof material is 460mm×600mm long in the case of beams, 360mm in diameter, 3,600mm high in the case of cylinders, and 300mm×300mm high in each column.
 Third, in order to prevent insects such as termites, insect repellent paint is directly applied to wood, a building material, to show the performance of the room. In comparison to existing termite damage prevention methods such as fumigation, soil treatment, and termite colony removal systems, insect repellent paints show excellent performance in difficulty, cost, use of eco-friendly products, and room effects.

Progressive Methods in Studying the Charred Layer Parameters Change in Relation to Wood Moisture Content.

The aim was to investigate the relationship of charred layer parameters (also wood fire resistance) and moisture content of European larch (Larix decidua L.) wood. For this purpose, finite element model (FEM) was developed. To develop FEM, ANSYS software and transient thermal analysis were applied. To validate developed FEM, the medium-scale fire tests were provided in the laboratory chamber. In the fire tests the beams made of larch wood have undergone the thermal loading with radiant panel. The FEM validation results showed very strong correspondence of numerical and experimental results, when achieving the overall accuracy of 93.4%. Validated FEM was further used to determine the relationship between the larch beams moisture content and formation of charred layer, i.e., its parameters. The results from the simulation pointed out the fact, the wetter the wood, the higher its fire resistance. This is very important information for studying the formation of a charred layer and a layer of degraded wood. After increasing the moisture content from 10% to 30%, the area of the charred layer decreased by approximately 20%. The area of degraded wood decreased by almost 30%, so it can be stated that the area of the charred layer of wood and degraded wood decreases exponentially with increasing wood moisture content.

Ecological structure: production of organic impregnation material from mussel shell and combustion

In the research, sea mussel shell (Chamelea gallina) powders were impregnated on the samples of Eastern spruce (Picea orientalis (L.) Link.) and Anatolian chestnut (Castanea sativa Mill.) by dipping method at different concentrations (1%, 5%, 10%, 15%). To investigate the level of use in the wood industry and especially its effects against fire; adhesion, thermogravimetric analysis (TGA), limiting oxygen index (LOI) test measurements were carried out. According to the TGA results, while the residue quantity in the spruce wood sample was the highest at 5%, the residue amount in the chestnut wood sample was the highest at 15%. With increasing amounts of mussel shell powder, the limiting oxygen index values in both wood species samples increased. As a result, it was discovered that impregnating wood samples with mussel shell powder improved the wood's fire resistance.

Перспективна технологія промислового виробництва водню

Search for new highly efficient agents for wood fire retardant treatment in the construction has been conducted more and more intensively. But fire retardant treatment nowadays should not only ensure specified fire resistance of wood but preserve its performance as well as ensure its environmental safety and durability. Therefore a significant problem of ensuring vital activities and safe functioning of building facilities lies in the development of intumescent coatings for building structures taking into consideration economical, processing and environmental aspects; these coatings shall be used not only on a par with existing similar ones but be highly efficient in special spheres of construction which makes it possible to prevent occurrence of man-caused accidents. The paper shows results of the studies purposed at raising efficiency of the facilities protection by conversion of the cellulose containing materials used at them to the group of hardly combustible materials; it was revealed that application of appropriate composition converted the wood into hardly combustible material that did not spread flame across its surface and had moderate smoke production ability. Taking into account these fire hazard indices the wood having been subjected to fire retardant treatment as construction material could be allowed for application for the internal lining of rooms including those at the escape routes. Hydrogen energy also meets global trends in autonomous and local energy consumption. The concept of "home power plant" appears in European energy programs. Such mini-power plants with a capacity of not more than 5 kW are environmentally friendly because they allow you to produce as much electricity as the consumer needs, and consume it without the losses inevitable in large energy with its thousands of kilometers of power lines. It is likely that hydrogen energy closes the topical issues: how to make all possible energy sources more interconnected, how to minimize their overall impact on the environment. Because this energy source is more universal, more flexible to use and more environmentally friendly.

Відповідність вогнезахисних целюлозовмісних матеріалів екологічній безпеці

Search for new highly efficient agents for wood fire retardant treatment in the construction has been conducted more and more intensively. But fire retardant treatment nowadays should not only ensure specified fire resistance of wood but preserve its performance as well as ensure its environmental safety and durability. Therefore a significant problem of ensuring vital activities and safe functioning of building facilities lies in the development of intumescent coatings for building structures taking into consideration economical, processing and environmental aspects; these coatings shall be used not only on a par with existing similar ones but be highly efficient in special spheres of construction which makes it possible to prevent occurrence of man-caused accidents. The paper shows results of the studies purposed at raising efficiency of the facilities protection by conversion of the cellulose containing materials used at them to the group of hardly combustible materials; it was revealed that application of appropriate composition converted the wood into hardly combustible material that did not spread flame across its surface and had moderate smoke production ability. Taking into account these fire hazard indices the wood having been subjected to fire retardant treatment as construction material could be allowed for application for the internal lining of rooms including those at the escape routes.

INVESTIGATION OF THE FIRE-RETARDANT EFFECTIVENESS OF PHOSPHORUS-CONTAINING IMPREGNATING COMPOUNDS FOR WOOD

The paper presents the results of comparative studies of the flame-retardant effectiveness of impregnating compounds based on a phosphor-containing oligomer and dimethylphosphite. It is shown that phosphorus-containing impregnating compounds increase the resistance to thermal-oxidative degradation, as well as the fire resistance of wood.

Study on Temperature-Dependent Properties and Fire Resistance of Metakaolin-Based Geopolymer Foams.

This paper presents temperature-dependent properties and fire resistance of geopolymer foams made of ground basalt fibers, aluminum foaming agents, and potassium-activated metakaolin-based geopolymers. Temperature-dependent properties of basalt-reinforced geopolymer foams (BGFs) were investigated by a series of measurements, including apparent density, water absorption, mass loss, drying shrinkage, compressive and flexural strengths, XRD, and SEM. Results showed that the apparent density and drying shrinkage of the BGFs increase with increasing the treated temperature from 400 to 1200 °C. Below 600 °C the mass loss is enhanced while the water absorption is reduced and they both vary slightly between 600 and 1000 °C. Above 1000 °C the mass loss is decreased rapidly, whereas the water absorption is increased. The compressive and flexural strengths of the BGFs with high fiber content are improved significantly at temperatures over 600 °C and achieved the maximum at 1200 °C. The BGF with high fiber loading at 1200 °C exhibited a substantial increase in compressive strength by 108% and flexural strength by 116% compared to that at room temperature. The enhancement in the BGF strengths at high temperatures is attributed to the development of crystalline phases and structural densification. Therefore, the BGFs with high fiber loading have extraordinary mechanical stability at high temperatures. The fire resistance of wood and steel plates has been considerably improved after coating a BGF layer on their surface. The coated BGF remained its structural integrity without any considerable macroscopic damage after fire resistance test. The longest fire-resistant times for the wood and steel plates were 99 and 134 min, respectively. In general, the BGFs with excellent fire resistance have great potential for fire protection applications.

Изучение кинетики термической и термоокислительной деструкции обработанной антипиренами и необработанной древесины

Разработана экспериментальная методика определения механизма огнезащитного действия антипиренов на основе изучения кинетики термической и термоокислительной деструкции древесины. Отработка методики проведена на антипирене MgCl (бишофит). Методика основывается на количественной оценке при термическом разложении древесины выхода продуктов деструкции: CO, CO, дымового аэрозоля. В качестве приборной базы используются хроматографы, фотометр фотоэлектрический для аэрозолей, спектрофотометр. Water with various additives is used during extinguishing forest fires. Fire-retardants are used as additives in most cases. The selection of fire-retardants depends on the level of increase in extinguishing effectiveness at their addition to water. The purpose of this work is to develop an experimental method for evaluating the fireproof effect of flame retardants solutions. This method is based on the investigation of the kinetics of thermal and thermo-oxidative degradation of treated wood with flame retardants and untreated wood. In practice, bischofite and diammonium phosphate are often used as additives. Investigations were conducted using MgCl (bischofite). The explanation of the fireproof effect of the bischofite solution is based on the study of the yield of decomposition products (CO, CO, smoke aerosol) of wood treated with fire-retardant and untreated wood. The instrument base includes chromatographs «Gasochrom 3101», «Tsvet 152», photoelectric photometer for aerosols, spectrophotometer IKS-29. Wood samples were subjected to thermal and thermo-oxidative degradation in nitrogen flow or air flow with a volume velocity of 60 ml · min. Pulse heating in the pyrolysis furnace was carried out in the temperature range from 350 to 550 °C. The significant increase in fire resistance of wood treated with fire-retardant was found as a result of researches using the proposed method. It was shown that the theory of the coating layer, thermal and gas theory of catalytic dehydration are not suitable for explaining the mechanism of fireproof action of an aqueous solution of magnesium halides. Although it is not excluded the inhibition of gas-phase oxidation of cellulose degradation products by hydrogen halides released when heating aqueous solutions of magnesium halides.

Functionalized Surface Layer on Poplar Wood Fabricated by Fire Retardant and Thermal Densification. Part 1: Compression Recovery and Flammability

To enhance compression stability and fire retardancy of densified wood, a new modification method i.e., combined nitrogen–phosphorus (NP) fire retardant pre-impregnation with surface thermo-mechanical densification is used to fabricate a certain thickness of functionalized surface layer on poplar. This combined treated wood is investigated via vertical density profile (VDP), and the compression stability is revealed by both soaking test and cone analysis. Results demonstrate that the combined treatment hardened the surface of wood and reformed the interface combination of the NP with the wood cell wall, thus making the surface tissue more close-grained. Fire retardancy was also enhanced; the total heat release and CO generation values decreased by 21.9% and 68.4%, respectively, when compared with that of solely NP-treated wood. Moreover, surface hardness increased by 15.8%, and the recovery of surface hardness and thickness were 56.8% and 77.2% lower than that of simply densified wood. It appears that this NP-involved thermal densification could be considered as an alternative approach to enhance both the compression stability and fire resistance of wood.

ДО ПИТАННЯ ДОСЛІДЖЕННЯ ЗМІНИ ТЕМПЕРАТУР В РЕАКЦІЙНІЙ КАМЕРІ ПРИ ВИПРОБУВАННЯХ ЗРАЗКІВ З ДЕРЕВИНИ

Purpose. Investigation of temperature changes in the reaction chamber when testing samples from wood. Methodology. Theoretical and practical studies of fire resistance, increase of fire resistance and processes of heat and mass transfer during combustion of wooden constructions, simulation of combustion processes in conditions of developed fire. Findings. Studies have shown that a significant amount of heat is introduced into the reaction chamber when combusted, as evidenced by a significant increase in temperature throughout the chamber. In samples treated with liquid glass, the process of raising the temperature is slower than in the raw samples, Their temperature exceeds the temperature calculated according to the standard temperature curve of the fire. This indicates that under the flame retardant coating of liquid glass with a thickness of up to 1 mm, the process of decomposition and burning of wood is active. In this, a significant part of heat is allocated, which is indicated by an increase in temperature compared with the temperature in the chamber without specimens. It was established that the process of combustion of samples processed in warehouses 1, 2, 3 proceeds identically in accordance with the general laws. At the initial stage there is a sharp increase in temperature, and then the process of combustion becomes more smooth. This is due to the fact that in the initial period of time (1-2 min) due to inertia, the coating does not expose instantly, but with some delay, because for this it needs a significant warming up to a temperature of 3000C and above. And during this time, simultaneously with the heating of the fire protection coating is an intensive process of heating the upper layers of wood and its active decomposition which is reflected in the increase in temperature on the surface of the samples. Then there is a swelling of the coating. The expanded coating reduces the heat transfer to the wood, which also affects the reduction of the burning rate under the coating (the temperature on the surface of the coating rises, but the increase is more smoothly than at the beginning of the test). Originality. Based on the conducted analytical studies and modeling of the heat-mass transfer process, the effect of combustion on the change of the parameters of combustibility and fire resistance of wood is revealed. Practical value. It is to increase the safety of the operation of construction objects, the safety of evacuation of people and safety of emergency rescue works due to the application of developed effective compositions that reduce the combustibility of materials and increase the time for safe operation of structures in extreme conditions.

Thermal oxidative degradation of wood modified with aminophenylborates

Comparative thermal analysis in the presence of oxygen was carried out for samples of native pine wood and wood samples modified with aminophenylborates. Significant decrease in the amount of heat released during thermal decomposition of the modified samples was established, which is due to the increase of carbonaceous residues on the surface. Reduction of heat release during decomposition of the modified samples may be explained by the lower yield of combustible volatile products as well as by thin film of boron oxide, formed on the surface of the modified wood, that partially reflects heat flow. Produced upon the modifier decomposition water vapor and inert nitrogen oxides dilute gaseous mixture near the wood surface and isolate it from oxygen. This enhances fire-resistance of wood modified with mono- and diethanolamine(N→B)phenylborates. Hydroxyl group at the sixth carbon atom of the glucopyranose ring of cellulose participates in reactions of cellulose modification, which prevents formation of flammable levoglucosan and, consequently, improves the fire-resistance of the modified wood.

Dimensional Stability, Mechanical Properties and Fire Resistance of MUF-Boron Treated Wood

In order to improve the dimensional stability, mechanical properties and fire resistance of the wood from Cryptomeria fortunei, the melamine-urea-formaldehyde (MUF) resin and the mixture of MUF/boric acid/borax (MBB) were prepared and used as the wood modification solution. Results show that both the MUF resin and the MBB solutions exhibit good permeability to wood. Under the same treatment conditions, the weight percent gains (WPG) of treated wood increases with the increasing concentration of modification solutions. MUF and MBB modification solutions can effectively enhance the dimensional stability, MOR, MOE and fire resistance of wood. Compared with MBB treated wood, MUF treated wood exhibits higher MOR and dimensional stability. The MBB treated wood has higher MOE and fire resistance than MUF treated wood.

Enhancement of Biological and Physical Properties of Wood by Boric Acid-Vinyl Monomer Combination Treatment

Boron treatment was combined with vinyl polymerization to improve leaching resistance of boron from wood, as well as dimensional stability, biological and fire resistance of wood. Boric acid (BA) was impregnated into wood specimens [sapwood of Cryptomeria japonica D. Don. 20 (T) x 20 (R) x 10 (L)mm] as 1% aqueous solution prior to vinyl monomer treatment. Styrene (ST), methylmetacrylate (MMA) and their mixtures (50:50, v/v) were impregnated in the presence of catalyzer and a crosslinker. Polymerization was conducted by heat radiation method at 90°C for 4h. Treated specimens were then subjected to decay and termite tests, as well as oxygen index (O.I) determination. Anti-swelling efficiency (ASE) and water absorption levels (WA) were also measured by standardized methods. Vinyl monomers succeeded in reducing WA of wood to a minimum level and delay boron leaching considerably. The treated wood proved to be resistant against two decay fungi, Tyromyces palustris and Coriolus versicolor and very destructive termite Coptotermes formosanus even after ten severe weathering cycles. BA increased the O.I. levels of monomer-treated wood, which resulted in a lower flame spread index. Moreover, BA suppressed the smoke generation due to monomer cooperation in wood.