INVESTIGATION OF FIRE-RESISTANT PROPERTIES OF WOOD MATERIALS MODIFIED WITH BORON AND ZINC CONTAINING FLAME RETARDANTS-ANTISEPTICS

ABSTRACT

In this research work, on the basis of existing regulatory requirements, the features of fire resistance of products obtained on the basis of modification of wood materials with oligomer flame retardants-antiseptics were studied. In the course of practical experiments, it was found that the weight loss after modification of the wood material by boron and zinc-containing oligomer flame-retardants is 6.5%. Also, the indicators of effectiveness in increasing the fire-resistant nature of the wood materials of the antipyrine obtained in the test-experiments studied.

АННОТАЦИЯ

В данной исследовательской работе на основе существующих нормативных требований были изучены особенности огнестойкости изделий, полученных на основе модификации древесных материалов олигомерными антипиренами-антисептиками. В ходе практических экспериментов было установлено, что потеря веса после модификации древесного материала олигомерными антипиренами, содержащими бор и цинк, составляет 6,5%. Также изучались показатели эффективности в повышении огнестойкости древесных материалов антипирина, полученные в тест-экспериментах.

Ключевые слова: деревянные строительные материалы, олигомерный антипирин, огнестойкие.

Keywords: wooden building materials, oligomeric antipyrenes, fireproof.

Introduction. Various oligomer flame-retardants for fire protection of wooden building materials produced all over the world. When the composition of these oligomer flame-retardants studied, it was found that these are mainly organic compounds and substances containing ammonium phosphate, ammonium sulfate, sodium fluoride, boric acid, silicic acid salts, carbamate, ammonium and phosphorus carbonates. In recent times, research has been underway to obtain antipyrenes for wood materials in an economically efficient way from these compositions [1-2].

Oligomer flame-retardants of BS-1, BS-2 and BS-3 brands containing boron and zinc for fire protection of wood materials were obtain in laboratory experiments of this study [3]. The effectiveness of fire protection of wood materials with these flame-retardants was studied based on GOST 16363-98 [5] and the biological stability of GOST 9.048-89 [6].

Methods and materials. A 20% solution of oligomer flame retardant antiseptic of BS-1, BS-2 and BS-3 brands was prepared in water and samples of wood (pine) kept for hour in a special bath at a temperature of 40-50°C. During the experiment, samples of antipyrene suspended wood were place vertically in a black steel pipe with a length of 166 mm and a diameter of 50 mm. At a distance of 5 mm from the pipe obtained for the experiment, an alcohol-burning flame was provide from the bottom of the samples [2]. The distance from the upper edge of the burn to the sample is 10 mm the holding time of the sample in the flame is 2 min. After the sample was extract from the flame, the independent flame of the sample and the duration of the flame studied and recorded.

The essence of this research method is to determine the mass loss of wood treated with coatings tested in favorable conditions for heat accumulation and during fire tests.

In practical experiments, the air temperature was 22°C, the atmospheric pressure was 720-725 mm Hg, the relative humidity was set at 55-57%. The results of experimental testing of non-treated wood materials with oligomer antipyrene-antiseptic of the brands BS-1, BS-2 and BS-3 presented in the tables below.

Table 1

Indicators of wood materials that aren’t treated with antipyrenes

In this table 1, the fire resistance of non-treated samples of wooden materials with antipyrenes is studied. The resulting sample mass loss was 66,5%. This specimen has been found to belong to a flammable group.

The results of the study of fire resistance of wood materials treated with a BS-1 brand oligomer antipyrene-antiseptic in accordance with the requirements of the standard were found that the mass loss of the average sample was 6,5%. This indicates that fireproof materials belong to group 1 (table 2).

Table 2

Indicators of wood materials treated with BS-1 brand oligomer antipyrene-antiseptic

The study found that the mass loss of the average sample was 7.8% according to the results of research of fireproof properties of wood materials treated with BS-2 brand oligomer antipyrene-antiseptic in accordance with the tests. This result characterizes the group 1 flamethrower feature (table 3).

Table 3

Indicators of wood materials treated with BS-2 brand oligomer antipyrene-antiseptic

The study found that according to the tests, the mass loss of the average sample was 8,2%, based on the results of research of fireproof properties of wood materials treated with a BS-3 brand oligomer antipyrene-antiseptic. This indicates that fireproof materials fall into group 1 (table 4).

Table 4

Indicators of wood materials treated with BS-3 brand oligomer antipyrene-antiseptic

The data obtained in a practical experiment according to the tables above indicate that the effectiveness of fire resistance of wood materials treated with oligomeric flame retardant-antiseptic brands BS-1, BS-2 and BS-3 belongs to group I.

When treated with a 20% solution of the proposed flame retardant antiseptic of wooden materials, it was found that after deep penetration into their surface layer and drying, the flame retardant remains in the inner layer. As a result of flame exposure to these flammable materials, water forms vapors due to hydroxide groups. Thus, a mechanism based to prevent the continuation of the flame because of reducing oxygen access to the environment.

In experiments when processing wooden materials with a brush and a spray gun, the flame retardant consumption is 0,30 kg/m², and double treatment is required for inclusion in-group 1. This method is mainly recommend for use in buildings and structures where repairs have already been completed and has a service life of 1-3 years.

Processing of wood samples with flame-retardants at a pressure of 1-2 atm. it carried out at a pressure equal to 0,20 kg / m², and the flame retardant consumption is. This method is technologically complex and requires special conditions.

The technology of working together with the fact that soaking in the bath has a relatively low impact on the structure of wooden samples is distinguished by its simplicity and durability. In this bath, the organization of the processing of wooden samples with antipyres is carried out in each building or structure, as well as a high level of processing. In the table below, the effective amount of processing of wood materials with antipyrenes is given (table 5).

Table 5

Effective amount of processing on wooden materials with antipyrene-antiseptic

Wood materials treated with oligomer antipyrene-antiseptics of brands BS-1, BS-2 and BS-3 are 6,5 – 8,2%, according to the mass loss of its fire-resistant property.

During the studies, wood materials were created that are fireproof and biologically stable by processing them into wooden building materials with oligomer antipyrene-antiseptic of the brands BS-1, BS-2 and BS-3. In determining the biological effectiveness of processed wood materials, a pre-existing wood sample was prepared on the basis of GOST 9.048-89, and test experimental work was carried out (table 6).

Table 6

Technical characteristics that characterize the biological efficiency of wood materials

Thus, the results of the research carried out were scientifically proven during practical experiments that oligomer antipyrene-antiseptics, which are present and contain zinc, are highly effective in improving the fire resistance and biological efficiency of wood materials. This in turn indicates the prospects for the production and application of antipiren-antiseptics with boron and zinc content.

References:

1. Nurkulov F.N., Jalilov A.T. Phosphorous-containing oligomeric flame retardants for wood and wood composite materials // V International Conference-School of Chemistry and physicochemistry of oligomers: Collection of abstracts. (Volgograd, June 16, 2015). Moscow Chernogolovka Volgograd. 2015. p. 241.
2. Baxtiyor Shaykulov, Fayzulla Nurkulov, Abdulahat Djalilov / FP-145     Investigation of the main indicators of the fire-retardant coating on an acrylic/ //International scientific and practical conference on the topic: Fundamental and practical aspects of functional polimers// Tashkent, 17-18 march 2023y, 596-598p.
3. Wang, Y.; Kou, X.; Deng, J.; Zhao, J.; Shi, H. Ammonium polyphosphate/expandable graphite/TiO2 blended silica fume-based geopolymer coating for synergistically flame-retarding plywood. Constr. Build. Mater. 2022, 317.
4. Khashkhozheva R.R., Cherkesova R.A., Khashirova S.Yu., Mikitaev A.K. // Materials of the international scientific and practical conference Chemistry: state, prospects of developme. Grozny, 2014. – p. 80.
5. GOST 16363-98
6. GOST 9.048-89.