RU2486054C1 - Composition for making fire-resistant fibreboard - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to production of building materials. Disclosed is a composition which contains a wood-fibre mass, a hydrophobic emulsion in form of paraffin and sulphuric acid and expanded vermiculite. The expanded vermiculite has particle size of 0.01-0.4 mm.

EFFECT: said composition enables to obtain fibreboard having fire-resistant properties.

2 tbl, 5 ex

Description

The invention relates to the field of building materials and can be used in the construction of buildings, sea and river vessels, in aviation, in the automotive industry.

The composition of the raw material mixture is known, including expanded vermiculite (25-84%), water glass (14-55%) and an additive for the production of mica plastic (2-20 wt.%) Containing organosilicon and other varnishes (for example, KO-901, KO -914) [SU 1451127, IPC С04В 28/34, 28/26, 1989].

The disadvantage of this mixture is that organosilicon and other varnishes emit harmful substances during combustion. In addition, there is no real raw material base for mica waste containing the varnishes mentioned above, since the production volume of such mica is only a few tens of tons per year and, accordingly, the annual amount of waste will not exceed 5-10 tons, which is not enough for the production of fireproof building materials.

Known raw material composition of the charge for the manufacture (with heating the mixture to 600 ° C) of highly porous ceramics based on liquid glass and vermiculite, including expanded vermiculite and ground slag of metallurgical industries in the following ratio of components, wt.%: Fraction F1 from the original vermiculite with a particle size of 1 -10 mm - the base (60-30); fraction F2 from ground vermiculite with a particle size of 0.15 to 0.40 from the fraction F1 - 12-15; fraction F3 from ground vermiculite with a particle size of 0.15 to 0.40 from the fraction F2 - 2.5-7.5; fraction F4, consisting of particles of ground slag of metallurgical industries with a particle size of from 0.15 to 0.40 from fraction F3 in an amount of from 2.5-15; liquid glass 13-20; curing agent - 10-12.5.

Characteristic: density 180-220 kg / m ³ , thermal conductivity 0.05-0.07 W / (m · K) [RF Patent 2092467, С04В 38 / 08.1997].

The disadvantage of this composition is the impossibility of its use as a flame retardant and structural material due to the high porosity.

A known composition for producing wood-fiber boards (Fibreboard), including, wt.%: Wood fiber 93-99.7, hydrophobic additive, including oil paraffins 0.1-2.5 and precipitant in the form of mineral acids 0.2-4 5 (including sulfuric acid) [RF Patent 2186807, C08L 97/02, B27N 3/04].

A disadvantage of the known composition is the high fire hazard obtained from it fiberboard.

The invention solves the problem of developing a composition for producing fireproof fiberboards.

The technical result of the invention is the development of a composition for the production of fireproof fiberboards.

The specified technical result is achieved in that the composition for producing fire-retardant wood-fiber boards, including wood-fiber pulp, a hydrophobic emulsion containing oil paraffins and a precipitating agent - sulfuric acid, additionally contains expanded vermiculite in the following ratio of components,%

Pulp 58-78 Expanded Vermiculite 10-30 Paraffin 8-12 Sulphuric acid 0.8-1.2

while the expanded vermiculite has a particle size of 0.01-0.40 mm.

The particle size of the expanded vermiculite for introduction into the composition is selected empirically. The use of particles with sizes greater than 0.4 mm leads to a deterioration in the physical and mechanical properties of the finished product, and less than 0.01 mm is not advisable to use.

The use of expanded vermiculite with a particle size of 0.01-0.4 mm allows the mineral to be evenly distributed over the entire volume of the plate, thereby increasing its flame retardant properties while maintaining the basic physical and mechanical properties at the level of GOST 4598-86.

Expanded vermiculite is a loose, light, highly porous material, with a characteristic scaly structure, odorless. Vermiculite in the expanded state after removal of hydrated water has a density of 80 to 150 kg / m ³ and is an excellent basis for molding materials of various properties from it.

The use of vermiculite in the composition for the production of fiberboards can reduce their fire hazard and improve the performance of fiberboards. Its use for the production of fiberboard in order to reduce fire safety is not known.

Example 1

To prepare the composition, grinding of vermiculite is carried out on a grinding mill operating by the dry grinding method.

A suspension of wood pulp containing 220 g a.s. (78%), 2.46 g of paraffin (11.2%) are added, then 0.18 g (0.8%) of the precipitating agent - sulfuric acid with a concentration of 98%, and 22 g (10%) of crushed expanded vermiculite with particle sizes 0.4 mm.

The mixture is mixed, molded and pressed in a hot press.

Examples 2-5 are similar to example 1, data on the composition are shown in table 1.

Table 1 Components Composition 1 Composition 2 Composition 3 Composition 4 Composition 5 Wood-fiber mass,% 78 73 68 63 58 Expanded vermiculite,% 10 fifteen twenty 25 thirty Paraffin,% 11.2 11.1 eleven 10.9 10.8 Sulfuric acid 98%,% 0.8 0.9 one 1,1 1,2 Particle sizes of expanded vermiculite, mm 0.4 0.3 0.2 0.1 0.01

The tests of fiberboard with expanded vermiculite were carried out at the OTM installation according to the method of experimental determination of the group of slow-burning and combustible solids and materials GOST 12.1.044.-89 “Fire and explosion hazard of substances and materials. The nomenclature of indicators and methods for their determination. " The decrease in the combustibility of the slabs is shown for each example in table 2.

table 2 Structure Dt _max Dm,% F Composition 1 59.5 58.2 more than 4 min Composition 2 58.7 57.9 Composition 3 57.6 56.1 Composition 4 56.2 53.0 Composition 5 55.8 50,0 Note: Dt _max - the maximum temperature increment of the gaseous products of combustion, Dm - the loss of mass of the sample, f - the time to reach the maximum temperature of the gaseous products of combustion

As can be seen from the data in table 2, the use of vermiculite in the composition for the production of wood-fiber boards can reduce their fire hazard, and improve the operational characteristics of wood-fiber boards

Information sources

1. RF patent 2186807, C08L 97/02, B27N 3/04.

2. Copyright certificate 1451127, С04В 28/34, 28/26, 1989.

3. Copyright certificate 867911, С04В 43/00, 1981

4. RF patent 2092467, С04В 38/08, 1997.

Claims (1)

Composition for producing fire-retardant wood-fiber boards, including wood-fiber pulp, hydrophobic emulsion in the form of paraffin and sulfuric acid, characterized in that it additionally contains expanded vermiculite in the following ratio,%:
Pulp 58-78 Expanded Vermiculite 10-30 Paraffin 8-12 Sulphuric acid 0.8-1.2
wherein the expanded vermiculite has a particle size of 0.010-0.4 mm.