RU2376329C2 - Raw mixture for making heat insulating objects based on foam plastic - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: mixture contains carbamidoformaldehyde resin, acid hardener, surface active substance, modifying additive and water. The modifying additive is a solution of natural bischofite mineral of formula MgCl₂·6H₂O with density of 1.24-1.40 t/m³.

EFFECT: obtained a raw mixture provides for fluidity of the foam mass, its resistance to pathogenic flora, reduces percentage of shrinking deformation and bulk weight, increases resistance to combustion, reduces release of toxic substances.

1 cl, 3 ex, 11 tbl, 1 dwg

Description

The invention relates to inorganic chemistry and can be used for the manufacture of foam-based materials for thermal insulation of building structures, cabins and installations, as well as for packaging.

A known composition for the production of urea-formaldehyde foam, including urea-formaldehyde resin, an acid hardener, a surfactant and water, in which, in order to increase water and moisture resistance, ultimate compressive strength of the final product, it additionally contains glycerin and distillation residue of triethylene glycol extractant - technical mixture of higher polyglycols with an average mol. m. 360-380 in the following ratio of components, wt.%:

Urea-formaldehyde resin 20-30 Surface-active substance 4-6 Acid Hardener 15-17 Glycerol 0.8-1.1 Technical mixture of higher polyglycols with an average pier. wt. 360-380 0.1-0.4 Water rest

(SU, copyright certificate No. 1168570. A. M. cl ⁴ C08J 9/30, C08L 61/24. Composition for the production of urea-formaldehyde foam / A.I. Zelensky, E.I. Grushova, M.V. Garkusha, E. I. Scherbina (USSR) .- Application No. 3567043 / 23-05. Declared March 21, 1985. Publish. July 23, 1985, Bull. No. 27).

The disadvantages of the described composition in relation to the problem being solved - increasing the fluidity of the raw material mixture for foam and reducing volume shrinkage - include the fact that the technical mixture of higher polyglycols introduced into the composition of the mixture for producing urea-formaldehyde foam reduces the fluidity of the raw mixture. When curing the foam, its initial linear dimensions B × L × H are reduced by 8 percent or more.

Also known is a raw material mixture for the manufacture of heat-insulating products, including urea resin, hardener, phosphogypsum, polystyrene foam and water, in which, in order to increase the compressive strength and frost resistance, it contains ammonium chloride as a hardener, semi-aqueous phosphogypsum as a hardener, and additionally - sulfate liquor - a waste of cellulose production - and perlite sand in the following ratio of components, wt.%:

Carbamide resin 21-50 Ammonium chloride 0.2-0.6 Semi-aquatic phosphogypsum 10-16 Expanded polystyrene 10.8-14.4 Sulphite liquor - a waste of pulp production 9-14 Perlite sand 15-19

(SU, copyright certificate No. 1505909. A1. M. cl ⁴ SB04 26/12. Raw mix for the manufacture of heat-insulating products / B.K. Demidovich, V. B. Kovalevsky (USSR). - Application No. 4231584 / 23-33. Declared April 20, 1987. Publish. September 7, 1089, Bull. No. 33 // Discoveries. Inventions, - 1989. - No. 33).

The disadvantages of the described raw mix in relation to the manufacture of filled foam include high shrinkage during curing, a high degree of fouling of the product surfaces by pathogenic microflora, i.e. low biostability.

There is also known a raw mixture for the manufacture of decorative and decorative building products (options), containing caustic magnesite, sawdust, an aqueous solution of bischofite, in which it additionally contains iodinol, previously dissolved in an aqueous solution of bischofite, in the following ratio of components, ob.ch .:

Bischofite aqueous solution 0.7-1.0 Caustic Magnesite 1.0-1.5 Sawdust 2.0-3.5 Iodinol 0.3-0.8

it additionally includes crystals of the mineral carnallite with a size of from 2 to 10 mm in an amount of 0.25-0.40 ob.ch.

A second variant of a similar raw material mixture for the manufacture of decorative and decorative building products is known, containing caustic magnesite, wood sawdust, an aqueous bischofite solution, in which it additionally contains carnallite mineral crystals with a size of 2 to 10 mm, introduced after caustic magnesite, wood sawdust and water bischofite solution, in the following ratio of components, ob.ch .:

Bischofite aqueous solution 0.7-1.0 Caustic Magnesite 1.0-1.6 Sawdust 2.0-3.6 Carnallite mineral crystals 0.25-0.40

(RU, patent No. 2268247. C1. IPC С04В 28/30 (2006.01), С04В 18/26 (2006.01), Е04F 13/00 (2006.01), A61G 10/02 (2006.01). Raw mix for the manufacture of finishing and decorative building products (options) / G.V.Spirin, V.A. Voytovich, A.A.Spirin (RU) - Application No. 2004117950 / 03. Declared April 16, 2004. Publish. January 20, 2006, Bull. No. 2 // Inventions. Utility models. - 2006. - No. 2).

Introduced into the raw mixes (according to the first and second options), an aqueous solution of the natural mineral bischofite of the formula MgCl ₂ · 6H ₂ O gives balneological qualities to the finishing building products. However, the amount of bischofite mineral introduced is not enough to increase the fluidity of the feed mixture when filling out forms.

Known complex additive for quick-hardening mixture, including water, in which it additionally contains sodium chloride, bischofite and the oligomeric product of the condensation of acetone and formaldehyde - ACF oligomer in the following ratio, wt.%:

Sodium chloride 1.5-3.0 Bischofite 1.5-3.0 ADC oligomer 0.1-0.3 Water rest

(RU, patent No. 2258049. C1. IPC С04В 22/12, С04В 103: 14, С04В 28/00. Complex additive for quick-hardening mix / V.A. Perfilov (RU). - Application No. 2003138159/03. Declared 31.12. 2003. Published on 08/10/2005, Bull. No. 22 // Inventions. Utility models - 2005. - No. 22).

The disadvantages of the described complex additives, despite the declared technical results: increased mobility of the mixture, acceleration of hardening and increased strength in the early stages of natural curing, include low fluidity of mortar mortar due to the low content of a solution of the natural mineral bischofite of the formula MgCl ₂ · 6H ₂ O (practically in solution - traces of the components of the mineral bischofite).

A known method of producing a raw material mixture for the manufacture of decorative and decorative building products (options), including mixing caustic magnesite with sawdust, followed by moistening the mass with an aqueous solution of bischofite, final mixing, which is introduced into the mixture in an amount of 0.3-0.6 vol .h. iodinol, pre-mixed with an aqueous solution of bischofite; injected into the mixture in an amount of 0.25-0.4 vol.h. Carnallite mineral crystals with a size of 2 to 10 mm, which are added immediately after the final mixing of the main components of the mixture and mixed for no more than 1.5 minutes.

A second variant of the method for producing a raw mixture for the manufacture of decorative and decorative building products is known, including mixing caustic magnesite with wood sawdust, followed by moistening the mass with an aqueous bischofite solution, final mixing, in which 0.25-0.40 vol. hours crystals of the carnallite mineral with a size of 2 to 10 mm, added immediately after the final mixing of the main components of the mixture, and stirred for no more than 1.5 minutes (RU, patent No. 2276117. C2. IPC С04В 28/30 (2006.01), С04В 18 / 26 (2006.01), E04F 13/00 (2006.01), A61G 10/02 (2006.01). A method of producing a raw material mixture for the manufacture of decorative and decorative building products (options) / GV Spirin (RU), V.A Voitovich (RU), AAspirin (RU) .- Application No. 2004117952/03. Submitted June 16, 2004. Published May 10, 2006, Bull. No. 13 // Inventions. Utility models. - 2006. - No. 13).

The disadvantage of the described methods for producing raw mixes for the manufacture of decorative and decorative building products in relation to the technical problem to be solved is, despite the presence of an aqueous solution of the bischofite mineral, low fluidity during mold filling.

Also known is a composition for the manufacture of heat-insulating material, including a polymer, an acid hardener, a filler, a surfactant, and water, in which it additionally contains a plasticizer, and as a polymer, a urea and formaldehyde polycondensate product stabilized with ammonia, or a urea and formaldehyde polycondensate product modified with vinacryl and stabilized with ammonia, or a urea-formaldehyde polycondensate product modified with vinacryl and stabilized with tetrab sodium sulfate, in the following ratio of ingredients, wt.%:

Polymer 20-65 Surface-active substance 1-5 Acid Hardener 1-5 Filler 5-40 Plasticizer 0.2-5.0 Water rest

as a surfactant, it contains a mixture of sodium or calcium salts of fatty acids of a fraction of C ₁₉ -C ₂₅ and sodium or triethylamine salts of alkylsulfuric acids of a fraction of C ₁₀ -C ₁₃ in the following ratio of ingredients, wt.%:

Sodium or triethanolamine salts of alkylsulfuric acids fraction C ₁₀ -C ₁₃ 60-70

or a mixture of sodium or calcium salts of fatty acids of a fraction of C ₁₉ -C ₂₅ and sodium or triethanolamine salts of sulfates of alkylamides of synthetic fatty acids of a fraction of C ₁₀ -C ₁₆ in the following ratio of ingredients, wt.%:

Sodium or calcium salts of fatty acids fraction C ₁₉ -C ₂₅ 10-30 Sodium or triethanolamine salts of alkyl sulfates primary fats of the alcohol fraction C ₁₀ -C ₁₃ 30-50

or a mixture of sodium or calcium salts of fatty acids of fraction C ₁₉ -C ₂₅ and sodium or triethylamine salts of alkyl sulfuric acids of fraction C ₁₀ -C ₁₆ and sodium or triethanolamine salts of sulfates of synthetic monoethanolamides of synthetic fatty acids of fraction C ₁₂ -C ₁₆ in the following ratio of ingredients, wt. .%:

Sodium or calcium salts of fatty acids fraction C ₁₉ -C ₂₅ 10-30 Sodium or triethanolamine salts of alkylsulfuric acids fraction C ₁₀ - C ₁₃ 30-50 Sodium or triethanolamine salts of monoethanolamide sulfates
synthetic fatty acids fraction C ₁₂ -C ₁₆ 30-50

or a mixture of sodium or calcium salts of fatty acids of a fraction of C ₁₉ - C ₂₅ and sodium or triethylamine salts of alkyl sulfates of primary fatty alcohols of a fraction of C ₁₀ -C ₁₃ and sodium fluoroalkyl sulfates based on α-olefins of a fraction of 100-320 ° C C _n H _{2n + 1} CH (CH ₃ ) OSO ₃ Na (n = 6-16) and sodium alkylbenzosulfonates based on kerosene C _n H _{2n + 1} C ₆ H ₄ SO ₃ Na (n = 12-18) in the following ratio of ingredients, wt.%:

Sodium or calcium salts of fatty acids fraction C ₁₉ -C ₂₅ 10-30 Sodium or triethanolamine salts of alkyl sulphates of primary fats of the alcohol fraction C ₁₀ -C ₁₃ 45-60 Sodium fluoroalkyl sulfates based on α-olefins fraction 100-320 ° С C _n H _{2n + 1} СН (СН ₃ ) OSO ₃ Na (n = 6-16) 5-20 Sodium alkylbenzosulfonates based on kerosene C _n H _{2n + 1} C ₆ H ₄ SO ₃ Na (n = 12) 15-20

as a filler, it contains expanded perlite sand, or porous sands based on slag, or gypsum, or phosphogypsum, or paper sludge, or expanded clay, or wood chips, sawdust, or sodium silicate, or their binary or triple mixtures in mass ratio of ingredients 1: 1;

as a plasticizer, it contains polyvinyl alcohol or a polyvinyl acetate dispersion, or rubber based latexes, or starch and its derivatives, or dibutyl phthalate, or bustylate, or their binary or ternary mixtures in a mass ratio of ingredients of 1: 1; it additionally contains flame retardant ammonium phosphate, or phosphate or bromide salts of polyamines, or chloroparaffins, or hexachlorobenzene, or tetrabromohydroxyphenyl propane, or aluminum hydroxide, or zinc borate, or their binary or ternary mixtures in the ratio of ingredients 1: 1 in an amount of 0.5: 1 -1.0 wt.% Due to water; it additionally contains a mixture of dicarboxylic acids of fraction C ₂ -C ₆ in an amount of 0.3-1.5 wt.% due to water (RU, patent No. 2055820. C1. IPC ⁶ C04 B 26/14. Composition for the manufacture of thermal insulation material / V.P. Gerasimenya, I.N. Zhukov, A.I. Kozlovsky, L.A. Soboley (RU) - Application No. 94017294/26. Declared May 24, 1994. Publish. March 10, 1996).

The disadvantages of the described composition for the manufacture of heat-insulating material include a high percentage (more than 5%) of volumetric shrinkage of freshly prepared foam mass and its low fluidity when filling cavities, voids and inter-wall partitions.

Also known is a composition for the manufacture of heat-insulating material, including urea-formaldehyde resin, an acid hardener, a filler and a surfactant, in which, in order to improve thermal insulation properties and reduce the emission of harmful substances into the environment, it additionally contains urea and sodium silicate in the following ratio of components, wt. %;

Urea-formaldehyde resin 40.3-60.7 Acid Hardener 4-10 Filler 18-28 Surfactant 0.3-0.7 Urea 12-14 Sodium silicate 5-7

(SU, patent No. 1834870. A3. M. class. C04 B 26/12, 38/08. Composition for the manufacture of heat-insulating material / I.Z. Akhmetshina (USSR). - Application No. 4928827/33. Declared April 23, 1991. Published on August 15, 1993. Bull. No. 30 // Discoveries. Inventions. - 1993. - No. 30).

The disadvantages of the described composition for the manufacture of thermal insulation material include low fluidity of freshly prepared foam mass and a high percentage of volume shrinkage.

In addition to those described, a foam composition is known including urea-formaldehyde resin, an aqueous solution of phosphoric or hydrochloric acid, a surfactant based on a mixture of sodium salts of sulfate esters of secondary alcohols containing 6-16 carbon atoms, glycerol, dihydric alcohol and water, in which , in order to increase the compressive strength of the foam, it contains 1,2-ethanediol and, additionally, 2-tetrahydrofurylmethanol in the following ratio of components, wt.%:

Urea-formaldehyde resin 20-30 Phosphoric or hydrochloric acid (5% aqueous solution) 15-17 Surface-active substance 4-6 Glycerol 1-1.8 1,2-ethanediol 0.1-0.3 2 - tetrahydrofurylmethanol 0.05-0.20 Water rest

(SU, copyright certificate No. ………………………………).

The disadvantages of the described foam composition, despite the similarity of some of the components in the proposed raw material mixture for the manufacture of heat-insulating products, include low fluidity of the mixture and a high percentage of volumetric shrinkage during curing.

A known foam composition comprising urea-formaldehyde resin, a surfactant, an acid hardener, glycerin and water, in which, in order to increase the compressive strength of the final product, it contains a surfactant selected from the group: sodium salt of tridecyl alcohol, sodium β-alkyl sulfonates based on α-olefins of a fraction of 100-320 ° C, an acid hardener selected from the group: phosphoric or hydrochloric acid, and additionally an aliphatic epoxy resin based on diethylene and triethylene glycol and the following component ratio, wt.%:

Urea-formaldehyde resin 20-30 Specified Surfactant substance 4-6 Specified Acid Hardener 15-17 Glycerol 0.8-2.1 Aliphatic epoxy resin on based on diethylene or triethylene glycol 0.1-0.4 Water rest

(SU, copyright certificate No. A1. M. class. Composition for polystyrene / EI Grushova, EI Scherbina (USSR). - Application No. 3805997 / 23-05. Declared 10.29.1984).

The disadvantages of the described composition of the foam include high shrinkage of the foam and low fluidity of the raw material mixture when filling the cavities of building structures.

A known composition for producing a foam containing urea-formaldehyde resin, a surfactant, phosphoric acid, water and a modifier, in which as a modifier it contains a carbonaceous UGM modifier with a content of humic acids 60-85% in the following ratio of components, wt.%:

Urea-formaldehyde resin 20-35 Surface-active substance 0.4-0.5 Orthophosphoric acid 2.0-3.0 Coal modifier with the content of humic acids 60-85% 0.4-0.6 Water rest

RU, patent No. 2074206. C1. MPK C08L 61/24, C08J 9/30. Composition for polystyrene / B.V. Levinsky (RU). - Application No. 94003554/04. Declared 02/03/1994. Publ. 02/27/1997).

The disadvantages of the described composition for the production of foam include low fluidity of the mixture, high shrinkage of the foam, low strength and high probability of populating micropores with pathogenic microflora.

Known foam obtained from a composition containing a liquid resin based on urea and / or melamine and formaldehyde, an organic polyisocyanate, an amine catalyst and an organosilicon stabilizer, in which a resin based on urea and / or melamine and formaldehyde of a cyclic structure containing 3-23% of the damage cycles and / or 3-35% of the triazine cycles, 61.5-75.2% concentration and additionally used three (2-chloroethyl) phosphate or bis (β-chloroethyl) vinyl phosphate in the following ratio of components, m s.ch:

Urea and / or melamine based liquid resin and formaldehyde cyclochain structure, containing 3-23% of uronic and / or 3-35% of triazine cycles, 61.5-75.2% concentration 50-250 Organic Polyisocyanate 50-100 Amine catalyst 1-15 Silicon Organic Stabilizer 1-30 Tri (β-chloroethyl) phosphate or bis (β-chloroethyl) vinyl phosphate 10-50

it is obtained from a composition additionally containing a modifying additive in an amount of 5-50 parts by weight; phenols, aliphatic polyhydric alcohols, furfuryl alcohol were used as a modifying additive; the foam is obtained from a composition additionally containing a filler in an amount of 5-50 parts by weight; as the filler used inorganic and / or organic filler (RU, patent No. 2058338. C1. IPC ⁶ C08G 18/54, C08G 101: 00, C08J 9/02 / Polyfoam / N.M. Romanov, S.I. Sokolova, A.N. Pukhovitskaya, L.N. Smirnova (RU) .- Application No.93003854 / 04. Declared January 26, 1993. Publish. April 20, 1996).

The disadvantages of the described foam include unacceptably high emissions of formaldehyde, high density of the foam, as well as low water resistance and heat resistance of the insulating mass.

A known composition for producing foam and a method for its production. A composition for producing a foam comprising a urea-formaldehyde resin and a blowing agent containing a surfactant, phosphoric acid and water, in which it additionally contains resorcinol and lignosulfonates pre-modified with urea in an amount of 3-6 parts by weight for 10 parts by weight liquid lignosulfonates, for 0.5-2.5 hours, at 30-60 ° C in the following ratio of components, parts by weight:

Urea-formaldehyde resin 37.31-47.48 Modified Lignosulfonates 2.47-12.19 Resorcinol 0.05-0.50 Surface-active substance 1,50-2,50 Orthophosphoric acid 1,50-2,50 Water 45.00-47.00

A method of producing a foam by dismounting and foaming a composition, comprising a urea-formaldehyde resin and a foaming agent containing a surfactant, phosphoric acid and water, in a stream of compressed air, in which the composition used to produce the foam according to claim 1 (RU, patent No. 2091407. C1. IPC C08J 9/06, C08J 9/30, C08L 61/24 Composition for polystyrene foam and a method for its production / N.V. Genbutis, V. B. Semenova, E. A. Maslakova (RU) - Application No. 92011375/04. Declared December 14, 1992. Publish. September 27, 1997).

The disadvantages of the described composition for producing foam, adopted as the closest analogue, are the low fluidity of the foam composition and the large amount of shrinkage of the foam during curing.

The essence of the claimed invention is as follows.

The problem to which the claimed invention is directed is to reduce the degree of horizontal shrinkage of the heat-insulating foam.

The technical result is an increase in fluidity, resistance of the foam to pathogenic microflora, a decrease in shrinkage deformations, a decrease in bulk density, an increase in resistance to fire, a decrease in the degree of release of toxic substances, including and formaldehyde.

The specified technical result is achieved by the fact that in the known raw material mixture for the manufacture of heat-insulating products, mainly from foam, including urea-formaldehyde resin, an acid hardener, a surfactant, a modifying additive and water, according to the invention it contains a solution of a natural mineral bischofite of the formula MgCl ₂ · 6H ₂ O with a density of 1.24 ... 1.40 t / m ³ in the following ratio of components, wt.%:

Urea-formaldehyde resin 20-30 Surface-active substance 4-6 Acid Hardener 13-19 Modifying additive 8-16 Water rest

The invention is illustrated by the technological scheme, tabular materials and examples.

Information confirming the possibility of implementing the claimed invention are as follows.

The raw material mixture for the manufacture of heat-insulating products, mainly from foam, contains a urea-formaldehyde resin, an acid hardener, a surfactant, a modifying additive and water.

In the described raw material mixture, a urea-formaldehyde resin manufactured in accordance with the requirements of GOST 14231-78 or TU 6000-5763450-112-90 is used as a binder. The physicochemical characteristics of the urea-formaldehyde resin brand KF-MT (PP) of the Volgograd branch of OAO Khimprom are shown in table 1. The limiting values of the described component in the manufacture of similar heat-insulating materials are given in table 2.

As the acid hardener, mono- and dibasic low molecular weight organic acids are used, such as oxalic according to GOST 22180-76. citric acid in accordance with GOST 908-79E, malic acid in accordance with GOST 6341-75, inorganic acids - phosphoric acid in accordance with GOST 10678-76 or GOST 6552-80, hydrochloric acid in accordance with GOST 857-78, rust soil converter (GPR) in accordance with TU 6-09 -20-144-88, washing solution (ADS) according to TU - 6-02-13-72-8 8 and others. The limiting values of a 5% phosphoric acid solution H ₃ PO ₄ as an acidic hardener of the foam are given in table 2.

As a surfactant, they are used in similar compositions for the manufacture of thermal insulation material or diproxamine according to TU 6-14-614-82, or OP-10 according to GOST 8433-81, or proxamine NP-71 according to TU 6-14- 1990-75, or proxamine NP-71 according to TU 6-14-1990-75, or sulfonol according to TU 6-01-862-75, or sulfonol according to TU 6-01-862-75, or polyethylene glycol according to TU 6-06 -C147.

As foaming agents for the production of urea foams, products AVO-1, ABO-2, PO-1 (GOST 6948-81), Progress, PO-3A, etc. are used.

Noteworthy as a surfactant is alkylbenzene sulfonic acid (ABSFK) according to TU 2481-036-04689375-95, commercially available from the Volgograd branch of Khimprom OJSC. Alkylbenzenesulfonic acid is obtained by sulfonation of linear alkylbenzene (TU 2414-038-046893 75-95) and is used as a starting product for the production of alkylbenzenesulfonates - components of detergents. In appearance, alkylbenzenesulfonic acid is a viscous brown liquid. The formula of ABSFC is RC ₆ H ₄ SO ₃ H, R = C ₁₀ -C _{14. The} technical characteristics of ABSSC grades A, B and C are given in table 3. The limiting values of surfactants in the composition of the insulating material are presented by the numerical data in table 2.

As a modifying additive used natural mineral bishofit (bishofit), mined in the fields of the Volgograd region. Explored reserves of bischofite mineral for 2007 in the Lower Volga region, there are up to 100 billion tons. Bischofite mineral is extracted from the depths of 200-800 m by the method of underground dissolution. The mineral is hygroscopic. Upon dissolution, a brine with a density of up to 1.42 t / m ^{3 is formed} . The brine also contains paraffin-containing components. The bischofite mineral dissolves in water at any temperature. Table 4 presents the composition of samples of bischofite leach brine mined in the fields of the Volgograd region. Table 5 shows the analysis of samples of bischofite leach brines, and table 6 shows the analysis of samples of bischofite brine and the content of macro- and microelements in them. Table 7 describes the composition of the bischofite brine of the formula MgCl ₂ · 6H ₂ O extracted in the city of Volgograd. In the data presented, the density of the brine is 1.2444-1.3051 t / m ³ , and the mineralization of the solution is 281.35-331.95 g / l. The main component of the solution is MgCl ₂ - 267.2-325.3 g / kg.

In the manufacture of prototypes of the foam in the experiments, distilled water was used in accordance with GOST 6709-72, and in the production of heat-insulating material, water was used that meets the requirements of the standard - GOST 2492-81.

Example 1. The foam is obtained as follows. Urea-formaldehyde resin of the brand KF-MT (PP) is poured into a container 1 through a fine mesh (see diagram) in the form of a suspension from white to light yellow in color. On the tank 1, a scale 2 is made as a level gauge for visual assessment of the state and volume of the resin. In the lower part of the tank 1 there is a two-way valve 3 with a weight batcher. All introduced ingredients in the mixture are introduced according to the mass values.

Pour water in accordance with GOST 2402-81 in a container 4. The water level in the tank 4 is monitored on a scale of 5. In the lower part of the tank 4 there is a two-way valve 6 with a weight batcher, a tubular electric heater (TEN) with a power of 1 kW and a thermometer.

In a container 7, a brine of the natural mineral bischofite of the formula MgCl ₂ · 6Н ₂ О with a density of 1.2-1.4 t / m ^{3 is} poured (delivery status from the field). The brine level in the tank 7 is monitored on a scale 8. Under the tank 7, a two-way valve 9 with a weight batcher is mounted.

Tanks 1, 4 and 7 are mounted above the chamber 10 for mixing urea-formaldehyde resin with bischofite brine and water until a homogeneous mixture is formed. Portions of urea-formaldehyde resin, bischofite and water correspond to the ingredients in mass fractions (in%), are given in table 8. A two-way valve 11 in the bottom of the mixing chamber 10 is provided for preventive maintenance at the end of each shift and should be set to the “Closed” position. A two-way valve 12 in the bottom of the mixing chamber 10 is connected by a pipe 13 to a pump 14. The pump 14 is connected by a three-way valve 15 to a pipe 16 for supplying a recycle mixture to the mixing chamber 10. Before the three-way valve 15 after the pump 14, a pressure gauge 17 is mounted on the pipeline to control the pressure of the working fluid. A pump 14 is mounted below the mixing chamber 10.

When the electric drive of the pump 14 is turned on, the components for mixing from the chamber 10 are repeatedly circulated through pipelines 13 and 16 with open taps 12 and 15 from the chamber 10 and back for 3-5 minutes, reaching an equilibrium state with a temperature not lower than + 30 ° С. This ensures uniform mixing of the resin with bischofite and water, bringing the percentage of resin in the water to the desired values.

Simultaneously with these works, sodium alkyl benzosulfonate is poured into the container 18. The level of the latter in the tank 18 is set on a scale of 19. Under the tank 18, a two-way valve 20 with a weight batcher is mounted. Water is filled in a container 21 that meets the requirements of GOST 2402-81. The water level in the tank 21 is monitored on a scale of 22. A two-way valve 23 with a weight batcher is mounted under the tank 21. Orthophosphoric acid H ₃ PO _{4 is} poured into the tank 24 according to GOST 6552-80. The acid level in the tank 25 is monitored on a scale of 25. The release of acid H ₃ PO ₄ from the tank 25 is carried out by a two-way valve 26 with a weight dispenser.

A component of a blowing agent is poured into a container 27 — a brine of the natural mineral bischofite of the formula MgCl ₂ · 6H ₂ O with a density of 1.2-1.4 t / m ³ and meeting the requirements of GOST 7759-73. The ratio of ingredients in mass fractions for the formation of foamed mass is shown in table 8. To obtain a homogeneous mass of the components of the foam under the containers 18, 21, 24 and 27, a chamber 30 is installed for mixing the components of the foam. Two-way valves 31 and 32 are mounted at the bottom of the foam component mixing chamber 30. A two-way valve 32 is hydraulically connected to a pump 34 by a pipe 33. A pump 34 is connected through a three-way valve 35 to a pipe 36 for recycling the solutions that are components of the foam. When the pump 34 is operating, the liquid components for foam formation are intensively mixed for 3-4 minutes to evenly distribute the components in the entire volume of the working solution. The operation of the pump 34 is controlled by the readings of the pressure gauge 37.

When mixing KF-MT resin, water and bischofite in the mixing chamber 10 and sodium alkylbenzenesulfonate or ABSFK, phosphoric acid, water and bischofite in the chamber 30 are completed, three-way valves 15 and 35 are put into position for supplying the mixtures to pipelines 38 and 39 through the check valves 40 and 41 into the cavity of the foam generator 42. The cavity of the foam generator 42 is pneumatically connected by means of a flexible sleeve 43 through a check valve 44 to a compressor 45 and a receiver 46 of compressed air. The air pressure in the pneumatic network is controlled by a manometer 48. The foam generator 42 is connected by a flexible transparent sleeve 49 to a bell 50 to supply foamed heat-insulating material to the inter-wall cavities when warming objects under construction.

When the two-way valve 29 is closed, the calculated dose of bischofite brine from the tank 7 completely enters the mixing chamber 10. Table 9 shows the physicotechnical and environmental properties of the heat-insulating material from the components shown in table 8, and the entire volume of bischofite brine is introduced in different mass fractions: 4, 6, 8, 10, 12, 14, 16, 18 and 20 wt.% urea-formaldehyde resin. Foam samples were taken as control, where bischofite was not added (see columns 11 in tables 8 and 9).

The data in table 9 indicate in favor of introducing into the raw material mixture for the manufacture of heat-insulating products in the form of filling polystyrene a modifying additive - brine of the natural mineral bischofite in the indicated mass fractions.

Example 2. The foam is obtained as follows. The entire batch sample of the natural mineral brine bischofite of the formula MgCl ₂ · 6H ₂ O is loaded into a container 27 and fed through a two-way valve 29 with a weighing batcher into the foam mixing chamber 30. The two-way valve 9 under the tank 7 is set to the "Closed" position.

With the pump 34, the liquid components from the containers 18, 21, 24, and 27, when pumped from the mixing chamber 30, are brought into equilibrium when the liquid circulates from the chamber 30 through the pump 34 through pipelines 33 and 36 for 3-4 minutes. With the three-way valves 15 and 35 open, the dissolved resin from the chamber 10 and the foaming components from the chamber 30 are passed through pipelines 38 and 39 to the foam generator 42, where stable air cavities are created under excess air pressure in the foam mass. Air foam through a flexible transparent sleeve 49 is fed into the bell 50, and to them in the cavity in the insulated walls. As in example 1, to compare the obtained test results of the foam cups with a cross section of 100 × 100 × 100 mm, the ingredients remained the same and in the same mass fractions (see table 8).

The physicomechanical and environmental properties of the heat-insulating material when applying a modifying additive — the brine of the natural mineral bischofite to the foam-forming components — are presented in Table 10. For the control, samples of penoizol without the use of bischofite were selected. The data presented show the appropriateness of introducing an additive in the form of a brine of the natural mineral bischofite into the raw material mixture for the manufacture of filling foam.

Example 3. The foam is prepared as follows. Bischofite brine with a density of 1.24-1.40 t / m ^{3 is} poured into containers 7 and 28. The bischofite density is checked by a hydrometer. The first half of the mass fraction of bischofite brine is discharged into the urea-formaldehyde resin mixing chamber 10, and the second half of the mass fraction of bischofite brine is sent from the tank 28 to the foam component mixing chamber 30. Using the working pumps 14 and 34, the bischofite brine is evenly distributed in the solutions of the chambers 10 and 30. Next, the well-mixed ingredients are fed through the three-way valves 15 and 35 and with the compressors 45 and pumps 15 and 35 into the foam generator 42. The resulting movable mass is squeezed out of the foam generator 42 by air flow in a flexible transparent sleeve 49 and a bell 50 fits into the cavity of the walls. Physico-technical and environmental properties of the insulating material obtained by the described method are shown in table 11.

The above information confirms the legitimacy of the introduction of the brine of the natural mineral bischofite of the formula MgCl ₂ · 6H ₂ O in the raw material mixture for the manufacture of insulating products.

Claims (1)

The raw material mixture for the manufacture of thermal insulation products based on foam, including urea-formaldehyde resin, a surfactant, an acid hardener, water and a modifying additive - a solution of the natural mineral bischofite of the formula MgCl ₂ · 6H ₂ O with a density of 1.24 ... 1.40 t / m ³ , in the following ratio of components, wt.%:
Urea-formaldehyde resin 20-30 Surface-active substance 4-6 Acid Hardener 13-19 Modifying additive 8-16 Water Rest

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