CS198427B1 - Manufacturing process of expanded additived urea-formaldehyde materials - Google Patents

Description

The present invention relates to the production of lightweight urea-formaldehyde compositions for reduced heat and sound insulation with reduced flammability and reduced formaldehyde release, wherein the foaming of aqueous solutions of the molar-formaldehyde condensation products with inorganic and organic fillers and granulated ammonium salts, prepared by polymerization, is catalyzed by the action of acids, salts and ureafoefates.

By combining plastics with inorganic additives, new insulating materials are obtained which are characterized by low weight, good chemical resistance to certain aggressive substances, different mechanical properties, which allow different aesthetic and functional modifications. However, mass application is often hampered by inadequate fire safety, and therefore the treatment of polymeric materials with fire retardants or the incorporation of these insulating materials into components limiting the spread of fire is used. Heterogeneous systems with an organic binder and an inorganic or inorganic-organic filler component are increasingly being used. Different production processes follow the preparation of insulating materials directly during molding based on foam polystyrene, epoxides with flame retardants directly in the press between the metal sheets. violet is used to shape unsaturated polyester resins filled with foam glass granules, glass fibers directly into sandwich panels, or polyurethane foams with inorganic additives are applied. Attention is paid to 1 'lightweight additivated polymer systems that have good processing, shaping

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42ββ 427 and rapid curing. For use in construction, it is important to suppress their flammability, reduce water vapor permeability and moisture, and therefore, for profiles cut from blocks, additional protection and surface treatment are often required. Processes using expanded perlite in combination with aminoplasts, phenolplastics and fibrous materials are being developed, whereby building elements with reduced flammability are surface-enhanced by the use of dispersions, sheathed aluminum sheets, tar board, and the like.

An important group of insulating materials are the cured 1-lightened aminoeldehyde condensation products containing inorganic and organic fillers. The most evident developments, also for economic reasons, were light urea-formaldehyde resin compositions which, like other aminoplasts, are characterized by reduced flammability due to high nitrogen content.

In addition to expanded perlite, for the sound and heat-insulating materials based on urea-formaldehyde resins, saler fillers such as asbestos, keramzite, glass fibers and other inorganic materials are used. As a filler of lightweight urea-formaldehyde materials, polystyrene foam, polyurethane foam, cellulose, sawdust and other waste organic materials can be used. Processes for modifying urea-formaldehyde lightened materials by polyacrylates, epoxy, casein-formaldehyde, phenol-formaldehyde resins, and other polymers are also utilized. However, these organic additive components increase the flammability of urea-formaldehyde insulating materials. A further disadvantage of the aminoaldehyde resins and the release of formaldehyde, thereby limiting the application of these bottled materials in construction. The aminoplast foams used for thermal insulation are foamed in the compositions of aminoaldehyde low molecular weight condensates with inorganic and organic components by the action of surfactants and are usually cured by inorganic or organic acids or salts thereof. These compounds increase the corrosive effect of cured, expanded aminoplasts in contact with metallic structural materials. Some inorganic flame retardants and some compounds added to reduce the free formaldehyde content also increase the corrosivity of the aminoaldehyde resins to be treated. a more violent disadvantage is that when water-soluble inorganic additives are used, aa reduces the stability of the foamed aminoplast systems before curing, thereby preventing the preparation of the bottled materials and the low bulk density. Insulating materials based on foamed urea-formaldehyde resins are known in the production of which foaming is effected by alkali metal hydrolyzates of keratin acting as surfactants in the mechanical foaming of urea-formaldehyde condensates with added components and catalysts. These hydrolyzed eu polypeptides in the insulating materials are a breeding ground for the development of microorganisms, which is undesirable in building blocks that are not to be attacked by microorganisms.

The present invention overcomes some of the above drawbacks of insulated materials based on additive urea-formaldehyde resins. SUMMARY OF THE INVENTION The present invention is directed to a process for the manufacture of bottled, additive urea-formaldehyde materials with inorganic and organic additives having reduced flammability and reduced formaldehyde release, which is achieved by providing a solution containing 30 to 80 wt. 0.2 to 12 wt. parts of organic or inorganic acids or their salts a) or urea-phosphate based on urea

198 427 and phosphoric acid in a molar ratio of 1.5 to 0.6 after addition of 0.1 to 6 wt. parts by weight of the surfactant is foamed to eight to ten times the volume, and 45 to 180 wt. % by weight of an aqueous solution of urea-formaldehyde condensation product having a dry matter content of 55 to 70 wt. and 5 to 15 wt. parts of ammonium salts impregnated with polymeric substances which protect these salts from being dissolved in the aqueous phase and 15 to 50 wt. parts of powdered expanded perlite and 6 to 18 wt. parts by weight of polystyrene or polyurethane foam and 5 to 15 wt. parts of inorganic and organic additives to the consistency of the malleable mass and after homogenization, the material is introduced into a mold and allowed to cure and dry within a temperature range of 40 to 120 ° C.

Ureafoaphate, alone or in admixture with inorganic or organic acids or salts thereof, acts as a curing catalyst for the urea-formaldehyde condensate, reducing the flammability of the insulating material, which exhibits improved mechanical properties and a reduced proportion of free formaldehyde. For the preparation of ureaphosphate, urea and H 2 PO 4 may be used in different molar amounts, preferably in a ratio of 1.5 to 0.65, and heating of the reaction mixture at temperatures of 60 to 110 ° C.

Further reduction of flammability and reduction of formaldehyde content is achieved by the use of ammonium salts alone or with the addition of expanded perlite or a lightened organic filler, the ammonium salts being protected from dissolution in water by preparation of polymeric components. Prepared ammonium salts, for example: (NH 4 NH 4 HCO 3, (NH 4 J 4 PC 4), ammonium citrate, release ammonia in the processing process and also in the finished product, which reacts with formaldehyde to form hexamethylenetetramine, thereby improving occupational hygiene. Ammonium salts with higher thermal decomposition can be used for the thermal curing of the system Direct dosing of pulverulent ammonium salts prevents foaming of the system, therefore, ammonium salts prepared with polymer solutions such as polystyrene, polyvinyl acetate, polymethyl methacrylate, urea-formaldehyde resin and urea-formaldehyde resin are preferred. Various mixtures of ammonium carbonates, ammonium phosphates, ammonium sulphates, ammonium salts, aliphatic, aromatic mono- and multifunctional carboxylic acids can be used, which simultaneously act as flame retardants. Lots of urea-formaldehyde condensation products in combination with ureafosfátmi, inorganic and organic acids are preferably used derivatives of surfactants from the series alkyl, alkaryl acids or alkali salts thereof alone or reaction products of ethanolamine with carbon numbers C-C q _0, or reaction products of aliphatic alcohols with a carbon number C ₁₈ -C _{g of} sulfuric acid, or mixtures thereof. For foaming, treated aqueous dispersions of vinyl polymers, epoxides, rubber latexes, phenol-formaldehyde condensates, and 3 other organic substances such as resorein, dicyandiamide, glycerin, pentaerythritol, starch, urea or melamine, or their sulfonated formaldehyde, and other lignosulfonic acids can be added to the system. , other flame retardants may also be present.

Other inorganic fillers such as porous silicates and pumice stone, ground limestone or dolomite, hydrated alumina may be used as inorganic fillers according to the invention in addition to expanded volcanic glass-based perlite.

198 427 th, borax, contains ground nitrogen-enriched ground superphosphate, basalt or ethylene fibers, asbestos and the like. Basic components, such as limestone or dolomite, which can also be prepared by polymeric components, partially reduce the acidity of the insulating material, improving fibrous materials! mechanical properties of 1 'lightweight material. From the group of organic fillers, in addition to the pulp of lightweight polystyrene or foamed polyurethane, wood sawdust, cellulose, waste fibrous natural or synthetic materials and the like can be used.

Curing according to the type of urea-formaldehyde condensation product used and the type of catalytic system used can be carried out initially in the mold at a normal temperature of 15 to 25 ° C, after fixing the shape stability of the partially crosslinked foaming system. to 120 ° C. According to the degree of lightness and the type of fillers used, the cured 1 'lightweight material exhibits good performance, insulation and mechanical properties, and can be machined by mechanical means, such as e.g. cutting, drilling, etc. The chemical resistance to diluted acids and alkalis is analogous to the non-additive urea-formaldehyde materials. The lightweight insulating material, cured by a catalytic eystem containing organic mono- and multifunctional carboxylic acids and ureaphosphates, exhibits bactericidal activity. This material exhibits good vibration resistance and has a lower linear shrinkage coefficient as compared to non-organic and inorganic fillers of urea-formaldehyde foams.

I illustrate the invention! the following examples, but do not limit its scope. The dosage of the individual components is given in parts by weight (w / w).

Example 1

In 50 wt.% Water, 1.5 wt. sodium dodecylbenzenesulfonate (Dubaral product), 0.2 wt. 1 ^^ 4 ^β wt. ureaphosphate (urea to H 2 PO 4 equimolar ratio used for ureaphosphate preparation, reaction time 1 h. at 90 ° C) and solution aa foamed with air by vigorous stirring with a boom stirrer to approximately ten times the volume. To the foamed system, 110 wt. urea-formaldehyde condensation product (dry matter 65%, free formaldehyde content 0.6%, Ford viscosity 4/20 ° C 2.5 min.), wt. aulfonated urea, 42 wt. expanded perlite (specific weight 155 kg / m @ 2), 11 wt. Crushed polystyrene (specific weight 16 kg / nrb, 2 wt.% hydrated alumina, 1 wt.% CaCl 3 and 7.5 wt.% granular ammonium salts (2.5 wt.% (NH 4 CO 2)). both NH ₃ 28%, 2.5 wt% NH 4 HCO 3 - both NH-j 21%, 2.5 wt% (NH ₄ ) ₂ HPO ₄ ) impregnated with polyvinyl acetate (twice 25% preparation) After homogenization, the material is put into a mold and cured with simultaneous drying at 50 to 55 ° C. The obtained insulating material has a specific weight of 132 kg / aP and its flammability according to ČSN 73 0853 is in group ”B”.

Example 2

In 65 wt. of water is dissolved 0.7 wt. Poron (based on ethanolamine and sodium dodecylbenzenesulfonate), 5.5 wt. citric acid, 0.6 wt. ureaphosphate (prepared from urea at a molar ratio of 1.2, reaction time 2 h. at 105 ° C) and the solution 8a is foamed to eight times the volume. To the foamed system, 125 wt.

198 427 urea-formaldehyde condensation product (65% solids), 10 wt. granulated salts (5 wt.% (NH 4) 3 PO 2 .3H ₂ O - contained NH 4 23%, 2.5 wt.% ammonium citrate - obs.

NH 3 17% and 2.5 wt. NH 4 Gl) prepared with urea-formaldehyde resin, 27 wt. expanded perlite (specific weight 110 kg / m ³ ), 7 wt. of basalt fibers, 2.5 wt. hydrated alumina, 1 wt. borax and 8 wt. crushed, expanded polystyrene (containing flame retardant, specific gravity, 24 kg / m ³ ). The homogenized mixture is molded and cured for 32 hours. with drying at 75 to 80 ° C. The obtained insulating material has a specific weight of 168 kg / m ³ and its flammability according to ČSN 73 0853 is in group B

Example 3

In 50 wt. of water dissolved 4.8 wt. surfactant based on aliphatic alcohols Οθ - C 6 á sulfuric acid (Laurylan N 20, dry matter 35%), 4.3 wt. ureaphosphate (prepared from equimolar mixtures of urea and H 2 PO 4 as in Example 1), 1 wt. acid. form, 10 wt. glycerine, 2 wt. the urea and the solution are foamed to six times the volume. To the foamed βa system was added 105 wt. urea-formaldehyde low molecular weight condensate (water content 26%), 38 wt. expanded perlite (specific weight 150 kg / m ³ ), 2 wt. hydrated alumina, 5 wt. basalt fibers, 8 wt. Crushed polystyrene foam (specific gravity 16 kg / m) and 9.5 wt. granulated ammonium salts (2 wt.% (NH 4) 3 PO 2 .3H ₂ O - containing NH 4 23%, 4.5 wt.% (NH 4 g.HPO 4, 3 wt. NH4 ( ₂ SO4) prepared by polystyrene (in the form of a 25% benzene solution and dried) The homogenized mixture is molded and cured for 10 hours at 60 ° C and 12 hours at 90 ° C. specific gravity 218 kg / m ³ and its flammability according to ČSN 73 0853 is in group B.

Example 4

In 75 wt. water was dissolved by 1.2 wt. mixtures of modified polyglycols (0.6 wt.% Slovamine, 0.6 wt.% Slovasol), 0.4 wt. Poron surfactant (see Example 2)

9.5 wt. acid. of citric acid, 5 wt. waste products from pentaerythritol production and the system is foamed to eight times the volume. 170 wt. urea-formaldehyde condensation product (dry matter 64%), 48 wt. Expansion -5 of imported perlite (specific gravity 110 kg / nr), 13 wt. Crushed polystyrene foam, wt. wood amber sawdust and 15 wt. granulated salts (5 wt.% ground limestone, 5 wt.% (NH 4) 4 PO 4 .3H ₂ O - contained NH 3 23%, 5 wt.% (NH 4 .g. HFO) prepared by polybutadiene- ( in the form of a 20% polymer solution in benzene and drying) The homogenized mixture is put into the mold and cured as in Example 3. The material obtained has a specific gravity of 175 kg / m ³ and its flammability according to CSN 73 0853 is in group B.

Example 5

In 65 wt. of water is dissolved 0.7 wt. a Poron surfactant (see Example 2),

4.2 wt. ureafoephate (prepared from a mixture of urea and H 2 PO 4 ^{in a} molar ratio of 0.8 / 1.2 at 90 ° C, reaction time 1 h), 10 wt. glycerine, 2 h. of dicyandiamide and the solution is foamed to eight times the volume. To the foamed system, 110 wt. mcčovi6

198 427 noformaldehyde prepolymer (water content 26%) 10 wt. of melamine-formaldehyde low molecular product, 42 wt. expanded perlite (specific weight 110 kg / m < 2 &gt;), 11 wt.% crushed polystyrene foam, 1 wt. ground dolomite in a mixture of 8 4 wt. of powdered auperphosphate (prepared with urea-formaldehyde nutrient) and 8 wt. granulated ammonium salts <3 wt. kNH4) ^ PO ^. 3 H 2 O - obs. NH 4 23%, 5 wt. (NH 4 HPO 4) prepared with polymethyl methacrylate (as a 25% solution of polymer in acetone and drying). The homogenized mixture is placed in a mold and cured as in Example 3. The material obtained has a specific gravity of 188 kg / m @ 2 and its flammability according to ČSN 73 0853 is in group B.

Example 6

In 45 wt. water is dissolved 1.6 wt. a Poron surfactant (see Example 2),

1.7 wt. ammonium chloride, 3.9 wt. ureaphosphate, then 2 wt. resorcinol, 4 wt. glycerine, 5 wt. sulfonated melamine, 2 wt. pentaerythritol and 4 wt. The urea solution is foamed to eight times the volume. To the foamed system, 100 wt. urea-formaldehyde condensation product (water content 26%), 5 wt. phenol-formaldehyde resin (water content 25%), 40 wt. expanded perlite (specific weight 150 kg / m @ 2), 5 wt. polyurethane foam grits, 5 wt. shredded polystyrene and 15 homot.d. salts (5 wt.% (NH 4) 2 PO 4 .3H ₂ O - NH 3 content 23%, 5 wt.% (NH 4) ₂ ^SO 4 → 5 wt.% NH 4 Cl), prepared urea-formaldehyde nutrient, with the addition of 2 vol. parts of expanded perlite and 5 vol. parts of polystyrene foam. The homogenized mixture g is introduced into the mold and cured for 32 hours. with drying at 75 to 80 ° C. The insulating material obtained has a specific gravity. 185 kg / m ^ and its flammability according to ČSN 73 0853 is in group B.

Example 7

Dissolve 0.9 wt. a Poron surfactant (see Example 2), 11 wt. d. ureaphosphate (prepared from an equimolar mixture of urea and phosphoric acid), 5 wt. pentearytritol, 12 vol. d. of an aqueous solution of sulfonated urea (dry 50%) and the system is foamed to eight times the volume. To the foamed system, 280 vol. d. urea-formaldehyde condensate, 30 wt. expanded perlite (specific gravity 110 kg / m @ 2), 9 wt. Crushed polyurethane pulp 25 kg / m 2, 15 wt. d. prepared ammonium salts (composition and preparation as in Example 6), 3 wt. hydrated alumina, 1 wt. borax and 1 wt. CaCl. The homogenized mixture aa cures in the form as in example 6. The obtained insulating material has a specific weight of 158 kg / m and its flammability according to ČSN 73 0853 is in group ^H B.

Claims (5)

1. A process for the manufacture of bottled, diuritized urea-formaldehyde materials with reduced flammability, characterized in that a solution containing 30 to 80 wt. water 0.2 to 12 wt. organic or inorganic acids or their aols or a) or ureaphosphates based on urea and phosphoric acid in a molar ratio of 1.5 to 0.65, 198 427 0.1 to 6 wt. of the surfactant, the solution is foamed to eight to ten times the volume, 45 to 180 wt. of an aqueous solution of urea-formaldehyde condensation product having a dry weight of 55 to 70 wt.%, 5 to 15 wt. granulated ammonium salts, impregnated with polymeric substances, a further 15 to 50 wt. of expanded perlite and 6 to 18 wt. Crushed polystyrene or polyurethane and from 5 to 15 wt. inorganic and organic additives, and after homogenization, the material is cured with drying between 40 ° C and 120 ° C. 2. The process according to claim 1, wherein the surfactant is an alkali metal salt of an alkyl or aralkyl sulfonic acid or a reaction product thereof with an ethanolamine having a carbon number of Οθ, or a reaction product of an aliphatic alcohol having a carbon number. ^C 8 ^C 16 ⁸ with sulfuric acid or a mixture thereof. 3. A process according to claim 1, wherein the ammonium salts are salts of carbonic acid, phosphoric acid, sulfuric acid or citric acid impregnated with the polymeric substances themselves or mixtures thereof, wherein their dosing into the feed system is carried out simultaneously with the organic system. or inorganic fillers. 4. A process according to claim 3, wherein the polymers are polystyrene polymethyl methacrylate, polybutadiene, polyvinyl acetate, urea-formaldehyde condensation products. 5. The method of claim 1, wherein basalt or glass fibers, ground limestone or dolomite, phosphorus salts in the form of superphosphate, borax, calcium chloride, hydrated aluminum oxide, sawdust, synthetic fiber materials are used as inorganic or organic additives. , pentaerythritol, urea and melamine or their sulphonated products.