NO172058B - FILLING SUBSTANCES INTUMESCENSE AND USE THEREOF - Google Patents

Abstract

1. Filler-containing, solid or porous intumescent compositions and construction elements which eliminate water at temperatures above 100 degrees C and can be obtained by reacting polysisocyanates with phosphorus-containing hydroxyl compounds, in particular phosphorus-containing condensation products containing at least two hydroxyl groups and obtainable by condensation of primary of secondary alphatic, araliphatic or heterocyclic monoamines and/or polyamines, carbonyl compounds and dialkyl phosphites which optionally contain OH groups, if appropriate with subsequent oxalkylation, and, if appropriate, cyanuric acid and/or cyanuric acid derivatives, in the presence of fillers which eliminate water above 100 degrees C and, if appropriate, further auxiliaries and additives, characterized in that the water-eliminating fillers used are those having means grain sizes above 5 mu m, preferably 8 - 50 mu m, and/or BET surface areas of less than 5 m**2/g, preferably 2 - 0.1 m**2/g.

Description

The present invention relates to filler-containing intumescent masses and their use.

It is known, e.g. from DE-OS 3 302 416, to produce intumescent materials for preventive fire protection by reacting isocyanates with phosphorus-containing, hydroxyl group-bearing condensation products, optionally in the presence of cyamiric acid derivatives and, if necessary, with filler.

A particularly suitable filler for fire protection purposes,

due to the splitting off of water that takes place between 150 and 400°C, it is the aluminum oxide hydrate, or aluminum oxide, which also finds use in preparations made up of other polymer materials.

Aluminum hydroxides are also used in rubber compounds as a flame retardant filler.

Surprisingly, it has now been found that intumescent materials, such as

can be produced by turnover of

polyisocyanates with phosphorus-containing hydroxyl compounds, especially phosphorus-containing condensation products containing at least two hydroxyl groups, which can be produced by condensation

tion of optionally OH group-containing primary or secondary aliphatic, cycloaliphatic, aromatic, araliphatic or heterocyclic mono- and/or polyamines, carbonyl compound and dialkyl phosphites, optionally subsequent oxalkylation, and optionally cyanuric acid and/or cyamiric acid derivatives,

in the presence of auxiliaries and additives when using aluminum hydroxide filler as additive, only preserves its intumescent properties when the filler has an average grain size above 8 pm (D50) and exhibits a BET surface area of less than 2 m<2>/g. The BET method for measuring internal surfaces (according to Brunauer, Emmet and Teller) is known and is based on the adsorption of inert gases on these surfaces.

This observation also applies to all other fillers,

but especially for the Al hydroxides.

This means that with the above-mentioned method only usable massive or porous, Al-hydroxide-filled intumescence materials for preventive fire protection are obtained when, in and of itself, for the field of fire protection, the known filler aluminum hydroxide is used in the above-mentioned grain size range.

The use of filler in such intumescence materials is always desired when the intumescence foams formed by flame contact must have good stability against flame erosion and be able to form ceramic materials. A particularly good tendency to form ceramic materials is always observed when glass, alkali and alkaline earth silicates are used alongside Al hydroxides as filler, e.g. by Na,

K, Ca, Zn or borates and phosphates, respectively polyphosphates

like for example. ammonium polyphosphate, melamine phosphate or -pyrophos-

f that, borax or zinc borate, respectively oxides such as MgO, AI2O3; Fe 2 O 3 , especially CaCO 3 , dolomite, in amounts of 1-100 wt-#, preferably 5-5056, calculated on the basis of the Al hydroxide. Naturally, instead of the Al hydroxide, other fillers can also be used, especially fillers that give off water on contact with a flame, as for example indicated in the following list:

B(OH)3

CaO'Al2O3'10 H20

Nesquehonite

MgC03-3 H20 Vårmlandite

Ca2Mg14(Al, Fe)4C03(C03(0H)42-29 H20

Thaumasitis

Ca 3 Si(OH) 6 (SO 4 ) (C 0 3 ) 12 - H 2 O

Artinite

M<g>2(0H)2C03,3 H0#Etringated

3 CaO'Al2O3-3 CaS04<*>32 H20

Hydromagnesite

Mg5(OH)2(CO3)4-4 H2O

Hydrocalumite

Ca 4 Al 2 (0H) 14'6 E20

Hydrotalcite

Mg 6 Al 2 (0H) 16 CO 3 -4 H 2 O

Aluminohydrocalcite

CaAl 2 (OH) 4 (CO 3 ) 2.3 H 2 O

Scarbroitt

A114(C03)(OH)36

Hydro grenade

3 CaO*Al2O3-6 H2O

Dawsonite

NaAl(OH)CO 3

Gypsum, CaS04*2 H20

hydrous zeolites, vermiculite, perlite, mica, alkali silicates, boric acid, borax, modified graphites, silicic acids.

Due to the good availability and the good resistance, however, aluminum hydroxide is most often preferred.

For all these fillers, the above observation regarding the dependence of the intumescent ability on the grain size applies.

This means that the intumescent ability of the intumescent materials can be surprisingly controlled by the grain size in the filler or the filler mixture contained in the material.

The object of the present invention is consequently massive or porous intumescence masses and construction elements, which contain fillers which split off water at temperatures above 100°C, which can be produced by reacting polyisocyanates with phosphorus-containing hydroxyl compounds, especially phosphorus-containing condensation products that exhibit at least two hydroxyl groups, which can be produced by condensation of optionally OH-group-containing, primary or secondary, aliphatic, araliphatic or heterocyclic mono- and/or polyamlns, carbonyl compounds and dialkyl phosphites, optionally during subsequent oxalkylation, and optionally cyanuric acid and/cyanuric acid derivatives, in the presence of fillers above 100"C splits off water and possibly further auxiliaries and additives, - which is characterized by the fact that aluminum hydroxide with an average grain size of 8-50 pm and a BET surface area of 2-0.1 m<2>/h is used as a filler that emits water .

The intumescent masses according to the invention contain between 0.3 and 85 wt-5, preferably 30 to 60 wt-# of Al hydroxide of the aforementioned grain size.

According to the invention, it is further preferred that the intumescence masses next to Al hydroxide of the aforementioned grain size contain additional filler on a carbonate basis with a total content of filler of 0.3-85% by weight.

The invention further relates to the use of the mentioned intumescence compounds for the production of structural elements for preventive fire protection.

As you know, intumescent materials are materials that, when exposed to fire and heat, foam up and thereby form an insulating and fire-resistant foam, which protects the areas behind from the impact of the flames. Such intumescence masses are known (DE-OS 30 41 731, DE-OS 31 09 352).

Structural elements with an intumescent effect for preventive fire protection are understood to mean structural elements whose fire protection effect consists in the fact that in the event of a fire they expand when heated to form a fire-resistant and insulating foam, thereby closing the faults, cracks and joints, cracks, etc. that often occur in the event of a fire, against the passage of smoke and flames, respectively flame gases, and the rear parts of the room facing away from the fire are shielded against fire attacks.

As such construction elements can be mentioned, for example: Wall coverings, covers for containers, plates, covering elements, safety housings, profiles that are built-in or inserted or pressed into joints, sealing elements, semi-finished products and molded parts for special geometrically different versions of safety devices, "sandwiches", respectively individual components of composite materials in plate form, plugs, closing elements, cable routes.

Preferably, these are construction elements of more or less hard, self-supporting or reinforced intumescent materials, which can be massive, porous or foam-like in nature.

The hard intumescence materials that have been suitable for the production of such structural elements up to now have the disadvantage that they have unsatisfactory resistance to flame erosion.

The conventional intumescence materials involve mixtures of several components, e.g. about a mainly phosphorus-containing acid donor, about a foam-forming, respectively improving "Carbonific", mostly a polyalcohol and a propellant, mostly an ammonium salt or also other nitrogen-containing compounds.

Mixtures of these components, possibly with further auxiliaries, have so far been used as intumescent masses as granulated powder mixtures or mixed with binders. Alkali silicates with water components that evaporate on contact with flame are also used for this purpose, i.e. as intumescence compounds for preventive fire protection.

With the exception of certain nitroaromatics, which can only be produced under extensive precautions, which also act as intumescent agents, the known intumescent masses are in practice partially hygroscopic, partially air-sensitive and water-sensitive when operating satisfactorily. Consequently, even when they are processed with relatively water-resistant binders, they are not water-resistant and can only be used in cases where no rain or liquid water can occur, often a protection against air and humidity access must also be provided.

On the other hand, there is a significant need for water-resistant intumescence compounds in shipbuilding, the car industry, high-rise buildings, underground construction and in the area of electrical engineering.

Against the background of this need, DE-OS 33 02 416 specifies construction elements that are made of water-resistant intumescent materials.

Since these intumescence materials are not satisfactory in terms of resistance to the significant flame erosion of the intumescence foam occurring during strong fires, it has been necessary to search for improved solutions made possible by the present invention.

The filler-containing intumescent masses according to the present invention can be produced in such a way that in the event of a fire, a stabilized, insulating and flame-resistant intumescent foam is formed with the help of the ceramizing fillers, respectively the filler mixtures, which protect against mechanical and oxidative destruction of the intumescent foam by the flame (flame erosion) . For this purpose, however, according to the invention, it is required that the fillers, which preferably emit water above 100°C, are used in a suitable grain size range, surprisingly, falling below the above-mentioned grain size range prevents the formation of the intumescent foam.

As polyisocyanates for the production of intumescence compounds according to the invention, such compounds are mentioned as e.g. is described in DE-OS 3 302 416 on pages 12-15.

According to the invention, intumescent masses and structural elements of such polyisocyanates which can be obtained by aniline-formaldehyde condensation and subsequent phosgenation are preferred, as well as such intumescent masses and structural elements in which condensation products exhibiting at least two hydroxyl groups of the formula are used as phosphorus-containing hydroxyl compounds

in which

E = C 1 -C 8 -alkyl or C 1 -C 8 -hydroxyalkyl and

X = H or methyl.

According to the invention, however, other phosphorus-containing hydroxyl compounds also come into consideration, such as e.g. preferably at least two hydroxyl groups containing esters of phosphorus-containing acids, such as phosphoric acids of varying degrees of condensation up to metaphosphoric acid, or of phosphonic acids, phosphinic acids, e.g. their alkylation products, respectively turnover products,

salts of hydroxyl group-containing amines and the various phosphoric acids, respectively

amides of the various phosphoric acids, which contain hydroxyl groups,

respectively mixed forms thereof.

As cyanuric acid derivatives, melamine and/or water-insoluble melamine or urea-formaldehyde condensates are preferred, in principle a wide range of cyanuric acid derivatives are suitable.

The intumescent materials used usually have specific gravity from 0.05 to 1.6, preferably from 0.15 to 0.9 g/cm 5 .

The filler-containing intumescent masses according to the invention which, in addition to less than 1$, preferably less than 0.5$ of water, may optionally also contain cyamiric acid derivatives and further additives such as plasticizers, e.g. phosphoric acid ester or methylphosphonic acid ester, whereby the addition of melamine and/or methyl phosphoric acid dialkyl esters is preferably carried out, while the addition of the further additives, e.g. of polyalcohols, dyes, pore stabilizers, propellants, fillers, etc. have a complementary character when it comes to the object of the invention, form massive to foam-active products with adjustable intumescence properties and good water resistance and good resistance to flame erosion, which is to be considered a significant technical advantage.

In the following, the production of the intumescence materials according to the invention containing water-releasing filler, respectively the construction elements that can be produced as a result, will be described in more detail.

In the simplest case, they are produced by mixing and reacting polyisocyanates with the above-mentioned filler-containing condensation products, possibly using catalysts based on e.g. amines, phosphorus compounds or organometallic compounds, which are known to the person skilled in the art, in open or closed forms, which may optionally contain inserted reinforcement elements, or the reaction products are brought to the desired form after production by means of sponge-cutting processing. A representation, e.g. as a coating or filler material, in place to achieve the desired shape in situ can also be considered, as well as spraying the reaction mixture, with or without the addition of auxiliary gas or heat, on different carriers.

Machines known from polyurethane technology can be used.

The mixing ratio between polyisocyanates (preferably polyisocyanates which can technically be produced on the basis of aniline-formaldehyde condensates and subsequent phosgenation) and the isocyanate-reactive reaction partner is suitably selected approximately stoichiometrically; under this, account must be taken of any proportions of water present in the reaction mixture. If a less good water resistance of the intumescent material can be tolerated, it is also possible to work with less than the stoichiometric amount of isocyanate, the amount should not, however, fall below 50 mol-56 of the stoichiometrically required amount of isocyanate. To achieve special effects, e.g. to achieve a desired additional reactivity for the intumescent material, the possibility of higher cross-linking and improved combinability with additional components in the construction element, or also to enable later curing reactions of the intumescent material, the stoichiometrically required amount of isocyanate can also be exceeded, whereby generally 5 0 mol-56 in addition to the stoichiometric amount of isocyanate must not be exceeded, although higher amounts of isocyanate can be considered in special cases.

In the production of the intumescence compounds, work is carried out analogously to the procedure in DE-OS 3 302 416.

The construction elements obtained by the invention can consist exclusively of the above-mentioned intumescent materials, but preferably they can also constitute material combinations and/or contain other assembly or coating aids and additives to promote workability for special areas of application, respectively the applicability, e.g. e.g. contain reinforcement elements and/or carrier substrates.

In the production of such structural elements, work can be done continuously or discontinuously.

The production can take place by mixing the components, respectively with already pre-mixed component mixtures, on site, whereby the reaction mixture is mechanically or manually poured into closed openings, respectively heated or unheated forms, without pressure or under pressure, after which the masses can then foam up, respectively harden. Using suitable technical devices, the mixture can be sprayed, applied or poured onto the substrate or substrate to be protected. It must also be taken into account that one can first produce semi-finished products, e.g. foam materials, profiles or coatings and then process these to the extent technically required, e.g. by cutting, pressing, punching or hot deformation at 100 to 250°C, welding, coating and bonding.

By combining the filler-containing intumescent materials according to the invention with foamed or solid, inorganic or organic additives, such as e.g. polystyrene foam, polyurethane foam, phenoplast types, aminoplast types or kis or bladder clay, urea or phenolic resin foam, foam glass, glass fibres, wood, mineral wool, pumice etc., composite materials with special intumescence properties can also be obtained as construction elements. The manufacture of structural elements reinforced with fibers or threads, respectively woven materials, strings or tiles of organic or inorganic materials, or their use as components in multi-layer or "sandwich" constructions shall also be taken into account; likewise the combination with other intumescence materials on an organic or inorganic basis.

The construction elements obtained by the invention are distinguished by the fact that they do not lose their intumescent properties even when exposed to liquid water. In general, they start to foam at temperatures above 200°C, especially above 300°C. In the flame, they expand by 50 to over 300 volume-56, depending on composition, grain size selection in the filler, and the heating method. They can preferably be composed halogen-free and can often be set so that they are highly flammable. When exposed to flame, intumescence foam is produced, which has good resistance to flame erosion.

The construction elements obtained by the invention find particular application in cases where precautions must be taken for preventive fire protection during coating, formwork, separation, lining, filling or sealing of cavities, respectively building parts within the area of high-rise construction, underground construction, electrical engineering, in automotive, the machine and construction industry and in cases where the occurrence of condensation water, mixing water for mortar or cement, condensation water, rainwater or groundwater must be expected.

In what follows, the invention will be described in more detail with the help of examples: The specified parts are parts by weight, or percentage by weight, unless otherwise stated.

Polyisocyanate A: Technical 4,4'-diphenylmethane diisocyanate with a content of isomers and approx. 109a higher functional multi-core shares. Isocyanate content approx. 31$.

Polyisocyanate B: Similar isocyanate with an approx. twice as much

high content of highly condensed components, isocyanate content approx. 31$.

Polyisocyanate C: Similar isocyanate with a once again doubled content of higher condensed proportions. Isocyanate content approx. 31$.

For example, technical products with the following idealized structures are used as phosphorus-containing condensation products for reaction with the isocyanates:

Condensation product K:

(CH 5 O) 2 P 0 CH 2 N(C 2 H 4 OH) 2 ; water content approx. 0.25%

Condensation product L:

(CH 3 ) O 2 PbCH 2 N(C 3 H 6 OH) 2 ; water content approx. 0.3%.

For example, the following filler is used: Aluminum hydroxide filler with the grain sizes and other properties specified in the following table.

("Apyral B" types from Bayer AG)

CaCQ3 filler F 215 and F 240: gypsum filler F 315 and F 340

Additional additives

Z]_: Plasticizer methyl phosphonic acid diethyl ester

Z2: Addition product of 1 mol of ethylenediamine and 3.7 mol

propylene oxide

Z3: Iron oxide red pigment ("Bayferrox 140 M" from Bayer AG) Z4: Polyether silicone stabilizer ("OS 20", Bayer AG)

Z5: Anhydrous zeolite (powder, "Baylith-T", Bayer AG)

The production took place by mixing the condensation product, optionally mixed with filler and other additives, with the isocyanate at 15°C with good stirring, completely in a sealable container. vertical plate form with a thickness of 3 cm, which had previously been heated to 40°C, and there brought to reaction. After 10 minutes, the mold was removed.

The composition of the manufactured intumescent materials is shown in the following table:

Squares with an edge length of 1 cm were cut from the produced intumescent plates, and these were placed in an oven with air circulation which had been previously heated to 450°C. After 30 minutes, the test pieces were removed from the oven and the increase in volume was determined. The intumescence properties were rated as follows:

The assessment of the intumescence plates 1-13 can be found in the table. Similarly, the assessment of the intumescence for similar squares with an edge length of 0.5 cm, similar to a wire mesh, which was heated from above for 3 minutes with the non-luminous flame of a natural gas Bunsen burner.

In all cases, the flame on the test specimens went out immediately when the burner flame was removed. It left a non-glow intumescence foam.

Example 14

To prepare a flowable formulation, mix:

25 parts condensation product K; 20 parts F 8; 10 parts F 240; 0.5 parts Z3, 10 parts Z]^; 0.03 parts Z4, and this mixture is mixed with 30 parts isocyanate C using a transport and mixing unit with an agitator mixing head commonly known from polyurethane chemistry.

The finished reaction mixture is filled into a larger container (2 litres), where it hardens into a porous intumescence material which has a volume weight of approx. 170 kg/m5.

Furthermore, this is introduced into a closable plate form as described above, until this is 8056 filled; after closing the mold, the reaction mixture hardens into a plate with a volume weight of approx. 550 kg/m3.

Furthermore, it is introduced into an open plate form in which there is a pierced 0.8 mm thick stainless steel plate in the middle between the side walls, so that this is surrounded by the hardening and swelling reaction mixture. The plate of the intumescence mass that results, which in the middle part is reinforced with perforated steel sheet, has the dimensions 1.5 x 12 x 120 cm.

The intumescence for the material produced in free and closed form is assessed when exposed to flame as 3. Afterburning is not observed. In the burner flame, the intumescence foam formed has persistence even after 90 minutes. Ceramisation is observed, i.e. formation of an inorganic foam lattice material with good intrinsic strength.

Example 15

The following mixtures are produced:

Mixture 1:

250 parts condensation product K; 200 parts F 25; 5 parts Z3; 90 parts Z1;

0.4 parts Z4;

3 parts Z5.

Mixture 2:

300 parts isocyanate C;

100 parts F 240;

100 parts ammonium polyphosphate;

1 part Z3.

The two mixtures are mechanically stirred together at 19"C and, after 20 seconds of stirring time, are filled into a plate mold as described in examples 1-14. A casting time of 7 minutes is observed, after which the plate of the intumescent material can be removed from the mold, which had been treated with a wax-based release agent. The plate has a volume weight of approx. 450 kg/m<3>. The plate is flexible. In the intumescence test, there is an intumescence of 3-4 when exposed to flame. The material does not after-burn. When exposed to flame for several hours with it does not shining the flame of a bunsen burner does not break down the formed, stable intumescence foam, but, after general oxidation of the carbonization grid, a firm, white, porous ceramization cake is left behind, which protects the areas behind it from further flame attack. No flame erosion takes place.

Claims (4)

1. Massive or porous intumescent masses and construction elements, which contain fillers which release water at temperatures above 100°C, which can be produced by reacting - polyisocyanates with phosphorus-containing hydroxyl compounds, especially phosphorus-containing condensation products that exhibit at least two hydroxyl groups, which can be produced by condensation of optionally OH-group-containing, primary or secondary, aliphatic, araliphatic or heterocyclic mono- and/or polyamines, carbonyl compounds and dialkyl phosphites, optionally during subsequent oxalkylation, and optionally - cyanuric acid and/or cyamiric acid derivatives, in the presence of a filler that emits water above 100'C and possibly further auxiliaries and additives, characterized in that aluminum hydroxide is used as a filler that emits water with an average grain size of 8-50 pm and a BET surface area of 2-0.1 m<2>/g. 2. Intumescent masses according to claim 1, characterized in that they contain as filler Al-hydroxide of the aforementioned grain sizes in amounts of 0.3 to 85% by weight. 3. Intumescent masses according to claims 1 and 2, characterized in that, in addition to Al hydroxide of the aforementioned grain sizes, they contain additional carbonate-based filler at a total amount of filler of 0.3 to 85 weight-5é. 4. Use of intumescence compounds according to claims 1-3 for the production of structural elements for preventive fire protection.