NL8202362A - RIGID, WATER RESISTANT CERAMIC PHOSPHATE MATERIALS AND METHOD FOR PREPARING IT. - Google Patents

Description

- 1 - Λ _ .- '2 N / 30.892-Kp / Pf / cs

Rigid, water-resistant ceramic phosphate materials and process for their preparation.

The present invention relates to rigid, water-resistant ceramic phosphate materials, and more particularly to rigid, water-resistant ceramic phosphate materials, which do not require subsequent thermal curing.

5 Refractory metal phosphates have long been recognized as useful construction and insulation materials. Are compositions already known containing phosphoric acid, metal oxide and metal silicates? however, compositions containing these ingredients and having sufficient strength are extremely difficult to prepare. For example, mixtures of alumina and 85% phosphoric acid are viscous and difficult to handle. When such mixtures are diluted with water, they become considerably easier to handle; nevertheless, when silicate, for example, calcium silicate, is added and the resulting phosphate is thermally cured to expel the excess water, the resulting refractory nevertheless has a relatively poor tensile strength. On the other hand, when all components are mixed together at once without the use of additional water, a rapid reaction ensues, which cannot be controlled under normal factory conditions.

Various phosphate compositions and methods for their preparation have already been described. For example, U.S. Pat. , stirring the mixture with phosphoric acid and allowing the resulting foam to solidify. US Pat. No. 3,148,996 discloses compositions which cure without heating to a rigid mass and which can be made porous by incorporating gas bubbles. These compositions consist of water, an acid phosphate consisting of phosphorus pentoxide and calcium, aluminum or zirconium oxides, and finely divided calcium silicate. These compositions are formed by making a viscous solution of 8202362 t - 2 - water, phosphorus pentoxide and a suitable metal oxide, adding calcium silicate to the mixture and allowing this mixture to partially cure. Foaming is then generated by adding an internal foaming agent or by introducing mechanical gas bubbles. U.S. Pat. No. 3,330,675 discloses compositions containing acidic aluminum phosphate, the carbonate, oxide, hydroxide or silicate of magnesium or zirconium, and organic or inorganic gas producing materials. Likewise, other patents disclose similar phosphate foams, wherein a powdered material is incorporated into the acidic mixture, thereby generating foams through the release of hydrogen gas.

While it is clear from the aforementioned literature that considerable effort has been put into the development of useful phosphate foams, many problems remain. Most known foams have poor bond strength, making them unsuitable as building materials. Some are moisture sensitive, and many require heat curing to improve bond strength, and most contain other additives to overcome weakness problems. In addition, most commercially manufactured foams contain blowing agents, which can increase the cost of the product and sometimes contribute to bond weakness.

Accordingly, an object of the present invention is to provide strong moisture resistant ceramic phosphate materials which can be prepared without the use of external heat.

A further object of the present invention is to provide processes for the preparation of rigid phosphate foams without the use of added blowing agents.

Furthermore, another object of the present invention is to provide methods for the simple and continuous preparation of phosphate foams, avoiding collapse of the foam.

These and other advantages of the present invention become apparent from the following description of the invention.

The present invention relates to rigid 40 water-resistant ceramic phosphate materials, which are prepared from components containing metal oxides, calcium silicate and phosphoric acid. By pre-reacting part of the metal oxide with the phosphoric acid and / or adjusting the temperature of the acid solution when it is combined with the other ingredients, the nature of the resulting product can be controlled such that foamed or non-foamed ceramic phosphate materials are obtained.

In an embodiment of the method according to the present invention (1) at least € δη metal oxide is selected from the group of MgO, CaO or ZnO or its hydrates, while the metal oxide is calculated a total of 11-65 parts by weight, on an anhydrous basis / (2) prepare a reaction solution containing a portion of the metal oxide and 80-190 parts by weight of a phosphoric acid solution with the equivalent based on the weight of the acid solution of 35-75% by weight of phosphorus pentoxide, the water of hydration of the metal oxide is included in the calculation of the phosphorus oxide content; and (3) a mixture is prepared containing the remainder of the metal oxide and about 100 parts by weight of calcium silicate. The temperature of this reaction solution is brought to a desired value and the mixture is mixed proportionally with the reaction solution. The resulting mixed material is brought into a desired shape and its components are allowed to interact. The amount of metal oxide used for the preparation of the reaction solution, and the temperature of the reaction solution are chosen to determine approximately the time at which the mixed material becomes rigid relative to the time of evaporation of the water. occurs.

In a second embodiment of the method of the present invention, (1) a mixture is prepared comprising 11-65 parts by weight, calculated on an anhydrous basis, of at least one metal oxide selected from Al2Q3, MgO, CaO or ZnO, or its hydrates, and contains about 100 parts by weight of calcium silicate; and (3) a reaction solution is prepared containing 80-190 parts by weight, calculated on an anhydrous basis, of a phosphoric acid solution having the equivalent by weight of the acid 8202362-4 solution of 35-75 wt. % phosphorus pentoxide, the hydration water of the metal oxide being included in the calculation of the phosphorus pentoxide content. The temperature of the reaction solution is brought to a desired value and the solution is mixed proportionally with the mixture. The resulting mixed material is shaped to a desired shape and its components are allowed to interact. The temperature of the reaction solution is chosen to determine approximately the time at which the mixed material becomes rigid relative to the time at which water evaporation occurs.

In a third embodiment of the present invention, (1) at least the metal oxide is selected from Al2 O3, MgO, CaO or ZnO or its hydrates, while the metal oxide is a total of 11-65 parts by weight, calculated on an anhydrous basis, matters; (2) a reaction solution is prepared containing a portion of the metal oxide and 80-190 parts by weight of a phosphoric acid solution having the equivalent based on the weight of the acid solution of 35-75% by weight of phosphorus pentoxide, wherein the water of hydration of the metal oxide is included in the calculation of the phosphorus pentoxide content; and (3) a mixture is prepared containing the remainder of the metal oxide and 100 parts by weight of calcium silicate. The mixture is mixed proportionally with the reaction solution and the resulting mixed material is brought into a desired shape in which the ingredients are allowed to interact. The amount of metal oxide used for the preparation of the reaction solution is chosen to determine approximately the time at which the mixed material becomes rigid relative to the time at which water evaporation occurs.

The present invention further comprises a composition suitable for obtaining a rigid, water-resistant ceramic phosphate material, which composition consists of (1) 11-65 parts by weight, calculated on an anhydrous basis, of at least έέη metal oxide selected from the group of Al 2 O 2, MgO, CaO or ZnO or its hydrates; (2) 80-190 parts by weight of a phosphoric acid solution containing the equivalent by weight of the acid solution of 35-75% by weight of phosphorus pent-40 oxide, the water of hydration of the metal oxide including 8202362%. - handles in calculating the phosphorus pentoxide content; and (3) 100 parts by weight of calcium silicate.

The present invention further comprises a rigid, water-resistant phosphate material, which is obtained by (1) 5 11-65 parts by weight, calculated on an anhydrous basis, of at least. One metal oxide from the group of AlOg, MgO, CaO or ZnO or its hydrates; (2) 80-190 parts by weight of a phosphoric acid solution which, based on the weight of the acid solution, contains the equivalent of 35-75% by weight of phosphorus pentoxide, the hydration water of the metal oxide being included in the calculation of the phosphorus pentoxide content ; and (3) reacting 100 parts by weight of calcium silicate.

The ingredients to be used in the practice of the present invention are all commercially available. Calcium silicate (100 parts by weight) is preferred according to the teachings of the invention, although other silicates can also lead to satisfactory results. Calcium silicate occurs in nature and is called wollastonite in that form. Suitable foamed or non-foamed products can be obtained when this material is used in powdered form as described below. The particle size is preferably small enough to make foams, so that the majority of the silicate passes through a sieve of 200-mesh Tyler Standard (mesh size 0.074 mm).

A number of metal oxides, such as aluminum oxide, magnesium oxide, calcium oxide and zinc oxide, can be used to obtain a satisfactory ceramic phosphate material. These oxides are used in powder form, with more finely divided oxides having a particle size of 0, 043 mm or smaller (325 mesh Tyler Standard) generally giving superior results. Hydrated forms of the oxide can also be used and are preferred in many cases.

In case a hydrate is used, the hydration water must be taken into account, in order to avoid excess water for the reaction. This can be done in a simple manner by including the hydration water in the calculation of the phosphorus pentoxide content of the phosphoric acid solution.

In the practice of the present invention, about 11-65 parts by weight of metal oxide, calculated on an anhydrous basis, 8202362-6, relative to 100 parts by weight of calcium silicate, may be used; however, it is preferred to use about 13-26 parts by weight of metal oxide, in particular about 15-20 parts by weight. The amount of oxide used will depend on whether it is in the hydrated form and / or on its reactivity.

Anhydrous magnesium oxide reacts much faster with phosphoric acid than anhydrous alumina. For example, the former will respond within a few minutes, while the latter may take several hours depending on the temperature of the acid solution. However, when hydrated forms are used, the deviations in the reaction times are considerably reduced. Hydrated magnesium oxide reacts faster than anhydrous magnesium oxide, and it also reacts much faster than hydrated aluminum oxide.

Nevertheless, hydrated alumina is considerably more reactive than anhydrous alumina because it reacts with the phosphoric acid solution within a few minutes instead of hours. The consequences of the reaction times will be further explained below.

Suitable products can be obtained by using one of the indicated oxides, alone or in combination, but anhydrous magnesium oxide (calcined) and hydrated alumina are particularly preferred in the practice of the present invention. Magnesium oxide tends to increase the strength and moisture resistance of the final product, while alumina tends to provide superior curing properties.

Phosphoric acid is available in a variety of concentrations, with 85% being the most common concentration of ortho-phosphoric acid. Other compositions, such as polyphosphoric acid, which, when diluted with water, provide phosphoric acid, may also be satisfactory for carrying out the present invention, provided that the total water content of the reaction system is not too high. Too much water should be avoided because otherwise products are obtained which, although water resistant, have weak strength. On the other hand, there is also too little. water harmful, not only because mixing of the materials is difficult to accomplish, but because in the case of foamed products only high density foams are obtained.

8202362 - 7 - «'“

As a general rule, the phosphoric acid will be suitable if it contains the equivalent of about 35-75 wt% phosphorus pentoxide based on the weight of the acid solution.

Preferably, the equivalent of phosphorus pentoxide is ca.

40-70% / and more particularly about 45-65%. The remainder of the acid solution consists of water including any hydration water of the metal oxide for the purpose of simplifying the calculation. About 80-190 parts by weight of the acid solution can be used in the practice of the present invention, but preferably these are about 90-150 parts by weight, especially about 100-130 parts by weight of acid.

Although the ingredients used according to the practice of the invention have long been known as such in the prior art, the advantages achieved when these ingredients are combined as according to the invention have never been recognized. It has been found that when the way in which the ingredients are combined is controlled and excess water is avoided, a product is obtained which does not require heat curing and is water resistant. Although no theory regarding the nature of the reactions involved may determine the scope of protection requested, do two separate yet interdependent phenomena appear to occur? these are the evaporation of the water and the bonding of the materials. Heat generated by the reactants causes most of the water to evaporate, allowing the water vapor to serve as a foaming agent. Both binding and curing occur for approximately the same time, leading to the formation of a rigid ceramic-like material. These two phenomena will be referred to below as "evaporation" or the "evaporation step" and "curing" or the "curing step".

For the practice of the present invention, a reaction solution is preferably prepared by adding a desired amount of the metal oxide to the phosphoric acid solution. In addition, liquid additives such as surfactants can also be included in the reaction solution. The remainder of the metal oxide and the entire amount of calcium silicate are then combined and mixed with any solid additives, such as reinforcing fibers, thickeners, dyes and the like. The temperature of the reaction solution is preferably brought to a desired value and the solution is mixed proportionally with the other dry ingredients. The mixed material is placed thereon in a desired shape on which the components of the system can interact. The products obtained do not require heat curing and can be placed in boiling water without any adverse effect. Nevertheless, they are not heat sensitive since samples 10 have been heated to 870 ° C without significant loss of strength.

It has been found that the relative times at which evaporation and curing occur determine the nature of the product obtained. For example, when the evaporation step 15 is reached for the curing step, the water vapor will foam the mixture before the mass becomes rigid. On the other hand, when curing first occurs, the material can no longer foam and the water vapor escapes via the intermediate pores. The consequences of the latter sequence of events will be explained in more detail below, but in both cases a product can be obtained which does not require heat curing on the one hand but is water resistant on the other.

Two factors contributing to the above are the amount of metal oxide used in the pre-reaction with the phosphoric acid and the temperature of the reaction solution when it is combined with the remaining dry ingredients. If only one of these factors is controlled, a ceramic-like material can still be prepared. Still, it is preferable to control both parameters in order to simplify the treatment and obtain a superior product.

From the following it can be seen how these factors can be varied. Generally speaking, when relatively less metal oxide is used in the pre-reaction with the phosphoric acid, relatively more foaming will occur during the subsequent mixing step before the material mass becomes rigid, provided that the temperature of the acid solution is not too low. In contrast, if more metal oxide is used in the pre-reaction with phosphoric acid, 8202362 * - 9 - less foaming will occur before the mass becomes rigid. When sufficient metal oxide is used for the pre-reaction, virtually no foaming will occur. This result is apparently obtained because the pre-addition of the metal oxide tends to extend the duration of the exothermic reaction or reactions which cause the water to evaporate.

The temperature of the reaction solution during the subsequent mixing treatment can also significantly affect the product to be obtained. The higher the temperature of this solution, the more vigorous the development of water vapor and the faster water evaporation occurs when the reaction solution is mixed with the other dry ingredients. For example, when the temperature is too high, the likelihood is greater that foams are obtained which contain voids or which foam quickly and then collapse. This effect can be somewhat mitigated by including a surfactant in the reaction solution.

When the temperature is too low, the exothermic reaction can be suppressed so much that no foaming will occur. Furthermore, too low a temperature can be harmful because the material obtained is a relative one. may have weak bond strength. The optimum temperature of the reaction solution may vary depending on the reagents, but it has generally been found that a temperature range of about 2-27 ° C will lead to satisfactory results. When foams are made, the preferred temperature range is approx.

3-7 ° C, especially 4.5 ° C, unless a foaming agent is added as described below.

In practice, other factors apart from the amount of material to be reacted and the temperature of the acid solution must be taken into account, many of which depend on the nature of the product to be prepared. When foams are made, the goal is to allow the foam to reach a desired height when curing occurs. Essentially, the water evaporation causing the foaming must be controlled over time to yield uniform cell size in a product that has reached the correct height and density upon completion of the curing. The cell size is influenced by the rate of the water vapor release 8202362 - 10 and by the viscosity of the acid solution. The viscosity in turn depends on the type of oxide or oxides used, the particle size of the oxide, and the temperature of the acid solution.

Solutions of different viscosities are obtained when the different oxides are dissolved in phosphoric acid. For example, when increasing amounts of magnesium oxide are added to a metered amount of a standard strength acid solution (e.g., 85%), 10 viscosities ranging from about 0.05-1.00 Pa.s at 22.2 ° C are observed. However, when comparable molar amounts of alumina are added to a second portion of the same acid solution at 22.2 ° C, viscosities from about 0.05 Pa.s to only 0.40 Pa.s are observed. For making superior foams, it is preferred that the viscosity of the acid solution at the time of mixing with the other ingredients does not exceed 0.40 Pa.s. Thus, it appears that a second limitation on the applicability of magnesium oxide, apart from its tendency to violently cause foaming, is the viscosity of the reaction solution obtained when using it.

The higher the viscosity of the reaction solution, the poorer the mixing of the ingredients and the poorer the foam quality of the product obtained. Therefore, it is often desirable to use more than one oxide. For example, one oxide could be used to prepare the reaction solution and another could be combined with the calcium silicate. On the other hand, the oxide can be used in the form of a mixture both to form the reaction solution and to mix with the calcium silicate. Numerous possibilities exist, all of which should be included within the scope of the present invention, and the present invention should not be limited to these two illustrated examples.

The density of the final product will largely depend on the amount of metal oxide used to form the reaction solution, because the more metal oxide used, the greater the density. As a general rule, in the absence of added foaming agents, using about 0-0.3 part by weight of metal oxide per part of P2O5 in 8202362 - '- 11 - * the acid solution to form the reaction solution, foams with densities of 640 kg / m and lower up to 240 kg / * 3 m. However, if more than 0.3 parts of metal oxide is used, a non-foamed ceramic material 5 can be expected. Nevertheless, practical considerations, such as viscosity, affect the upper limit of the material to be reacted? for example, typically no more than 50% of the metal oxide can be easily used in the pre-reaction.

Other considerations affecting the foams are particle size, surface properties and reinforcing materials. A small and uniform particle size is significantly preferred in the practice of the present invention because of the tendency of such material to promote fine cell structure. As already noted, metal oxide with a particle size of less than 0.043 mm and calcium silicate with a particle size of less than 0.074 mm is preferred.

Cell size also depends on the surface properties of the material, and it often helps to incorporate one or more surfactants to promote cell stability. Virtually any surfactant that does not react with the phosphoric acid can be used. A surfactant which has been found to be particularly suitable is dimethyl cocamine oxide which is marketed by Armak under the name Aramox DMC. However, care should be taken when handling this material because it has an irritating effect on skin and eyes.

Because foams have a porous nature, they tend to exhibit less tensile strength than non-foamed materials. Accordingly, it is often recommended to add fibrous stiffeners to strengthen the foam. Polyester, glass, polypropylene,. and nylon have been used, inter alia, successfully, although the conditions under which the final product will be used may affect the choice of fiber. For example, for a high temperature application, glass fibers are considerably more stable than organic fibers. In general, fiber lengths of 3-25 mm will be suitable, with some preference for fibers of about 12 mm.

8202362 - 12 -

In the preparation of non-foamed phosphate ceramics, factors such as particle size, viscosity, temperature and surface properties become much less important because the cell structure is not a factor to be considered.

Accordingly, materials with coarser particle size and higher viscosity of the reaction solution can be used, which are limited only by conditions due to the handling of the reagents. A much higher temperature for the reaction solution can also be used because the non-foamed material will not collapse. Furthermore, there will be no need for surfactant because there is no cell stability problem.

Apart from these considerations, the objective in the preparation of a non-foamed ceramic is to compare that of the preparation of a foamed material, the main difference being that with non-foamed materials it is necessary to remove the evaporation step. adjust until the mass has become rigid, thereby preventing expansion of the phosphate material. This is easily accomplished by using a larger amount of the metal oxide in the pre-reaction. However, care must be taken to ensure that water can escape from the non-foamed material. When the internal pressure of the structure is too. becomes high due to water pressure, the rigid ceramic can crack 25. Therefore, in the preparation of non-foamed phosphate ceramics, it is often preferable to include porous fillers which can provide passages through which the water vapor can escape. Examples of such suitable fillers are vermiculite and perlite.

Surprisingly, it has also been discovered that satisfactory foamed products can be obtained by combining the techniques of the present invention with already known foaming agents. The prior art refers to the use of carbon dioxide or carbon dioxide producing materials and hydrogen or hydrogen producing materials, as well as other organic or inorganic gas producing materials in the preparation of phosphate products. Such agents can also advantageously be used in the preparation of the rigid, water-resistant phosphate ceramics of the present invention.

8202362 <4 - 13 - * *

While virtually any known foaming agent can be used, for example, the results obtained using different carbonates are shown. Carbonates such as MgCOg, CaCO2, ZnCO2, Li2COg and the like, or mixtures thereof, yielding relatively insoluble phosphates are preferred; However, MgCO 2 is particularly preferable because it provides a supreme foam with relatively even cell size and generally suitable density. Other carbonates, such as Na2C (> 2 and KjCO ^ 10) will provide relatively soluble phosphate salts, but can also be used when leaching the phosphate from the resulting phosphate ceramic when exposed to water will not be harmful.

When using dry foaming agents, it is often desirable to mix them with the other dry ingredients including the calcium silicate and a portion of the metal oxide; however, these foaming agents can also be added separately. Since the foaming obtained in the presence of such agents is not caused by water evaporation, it is undesirable for the exothermic reaction to occur prior to curing. Therefore, it is often necessary to use a larger portion of the metal oxide in the pre-reaction with the phosphoric acid solution. This often leads to an undesirable increase in the viscosity of the acid solution. Accordingly, when using an added foaming agent, it may be necessary to slightly dilute the acid solution in order to control the viscosity. However, care must be taken to avoid the use of excess water because the combination of the use of additional water and the pre-reaction of more of the metal oxide tends to lower the temperature of the exothermic reaction, thereby probability of obtaining a phosphate ceramic of unsatisfactory quality increases.

As an additional consideration, the temperature of the reaction solution at the time of mixing with the dry ingredients can often be higher when the foaming is achieved using dry foaming agents instead of using water evaporation, because the curing will occur before the occurrence of the exothermic reaction. For example, when using dry foaming agents, it is often desired that the reaction solution has a temperature in the range of about 10-15 ° C instead of the aforementioned 3-7 ° C in conjunction with the water evaporation caused foaming.

It is of course also possible to use a liquid foaming agent, such as a fluorinated hydrocarbon with a boiling point lower than the temperature at which the foam hardens. Examples of such hydrocarbons are Freon-11 or Freon-113 sold by 10 duPont. Hydrocarbons of this type can be added to and mixed with the acid solution, or they can be added separately at the time of mixing with the solid components. Non-fluorinated hydrocarbons with an appropriate boiling point can also be used, but are less desirable because of the associated risk of fire.

The manner of addition of these foaming agents in either dry or wet form may be a matter for the skilled person or may depend on various factors such as the nature of the desired product and / or the nature of the equipment used. Under certain circumstances, the method to be used can be determined by the nature of the foaming agent. For example, the carbonates react chemically with the acid solution; thus they cannot be added to the acid solution at an early stage in the reaction sequence. In contrast, the fluorinated hydrocarbons cause foaming by transition from a liquid to a gaseous state; they can thus be kept in contact with the acid solution if the temperature of the mixture remains sufficiently low. In the latter case, however, it should be recognized that the fluorinated hydrocarbons form a two-phase system with the acid solution. Therefore, care must be taken to ensure that the two-phase system is mixed evenly before the solids are mixed in.

Since the prior art describes a variety of materials which can be used in various ways to obtain the phosphate ceramics of the present invention, the term "foaming agents" as used herein is intended to include all such materials, provided that they lead to phosphate ceramic mics with the properties set forth above.

The following examples, in which all parts are reported as parts by weight, are intended to illustrate the advantages of the present invention.

5. EXAMPLES

Example 1

A phosphate foam was prepared from the following ingredients:

Parts per 10 Ingredient Weight (g) 100 parts CaSiOg A1203.3H20 14.42 36.04 85% H3P04 41.58 104.0 (61.6% P2 ° tj)

CaSiOg 40.0 100 15 Surfactant 0.04 0.1

If these ratios are converted by taking the metal oxide on an anhydrous basis and counting the water of hydration as part of the acid solution, the following picture is obtained:

Share per

Ingredient 100 parts CaSiOg

AlgOg 23.56 75.9% HgP04 116.5 25 (55% P205)

CaSiOg 100

Surfactant 0.1

The reaction solution was prepared by adding 1.04 parts Al 2 O 3 3H 2 O to 104 parts phosphoric acid and stirring the mixture under moderate agitation for 15 min until a clear solution was obtained. The surfactant (0.1 part) was added to the reaction solution which was then cooled to 4 ° C. The remaining dry ingredients (100 parts calcium silicate and 35 parts alumina trihydrate 35) were mixed together and placed in a continuous Readco processor. The reaction solution was also introduced into the Readco blender 8202362-16 through another inlet. The ingredients were mixed in proportion, deposited on a conveyor belt covered with a coating material and flattened. Foaming started to occur in about 1.5 min and the material mass became rigid in about 2 min. A continuous block of foamed material with a thickness of 25 mm and a width of 125 mm was obtained in this way . The foamed material 3 had a fine cell structure and a density of 288 kg / cm.

The compressive strength of this material according to ASTM D1621 was 4.2 kg / cm. The breaking modulus according to ASTM C209 was 4.9 kg / cm. No evidence of cracking was observed when 20 g cubes of the product were either placed in boiling water for half an hour and then dried or wetted with 50 g of water at room temperature and then dried.

Example 2

A phosphate foam was prepared from the same ingredients as used in Example 1. The reaction solution was prepared by adding 1.04 parts AljOg.S 2 O to 104 parts 20 phosphoric acid and stirring the mixture under moderate agitation for 15 hours. min until a clear solution was obtained. The surfactant (0.1 part) was then added to the reaction solution. The remaining dry ingredients (100 parts of calcium silicate and 35 parts of alumina trihydrate) were mixed together and placed in a continuous Readco processor. The reaction solution at a temperature of 22 ° C was also introduced into the Readco mixer through another inlet opening.

The ingredients were mixed proportionally therein, deposited on a conveyor belt covered with a coating material 30 and flattened. The foaming started to occur in about 42 s and the material mass became rigid in about 50 s. A continuous block of foamed material 25 mm thick and 125 mm wide was obtained in this way. The foamed material had a rough, irregular cell structure and a density of

35 272 kg / m. The compressive strength of this material was according to ASTM

D1621 3.5 kg / cm ^. The pressure modulus according to ASTM C209 was 3.5 kg / 2 cm. No indications of cracking were observed when 20 g cubes of the product were either placed in boiling water for 8202362 ½ - 17 hours and dried, or were wiped with 50 g of water at room temperature and then dried.

Example 3 A phosphate foam was prepared from the following ingredients:

Share per

Ingredient Weight (g) 100 parts CaSiO ^

Al203.3H20, 11.44 30.1 10 MgO (calcined) 3.0 7.9 80% H3PO4 43.56 114.63 (58.0% P2 ° 5)

CaSiO 3 38 100

Surfactant fabric 0.3 0.79 12mm long polyester fiber 0.2 0.53

If these ratios were converted by taking the metal oxide on an anhydrous basis and incorporating the water of hydration as part of the acid solution, the following picture was obtained:

Share per

Ingredient 100 parts CaSi03 A1203 19.7 25 MgO (calcined) 7.9 73.3% H3P04 125.05 (53.2% P205)

CaSiO 3 100

Surfactant 0.79 30 12mm Polyester Fiber 0.53

The reaction solution was prepared by adding 1.15 parts of Al2O3.3H2O to 114.63 parts of phosphoric acid and stirring the mixture under moderate agitation for about 15 minutes until a clear solution was obtained. The surfactant (0.79 part) was added to the reaction solution which was then cooled to 4 ° C. The other dry 8202362

1 V

V 18 components (100 parts of calcium silicate, 28.95 parts of aluminum oxide trihydrate, 7.9 parts of magnesium oxide and 0.53 parts of polyester fiber) were mixed together and placed in a continuous Readco processor. The reaction solution was also introduced into the Readco mixer through another feed port. The ingredients were mixed in proportion, poured onto a conveyor belt covered with a coating material and leveled. The foaming started in about 57 s and the material mass became rigid in about 1 min 51 s. A continuous block of foamed material 25 mm thick and 125 mm wide was obtained in this way. The foamed material had a fine cell structure and a density of 304 kg / m. The compressive strength of this material according to ASTM D1621 was 7 kg / cm.

2

The fracture modulus according to ASTM C209 was 5.6 kg / cm. No indications of cracking were observed when cubes of 20 g of the product were either placed in boiling water for half an hour and then dried, or were wetted with 50 g at room temperature and then dried.

Example 4 A phosphate foam was prepared from the following ingredients:

Share per

Ingredient Weight (g) 100 parts CaSiOg

Al203.3H20 16.0 40.0 25 85% HgP04 40.0 100.0 (61.6% P205)

CaSiOg 40.0 100.0

Surfactant 0.04 0.1

When these ratios were converted by taking the metal oxide on an anhydrous basis and counting the water of hydration as part of the acid solution, the following picture was obtained: 8202362 I - 19 - Parts per

Component 100 parts. CaSi03 A1203 26.15 74.7% H3P04 113.85 5 (54.1% P205)

CaSiO 3 100

Surfactant 0.1

The reaction solution was prepared by adding 5 parts of Al 2 O 3 .3H 2 O to 100 parts of phosphoric acid and stirring the mixture under moderate agitation for about 15 minutes until a clear solution was obtained. The surfactant (0.1 part) was added to the reaction solution, which was then cooled to 4 ° C. The remaining dry ingredients (100 parts of calcium silicate and 35 parts of alumina trihydrate) were mixed together and placed in a continuous Readco processor. The reaction solution was also introduced into the Readco mixer through another feed port. The ingredients were mixed proportionally in it.

20 lands on a conveyor belt covered with a coating material and flattened. Foaming started in about 1 min 45 s and the material mass became rigid in about 2 min 5 s. A continuous block of foam material with a thickness of 25 mm and a width of 125 mm was obtained in this way. The foam material 25 had a fine cell structure and a density of 464 kg / cm.

The compressive strength of this material according to ASTM D1621 was 8.4 kg / 2 cm. The fracture modulus according to ASTM C209 was 8.4 kg / cm. No evidence of cracking was observed when 20 g cubes of the product were either placed in boiling water for half an hour or wet with 50 g of water at room temperature and then dried.

Example 5

A non-foamed phosphate ceramic was prepared from the following ingredients; 35 8202362 * '- 20 -

Share per

Ingredient Weight (g) 100 parts CSi03

Al203.3H20 18.4 40.89 85% H3P04 39.6 88.0 5 (61.6% P205)

CaSiO 3 45.0 100

When these ratios were converted by taking the metal oxide on an anhydrous basis and counting the water of hydration as part of the acid solution, the following picture was obtained:

Share per

Ingredient 100 parts CaSiC> 3 A1203 26.73 73.2% H3P04 102.16 15 (53.1% P205)

CaSiC> 3 100

The reaction solution was prepared by adding 9.78 parts of 201203 · 3Η20 to 88 parts of phosphoric acid and stirring the mixture under moderate agitation for about 15 min until -20 to obtain a clear solution. The remaining dry ingredients (100 parts of calcium silicate and 31.1 parts of aluminum oxide trihydrate) were mixed together and placed in a continuous Readco processor. The reaction solution at room temperature was also introduced to the Readco mixer via another inlet opening. The ingredients were mixed in proportion, poured onto a conveyor belt covered with a coating material and flattened. No foaming occurred and the mixture set to a solid mass in 2 min 10 s. The hard ceramic-like material had a density of 30 960 kg / m3.

Example 6

A phosphate ceramic was prepared from the following ingredients; ; 8202362 - 21 -

Share per

Components Weight (g) 100 parts CaSiO ^ A1203.3H20 17.44 38.76 72% H3P04 40.56 90.13 5 (52.18% P205)

CaSiO 3 45 100

Vermiculite 4 8.89

When these ratios were converted by taking the metal oxide on an anhydrous basis and counting the hydration water as part of the acid solution, the following picture was obtained:

Share per

Ingredient 100 parts CaSi03 A1203 25.34 15 63% H3P04 103.55 (45.4% P205)

CaSiO 3 100

Vermiculite 8.89

The reaction solution was prepared by adding 7.65 parts of Al2 O3.3H2 O to 90.13 parts of phosphoric acid and stirring the mixture under moderate agitation for 15 min until a clear solution was obtained. The remaining dry ingredients (100 parts of calcium silicate, 31.11 parts of aluminum oxide trihydrate and 8.89 parts of vermiculite) were mixed together and placed in a continuous Readco processor. The reaction solution at room temperature (22 ° C) was also introduced into the Readco mixer through another feed port. The ingredients were mixed in proportion, poured onto a conveyor belt covered with a coating material and flattened.

No foaming occurred and the mixture set to a solid mass in 2 min 30 s. The hard ceramic-like material had a density of 944 kg / m.

Example 7

This example illustrates the use of a known dry foaming agent in combination with the present invention for the preparation of a ceramic phosphate material. A phospho-8202362-22-phate foam was prepared from the following ingredients:

Share per

Components Weight (g) 100 parts CaSiOg A1203.3H20 8.97 17.94 5 68% H3P04 (49.3% P205) 56.03 112.06

CaSiO 3 50.00 100.0

MgCO 3 2.0 4.0

MgO (calcined) 7.0 14.0 10 Talc filler 10.0 20.0

When these injuries were converted by taking the metal oxide on an anhydrous basis and counting the water of hydration as part of the acid solution, the following picture was obtained: - 15 parts per

Ingredient 100 parts CaSiOg A1203 11.72 64.4% H3P04 (46.7% PgOg) 118.27 20 CaSiOg 100

MgCOg 4.0

MgO (calcined) 14.0

Talc filler 20.0

The reaction solution was prepared at room temperature by adding 17.94 parts of Al 2 O 3 3H 2 O with stirring to 112.06 parts of phosphoric acid solution. The clear solution obtained was cooled to 13 ° C. The remaining dry ingredients (100 parts of calcium silicate, 4.0 parts of magnesium carbonate, 14.0 parts of magnesium oxide and 20.0 parts of filler) were mixed together and placed in a continuous Readco processor. The reaction solution at a temperature of 13 ° C was also introduced into the Readco mixer through another feed opening. The ingredients were mixed proportionally therein, and then poured onto a conveyor belt covered with a coating material. Due to the presence of the acid in the mixture, foaming occurred as soon as the material had left the mixer. The foaming material was equalized to 8202362; - 23 - and it solidified in about 1 min 30 s, after which another exotic reaction occurred for 30 s, as evidenced by the release of steam. The rigid foamed material had a fine cell structure and a density of 192 kg / m. The compressive strength of this material according to ASTM D1621 was 6.3 kg / cm 2 and the pressure modulus according to ASTM C209 was 2.8 kg / cm. This material floated on water, indicating that the water could not so easily enter the foam matrix.

Example 8 This example illustrates the use of a known liquid foaming agent for the preparation of the phosphate ceramic of the present invention. A phosphate ceramic was prepared from the following ingredients:

Parts per 15 Ingredient Weight (g) 100 parts GaSiOg.

Al2 O3 9.0 18.0 80.2% H3 PO4 (58.2% P205) 53.0 106.0

CaSiO3 50.0 100.0 20 Freon-11® 4.0 '8.0

MgO (calcined) 5.0 10.0

Talc filler 10.0 20.0

When these ratios were converted by taking the metal oxide on an anhydrous basis and using the water of hydration as part of the acid solution, the following picture was obtained:

Share per

Ingredient 100 parts CaSi03 A1203 11.8 30 75.8% H3P04 112.2 (55% P205)

CaSiO 3. 100.0

Freon-11® 8.0

MgO (calcined) 10.0 35 Talc filler 20.0

The reaction solution was prepared at room temperature 8202362 - 24 - by mixing 10 parts of A 2 O 2 S 2 O with stirring with 106.0 parts of phosphoric acid solution and the reaction was cooled to 13 ° C. The remaining dry ingredients (100 parts of calcium silicate, 8.0 parts of alumina trihydrate, 10.0 parts of magnesium oxide and 20.0 parts of filler) were mixed together and placed in a continuous Readco processor. The ingredients were mixed proportionally, with the Freon-11 added via a separate direct mixer to obtain a good dispersion. The mixed material was removed from the mixer and foaming occurred slowly over a 3 min period. Curing occurred in 4 min, and the exothermic reaction occurred in 4.5 min. The coarse cell structure foam obtained had a density of 304 kg / m.

* i 8202362

Claims (77)

Process for the preparation of rigid, water-resistant ceramic phosphate material, characterized in that a metal oxide is prepared containing 11-65 parts by weight, calculated on an anhydrous basis, of at least one metal oxide from the group consisting of Al2O3, MgO, CaO, ZnO and the hydrates thereof, that a reaction solution is prepared containing a portion of the metal oxide and 80-190 parts by weight of a phosphoric acid solution with the equivalent by weight of the acid solution of 35-75% by weight % phosphorus pentoxide, the hydration water of the metal oxide being included in the calculation of the phosphorus pentoxide content, that a mixture is prepared containing the remainder of the metal oxide and 100 parts by weight of calcium silicate, that the temperature of the reaction solution is at a desired value it is stated that the mixture is mixed proportionally with the reaction solution, and that the obtained mixed material is brought into a desired shape and the compo its components are allowed to react, the amount of metal oxide used for the preparation of the reaction solution, and the temperature of the reaction solution being selected to predetermine approximately the time at which the mixed material becomes rigid with respect to the time when evaporation of the water occurs. 2. Process according to claim 1, characterized in that 13-26 parts of metal oxide, 100 parts of calcium silicate and 90-150 parts of phosphoric acid solution with the equivalent of 40-70% phosphorus pentoxide are used. Process according to claim 1, characterized in that 15-22 parts of metal oxide, 100 parts of calcium silicate and 100-130 parts of phosphoric acid solution with the equivalent of 45-65% phosphorus pentoxide are used. Process according to claims 1-3, characterized in that the temperature of the reaction solution is 2-27 ° C. Process according to claims 1-3, characterized in that the temperature of the reaction solution is 8202362-26-3-7 ° C. 6. Process according to claims 1-3, characterized in that the temperature of the reaction solution is 4.5 ° C. 7. Process according to claims 1-3, characterized in that the particle size of the metal oxide does not exceed 0.043 mm (325 mesh Tyler Standard) and the particle size of the calcium silicate does not exceed 0.074 mm (200 mesh Tyler Standard). 8. Process according to claims 1-3, characterized in that the metal oxide is alumina trihydrate. Process according to claims 1-3, characterized in that the metal oxide is magnesium oxide. 10. Process according to claims 1-3, characterized in that the metal oxide contains a mixture of alumina trihydrate and magnesium oxide. 11. Water-resistant ceramic phosphate product obtained using the method according to any one of claims 20 1-10. Product according to claim 11, characterized in that the product has a foam structure. Product according to claim 11, characterized in that the product has a non-foamed structure. Product according to claim 13, characterized in that the product comprises a filler. Method according to claims 1-3, characterized in that the reaction solution contains a surfactant. 16. A method according to claims 1-3, characterized in that the mixture contains fibrous reinforcing material. Method according to claims 1-3, characterized in that the mixed material contains a foaming agent 35. Process according to claim 17, characterized in that the blowing agent is a carbonate from the group of MgCOg, CaCOg, ZnCOg and Li2COg. 19. Process according to claim 17, characterized in that the blowing agent is a fluorinated hydrocarbon with a boiling point lower than the temperature at which the mixed material becomes rigid. 20. Process for the preparation of rigid, water-resistant ceramic phosphate material, characterized in that a mixture is prepared containing 11-6.5 parts by weight, calculated on an anhydrous basis, of at least § n metal oxide from the group consisting of A-Og, MgO , CaO, ZnO and its hydrates, and 100 parts by weight of calcium silicate, a reaction solution is prepared containing 80-190 parts by weight of a phosphoric acid solution with the equivalent based on the weight of the acid solution of 35-75% by weight. % of phosphorus pentoxide, the hydration water of the metal oxide being included in the calculation of the phosphorus pentoxide content, that the temperature of the reaction solution is adjusted to a desired value, that the mixture is mixed proportionally with the reaction solution, and that resultant mixed material is shaped and its compounds are allowed to interact, the temperature of the reaction solution being selected as such that approximately the time is determined at which the mixed material becomes rigid relative to the time at which evaporation of the water occurs. A method according to claim 20, characterized in that. Note that 13-26 parts by weight of metal oxide, 100 parts by weight of calcium silicate, and 90-150 parts by weight of phosphoric acid solution with the equivalent of 40-70% phosphorus pentoxide are used. A method according to claim 20, characterized in that 15-22 parts of metal oxide, 100 parts of calcium silicate, and 100-130 parts of phosphoric acid solution with the equivalent of 45-65% phosphorus pentoxide are used. A method according to claims 20-22, characterized in that the temperature of the reaction solution is 2-26 ° C. 24. Process according to claims 20-22, characterized in that the temperature of the reaction solution is 3-7 ° C 8202362-28-4. 25. Process according to claims 20-22, characterized in that the temperature of the reaction solution is 4.5 ° C. 26. A process according to claims 20-22, characterized in that the particle size of the metal oxide does not exceed 0.043 mm (325 mesh Tyler Standard) and the particle size of the calcium silicate does not exceed 0.074 mm (200 mesh Tyler Standard). 27. A method according to claims 20-22, characterized in that the metal oxide is alumina trihydrate. 28. A method according to claims 20-22, characterized in that the metal oxide is magnesium oxide. 29. A process according to claims 20-22, characterized in that the metal oxide contains a mixture of alumina trihydrate and magnesium oxide. 30. A water-resistant ceramic phosphate product obtained using the method according to any one of claims 20-29. -31. Product according to claim 30, characterized in that the product has a foam structure. Product according to claim 30, characterized in that the product has a non-foamed structure. 33. A product according to claim 32, characterized in that the product comprises a filler. 34. Process according to claims 20-29, characterized in that the reaction solution contains a surfactant. A method according to claims 20-29, characterized in that the mixture contains a fibrous reinforcing material. A method according to claims 20-29, characterized in that the mixed material contains a foaming agent 35. The process according to claim 36, characterized in that the blowing agent is a carbonate from the group of MgCO 3, CaCO 3, ZnCO 3 and Li 2 CO 3. 38. Process according to claim 36, characterized in that the foaming agent is a fluorinated hydrocarbon with a boiling point lower than the temperature at which the mixed material becomes rigid. 39. Process for the preparation of a rigid, water-resistant 5-ceramic phosphate material, characterized in that a metal oxide is prepared containing 11-65 parts by weight, calculated on an anhydrous basis, of at least one metal oxide from the group consisting of A 2 O 2, MgO, CaO, ZnO and its hydrates, a reaction solution is prepared containing a portion of the metal oxide and 80-190 parts by weight of a phosphoric acid solution with the equivalent based on the weight of the acid solution of 35-75 wt.% phosphorus pentoxide, the hydration water of the metal oxide being included in the calculation of the phosphorus pentoxide content, that a mixture is prepared containing the remainder of the metal oxide and 100 parts by weight of calcium silicate, that the mixture is mixed proportionally with the reaction solution , and that the resulting mixed material is shaped into a desired shape and its components are allowed to interact, wherein the amount of metal oxide, such as e is used for the preparation of the reaction solution, so that it is approximately determined in advance the time at which the mixed material becomes rigid relative to the time at which evaporation of the water occurs. 40. Process according to claim 39, characterized in that 13-26 parts of metal oxide, 100 parts of calcium silicate, and 90-150 parts of phosphoric acid solution with the equivalent of 45-70% phosphorus pentoxide are used. 41. A method according to claim 39, characterized in that 15-22 parts of metal oxide, 100 parts of calcium silicate, and 100-130 parts of phosphoric acid solution with the equivalent of 45-65% phosphorus pentoxide are used. A method according to claims 39-41, characterized in that the particle size of the metal oxide does not exceed 0.043 mm (325 mesh Tyler Standard) and the particle size of the calcium silicate does not exceed 0.074 mm 40 (200 mesh Tyler Standard). 8202362 • c- 4 -30 '- 43. Procedure. according to claims 39-41, characterized in that the metal oxide is alumina trihydrate. A method according to claims 39-41, characterized in that the metal oxide is magnesium oxide. 45. A process according to claims 39-41, characterized in that the metal oxide comprises a mixture of alumina trihydrate and magnesium oxide. 46. Water-resistant ceramic phosphate product obtained by using the method according to any one of claims 39-45. 47. A product according to claim 46, characterized in that it has a foam structure. 48. A product according to claim 46, characterized in that the product has a non-foamed structure. 49. A product according to claim 48, characterized in that the product comprises a filler. 50. A process according to claims 39-45, characterized in that the reaction solution contains a surfactant. 51. A method according to claims 39-45, characterized in that the mixture comprises fibrous reinforcing material. 52. A method according to claims 39-45, characterized in that the mixed material comprises a foaming agent. 53. A process according to claim 52, characterized in that the blowing agent is a carbonate from the group consisting of MgCOg, CaCO3, ZnCO3 and Li2CO3 · 54. A process according to claim 52, characterized in that the blowing agent is a fluorinated hydrocarbon with a boiling point lower than the temperature at which the mixed material becomes rigid. 55. A composition for providing a rigid, water-resistant ceramic phosphate material, characterized in that the composition comprises: 11-65 parts by weight calculated on an anhydrous basis of at least one metal oxide from the group consisting of Al2O3, MgO, CaO , ZnO and its hydrates; 40 80-190 parts by weight of phosphoric acid solution with the equivalent based on the weight of the acid solution of 35-75% by weight of phosphorus pentoxide, which includes the hydration water of the metal oxide in the calculation of the phosphorus pent- oxide content, and 100 parts by weight of calcium silicate. 56. A composition according to claim 55, characterized in that it contains 13-26 parts of metal oxide, 100 parts of calcium silicate, and 90-150 parts of phosphoric acid solution with the equivalent of 40-70% phosphorus pentoxide. 57. A composition according to claim 55, characterized in that it contains 15-22 parts of metal oxide, 100 parts of calcium silicate, and 100-130 parts of phosphoric acid solution with the equivalent of 45-65% phosphorus pentoxide. 58. A composition according to claims 55-57, characterized in that the particle size of the metal oxide does not exceed 0.043 mm (325 mesh Tyler Standard) and the particle size of the calcium silicate does not exceed 0.074 mm (200 mesh Tyler Standard). ). 59. A composition according to claims 55-57, characterized in that the metal oxide is alumina trihydrate. 60. A composition according to claims 55-57, characterized in that the metal oxide is magnesium oxide. 61. A composition according to claims 55-57, characterized in that the composition comprises a mixture of alumina trihydrate and magnesium oxide. A composition according to claims 55-57, characterized in that the composition comprises a surfactant. 63. A composition according to claims 55-57, characterized in that it comprises a fibrous reinforcement material. 64. A composition according to claims 55-57, characterized in that it comprises a foaming agent. 65. A composition according to claim 64, characterized in that the foaming agent is a carbonate from the group of MgCO 2, CaCO 2, ZnCO 2 and 10 CO-1. A composition according to claim 64, characterized in that the foaming agent is a fluorinated hydrocarbon having a boiling point lower than the temperature at which the mixed material becomes rigid. 67. Rigid, water-resistant ceramic phosphate material, obtained by reacting (1) 11-65 parts by weight calculated on an anhydrous basis of at least one metal oxide selected from the group consisting of Al 2 O 3, MgO, CaO, ZnO and its hydrates; (2) 80-190 parts by weight of a phosphoric acid solution having the equivalent based on the weight of the acid solution of 35-75% by weight of phosphorus pentoxide, the hydration water of the metal oxide included in the calculation of the phosphorus pentoxide content; and (3) 100 parts by weight of calcium silicate. 68. Phosphate material according to claim 67, characterized in that 13-26 parts of metal oxide, 100 parts of calcium-15 silicate and 90-150 parts of phosphoric acid solution with the equivalent of 40-70% phosphorus pentoxide are used. 69. Phosphate material according to claim 67, characterized in that 15-22 parts of metal oxide, 100 parts of calcium silicate and 100-130 parts of phosphoric acid solution with the equivalent of 45-65% phosphorus pentoxide have been used. 70. Phosphate material according to claims 67-69, characterized in that the ceramic material is obtained by reaction of a reaction solution and a component mixture, the reaction solution containing the phosphoric acid solution and at least a part of the metal oxide and the component mixture the calcium silicate and the rest of the metal oxide. 71. Phosphate material according to claims 67-69, characterized in that the amount of metal oxide used for the preparation of the reaction solution and the temperature of the reaction solution are chosen such that approximately the time at which the mixed material becomes rigid relative to the time when water evaporates. The phosphate material according to claim 71, characterized in that the particle size of the metal oxide does not exceed 0.043 mm (325 mesh Tyler Standard) and the particle size of the calcium silicate does not exceed 0.074 mm (200 mesh Tyler Standard). 8202362 * - - 33 - * · 73. A phosphate material according to claim 71, characterized in that the metal oxide is alumina trihydrate. The phosphate material according to claim 71, characterized in that the metal oxide is magnesium oxide. 75. A phosphate material according to claim 71, characterized in that the metal oxide comprises a mixture of alumina trihydrate and magnesium oxide. 76. A phosphate material according to claim 71, characterized in that the ceramic material comprises a surfactant. A phosphate material according to claim 71, characterized in that the ceramic comprises a fibrous reinforcement material. 78. A phosphate material according to claim 71, characterized in that it comprises a foaming agent. A phosphate material according to claim 78 including the. Note that the foaming agent is a carbonate from the group consisting of MgCOg, CaCOg, ZnCOg, and Id ^ COg. 80. A phosphate material according to claim 78, characterized in that the foaming agent is a fluorinated hydrocarbon having a boiling point lower than the temperature at which the mixed material becomes rigid. 25 8202362