DE1295461B - Process for the production of foamed macrofiber structures - Google Patents

Description

1 2

The production of foamed structures (foam up to 600 percent by weight, based on the clay, substances) using foaming agents from Such macro-fiber concentrations contribute to a Alumina is, for example, from the German patent particularly desirable consistency of the aqueous, Writings 866024, 881628 and from silicates, foamable mixtures. for example from "Silikattechnik", 1960, p. 28, known. 5 The production of foamable mixtures From the German patent specification 928 039 a can be done simply by the fact that the individual Process for the production of porous insulating materials Using pulps and binders stirred until they are evenly dispersed, gas-releasing agents known, according to the plaster of paris The preferred order of mixing is that, or other rapidly setting substances and clay or io that an alumina sol is first produced and then certain aluminum silicates and a propellant to the other ingredients are added, to inorganic substances distributed in water.

will give. After shaping and drying according to the range from 5.5 to 7.5 used the material is fired. most appropriate at the beginning on the alumina sol,

The invention relates to a method for bringing this to the desired pH value Manufacture very versatile, foamed is. For the pH adjustment you can use diluted Macrofibre structures with a low bulk density due to alkalis, such as ammonium, sodium, potassium or Foaming and drying of aqueous mixed lithium hydroxide, as well as organic ones, in water genes that use macrofiber, clay, and foaming agent soluble bases such as triethanolamine included, which is characterized in that 0.5 ao.

up to 10 percent by weight of fibrous clay, based on the aqueous, foamable mixtures

on the mixture to be foamed, in water di- according to numerous known methods in foamed spergiert, the pH of the suspension obtained can be transferred to structures. For example, can 5.5 to 7.5 adjusted, and the suspension with 200 the mixtures mechanically by vigorous agitation, up to 1000 percent by weight of macrofibers, based on the 25 through a stirrer, mixer or through the clay, being mixed; whereupon 1 to 10 Gesa produced a commercially available foamer weight percent based on the alumina, perfluoro- can be foamed, octane, ß-H-Perfluorpelargon-, Capryl-, Pelargon-,. To improve this, additional caprine, Undecyl, lauric, tridecyl, myristic, substances are added. For example, color pentadecyl, 10-UndecyIen-, p-Octylbenzoe-, Cyclo- 30. materials, fillers or binders, such as hydroxyethylhexylbutyric acid, Mixtures of these acids, their cellulose, because of the beneficial properties that Salts, long-chain alkylbenzenesulfonic acids, which they impart to the mixtures, are added. Suitable Salts, salts of substituted, hydrolyzed protein organic binders are for example: polyacids, Dioctyl sodium sulfosuccinate, sodium lauroyl vinyl acetate, phenol-formaldehyde resins, urea sarcosinate, Fluoroalkyl phosphates or ester salts of formaldehyde resins and melamine-formaldehyde long chains Alcohols with sulfuric acid added resins. Of particular importance as additives are foamed, the mixture and the obtained in foamed glass fiber structures are phenols Foam is dried. According to the invention, formaldehyde resins. The dried, foamed Reversible, fibrous clay is for example that can be used as such or in structures the USA. Patent 2915475 described fase- 40 for example impregnated with resins and then Alumina monohydrate or finest colloidal ones are pressed. Other additives are for the Boehmite fibrils. Obviously an expert.

The Macrofibers Usable According to the Invention The foamed macrofibre structures can be can be any material that can be dried into visible formations that are represented by number-fiber form is present. To give these fibers from the fiber-rich 45 favorable properties, such as sound absorption, to differentiate between clay, they are used here as heat-insulating properties, excellent "Macrofibers" called. Suitable macrofibers · absorbency, low density, resilience, are for example: paper pulp, bleached and un- strength, stiffness or flame resistance, faded Wood pulp, asbestos fiber, fiberglass, draw. The ge-metal fibers produced according to the invention, Mineral fibers such as rock wool and foamed macrofiber structures can be varied Send slag wool and synthetic inorganic uses, for example, can fibers, like kaolin fibers. Use them as gas filter materials, shock-resistant packaging

Besides the fibrous clay and the maceration material, acoustic and thermal insulating fibers according to the invention, so-called »foams are used as bottom cardboard, etc., coactanten «are used, which can be used for foaming The availability of the aqueous clay-macrofiber mixture in the process according to the invention varies are essential. that structures with particularly desirable

If the coactants are obtained in the form of their salts, properties. For example, könwendet are for example the ammonium, NEN by changing the ratio of MakroNatrium-, potassium, lithium, and organic amine ⁶ ° fibers to alumina, the total concentration of salts suitable. Made of clay and water content

According to the invention, preferred amounts of clay whose bulk density ranges from less than 8 to from 1 to 5 percent by weight, based on which to more than 80 kg / m ³ . At the same time, the mixture can be foamed. Such alumina concentrations - the fire resistance, strength, stiffness and trations lead to the most favorable consistency of the 65 the springback to almost any desired grain-aqueous mixture with a view to easy combination of properties. When miscibility and foamability. the ratio of macrofibers to clay between

Preferred amounts of macrofiber range from 200 approximately 3: 1 and 6: 1 for total alumina

Concentration is kept from 1 to 5%, structures can be produced that have the greatest degree of Have springback, good strength and good heat insulating properties.

5 Example 1

15 parts of fibrous alumina monohydrate are dispersed in 340 parts of water in an "Osterizer mixer" and the pH is adjusted to 7.0 with dilute ammonium hydroxide solution. The mixture is placed in a Hobart mixer kettle and stirred at moderate speed, while 135 parts of chopped synthetic mineral fibers consisting of Al ₂ O ₃ , SiO ₂ and a little B ₂ O ₃ and Na ₂ O, 200 parts of water and a portion of 0.75 parts of sodium lauryl sulfate in 10 parts of water are added. The sodium lauryl sulfate is intended to partially foam and disperse the fibers. After the rest of the sodium lauryl sulfate has been added, the system is switched to a high stirring speed. The whole kettle fills with foam, which is dried in an oven in the form of a block at 100 ° C. A homogeneous structure with a density of 48 kg / m ^{s is obtained} .

Example 2

20 parts of fibrous alumina monohydrate (very fine, colloidal fibrils made from boehmite) are dispersed in 380 parts of water in an "Osterizer mixer" and the pH is adjusted to 6.0 with dilute potassium hydroxide solution. To the mixture are slowly added 60 parts of fibrous potassium titanate, with enough water being added that a uniform, creamy mixture is formed. This is then placed in a "Hobart mixer" kettle and stirred at a moderate speed while 0.6 part of perfluorooctanoic acid in ethanol solution is added. After a few minutes, the stirring speed is switched to high. A very voluminous foam develops. When drying at HO ⁰ C, a light block of this composition is formed, the density of which is 109 kg / m ^s .

Example 3

25 parts of the fibrous clay monohydrate used in Example 2 are dispersed in 475 parts of water in an "Osterizer mixer" and the pH is adjusted to 6.5 with dilute ammonium hydroxide. 25 parts of a phenol-formaldehyde resin are slowly added to the sol; the resin is emulsified into a creamy, uniform emulsion. The mixture is placed in a 4-1 Hobart mixer kettle and stirred at a moderate speed while 100 parts of glass fibers are added. As much water is added as is needed for smooth mixing. 1.25 parts of ammonium laurate in 10 parts of water are added with the glass fibers to allow the fibers to disperse evenly as the foaming progresses. The foam is developed at high speed. When a foam block is dried at 100 ^° C., a coherent structure with a density of 32 kg / m »is created.

Example 4

10 parts of the clay monohydrate used in Example 2 are in 490 parts of water in one "Osterizer mixer" is dispersed to a 2% sol, and the pH is adjusted with dilute ammonium hydroxide set to 7.0. The sol is then placed in a Hobart mixer kettle and combined with a Wire mixer stirred while 171 parts of wet, unbleached Kraft wood pulp (57 parts on a dry weight basis) be added. A 0.3 part portion of sodium lauryl sulfate is added to this mixture added to water to cause partial foaming and dispersion of the wood fibers. Of the remaining coactant is then added and the mixture is whipped for about 10 minutes. A stiff foam develops.

The foamed mixture is dried for 16 hours in an oven at 100 ⁰ C and results in a lightweight refractory mixture containing 15% alumina monohydrate and excellent thermally insulated at low temperatures.

Example 5

Following the procedure of Example 4, 20 parts of the alumina monohydrate used in Example 2 are obtained in 480 parts of water at a pH adjusted to 7.0 with 294 parts of wet, bleached Kraft pulp (98 parts on a dry weight basis) and 1.0 part ammonium caprate in mixed aqueous solution.

The foamed mixture turns into a refractory, 17% clay containing in the form of thin sheets Dried material that is suitable as a shockproof packaging material.

Example 6

40 parts of the alumina monohydrate used in Example 2 become one in 460 parts of water 8% sol dispersed. The pH of the sol is adjusted to 5.5 with dilute sodium hydroxide. Following the procedure of Example 4, 480 parts of wet, bleached Kraft pulp (160 parts on dry weight basis) and 0.75 parts of myristic acid dissolved in isopropanol, along with the Alumina monohydrate sol dispersed. Then the mixture is foamed.

The foamed mixture is as in Example 4 in the form of 1.27 cm thick blocks to a refractory, Material suitable for acoustic tiles containing 20% alumina monohydrate, dried.

Example 7

10 parts of fibrous alumina monohydrate are dispersed in 490 parts of water to form a 2% strength sol. The pH of the sol is adjusted to 7.0 with a dilute, aqueous triethanolamine solution. 270 parts of wet, bleached kraft pulp (90 parts on a dry weight basis) and 9.2 parts of lauric acid Dissolved in iospropanol are mixed with the alumina sol as in Example 4. The mixture is then foamed as in Example 4.

The foamed structure is pressed into thin sheet form and made into a 10% clay containing Structure that gives off a well-absorbing blotting paper, dried.

Example 8

10 parts of the alumina monohydrate used in Example 2 are dissolved in 490 parts of water 2% sol dispersed. The pH of the sol is adjusted to 7.0 with dilute potassium hydroxide.

I 295

The mixture is then placed in a Hobart mixer kettle and stirred with a wire mixer, while 270 parts of wet, unbleached sulfite pulp (90 parts on a dry weight basis) and 0.3 parts Sodium lauryl sulfate can be added as an aqueous solution to the clay monohydrate. The mixture is foamed.

The foamed mixture is used as a covering agent between crop rows and on and around sensitive plants, shrubs and trees are placed to protect against freezing.

Claims (1)

Claim: Process for the production of foamed macrofiber structures with a low bulk density Foaming and drying of aqueous mixtures containing macrofibers, clay and foaming agents, characterized in that that 0.5 to 10 percent by weight of fibrous clay, based on the foam to be foamed Mixture, dispersed in water, the pH of the suspension obtained to 5.5 to 7.5 set and the suspension with 200 to 1000 percent by weight of macrofibers, based on the clay, being mixed; whereupon 1 to 10 percent by weight, based on the clay, perfluorooctane, ß-H-perfluoropelargon, caprylic, pelargon, Capric, undecyl, lauric, tridecyl, myristic, pentadecyl, 10-undecylene, p-octylbenzoic, Cyclohexylbutyric acid, mixtures of these acids, their salts, long-chain alkylbenzenesulfonic acids, their salts, salts of substituted, hydrolyzed protein acids, dioctyl sodium sulfosuccinate, Sodium lauroyl sarcosinate, fluoroalkyl phosphates or ester salts of long chain Alcohols with sulfuric acid are added, the mixture is foamed and the obtained Foam is dried.