DE2716152C2 - Vermiculite lamellar product, process for its manufacture and its use - Google Patents

Description

The invention relates to chemical delamination Vermiculite flake product formed from vermiculite particles. a method for its production according to the preamble of claim 4 and its use as a fire-proof and / or soundproofing cndc .Layer board in the construction industry.

Vermiculite, a phyllosilicate mineral, can be left out through contamination aqueous salt solutions are made to swell chemically, whereupon the layer structure on mechanical way into extremely thin vermiculite lamellae can be peeled.

From GB-PS lü 16 385 are the formation of an aqueous Suspension of vermiculite lamellae by chemical swelling and mechanical exfoliation (under effect of shear forces) of vermiculite particles Niiwic the production of solid molded bodies from this Suspension known by application to a surface and evaporation of the water. The cohesion The test form body is achieved by the fact that the individual Vermilculite lamellas overlap each other and exert mutual forces of attraction.

Is is also known. Leakage particles through influence to peel open from heat under the formation of flaky grains. In these vermiculite granules obtained by heating the vermiculite has a low density. Inside each vermiculite granule that was before exfoliating was a separate vermiculite particle, the vermiculichiae separate from each other during heating separated but remain practically parallel to each other. In addition, such a structure only exists within of each vermiculite granule and does not extend into a continuous structure between vermiculite granules. Solid moldings made from such vermiculite particles are also known which also contain sodium silicals included as a binder.

It is an object of the invention to provide a vermiculite lamellar product to make available according to the preamble of Palent claim I, in the form of a foam is present.

This object is achieved by the vermiculite lamella product characterized in claim 1. solved.
Other phyllosilicate minerals, such as hydrobiotite or chlorite vermiculite, also contain a significant proportion of vermiculite layers. and its layer structure can also be exfoliated in the same or similar manner as the layer structure of vermiculite itself. These phyllosilicate crystals containing vermiculite layers likewise result in thin lamellae and can be used for the production of the inventive micro-miculite lamellar product, but particles of vermiculite itself are preferred for the production of the foam according to the invention.

The vermiculite lamella product according to the invention is in the form of a cell insert. its target walls of overlapping, individual vermiculilla cells, which are joined together by mutual forces of attraction.

J5 are held, exist and are not brittle Form foam.

The cell structure extends continuously and practically evenly in all dimensions through the volume of the foam formed. The individual vermiculite lamellae are in all of the cell structure as a whole possible orientations to a given reference plane.

The above-mentioned individual vermiculite lamps For example, platelets or flakes have a smallest dimension below 0.5 µm. preferably below 0.05 µm and in particular below 0.005 µm and have approximately the same length and breadth dimensions of at least 100 times. preferably at least 100 times. the smallest dimension.

The cell structure of the vermiculite lamellar product according to the invention preferably has a density of not more than 0.5 g / cm ¹ and in particular not more than 0.15 g / cm ', and the density can be, for example, down to 0.01 g / cm' for particularly light foams.

The density can be varied in different catfish, for example by introducing different amounts of gas into the suspension or the solids content the suspension changes. For a low density foam, the solids content is suitably 5

µ to 20% by weight. while the solids content of up to 30 percent of a higher density foam - may be increased% or above..

A particular embodiment of the invention consists in the method characterized in claim 4

For the manufacture of a vermiculite lamella product according to the invention.

The swelling and exfoliation of vermiculite with the formation of aqueous suspensions of Vcrmlculllla-

nielle lsi from various publications, for example from OB-PS 10 16 385, 10 76 786 and Il 19 305 as well as from the article by Baumeister and Hahn in "Micron", 7, 247 (1976), known. The methods known from these publications are at 5 the implementation of the method according to the invention applicable, but is in the foam formation after Process according to the invention preferably a surfactant or foaming agent in the suspension before the gas is introduced into the suspension to form the foam, whereby under "foam" is to be understood as an expanded form of the whole suspension.

Suitably a surfactant or foaming agent is selected which is incorporated into the structure of the vermiculite mineral able to penetrate and thereby cause the vermiculite mineral to swell and peel brings. It is particularly preferred to use a kaiionischen, organic salt, which leads to an ion exchange with the cations present in the vermiculite layers. Particularly preferred canonical, surface-active center! are the surface-active ones Agents containing hydrocarbon-substituted ammonium cations contain. For example, I to 4 hydrogen atoms of the ammonium cation can be replaced by alkyl, Aryl, alicyclic or heterocyclic groups.

Examples of preferred cationic salts are:

n-bulylammonium chloride,

Isobulylammonium chloride,

Isoamylammoniumchlorld,

Ceiylpyridlniumbroiiild,

CelyltrimethylammoniumbroE-fid, 2-ethylhexylammonium chloride ,.

Dodecylammonium chloride,

Lysine monohydrochloride,

Ornithine monohydrochloride and

Polypeptides

in cationic form. Other types of foaming * o means or foam-producing surface-active agents, for example langkeltige, aliphalische alcohols such as cetyl alcohol, Alkylsulfalsalze as Natriumlaurylsulfal, N-Acylsarcoslnate and long chain aliphalische amine oxides such as Oleyldimcthylamin-N-oxide, can be * ^s of the suspension of Vermiculillamellen as Additives for other swelling agents, for example for alkali chlorides, or in combination with the above-mentioned cationic salts can be added.

An alternate class of foaming agents, appropriately that can be added to the suspension of vermiculite amelia are those as foaming agents known proteins, for example water-soluble proteins (such as albumin or gelatin) or water-soluble made protein derivatives such as hydrolyzed soybeans, '5 hydrolyzed blood or feathers.

The liquid suspension medium, if it is an aqueous medium, can contain water-miscible, organic liquids, for example the lower alcohols or acetone. Alternatively, the foam can be formed in a non-aqueous medium using modified vermiculite, as known from CiB-PS IO 7fi 786 .

In order to form foam, the suspension formed is added A gas or steam is cinged from the peeled-off lamellas. The gas is preferably the aqueous solution Suspension towards inert. For example, I.uli. Nitrogen. Argon. Carbon dioxide, a carbon

30th

35 hydrogen, chlorinated hydrocarbons, fluorocarbons or chlorofluorocarbons. It is particularly advantageous to introduce the gas mechanically into the suspension by rapid movement, for example by rapid piping or beating the suspension. Alternatively, the suspension can be heated rapidly and the foam formed by the generation of gas either in the form of steam formed by evaporation of water or from gas dissolved in the sample that is released.

The inventive (3e vermiculite lamella product (hereinafter also referred to as vermiculite foam) is a foam in the form of a two-phase dispersion of gas in a solid phase, where the solid Phase is an essentially continuous, inorganic cell structure. In the foam can be small Amounts of organic materials that are either intentionally added or unintentionally present, to be available. The presence of such an organic material is essential for holding the cell structure together not necessary, but can modify its properties as desired. By the distance of water from an aqueous suspension of vermiculite amelia from which a foam has been formed is, the lamellas come together and form a coherent film. Hence, the cell walls preserve of the cell structure of the inventive! Vermiculilla lamellar product their mechanical strength largely or entirely in that the vermiculite amelias stick together on their own when the water is removed will. The cell structure formed is a non-brittle foam, i. H. under stress, the cell structure deformed without crumbling.

The vermiculite lamella product according to the invention, present in the form of a cell structure, is a valuable one heat-resistant and heat-insulating material that is used to fill cavities or as a coating on the Outside of materials such as wood or chairs can be used, in both cases the vermiculite foam and others. ai :: fire protection layer works. The Vermiculiischaumsioff can be in the form of plates for subsequent processing or the manufacture of laminates. The vermiculite foam can, for example, as Inner layer of a composite component with outer layers made of, for example, wood veneer, paper, asbestos. Mica, plastic or vermiculifoil can be used, and Such composite components can be used as decorative panels. The vermiculite foam can also be used in Laminates as an inner layer between plasterboard or foils made of thermosetting resin, for example Melamine resin. Such laminates can be used in the construction industry as refractory and / or Sound-insulating laminated panels that are kept at temperatures of around 1000 ° C without disintegrating can be used. Layers of vermicular foam can be used as a lamination process Top surfaces are applied to sheets of polyurethane foam to improve the fire resistance of the polyurethane foam core to improve. The foam, d. H. the gaseous suspension of exfoliated vermiculilla milk before drying, can be used appropriately are to be made to previously formed vermiculite amelia products, for example foils or sheets made of already dried vcrmlculllschaumsloff. to each other / u hindcn. so that several foils are glued together and / and larger objects are worked on in the same way Wise, through the action of heat,

Put vermiculite together with the same foam are glued, so that a composite component is formed which the vermiculite foam according to the invention as a continuous binder between granules made of flaked by the action of heat Contains vermiculite.

For some purposes it may be necessary to make the vermiculite foam waterproof, for example by subjecting it to an ammonia treatment as described in the UK patent application 14 551/77 (corresponding to DE-OS 28 13 941) is described.

Example I.

1 kg of vermiculite mineral from South Africa, known as "Mandoval micron grade", was dissolved in 5 l of saturated sodium chloride solution Refluxed for 30 minutes. Excess saline solution was decanted off, and the Vermiculite was washed in 5 liters of distilled water. Then the vermiculite was five times with I I each washed with distilled water on a Buchner filter funnel. The wet vermicut cake was back in brought to the reflux vessel and for 2 h · -sit 1.2j mol Butylammonium chloride, which had been made up to a volume of 51 with distilled water Refluxed. After refluxing, the vermiculite became again as above described washed, with a rapid expansion of the vermiculite to about the ofache of its original Volume took place. After standing overnight, the supernatant liquid was decanted off. The swollen vermiculite particles (6 l) were divided into two portions of about 3 l each, and each portion was made ^: Make up to 41 mil distilled water to form a suspension in a large beaker.

Each suspension was then mixed for 1 hour with a paddle mixer immersed in the beaker running at 6500 U / mln circulated, stirred. The suspensions became close Maintained ambient temperature by spraying cold water on the outside of the cups. at This RC virus got air into the suspensions of the V'ermiculite lamellae and a foam formed on the surface of each suspension. The depth of the foam gained weight. when the suspensions were allowed to stand for 30 minutes and about 600 ml of foam became each Suspension taken.

The sc'iiiium was placed in a forivi and dried in a well-ventilated oven at 60 ° C. Then, a hard vermiculite foam having a density of 0.08 g / cm ¹ , which conformed to the shape and had a thin film of vermiculite formed on its surface, was taken out of the mold.

The suspensions were again whipped for 60 minutes at high speed and King allowed to stand for a further 30 minutes, after which a fresh amount of foam was kept formed. The procedure was repeated a number of times, forming different batches of foam from the same suspensions. These were combined with one another, transferred to a mold and dried in the oven, forming a solid vermiculite stool with a density of 0.08 g / cm ¹ and a mean diameter of 0.7 mm

Example 2

r'bv "-criTi.itilcn ·: ^ \ errr.uvililiiiiner.il jiii \ nr; l- '/: ni iui; Nu · 1ι' Auri !:.""min l.iru! in ei :: e ' ·! ■■ .ilriuni / iloniliovjne unier ΚίκκΙΚιί 'and washed thoroughly several times with distilled water. Then the vermiculite particles were refluxed for 2 hours in an aqueous solution of n-butylammonium chloride and then again thoroughly washed with distilled water Second washing (which may suitably take a few minutes to a few hours) resulted in a strong swelling of the vermiculite particles to about 6 times their original wet volume.

From the aqueous suspension of swollen vermiculite particles obtained in this way, sufficient water was filtered off until the weight ratio was about 10 ". vermiculite solid to 90% of water. The suspension was placed in a high-shear mixer (Greaves Limited), which had a blade capable of revolving at 6500 rpm, and the suspension was mechanically passed or macerated for 10 minutes by blowing air into the suspension, after which the blade was stopped rotating and the suspension was allowed to stand for 5 minutes there was a foam 25 mm deep above the suspension. The foam was removed with a knife and spread on a switch. The tray containing the foam was placed in a well-ventilated oven at 60 ^° C., and this was done Water was removed by evaporation, if necessary with the aid of a fan or extractor in the oven .. The dry foam could be solidified r Vermiculite foam with a cellular structure that has a density below

so 0.1 g / cm 'and a mean cell diameter of 0.5 mm had to be removed from the shell.

Example 3

A sample of vermiculite (Zonolite No. 4) was like

^J 5 described in Example 2, but the suspension was stirred for 60 minutes in the mixer. The density of the vermiculite foam obtained was 0.035 g / cm ^J and the mean cell diameter was 0.5 mm.

B e i s ρ i e I 4

Vermiculite from South Africa was prepared as described in Example 1 to form an aqueous suspension treated by swollen vermiculite particles. After the solids content of this suspension has been adjusted to 20% by weight the suspension was stirred until it was homogeneous, and once through a »Reior-in-Statom-Mill, which revolved at a speed of 20,000 rpm. Before the suspension into the The shear zone of the mill was guided, air was drawn into the suspension at a rate of 10 l / min measured. The entire suspension was converted into a thick foam. who is left standing overnight in a lower, liquid layer containing some of the larger vermiculite particles and another

"Layer of wet vermiculite foam separated. The Foam (which was stable for a few weeks when wet) was removed and placed in a wire mesh form dried in a well-ventilated oven at 80 ° C. A vermiculite foam board was obtained

^b0 (30.5 cm χ 30.5 c η χ 5.1 cm) with the following properties:

density

Corn pressure resistant wedge

Thermal

I a.!. Ii!:, Eii
\ nte '^; ier

i!: m! ;; i! "iS-jnen / hurry

0.22 g / cm "
0.11 MNm

'l.'lf.i. U ν

Middle
/ elUlurchniesscr

1.5 πι m

Hc i spie I

3 Ky of American vermiculite were made as in example 2 heschrieheii with the formation of swollen Vemiiculllleilchen acts.

I) Ic swollen Vermieuliitcilchen were then in '» • \ ntelle shared, each of which for -45 min in one (Ireaves-Mill was mixed to suspend of diluted vermiculilla cells. Then the '' portions were merged together, and tlie g rolling vermieuliitcilchen were separated, by passing the suspension through a 50 µm sieve. The classified suspension obtained in this way, which has a solids content of about 5 Ciew.-Λ, consider, was on one large gel / ten shell evaporated to its Fesisloff content increase to 2ΓΚ / u Then was made using Dahel beat air into the thick suspension of a kitchen mixer using the blow gun the volume increased to about double. and a wet foam was formed from the whole suspension Small bubble size The foam was spread out on a heated dish and dried overnight, receiving a plate (18th um χ 122 cm 6.4 mm) became. The dry curling foam had the following properties:

density

Compression resistance
Thermal
conductivity
part of the

closed / rush
Middle
/ ell diameter

0.12 g / cm '0.30 MNm -'

0.060 Wm 'K'

41 ",

0.2 mm

H e i s ρ i e I 6

3 kg of South African vermiculite were produced as described in Example I with the formation of swollen vermiculite particles treated.

Then the supernatant water was decanted off. and the swollen vermiculil particles were mixed in 750 ml portions for 10 minutes in a household liquefier. The thick, but pourable suspension had a Feststoffgehall of 20 wt ¹ V. It was foamed one lljushaltsmischgerätes using as described in Example 5. FIG. The foam was then dried in an oven at 90 ° C overnight. being plates

(6! .0 cm ■ <30.5 cm * 6.4 mm) were obtained. Some Panels were stacked using wet foam. and it became a thicker one Plate (30.5 cm -: 30.5 cm χ 3.8 cm) formed and in one Kiln dried The physical properties of the thicker plate are considered below:

density

Koni pression test ig wedge

Thermal

conductivity

part of the

closed cells

Miners

Cell diameter

0.07 g / cm ^: 0.05 MNm

0.048 Wm

ft--.

¹ year? mm

cht g.-jhäumie suspension of anicnkanirrnicu ;: '. -.20 wt. -'- Fe5i «; ofhäeruk) became produced as described in Example 5 In this I all the suspension was not aerated. Reduce in an oven at 140 ° C for 3 hours. being by rapid The development of water vapor as a dry vermiculite '· Schaunistoll with a density of 0.10 g / cm' w unie.

Example X

170 μ of a paste-like suspension of sun south african "sham vermiculite, which was produced as described in Example 5 and had a solid lollipop content of 13 (iew - had been set.) Were placed in an aerosol container that could be pressurized." Fin mixture of 18 g Dichlordlfluormethan and 12 l · Dii> chlorlelralluoräthan was introduced under pressure into the aerosol container and mixed with the Vermiculltsuspension a wet foam was placed on a tray by pressing the Ausstolldüse of the aerosol container, and 24 dried in the air, the so hr -. ^l) The Vermiculltschaumsloff formed had a very fine pore size (mean diameter of the bubbles = 350 μml and a density of 0.05 g / cm '.

Example '·)

-> South African vermiculite (»Ntandoval micron just «; I kg) was 10 h with a mixture of 4 l of water. 130g manganese chloride dietrahydrate and 0.25ml concentrated hydrochloric acid, boiled under reflux Product was washed with water and then with

^{made up} to a total volume of 201 in water. Then 75 ml of Iη-hydrochloric acid and 2 1 30 Uges hydrogen peroxide were added, and the mixture was heated to 60 ° C. for 2 hours with stirring, during which the vermiculite dissipated while taking up almost all of the present

^ Liquid wedge expanded. The mixture was then cooled, filtered, washed with water and made up to 10 liters with added fresh water. The suspension thus obtained was divided into 4 equal portions, and each portion was poured into a 5-liter container with a Greaves 115-Series- Mixer (Mark III) mixed for 1 hour with 6500 for 17 minutes. The combined suspensions were then diluted to 16 l with water and classified by means of a sieve with openings of 50 μm.

^4S hold so that 2.9% by weight was obtained (all added water was distilled water.)

So much water became serdampli through the effect of such heat. that the solids content of the suspension to 20 wt .- ¹ '. increased svurde. Then the mixture became

^v 'L'ocooled. and a surfactant suitable prolein ("Nicerol") was used in a concentration <η 10 '·. ι Volume / weight of the solid vermiculite) added; ei7 !. The mixture was whipped into a foam in a kitchen mixer. After drying in a well-ventilated oven at 90 ^° C, the vermiculite foam formed had a density of 0.1 a / cm '.

Example! 10

1 kg of South African vermiculite mineral ssurde in an aqueous solution but 20 wt .-. Lithium chloride refluxed for h. After thorough washing in a Büchner funnel, the original volume of the vermiculite rice rose eight times. The mixture of swollen vermiculite mir.ir.i! and water t! 0% by weight vermiculite mineral)! hi: \ rig wed the bigger lights of vermiculite ·; were ~ ü a 5 ^r ; ι.rr sieve filtered off, and the FesrstoiYgeraii the Suspfnsion was by evaporation

308 111/124

aul 2 "(k'w.- set I in as olv-rfliichenaklives A suitable protein ("Niccrol") was found in a Quantity of 10 VoI- '. foe / open ant the weight ties vermiailils. was added and the mixture was partially whipped in a kitchen mixer to a slice After drying in a fully ventilated diner The verinlilltschaumsioff formed had a Density of 0.1 g / cm '

Example Il

As described in Example 4, it was made from North American Vermiculite a dried Viimkulilschaumstol'f with a mean l'orengrölic of .1.00 mm and a density of 0.01 g / cm 'produced

Example 12

I. A sample of wet foam, produced as described in Example 6, was treated ^{with a l:} \ nt - ■ '..; ius (It ^ mn: issen foam and / u iifi ". from the microcriculite granules beslanil The mixture was dried in an oil at Wl (. The thus obtained \ ermiculitschaumslnll had a density of 0.22 g / cm and a KompressliMislesligkeil of 0.12 MNm '

Example 13

From the Scliaiimsioll illustrated in Example 5 a finite (62 mm ^ 1.15 mm x 4 mm) was cut. It had a density of 0.12 g / cm. This l'lalle was kept in an oil at 1000 ° C. for 10 minutes. After taking it from the oil it was found that the Plate not visible due to the intense heat was warped. (The dimensions were M mm 134 mm 4 mm). The density dropped aiii ' 0.09 g / cm ', and the compression strength was 0.22MNm '.

This shows that the vernier lamella products of the invention or foams are very wilrmclest and can therefore be used as a fire protection / materlal can, as they are a good malleable wedge at low loss have a Koninressionsfestlgkelt.

Claims (8)

Patent claims: 1. Vermiculite lamellar product produced by chemical Exfoliation of vermiculite particles was formed, characterized by a non-brittle Foam made from exfoliated vermiculite particles that expand continuously and practically evenly extend in all dimensions through the volume of the foam formed. 2. Product according to claim!, Characterized in that that the cell structure has a density of not more than 0.5 g / cm '. 3. Product according to claim 2, characterized in that the cell structure has a density of not more than 0.15 g / cm ¹ . 4. A method for producing a vermiculite lamellar product according to any one of the preceding Claims by exfoliation of vermiculite particles in an aqueous, saline suspension. Formation of a shaped body from the slurry of exfoliated Vermiculite particles and drying in a manner known per se, characterized in that a gas is introduced into the resulting suspension of exfoliated vermiculite particles and the liquid Medium is removed from the foam thus formed by evaporation. 5. The method according to claim 4, characterized in that the introduction of gas into the suspension is effected by rapidly stirring the suspension. 6. The method according to claim 5, characterized in that the introduction of gas by beating the entire suspension is caused to form a foam. 7. The method according to claims 4 to 6, characterized in that the suspension prior to entry of gas is classified by separating coarser vermiculite particles. 8. Use of the vermiculilla lamella product according to claims I to 3 as refractory and / or soundproofingcndc layerpiaitc in the construction industry.