DE2828972A1 - METHOD FOR FASTENING A LOOSE, GRAINY OR POWDERED MATERIAL - Google Patents

Description

Andrejewski, Honke, Gesthuysen & Masch patent attorneys

if Physicist

J Dr. Waiter Andreevsky

Graduate engineer Dr.-lng. Manfred Honke Graduate engineer Hans Dieter Gesthuysen Graduate physicist Dr. Karl Gerhard Masch

Lawyer files: 43 Essen 1, Theaterplatz3, Postf 789

32 Iij2. 13-th 2b. June I97B

Patent application

REVERTEX (SOUTH AFRICA)
(PROPRIETARY) LIMITED

44B Lansdowne Road

Jacobs, Natal 'South Africa

Method of grouting a loose, granular or powdery material.

The invention relates to a method for grouting a loose, granular or powdery material, i.e. for production a coherent mass of granular or powdery material, for example sand, which essentially consists of individual particles or small clusters of particles, or of a soil, which in general has a low clay content, or from coal dust, wood flour, minerals and the like.

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Andrejewski, Honke, Gesthuysen & Masch, patent attorneys

2428972

in food

Such a multi-particle material as for example sand in most cases has poor natural packing properties, so that such a material in particular in the dry state does not withstand an adequate load and, · or tends to a low filling density, so that it through Air movements can be blown away very easily.

To give such a fine-grained material the desired load-bearing capacity to lend, is already in practice, for example in the production of base courses in road construction, the available material with lime, cement, hot bitumen, synthetic aqueous polymeric emulsions or others Mixed products, known by every road builder Process in which compaction is usually carried out with heavy rollers.

In the production of base courses for road construction is mostly lime is used, but in certain cases it cannot be used if other substances are taken into account have to. Mixtures with cement additives result in an end product which tends to become brittle or too brittle under stress cracks or cracks when setting due to shrinkage, while bitumen-like products are processed hot must be, which is not always safe, but at least cumbersome and expensive. With the ones used so far Synthetic polymeric emulsions have the problem that they have excellent compressive strength in the dry state and bearing capacity, but these properties are noticeably impaired when the base layer of a road with Water becomes saturated.

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Andrejewski, Honke, Gesfhuysen & Masch, patent attorneys in Essen

-y-i

In other applications where polymeric emulsions have been used to create loosely unrelated material Mass production, such as in the production of coal briquettes, lose these briquettes when saturated again essentially their mechanical properties and strength.

The invention has therefore set itself the task of providing a method for grouting a loose, granular or powdery To realize material in which the water-based polymer emulsion previously used as an additive is modified in this way becomes that with a grouting of a loose, granular or powdery material, depending on requirements, more or less large coherent mixed eggs can be produced which retain their mechanical properties even after long soaking.

Insofar as in the context of the description the term "polymeric emulsion" is used, it has the usual commercial meaning, although it is more of a polymeric dispersion acts.

A method for grouting according to the invention is identified a loose, granular or powdery material, in which this material has a polymer emulsion in such a Amount is added that results in a cohesive mass, essentially in that as a polymeric emulsion a emulsion stabilized with a dispersant is used during the polymerization.

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Andrejewski, Honke, Gesthuysen & Masch, patent attorneys in Essen

This dispersant is added to the material either alone or in a mixture with synthetic or natural polymeric emulsions, Solutions or suspensions added. A lower alkylnaphthalene sulfonic acid salt is preferably used as the dispersant, including alkylidene bis (naphthalene sulphonic acid) salts such as methylene bis (naphthalene sulphonic acid) salts, and the sodium salt of polymerized alkyl naphthalene sulfonic acid added.

The term "Dispergens" is used here in the normally commercially available Meaning used, which is a special type of the genus known as "stabilizers", the other types of which are known as "surfactants" and "colloid stabilizers". So far known the use of "dispersants" in emulsion polymerization is not considered by those skilled in the art, namely because of the low rates of polymerization with sparingly soluble polymers, the end product usually being gritty or gritty and is therefore useless for the usual applications.

The dry weight of the polymer or polymers as a percentage of the granular or dusty material can be between $ 0.1 and $ 15, but ideally should not exceed $ 5 and typically be $ 0.5 - $ 2.0.

The emulsion can be added to the material diluted or undiluted, depending on the desired penetration, or it can be added with mechanically mixed with the material. After such a treatment and before or after complete or partial treatment

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Andrejewski, Honke, Gesthuysen & Masch, patent attorneys in Essen

drying, the material can be compacted according to the specific application. The aqueous Additions to polymeric emulsions contain homopolymers and copolymers of the following monomers:

a) vinyl ester of an aliphatic acid with 1-18 carbon atoms, in particular vinyl acetate, vinyl propionate and vinyl "Versatat" (a trademark of Shell);

b) Acrylic and methacrylic acid esters of an alcohol with 1-1δ C atoms, in particular methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate and methyl methacrylate;

c) Mono- and diethylenically unsaturated hydrocarbons such as styrene and aliphatic dienes such as Butadienes;

d) Unsaturated carboxylic acids such as acrylic acid, methacrylic acid, Crotonic acid, fumaronic acid and itaconic acid;

e) Unsaturated liarboxyl esters of an alcohol with another functional group such as G-lycidil methacrylate, Hydroxyethyl acrylate and hydroxypropyl acrylate;

f) vinyl monomers such as acrylamide, acrylonitrile, Methylolacrylamide and methacrylamide.

As optimal properties in the particular application, the monomers should be combined in such a way that they make up the end product

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Andrejewski, Honke, Gesthuysen & Masch, patent attorneys in Essen

give maximum water resistance, along with the required dispersion properties such as stability, particle size, Surface tension and minimum film formation temperature.

The initiation of the polymerization can be carried out by any free radical-forming method, either thermally or chemically initiated. There is preferably the initiator system from ammonium or potassium persulphate (supersulphuric potassium) in combination with hydrogen peroxide and for the purpose Achieving a reasonable rate of reaction and good final conversion.

Other ingredients in the emulsion are molecular weight modifiers (Chain transfer agents), electrolytes, salts, plasticizers, solvents, smaller amounts of auxiliary stabilizers (Colloid or surfactant type) and similar substances used in the field of emulsion polymerization are known, as long as these agents do not degrade the desired final dispersion properties.

In addition, water-soluble substances including certain herbicides, insecticides, fertilizers and the like. The polymer emulsion or the masses produced are added directly. By choosing suitable grains or powders Material and water-soluble material can be made into pellets or other forms for agricultural use. For example, a briquette of sawdust with such a water-soluble substance as an internal therapeutic plant protection product and ,, or a fertilizer and / or a fungicide or the like. Produce.

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Andrejewski, Honke, Gesthuysen & Masch, patent attorneys in Essen

The reaction temperatures for the polymerization are in Range between 5 ° C and 95 ° C, preferably between 70 ° C and 90 ° c.

A few examples are intended to explain the invention further below, with the amounts - unless otherwise stated are given in "parts by weight".

example 1

A reactor with a stirrer, a dropping funnel, reflux condenser and thermometer were loaded with:

Water 37.92

"Daxad 15" * 1.87

Crotonic acid 0.93

The reactor was heated to 70 C and charged with:

Styrene 2.57) initial

Butyl acrylate I ₃ 87) monomer

Methyl methacrylate 0.14) batch

Water 0.93

Ammonium perulfate 0.06

50% hydrogen peroxide 0.04

* "Daxad 15" is the trademark of W.R. Grace.

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Andrejewski, Honke, Gesthuysen & Masch, patent attorneys in Essen

The reactor was then heated to 90 ° C. and the stirrer at this' temperature switched on for 30 minutes. After that it was within The following mixture is continuously fed into the reactor over a period of 3 hours:

Styrene 23.11)

Butyl acrylate l6.8l) monomer

Methyl methacrylate 1.26) batch.

At the same time, the following mixture was added dropwise over a period of 3 h 15 min:

water 9.34 Ammonium perulfate 0.15 50 ^ hydrogen super peroxide 0.09 "Daxad 15" 1.87

After all the additives were added, the temperature of the batch was held at 90 ° C. for 60 minutes and then cooled. During cooling, the following was added at 70 ^° C.:

Tertiarbutyl hydroperoxide Ο, Οβ and at 35 ° C a mixture of:

Water 0.93

Sodium metabisulfate 0.05.

Andrejewski, Honke, Gesthuysen & Masch, patent attorneys

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The final emulsion contained approximately $ 50 solids. before When used, the emulsion was sieved and the pH was adjusted as usual.

Example 2

The procedure was the same as in Example 1, but the monomeric charge (initial plus delayed) contained:

Methyl methacrylate 27.08

Butyl acrylate 18.68.

Example 3

The procedure was the same as in Example 1, but the monomeric charge (initial plus delayed) contained:

Vinyl acetate 30.35

Butyl acrylate 15 , cl .

example K

In mixtures almost the same as those of Examples 1, 2 and was used instead of butyl acrylate

2-ethylhexyl acrylate
used.

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ORIGINAL INSPECTED

Andrejewski, Honke, Gesthuysen & Masch, patent attorneys in Essen Example 5

Corresponded to Example 1, but a chain transfer agent was added to the delayed monomeric mixture, namely

Carbon tetrachloride 0.0; 5.

(Such chain transfer agents can optionally also be used in the other compositions.)

Example 6

A pressure reactor with a stirrer was charged with

Demineralised water 52.01 "Daxad 15" 0.87 Latex breeding 3.46 Tertiary dodecyl mercaptan 0.22 Acrylic acid 0.87 Ammonium persulfate 0.09.

The reactor was then sparged with nitrogen and charged with:

Butadiene 10.8; 5

Styrene β, Οβ

Acrylonitrile 8.66.

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Andrejewski, Honice, Gesthuysen & Masch, patent attorneys in Essen

The batch was heated to 55 ° C and held at that temperature for 2 hours held.

It was then increased to 65 ° C. and the following monomeric mixture added within a period of J5 h:

Butadiene 10.83

Styrene β, Οβ.

After polymerization of $ 70 of the total monomer Batch was

Ammonium persulfate 0.04

added to the reaction charge.

The batch was kept at 65 ^° C. until the conversion to $ 95 was reached.

Residual monomer was removed by steam distillation, the Material sifted, concentrated and its pH if necessary set.

The latex cultivation mentioned was one with a surface treating agent stabilized, carboxylated styrene-butadiene polymer emulsion with a part size of approximately 0.10 microns.

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Andrejewski, Honke, Gesthuysen & Masch, patent attorneys in Essen Example 7

The emulsions prepared in the previous examples were used during or after the polymerization for the purpose of reduction a plasticizer or a coalescing solvent is added to the film-forming temperature.

For example, after the preparation of the emulsion prepared in Example 1, a coalescing solvent was slowly added with stirring added:

Emulsion coalescence - minimum film formation

solvent temperature after 2 hours

According to example 1 0% "Dalpad A" 2 V ³ C

¹¹ "1 IJg" Dalpad A "19 ° C

¹¹ "1 2 $ " Dalpad A "13.5 ° C

"" 1 k <fo "Dalpad A"

Example 8

As in Example 1, but the monomer batch (initial and delayed batch) contained:

Styrene 19.98 Butyl acrylate 23.34 Methyl methacrylate 1.50 Glycidyl methacrylate * 0.94

Glycidyl methacrylate became the one with the delayed monomer charge added.

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Andrejewski, Honke, Gesthuysen & Masch, patent attorneys in Essen

The product was made with. Ammonia to a pH of about 9.0 set.

Example 9

As in Example 8, but the monomer charge (initial plus delayed charge) contained:

Styrene 22.88

2-ethylhexalacrylate 19.63

Methyl methacrylate 2.32

Glycidyl methacrylate 0.93.

Example 10

Corresponded to Example 1, but contained the monomer charge (Initial plus delayed batch):

Styrene 22.88

2-ethylhexyl acrylate 20, 54 Methyl methacrylate 2.34.

The various emulsions prepared in this way were then tested as follows:

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Andrejewski, Honke, Gesthuysen & Masch, patent attorneys in Essen Example 8

To improve the strength of sand masses temporarily under water, the prepared according to Example 1, copolymeric emulsion stabilized with a styrene-butadiene acrylate dispersant, diluted to 6.25% pesticides and with dry Sea sand mixed as follows:

Sand 100

Diluted emulsion 8.

The mixture contained - based on sand (level on sand) - $ 0.5 in dry polymer and $ 8 in water.

For unlimited compressive strength measurements, the sand mixture was compacted in cylindrical shapes 90 mm high and 45 mm 0, then dried through, the resulting body removed from the mold and pressurized.

A natural rubber-stabilized polyvinyl acetate homopolymer was used as a control Emulsion or a styrene butyl acrylate copolymer emulsion stabilized with a surface treatment agent added, for all three differently stabilized emulsions in the same way and with each of the the same amount has been used.

The following results were obtained:

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Andrejewski, Honke, Gesthuysen & Masch, patent attorneys in Essen

Unlimited compressive strengths (kPa)

Dry After After rehearsals 4 hours 4 days Watering watering

Dispersant-stabilized Copolymer emulsion

Rubber-stabilized homopolymer emulsion

Surfactant-stabilized copolymer emulsion

1676 593 290 965 26th 0 154 36 0

The one grouted with the dispersant-stabilized copolymer emulsion (aggregated) sand had a significantly higher compressive strength after irrigation than one stabilized with natural rubber Polymer emulsion grouted sand and one stabilized with a surface treatment agent Polymer emulsion grouted sand.

To determine the strength of the application of base courses In road construction, various types of soil were mortared with the dispersant-stabilized copolymer emulsions and according to the California Bearing Ratio (CBR) tested. There was a significant improvement after irrigation compared to control mixtures, which were compacted in the usual way, in particular with normally unsuitable material and with

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Andrejewski, Honke, Gesthuysen & Masch, patent attorneys in Essen

lower compression. This gives the opportunity to To use on-site material normally used for the application in civil engineering is unsuitable. Just the tests CBR cores were stored under water for four days beforehand, with the polymer at $ 0.5 solids based on the used Earth was used.

a) Soil normally unusable for base courses in road construction (because of the high plasticity index):

CBR value With $ 0.5 polymer compression control 49
29
22nd 100
96
90 24
21
6th

b) Usually useful for base courses in road construction Earth:

CBR value

Compaction ($) control with 0.5 $ polymer

100 58 58

96 40 58

90 40 43

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Andrejewski, Honke, Gesthuysen & Masch, patent attorneys in Essen Example 9

For most uses, lumpy charcoal is charcoal powder preferable. When using binders such as starch, molasses and polyvinyl acetate, the moldings must be dry are held because under the pressure of moldings piled up over them, their shape when they get wet in the rain lose and collapse.

Charcoal powder was mixed with a dilute emulsion as follows:

Charcoal 196.0 g

Emulsion (Example 1) J>, 6 g) first

Pre-mix water 108.4).

The wet mixture was applied at a pressure of about 3 kgf / mm (2 tons / square inch) into cylindrical briquettes with a diameter of 50 mm condensed. The briquettes were then dried and subjected to unlimited compressive strength tests before and after immersion in water.

An externally plasticized polyvinyl acetate homopolymer was used as a control additive, which was stabilized with natural rubber, also an Ij5 # starch solution and finally a styrene butadiene selected. The unlimited pressure tests before and after immersion in water gave the following results:

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Andrejewski, Honke, Gesthuysen & Masch, patent attorneys in Essen

Unlimited Compressive strength kp / cm Dry
Test items After going into hiding
in water (1 h) Dispersant stabilized
Copolymer 37.7 35.1 Rubber stabilized
PVAc homopolymer 36.9 25.9 strength 45 0 Dispersant stabilized
Styrene butadiene 36 35.6

The emulsions stabilized with the dispersant were grouted or mixed charcoal had a much greater compressive strength than the other briquettes after irrigation.

In the same way as charcoal, minerals such as coal, chrome, vanadium, etc. can also be briquetted. Chrome briquettes 4x5x1 gin with a 0.6 ^ -igen dry dispersant-stabilized Copolymer withstood a pressure of 48 kgf / cm when dry before breaking and after soaking for 1 hour

a pressure of 4o kp / cm, while in the same way stronger

bonded briquettes strengths of 42 kp / cm in dry feed

2
Stand, but showed 0 kp / cm after irrigation.

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Andrejewski, Honke, Gesthuysen & Masch, patent attorneys in Essen Example 10

If a stabilization of layers is required in order to achieve water resistance and at the same time a consolidation against wind and water erosion in the case of embankments or embankments, the dispersant-stabilized systems resulted in a much more effective water protection than rubber-stabilized PVÄc homopolymer emulsions. Lumps of Ilinit powder were sprayed with the dispersant-stabilized styrene-BA copolymer and a PVAc emulsion diluted to 1.0% solids in an amount of 5 l / m. After the sprayed emulsions had dried and the fill had been exposed to rain, measurements of the moisture content of the powder under the fill sprayed with the first emulsion gave a value of 1%, while the fill under the PVAc emulsion had a moisture content of 6% .

Example 11

A controlled release of soluble substances such as fertilizers can be achieved by mixing the substances with fine-grained or powdery material such as wood flour and the like. Achieve this mixture with dispersant stabilized Copolymers are grouted and made from them moldings or by adding the soluble substances in the diluted Copolymer are dissolved and then this solution is mixed with the granular or dusty material and taken out this mixture is then used to produce moldings. Dispersant

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Andrejewski, Honke, Gesthuysen & Masch, patent attorneys in Essen

stabilized emulsions give both the desired bond strength as well as a certain water resistance.

Wood flour bound with dispersant-stabilized copolymer copolymer water resistance

2.6 3 min

2.0 2 min ^ O see

1.0 1 min 10 sec

0.5 45 sec

0.0 5 sec

5.0 strength 5 sec

Example 12

In many areas the construction of structures is hampered by the great distances from which the building materials are brought in especially cement products and bricks. By using the soil available on site, especially sandy soil, and a dispersant-stabilized one Copolymer emulsion, bricks, blocks, wall panels and the like can be produced, which not only in the dry state are solid, but are also useful when exposed to humid climates or rain. This is how blocks were made by 120 kg of sand with a low ($ 5) clay content and 9.3 kg of a dispersant-stabilized diluted to $ 9.7 of pesticides

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Andrejewski, Honke, Gesthuysen & Masch, patent attorneys in Essen

Copolymer emulsion were mixed. To determine the strength and water resistance and mixtures of sand and varying amounts of copolymer emulsions have been used Made of sea sand sample cubes measuring 45 x 90 mm and then tested in a dry state and after various storage under water. It was used as a control an identical cube of sand with a rubber-stabilized PVAc homopolymer emulsion sourced with a pesticide content of $ 0.5 also tested on the sand.

Dispersant Unlimited compressive strength kPa 4 days
under water stabilized 4 h
under water 193 Copolymer
(*) Dry
Test items 309 446 0.5 1173 745 825 1.0 2482 1427 1031 i, 5 3965 1732 0 2.0 4552 26th Rubber stabilized
PVAc homopolymer
(0.5) 965

Substances grouted with dispersant-stabilized copolymer showed especially after storage under water against rubber stabilized PVAc homopolymer higher strength.

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Andrejewski, Honke, Gesthuysen & Masch, patent attorneys in Essen

It is noteworthy that the emulsions of the present invention are large in size Have surface tensions, with the addition of dispersants hardly affects the surface tension of the water. It is also noteworthy that the emulsions according to the invention one encompass a wide range of particle sizes, which is very unusual.

The surprising feature of the invention is that the unusual measure of using a dispersing agent in an emulsion polymerization, which is considered impractical by those skilled in the art because of the expected formation of a high percentage of grit or gravel and because of discoloration, leads to a product which not only does it not migrate during drying (and can therefore be used to grout sand to a considerable depth of more than 3 ^cm ), but it also results in a watertight coherent mass.

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Claims (6)

2828372 Andrejewski, Honke, Gesthuysen & Masch, patent attorneys in Essen Patent claims: 1. Method for producing a coherent mass granular or powdery material, which also when moistened retains its mechanical properties, in which the granular or powdery material is a polymeric emulsion in such an amount is added that a coherent Mass results, characterized in that that an emulsion stabilized with a dispersant during the polymerization is used as the polymeric emulsion will. 2. The method according to claim 1, characterized in that the dispersant is selected from the group which is a lower one Alkyl naphthalene sulfonic acid salt, a lower alkylidene bis- (naphthalene sulfonic acid) Contains the salt and the sodium salt of a polymeric alkyl naphthalene sulfonic acid. 3 · Method according to claim 1 or 2, characterized in that the polymeric emulsions are made from one or more of the following monomers: a) vinyl ester of an aliphatic acid with 1-18 carbon atoms, especially vinyl acetate, vinyl propionate and vinyl "Versatat" (Viarenzeichen of the Shell company); b) Acrylic and methacrylic acid esters of an alcohol with 1-18 C atoms, in particular methyl acrylate, fithyl acrylate, butyl acrylate, 2-ethylhexyl acrylate and methyl methacrylate; 809883/0925 ORIGINAL INSPECTED Andrejewski, Honke, Gesthuysen & Masch, patent attorneys in Essen c) Mono- and diethylenically unsaturated hydrocarbons such as styrene and aliphatic ^ dienes such as butadienes; d) Unsaturated carboxylic acids such as acrylic acid, methacrylic acid, Crotonic acid, fumaronic acid and itaconic acid; e) Unsaturated carboxyl esters of an alcohol with a further functional group such as glycidyl methacrylate, hydroxethyl acrylate and hydroxypropyl acrylate; f) vinyl monomers such as acrylamide, acrylonitrile, methylol-acrylamide and methacrylamide, the polymeric emulsion being stabilized with a dispersant and added in an amount such that the dry weight of the polymer as a proportion of the granular or powdery material is between 0.1 and 15 $. 4. The method according to any one of claims 1 to j5, characterized in that the polymer emulsion is added in such an amount that the dry weight of the polymer as a proportion of the granular or powdery material between 0.1 and 15%, preferably between 0.1 and $ 5 and more particularly between 0.5 and 2% . 5. The method according to any one of claims 1 to 4, characterized in that that the polymeric emulsion is applied to a sand surface in such an amount that the sand is up to one noticeable depth is saturated and thereby mortared. 109883/0921 Andrejewski, Honke, Gesthuysen & Masch, patent attorneys in Essen 6. The method according to any one of claims 1 to 5> characterized in that further synthetic or natural polymeric emulsions, solutions or suspensions are added to the granular or powdery material. 7. Method according to one of Claims 1 to 6, characterized in that a water-soluble, agriculturally useful substance is added to the granular or powdery material. 809883/0925