DE202011003679U1 - Hydrogel composite for suspension applications - Google Patents

Abstract

Hydrogel composite in the form of a ready-to-use suspension (hydrogel composite suspension) and / or as a suspension concentrate for dilution with water and / or other liquids and / or as a solid mixture for producing a hydrogel composite suspension by mixing with water and / or another liquid, for the introduction / application and / or treatment, particularly but not exclusively, in / of soil and earth structures, preferably for improving and / or increasing their water storage and / or dispensing capacity, preferably in the case of semi-arid and / or arid soil structures and / or serving the water and nutrient supply of crop plants, preferably intended for introduction into the root region of trees and / or shrubs by means of pressure-free and / or pressure application, comprising: a) at least one natural and / or synthetic superabsorbent polymer (SAP), b) at least one mineral aggregate and / or soil additive toff from the group of igneous rocks and / or sedimentary rocks, characterized in that the contained SAP is and / or is designed as a hydrogel and the particle size of the SAP hydrogel particles is not> 5000 μm, preferably <2500 μm and rock particles obtained from an expanded (blown) quartz porphyry glass from the group of igneous rocks, ...

Description

Technical area

The invention includes, with reference to the descriptive and characterizing part of claim 1 and the sub-claims of the invention, a hydrogel composite suspension (HGKS) in the form of a ready-to-use suspension (hydrogel composite suspension) and / or these in the form of a suspension concentrate for dilution Water and / or other liquids present and / or these present as a solid mixture for preparing a Hydrogelkomposit suspension by mixing with water and / or other liquid, for introduction / application and / or treatment in particular but not exclusively, in soil and earth structures , preferably for improving and / or increasing their water storage and / or dispensing capacity, preferably in semi-arid and / or arid soil structures, is provided and / or water and nutrient supply of crops, preferably for introduction by means of pressure-free and / or print application in the W Root area of trees and / or shrubs.

The composition according to the invention comprises at least one natural and / or synthetic superabsorbent polymer (SAP), preferably and inventively formed as hydrogel composite (HGK) and at least one mineral additive and / or soil additive from the group of igneous rocks and / or sedimentary rocks, wherein at least one igneous rock constituent in expanded (expanded) form. Other inorganic and / or organic substances, in particular plant nutrients and / or the growth of plant-promoting substances may be contained and / or added.

State of the art

The state of the art can be demonstrated by emphasizing the scope of soil conditioners and long-term water storage for the agricultural sector, as follows, from the variety of relevant publications and patents and applications. In the cited patents, the desired effect of SAP, hydrogel composites (HGK) and SAP hybrid materials (SHM) in composition and application is disclosed and the substance group of superabsorbent polymers (SAP) and their properties explained in detail, so that in the context of the present invention description, as far as this is not relevant to the teaching of the invention, be waived.

Common to all products and also to the processes is that the SAP, HGK and SHM are present as powders, granules, pellets and / or molded parts and are introduced into the soil in these forms and / or in the root area of plants, such as shrubs and / or trees be applied with pronounced strong root system.

SAP

= Superabsorberpolymer für natürliche und synthetische Polymere, die mit Wasser Hydrogele bilden. Dies sind beispielsweise vernetzte Kalium- und Nartriumsalze der Polyacrylsäure, Copolymere und Propfpolymere der Acrylsäure und die Salze der Copolymerisate auf der Basis von Acrylsäure und Acrylamid und deren Salze, sowie natürliche Hydrogel bildende Polymere und deren Salze auf der Basis nachwachsender Rohstoffe wie beispielsweise Kartoffelstärke und Polysacchariden allgemein. Superabsorber (SAP) können ein Vielfaches ihres Eigengewichts an Wasser absorbieren, wobei sie zu einem Hydrogel aufquellen. Polymerketten, vor allem von Polyacrylsäure, werden durch vereinzelte kovalente Bindungen untereinander verknüpft. Diese leichte Vernetzung ist notwendig, um die Unlöslichkeit des Polymers in Wasser zu gewährleisten.

HG

= Hydrogel. Ein Hydrogel ist ein in Wasser oder in wässrigen Flüssigkeiten gequollenes hydrophiles polymeres Netzwerk. Die Eigenschaften dieser Gele sind abhängig von der Wechselwirkung zwischen Netzwerk und umgebender Flüssigkeit.

HGK

= Hydrogelkomposit. Darunter wird verstanden, feine SAP-Partikel, die in eine hochporöse mineralische Materix eingelagert oder von dieser umhüllt sind, die auch als Träger für die fein gemahlenen Zuschläge, wie z. B. Lava-Urgesteinsmehl, dient. Das SAP ist durch Wasser aktiviert und bereits teilweise zum Hydrogel ausgebildet.

SHM

= SAP-Hybridmaterial ist ein Superabsorberpolymer (SAP) bei dem die meist mineralischen Zuschlagstoffe, wie z. B. Lavamehl, vor der Polymerisation den Monomeren zugegeben werden und bei der Polymerisation in der Polymermatrix fest gebunden oder eingelagert werden. Wasserhaltige SHM-Hydrogele sind überwiegend zähe, schwammartige Massen, die nur sehr schwer zu zerkleinern sind.

The following abbreviations are used in part in the description and also in the patent claims. The term definitions used serve to better understand and delimit the theory of the invention from the known prior art.

SAP

Superabsorbent polymer for natural and synthetic polymers that form hydrogels with water. These are, for example, crosslinked potassium and nartrium salts of polyacrylic acid, copolymers and graft polymers of acrylic acid and the salts of copolymers based on acrylic acid and acrylamide and salts thereof, and natural hydrogel-forming polymers and their salts based on renewable raw materials such as potato starch and polysaccharides generally. Superabsorbents (SAP) can absorb many times their own weight in water, swelling to a hydrogel. Polymer chains, especially of polyacrylic acid, are linked to each other by isolated covalent bonds. This light crosslinking is necessary to ensure the insolubility of the polymer in water.

HG

= Hydrogel. A hydrogel is a hydrophilic polymeric network swollen in water or aqueous liquids. The properties of these gels depend on the interaction between the network and the surrounding fluid.

HGK

= Hydrogel composite. This is understood to mean fine SAP particles that are embedded in or encased in a highly porous mineral Materix, which is also used as a carrier for the finely ground aggregates, such. B. lava rock form, serves. The SAP is activated by water and already partly formed into a hydrogel.

SHM

= SAP hybrid material is a superabsorbent polymer (SAP) in which the most mineral aggregates, such. For example, lava flour, be added to the monomers prior to polymerization and be firmly bound or incorporated in the polymerization in the polymer matrix. Hydrous SHM hydrogels are predominantly tough, sponge-like masses that are very difficult to crush.

In the European patent specification EP 1 399 397 B1 describes the preparation and application of a typical SAP hybrid material, pre-polymerization introduced mineral fillers, and discloses the applications and shaping. These SHM are not available as a suspension or suspensions can not be prepared from them.

In the PCT application WO 002010003399 A1 It is proposed to subsequently bind all inorganic, mineral and also organic solids to SAP and / or to accumulate them and to form the resulting HGK, for example, as granules, pellets, etc., and to introduce them into the soil in this form.

In the German patent no. DE 196 54745 C2 describes the production of porous superabsorbent polymers (SAP) based on renewable raw materials. However, these SAPs have the adverse effect of agglomerating, homogeneous and stable gelation when used in the agricultural field, which causes the plant soil to become silted up and damages the fine roots of the plants and does not provide the plant's roots with the water, minerals and trace elements required for growth Make available. These SAPs are not present as a suspension and no stable HGK suspensions suitable for application in the root area can be produced therefrom.

It is u. a. It is recommended in the literature that the SAP should be subsequently applied to the area of the root system, previously moistened with water and swelled and then introduced into the root area by means of lance applicators. A blending with active ingredients and mineral additives and / or other active ingredients is not possible and ultimately it comes in the introduction in the root area not to a fine distribution of SAP particles, but to a concentrated, punctual gel formation, which is not desirable and also to compaction in which the soil surrounding the root system leads.

invention task

The invention has for its object to find a hydrogel composite (HGK), which is present in the training as a stable aqueous suspension or as a suspension based on another liquid and / or to find a solid mixture of the type HGK, from the addition of water and / or other liquids stable suspensions can be prepared, with which it is preferably possible to introduce by non-pressure application and / or by pressure application SAP particles in combination with, for example, finely ground rock powders and / or other additives and active ingredients.

This suspension, which is used as a hydrogel composite suspension, must ensure that the SAP particles contained therein are already designed as hydrogel but do not form a homogeneous gel, ie are present as individual hydrogel particles, so that these, together with the other Add aggregates and active ingredients very well in the soil, preferably in the root area of shrubs and trees and connect with the surrounding soil, without causing a compaction and / or silting up.

These requirements also apply to entprechende suspension concentrates and / or solid mixtures for the preparation of hydrogel composite suspensions.

Representation and embodiments of the invention

Surprisingly, it has been found with reference to claim 1 that the object according to the invention is achieved in that the hydrogel composite suspension according to the invention and / or solid mixture required for its preparation must contain the SAP as hydrogel particles and the particle size of the hydrogel particles should not> 5000 μm and preferably <2500 μm, and expanded perlite in the form of highly porous, open-cell and irregularly formed particles, obtained by breaking and / or grinding and / or as abrasion and / or as fragments of cell and / or pore walls of expanded pearlite beads, be included.

It has also been found that these pearlite particles must have a particle size <500 microns so that they do not settle in the suspension and prevent SAP hydrogel particles from uniting to form a stable hydrogel mass. In addition, it has been found that minerals and / or minerals contained must have a particle size of <100 μm, so that they do not settle in the suspension but attach to the expanded pearlite particles and / or are held in suspension by them.

According to the teachings of the invention for forming a stable suspension, it is preferred that the particle size d _{50 of} the expanded perlite particles is greater than the particle size d _{50 of} the unexpanded mineral and minerals.

The expanded (expanded) pearlite should be explained as follows: The unexpanded mineral perlite belongs to the group of volcanic rhyolites (igneous rocks) or quartz porphyry glasses. It is a natural glass, which originated from lava and cooled very quickly in contact with water or water vapor and simultaneous strong pressure. Raw Perlite (also known as Perlite) contains on average two to six per cent of water that, when exposed to temperatures greater than 700 ° Celsius, expands due to the explosive evaporation of water in the rock and swells up to twenty times its original volume. Blown perlite has a pore structure with many pores, whose pore walls, so the cell walls, are permeable, porous.

Commercial, puffed perlite has, depending on the shape and starting grain size of the ground crude perlite, an irregular, spherical shape and a particle size between 10 and 6000 microns and a pore volume of about 95 percent by volume.

Thus, when expanded perlite is ground and / or crushed or subjected to mechanical stress under pressure, for example as filter aid, it is in the form of particles in irregularly shaped, highly porous flakes (particles) whose structure can be compared with cellulose fibers. The bulk densities of such pearlite particles, or pearlite flakes, are between 50 and 90 kg / m ³ .

A further advantageous embodiment of the invention is achieved in that hydrophilic, expanded spherical pearlite having a particle size of at least 10 μm and a maximum of 500 μm is added as soil loosening agent and / or active substance carrier,

A further advantageous embodiment of the invention results with reference to claim 8 and 9, that the hydrophilic pearlite beads are filled with liquid active ingredients and / or additives and the surface accessible pore openings by a coating, for example with water glass or by another surface coating, closed are.

This is, with reference to claim 7, ie the possible addition of plant nutrients and / or -strärkungsmittel and / or fertilizers, and / or insecticides and / or pesticides and / or fungicides and / or microorganisms, a further advantageous embodiment of the invention, it allows these active ingredients undissolved in the composition and / or suspension of the invention to suspend, so that they are released only after the application.

A further advantageous embodiment of the invention is achieved in that, instead of the hydrophilic, expanded pearlite beads, synthetic and / or natural polymers, including SAP, are used, which through a porous and open, accessible pore structure also wholly and / or partially with liquid active ingredients and / or or additives may be filled. Such polymers can be loaded with liquids at a multiple of their own weight. Particularly preferred is the use of biodegradable polymers based on renewable raw materials.

The felted polymer particles, preferably with a particle size of <500 μm, can additionally be provided with a coating which seals the pores accessible to the surface.

A further advantageous development of the invention is achieved by containing nonionic and / or anionic and / or cationic surfactants and / or wetting agents. This is preferably for the purpose of improving the wetting and binding capacity of the suspension according to the invention in the soil and for improving the suspension stability.

The suspension carrier used is preferably water, but other carrier liquids may also be used.

embodiments

The various possible embodiments of the invention will become apparent from the disclosed teaching of the invention and the descriptive part of the protective claims 1 to 11.

Invention typical exemplary embodiments are listed in Table 1. The manufacturing technologies are not the subject of the patent application but prior art, so that they are not listed and described. Table 1 Embodiments - Compositions no. no. raw material Characteristics Raw material Proportion% by weight shape annotation 1 Hydrogel particle HG SAP-potassium-polyacrylate particle size d ₅₀ : 1000 μm 10 suspension medium viscosity, stable perlite Perlite particles blown particle size d ₅₀ : 150 μ 10 Lavender flour, fine Particle size d ₅₀ : 30 μm 10 water the. 70 2 Hydrogel particle HG SAP-potassium-polyacrylate particle size d ₅₀ : 1200 μm 40 Solid mixture, finely dispersed Suspension production perlite Perlite particles blown particle size d ₅₀ : 150 μ 20 Lavender flour, fine Particle size d ₅₀ : 30 μm 20 water the. 20 3 Hydrogel particle HG SAP-potassium-polyacrylate particle size d ₅₀ : 850 μm 10 suspension medium viscosity, stable Perlite (particles) Perlite particles blown, particle size d ₅₀ : 150 μm 10 Pearlite (pearls) Spherical, inflated particle size d ₅₀ : 80 μm 2.5 Lavender flour, fine Particle size d ₅₀ : 30 μm, 10 water the. 67.5

It has been found to be particularly advantageous that the combination of expanded perlite particles and expanded pearlite beads substantially improves the suspension stability and the flow behavior of the hydrogel-composite suspensions according to the invention.

This also applies to the combination of the expanded perlite particles with corresponding highly porous and thus absorbent polymer particles.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 1399397 B1 [0006]
• WO 002010003399 A1 [0007]
• DE 19654745 C2 [0008]

Claims (12)

Hydrogel composite in the form of a ready-to-use suspension (hydrogel composite suspension) and / or as a suspension concentrate for dilution with water and / or other liquids and / or as a solid mixture for producing a hydrogel composite suspension by mixing with water and / or another liquid, for introduction / application and / or treatment, in particular but not limited to, in soil and earth structures, preferably for improving and / or increasing their water retention and / or release capacity, preferably in semi-arid and / or arid soil structures and / or or the water and nutrient supply of crop plants, preferably intended for introduction by means of pressure-free and / or pressure application into the root area of trees and / or shrubs, containing: a) at least one natural and / or synthetic superabsorbent polymer (SAP), b) at least one mineral aggregate and / or soil aid Toff from the group of igneous rocks and / or sedimentary rocks, characterized in that the SAP contained is formed as a hydrogel and / or and the particle size of the SAP hydrogel particles is not> 5000 .mu.m, preferably <2500 .mu.m and rock particles, won from an expanded (expanded) quartz porphyry glass from the group of igneous rocks. According to claim 1, characterized in that the expanded rock particles are natural and / or industrially expanded perlite particles. After one or more of the preceding claims, characterized in that the expanded perlite particles in the form of highly porous, open-cell and irregularly formed particles obtained by breaking and / or grinding and / or as abrasion and / or as fragments of the cell walls and / or pore walls of expanded Perlite beads (pearlite beads) are present. After one or more of the preceding claims, characterized in that the expanded perlite particles have a particle size <500 microns. According to one or more of the preceding claims, characterized in that expanded, hydrophilic spherical pearlite (pearlite beads) having a particle size d ₅₀ of at least 10 microns and a maximum of 500 microns is included. According to one or more of the preceding claims, characterized in that highly porous, open-pored natural and / or synthetic polymer particles are contained whose particle size is not> 5000 microns and they can also identify superabsorber properties. After one or more of the preceding claims, characterized in that the minerals and / or minerals contained have a particle size <100 microns. According to one or more of the preceding claims, characterized in that plant nutrients and / or -stärkungsmittel and / or fertilizers and / or insecticides and / or pesticides and / or bactericides and / or fungicides and / or microorganisms are contained. According to one or more of the preceding claims, characterized in that the pores of the expanded, spherical perlite and / or the highly porous, open-pore polymer particles are filled with liquid active ingredients and / or additives. According to one or more of the preceding claims, characterized in that the open pore entrances to the surface of the expanded, spherical perlite and / or the highly porous, open-pore polymer particles are closed by an applied coating (surface coating). According to one or more of the preceding claims, characterized in that the particle size d _{50 of} the unexpanded mineral and / or minerals is smaller than the particle size d _{50 of} the expanded perlite particles. According to one or more of the preceding claims, characterized in that nonionic and / or anionic and / or cationic surfactants and / or wetting agents are contained.