WO1996036653A2 - Water-resistant barrier material - Google Patents

Abstract

A new type of water-resistant barrier material is proposed. The barrier material in question is intended for use in particular for finishing, forming or building up protective, adhesive and intermediate layers or films or in the production of unsupported films with excellent barrier characteristics against gaseous and/or liquid ambient media, in particular oxygen, air, water vapour and the like. Even a single layer of the proposed material has extremely low oxygen- and water-permeability values.

Description

 Water resistant barrier material

The invention relates to a water-resistant barrier material, which in particular for finishing, forming or building protective, adhesive and intermediate layers or films or for producing carrier-free films with excellent barrier properties against gaseous and / or liquid ambient media, in particular oxygen, air , Water vapor and the like.

The main areas of application for the flat substrates and moldings equipped or coated with them or for the strapless films include in the fields of

- the flat, possibly flexible packaging substrate for food and pharmaceutical products,

- Vehicle construction, aviation and shipbuilding

- construction

- Paint and paint sector given. The barrier material according to the invention can be used to equip or coat both flat substrates and moldings made of metal, plastic, cellulose material and / or inorganic materials, and also to bond them. The equipping of flat substrates, the coating of shaped bodies with or the formation of barrier layers when building up composite materials or laminates by gluing is a known and material-related necessity in the art, so that objects are protected against environmental influences and the service life is extended. Protection against environmental influences has a high priority in the national economy. When it comes to packaging, especially for the food and pharmaceutical sectors, but also for other high-quality goods, particularly high demands are placed on the barrier equipment. In the case of fillings from the food and pharmaceutical sectors in particular, the barrier materials must be chemically and physically inert and must not release any toxic, taste and odor-influencing substances or experience sensory changes through them. Furthermore, they may not trigger so-called "scalping" effects in direct or indirect product contacts. In order to be able to achieve this goal with good barrier properties, in particular with respect to oxygen and / or water vapor, with agents according to the state of the art, solvent, water and / or monomer-containing barrier materials, such as coating compositions, lacquer, must predominantly be used. In these product groups, the solvents are important auxiliaries, for example to obtain barrier materials in solid, processable aggregate states from solid polymers and / or resins in order to be able to wet the material surfaces to be coated in order to develop adhesion.

The solvents required for this, provided they are not water or monomers (reactive diluents), are aliphatic and aromatic, such as esters, ketones, toluene, xylene and the like, and must be removed from the barrier materials after use. The released solvents must be disposed of or recycled using costly techniques in accordance with emissions legislation and TA-Luft. In the case of the so-called "aqueous" barrier materials, up to 20% of organic solvents are added to the solvent "water", which, after removal, must also be disposed of according to the TA-Luft.

One of the greatest disadvantages when using solvent-containing polymer and resin solutions as a barrier material is that the solvent has to be removed by evaporation to form barrier layers. The evaporation or expulsion of the solvents takes place almost exclusively via the pores that form. Since these pores are also responsible for the permeability to oxygen and water vapor, in practice several barrier layers must be placed on top of one another in order to achieve good barrier properties. Such a process technology alone to achieve low-pore or low-pore barrier layers is therefore extremely cost-intensive.

Solvent-free coating or barrier compositions have also become known in recent times. Instead of inert solvents, such compositions contain so-called reactive diluents or monomers, which integrate into the polymer matrix during curing or crosslinking. Since these are relatively low molecular weight compounds, they are not only physiologically questionable, but also have characteristic, intense, negative taste and smell notes. The one that can be achieved

The degree of crosslinking is often only ≤ 90%, so that they are not suitable, among other things, for equipping packaging materials for food and pharmaceuticals. However, too low a degree of networking can also lead to problems in technical areas, especially in terms of resistance to environmental influences. Overall, the reactive thinners have the disadvantage that if residues thereof, even in the ppm range, are not crosslinked, they adversely affect the adhesion (adhesion) at the interface, because they can stray like inert solvents. In order to accelerate the polymerization or hardening at high production speeds, polymerizable barrier materials that can be hardened by means of ionizing rays, in particular electron beams and UV rays, have also been known for several years.

Photoinitiators and possibly so-called synergists are added to the UV-curable barrier masses so that they polymerize under UV rays. However, these photosensitive additives remain in the barrier layers after curing and contaminate the environment both when stacked and when they come into contact with filling goods and are therefore unsuitable for food and pharmaceutical packaging materials because they are physiologically classified as questionable. Such contamination problems do not arise when curing or crosslinking with ionizing radiation.

However, the radiation-curable barrier compositions known according to the current state of the art have the disadvantage overall that they have a relatively high proportion for processing reasons

Must contain (meth) acrylic group-containing monomers as reactive diluents. These (meth) acrylic monomers can be more or less physiologically questionable. Some of them are also classified as toxic. One of the biggest disadvantages, however, is the taste and odor-influencing component with regard to the environment, the filling goods, especially in the food and pharmaceutical sectors, which are caused by residual monomer contents, even at very low ppm values.

The barrier materials described above will make it difficult for an expert in the future, either from an economic or technical point of view, to provide barrier layer equipment under environmentally friendly and optimal hygienic conditions, because the state of the art does not offer total solutions that meet all requirements. Particularly in the field of packaging for food and pharmaceuticals, high demands are made, as is only the case from the recommendations of the federal government health office (BGA) "plastics in food traffic" or from the legal provisions of the Food and Drug Administration (FDA) and the individual environmental laws. An additional problem can also be the additives required in conventional corrosion protection agents, as in Gächter / Müller "Plastic Additives", 2nd edition, Hanser-Verlag, Munich, 1983, in Chapter 18 "Commercial and Food Hygiene Aspects of Plastic Additives" is described. This problem is particularly clear from the article by Piringer et on the topic "The influence of residual solvents and monomeric acrylates from packaging on the sensory properties of food", Packaging Review, Issue 8/1986, pages 53-58, because it is precisely the residual solvents and the acrylic monomers have a special sensory impact on food products. The relative threshold values of inert solvents, acrylates and methacrylates with regard to smell and taste shown demonstratively show that when such low molecular weight compounds are used, these remain problematic. For example, the relative odor threshold is 0.002 for n-butyl acrylate and 0.02 mg / kg for 2-ethylhexyl methacrylate.

Furthermore, it can be said that the assessment of the legal measures and requirements in the environment, commercial and food hygiene and the like in the European Community as in the North American market and Japan are largely identical, if no nuances in the implementing provisions. Summarizing and comparative presentations include Keener, RL, Plamondon, JE and West, AS "Recent Developments in the Regulation of Industrial Chemicals in the United States and Europe", lecture RADCURE EUROPE '85, Basel / Switzerland, organizer: AFP / SME , Dearborn, Mich. 48121, USA and in the book Ronald Brickman et al "Controlling Chemicals: The Politics of Regulation in Europe and the United States" Cornell University Press, Ithaca, NY, 1985. Conventional barrier materials based on different polymers and dissolved in solvents are extensively described in the literature, such as H. Kittel "Textbook of paints and coatings", Vol. 4, 5 and 7, WA Colomb Verlagsgesellschaft mbH, Berlin and Oberschwandorf, and therefore this state of the art does not have to be particularly appreciated.

Equipping with barrier layers of flat substrates and / or moldings, in particular of metals and cellulose materials, with coating agents that are free of inert solvents is also well known in industrial practice. For this purpose, coating agents were used in which the backbone polymers are dissolved in reactive diluents or the base products are in such a liquid state that they can be applied. Although these reactive diluents and / or other liquid coreactants are integrated into the polymer matrix by curing or crosslinking, free residues still remain, depending on the degree of crosslinking. In many cases, these residues that have not been installed cannot be removed by additional and expensive cleaning processes or reduced to a level that they comply with the legal requirements. Since they can also be physiologically questionable, such barrier materials can only be used to a limited extent, with the food and pharmaceuticals area being completely excluded. This is due to the fact that the contents are influenced by sensors, ie taste and smell. By baking and / or post-curing it is also possible to achieve qualitative improvements in non-thermosensitive substrates, but these are often not sufficient to achieve the required minimum standard. Added to this are the additional cost burdens for end products due to such post-treatment measures. For this reason, efforts were made to develop better technical solutions using radiation curing, which at the same time also ensure cost-effectiveness. Because of the minimum degree of networking that cannot be achieved under economic conditions - as already mentioned above - it was possible to use these radiation-curable coating materials are not the hoped for

Breakthrough can be achieved.

Another European patent application 0 184 345 describes radiation-curable, thermoplastic coating compositions for wood and other substrates which consist of copolymerizable ethylenically unsaturated polyesters and thermoplastic polymers. In order to be able to process them as coating compositions, monomers or reactive thinners and / or inert organic solvents are necessary. This presents coating compositions which, although they can provide good final properties, are associated with the problems of evaporation of the inert solvents and those of the residual solvent and monomer contents.

To form barrier layers, so-called hot melt coatings have also become known, which are based on inert resins, waxes, thermoplastics and / or elastomers. In German, the use of the unconnected term "hot" is not recommended (see Römpp's Chemie-Lexikon, 8th edition, volume 3 (1983, page 1763), therefore only from

Enamel masses spoken. While the hot melt adhesives related to the hot melt have become very important in many industries, the hot melt has remained relatively insignificant, apart from some areas of application, such as corrosion protection films. These anti-corrosion films are made from a hot-dip material that includes consists of cellulose esters, plasticizer mixtures and mineral oil additives, e.g. if Dip tool parts, machine parts into the hot mass and then let them cool down. The film or coating that forms can later be removed without residue.

Regardless of whether it is enamel for coating or adhesive purposes, the thermoplastic base materials including the resins and plasticizers are thermosensitive and exposed to thermal oxidation, particularly in the presence of atmospheric oxygen. This not only changes the product properties, it also creates crack products that are physiologically questionable. This associated thermal problem is described in international terminology with the term "heat history". While with the

Hot melt adhesives can be worked with stabilizers and antioxidants, they can only be used in the melt masses if they are used in the technical field. Covering with protective gases such as nitrogen (N ₂ ) can also reduce thermo-oxidative degradation. Another disadvantage of the thermoplastic melt coating compositions is the relatively low softening points, which are preferably below + 150 ° C., in particular below + 120 ° C. Another disadvantage is that the backbone polymers are already in their final state as a macromolecule and therefore very high processing temperatures of + 180 ° C to + 270 ° C are necessary to achieve adequate wetting and thus adhesion to the different substrate surfaces. Certainly there are masses melting even at low temperatures, but they do not have heat resistance and the chemical resistance is not always sufficient. Such melt coating compositions are described, inter alia, in DE-OS 24 25 395, which are formulated on the basis of ethylene-vinyl acetate copolymers. Further enamel masses are in the monograph R. Jordan

"Schmelzklebstoffe", Volume 4a (1985) and Volume 4b (1986), HINTERWALDNER-VERLAG, Munich. These also include polyester melt compositions which are based on linear copolyesters of terephthalic and / or isophthalic acid and can be from amorphous to crystalline (DE-OS 24 14 287).

DE-OS 19 17 788 and 31 06 570 describe radiation-sensitive telomerized or acryloxy- or methacryloxy-terminated polyesters, which are preferably made from aliphatic and cycloaliphatic and only partially from aromatic polycar bonic acids and polyhydric aliphatic alcohols. They are very linear and can only be hardened with rays under difficult conditions. Since the relative distances between the acrylic and methacrylic groups increase with increasing molecular weights in the case of linear molecules, the energy requirement required for crosslinking or curing also increases. Despite this increased energy requirement, good cross-linking is not guaranteed so that a degree of cross-linking of less than 90% is achieved. If, on the other hand, low molecular weight polymers or monomers are used, a relatively sufficient degree of crosslinking can be achieved, but such coatings are extremely brittle and therefore sensitive to impact and impact and are not deformable. Additional stresses can arise in the coatings, which then at least lead to the formation of fine hairline cracks.

The same applies to the resistance to higher molecular weight linear polyesters, although their hardened coatings can be more elastic. One of the main points of attack is the still free, uncrosslinked reaction groups.

A further significant disadvantage is the thermal sensitivity and the rheological properties, especially when it comes to high molecular weight linear polyesters. Because these decompose very oxidatively with increasing temperature.

The critical parameters associated with the "heat history" on the one hand and the improvement of the final properties, e.g. Heat resistance, on the other hand, to get a better grip, reactive enamel compositions have also been proposed. These enamels are preferably adhesives and sealants, which are analogous to an enamel from one

Melt can be processed at temperatures below ≤ 150 ° C, in particular ≤ 100 ° C and can thus be functionally handled at an early stage, but their cross-linking function is only triggered by the ambient humidity. This is it preferably around moisture-curing polyurethane systems. Depending on the layer thickness and ambient humidity, curing takes between 1 and 96 hours. For an industrial production an undiscutable hardening phase, apart from the fact that uncrosslinked hardener parts can migrate.

European patent 0 270 831 describes solvent-free, low-monomer or non-polymerizable, meltable masses based on (meth) acrylated cellulose esters and polyesters, which may include can be used to form barrier layers on flat substrates. But now an effective barrier layer against oxygen and

To be able to build up water vapor, layer thicknesses of ≥ 50 µm, in particular ≥ 100 µm, are required. Despite these layer thicknesses, e.g. the oxygen permeability only by a factor of 10 to 20 on substrates made of polyethylene and / or polypropylene. With substrates made of polyesters (e.g. Melinex) there is no improvement in the barrier properties. This

Enamel materials were also designed for other tasks. Since these enamels are also processed at temperatures ≥ 80 ° C, especially ≥ 140 ° C, they are also thermosensitive.

The reasons for the negative evaluation are certainly not to be found solely in the so-called "heat history", but rather in the lack of suitable raw materials. In order to meet the continuously updated legal requirements to improve the environment, food and work hygiene and sensory problems, more preventive measures alone are not enough, because on the one hand these are associated with higher investment costs in systems, measuring devices and the like and on the other hand with costly monitoring . Therefore, for better ecology as well as in terms of work and food hygiene, it is better to eliminate these existing and the tasks facing us in that the causes are as far as possible eliminated and still ensures a high level of efficiency. Despite these numerous efforts, it has so far not been possible to determine highly effective, food-safe barrier layers, in particular against oxygen and water vapor, for flat substrates or moldings from the extensive range of products and processes according to the prior art, which are also economical.

Regardless of the above barrier compositions described in the prior art, which are processed from solutions, aqueous dispersions and melts, a large number of other barrier polymers are known in industrial practice. The barrier polymers can be classified according to Römpps Chemie-Lexikon, 9th edition, volume 1, page 349 - as follows:

 The barrier polymers are processed using various process technologies, e.g. by injection molding, compression molding, blow molding, rotary molding, thermoforming and the like. Since individual barrier polymers rarely have multiple barrier properties, so-called “composite films” or “composite laminates” have to be produced from different substrates by coextrusion and / or gluing.

The specific properties of the individual barrier polymers are adequately described in the relevant literature. A current overview of barrier polymers is provided by William J. Korosin "Barrier Polymers and Structures", ACS Symposium Series 423, Washington, DC, 1990, ISBN 0-8412-1762-9. EP-A1-0 547 551 describes edible films (edible films) which consist of modified starches, gelatin, plasticizers, lipids and water. These films are said to have physical or microbial barrier properties in food against water, solutes, gas and water vapor. Depending on the type, content and film thickness

Water vapor permeabilities of ≥ 7% determined. The starch / gelatin mixture still has a value of 25%. The gas barrier properties are not supported by any values. In addition, the film base materials consist of multi-component mixtures that are complicated and relatively expensive to manufacture and use. These barrier properties are unacceptable for the packaging industry, especially for sensitive foods and pharmaceutical products.

The permeability of the barrier polymers to water vapor and gases is of particular importance for the durability of perishable goods. This permeability is not a leak in the classic sense of porosity and / or capillary holes, but the so-called

"Solution Diffusion". In this case, the gas dissolves in the barrier polymer like in a liquid, migrates through it and emerges as gas on the other side. This diffusibility does not depend on the thickness of the barrier layer, but only on the barrier polymer. The thickness of the polymer barrier layer is only a time factor.

With moisture-absorbing barrier polymers, such as polyamide, cellulose acetate, gases diffuse more easily due to the increased degree of moisture, because these can also dissolve in the moisture itself. The barrier polymers are assessed according to their permeability coefficients. When summarizing the partially briefly described prior art, the person skilled in the art finds that the use of barrier polymers is a very complex field both in processing and in application. Added to this are the ecology see environmental and recycling problems and the constant effort to reduce the volumes of barrier polymers required.

The following list is a typical example from the food and beverage sector for the requirements for barrier materials against oxygen and water vapor in order to achieve a storage stability of 1 year at 25 ° C (Plastics Engineering, May 1984, page 47).

The known barrier polymers have very different barrier properties, especially against oxygen and water vapor. Only in a few applications do they meet the required barrier properties as a simple layer. In order to be able to meet the catalog of requirements of the packaging industry, which does not only include the barrier properties, so-called multiple coatings, composite films or laminates have to be produced from the barrier polymers and / or the surfaces thereof have to be metallized. Only through these measures can barrier properties be achieved that are comparable to those of aluminum foils. However, such multilayer connections are subject to technical and economic limits because - The packaging weight and thus the barrier polymer requirement increases

 - Disposal and / or recycling is made difficult and

 - An economy for the manufacturer and user is no longer guaranteed.

Further aspects in the selection of barrier polymers, especially when used as packaging materials for everyday consumer goods, are the legal requirements and / or self-restrictions of manufacturers and consumers on ecology and the environment. This fact has already resulted in e.g. Polyvinyl halogens, e.g. PVC and PVDC, as barrier polymers in packaging materials are no longer permitted. Although the measure reduces the number of barrier polymers that can be used, the spectrum that is available in practice cannot be covered with the remaining barrier materials. This is especially true when very high barrier properties, i.e. e.g. very low oxygen and water vapor permeability values are required. In practice, there are a multitude of needs where the requirements - even of high-quality barrier polymers - can no longer be met.

However, efforts are also being made to improve the barrier properties of packaging materials by means of transparent vapor deposition layers made from oxides of Si, Al and Mg. However, not all tasks set by the packaging industry can be solved in this way. See Coating, Issue No. 8, 1994, pages 274 to 280.

The prior art described above on barrier equipment and reasons relating to ecology, the environment and industrial hygiene are reason enough for the barrier polymer processing and applying industry, in particular from the food and pharmaceuticals sector, to look for technically and economically simpler solutions with further improved barrier properties, in order to be able to produce packaging substrates with very low basis weights.

The object of the present invention is to provide barrier materials which avoid the above disadvantages and which meet the requirements defined in Table 1 with only a single layer.

In particular, problems with sensor technology, ecology, disposal and / or recycling should also be remedied. The areas of application in the food, pharmaceutical and commercial hygiene sectors include a focus.

This object is achieved according to the invention by a water-resistant barrier material which comprises natural, biodegradable hydrocolloids which are mono- or polysubstituted by ethylenically unsaturated and / or epoxy-containing radicals, and the hydrocolloids are hardened and / or crosslinked by means of a polyreaction which relates to the radicals .

It has now surprisingly been found that high-quality barrier materials with superior, advantageous properties are produced from hydrocolloids curable or crosslinkable by a polyreaction, in particular polymerization and / or polyaddition, which are substituted with mono- or poly-ethylenically unsaturated and / or epoxy group-containing residues to let.

The adhesive starting materials according to the invention based on natural, biodegradable hydrocolloids which are mono- or polysubstituted by ethylenically unsaturated and / or epoxy group-containing residues include water-soluble, biodegradable hydrocolloids or backbone polymers A, which come, inter alia, from the following polymer families: - proteins

 Polypeptides, especially those of collagen origin, e.g. Gelatin; animal glues; Collagens; Whey proteins, caseins; Plant proteins, especially soybean, rapeseed and cereal proteins and / or their hydrolysates.

 - polysaccharides

 Cellulose and its derivatives such as methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, etc., starch and starch derivatives, glycogen, alginic acid and derivatives including salts, agar agar, hetero-polysaccharides, heteroglycans, hemicelluloses and their derivatives, chitin, gum arabic and the like.

The barrier materials according to the invention are preferably hydrocolloidal compounds of the general formula (I)

wherein A is a hydrocolloid of the above meaning, preferably with a molecular weight of about 500 to about 2,000,000,

R ^{1 is} the hydrocarbon radical of an ethylenically unsaturated, optionally hydroxy, nitrile, halogen and / or C ₁ -C ₄ alkyl-substituted carboxylic acid, preferably an acrylic, methacrylic and / or crotonic acid and / or with an α, β-epoxy group with 2 to 10 carbon atoms

X = -O-, -N (R ² ) -, -NH-C (O) - and / or the group R ¹ -C (O) -X- stands for an ethylenically unsaturated dicarboximide residue, preferably maleimide residue,

R ^{2 is} optionally hydroxy, amino, multiple R ¹ -C (O) -X-, C ₁ -C ₈ alkyl-, C ₁ -C ₈ alkoxy- and / or oxyalkyl- substituted, saturated or unsaturated hydrocarbon residue, preferably an aliphatic hydrocarbon residue and optionally -C (O) -O-, -OC (O) -O-, -O- C (O) -, -O-, -C ( O) -, -NH-C (O) -NH-,

and / or has -NH-C (O) bridge members,

R ³ = H, RC (O) -, R ² - Y - A and / or C ₁ -C ₄ alkyl,

Y = -O-, -O-C (O) -, C (O) -O-, -NH-C (O) - or -C (O) NH- n = 1 to 5 and

m = 0 to 10.

The barrier materials according to the invention are based on functionalized hydrocolloids. The starting materials include known and conventional hydrocolloids or their basic raw materials. The chemical modification of the starting materials takes place by introducing reactive and / or functional groups into the main molecular chains without changing or damaging the colloid chemical and water-soluble properties.

The barrier materials according to the invention are reactive, biodegradable hydrocolloids or backbone polymers. They are essentially reaction products from a non-radical reaction between polypeptides and / or polysaccharides, their functional groups, e.g. Hydroxyl, amino, imino, thiol and / or carboxyl groups are at least partially derivatized with a polymerized residue.

The barrier materials according to the invention are thus derivatives of esters of unsaturated carboxylic acids

and / or residues carrying epoxy groups with hydrocolloids the above groups. Those hydrocolloidal compounds which correspond to the above formula (I) are particularly preferred. In the hydrocolloidal compounds of the formula

(I) R ¹ can be the hydrocarbon radical, for example methacrylic, chloracrylic, cyanoacrylic acid and the like, with the acrylic and methacrylic acid radical being particularly preferred. Furthermore, R ^{1 can} also be an epoxy group-bearing hydrocarbon radical having 2 to 10 carbon atoms, the epoxy groups preferably being arranged in the α or β position.

Compounds in which X is oxygen are very particularly preferred.

The radical R ² contains at least one R ¹ -C (O) -X group, in which R ¹ and X can have the meaning given above and in the case of several R ¹ - (C) -

X radicals within a molecule, the radicals R ¹ or X can in each case be the same or different. Possibly existing ones

Bridge members of the radical R ² can be arranged both within the radical, in particular in the case of aliphatic radicals, R ² and / or at one or both ends as bridge members of the radical R ² to form X, Y or A. In a very particularly preferred

Embodiment R ^{2 is} an at least divalent, optionally substituted glycol or polyol residue with 2 to 6 C atoms, the divalent residue of an aliphatic oxyarboxylic acid with 2 to 18 C atoms or the divalent residue of a carboxylic acid -C ₂ -C ₆ - Is glycol or C ₆ -C ₈₀ polyalkylene glycol ester.

R ² can, for example, also be a C ₁ -C ₄ alkylene group which is optionally substituted with lower alkyl groups. The radical R ² is preferably connected to the radical Y or A via ether, ester and / or imino groups (Y = -O-, -OCO-, -COO- or NR ⁴ -). The general formula (II) has a further group of usable, highly suitable ethylenically unsaturated substituted compounds: (R ¹ - X) _n - (R ² ) _m - Y - A (II), in which R ^{1 is} an allyl or vinyl group and / or an α-, ß-

Is epoxy group with 2 to 10 carbon atoms, X, R ² , Y, A, n and m have the same meaning as before.

Compounds of the formula (I) are particularly preferably used in which - X - R ² -

- (O - [CH ₂ ] _p ) _m - O -, - O - [CH ₂ ] _p ) _m -OR ⁴ - as well as residues of the general formulas

*

and / or - (CH ₂ ) _m - can be

R ^{4 can be the} same or different and can be branched and unbranched and cyclic alkylene radicals having 1 to 20, preferably 1 to 10 carbon atoms, arylene radicals, aralkylene radicals and / or acyl radicals having 1 to 20 C atoms,

R ⁵ = H, Cl, CN, OH, C ₁ -C ₄ alkyl,

R ⁶ = - CH = CH -, -CH ₂ - CH ₂ -,

 m = 0 to 50 p = 1 to 20.

Another preferred group of compounds are such formulas

and / or - Y - Y, but at least one of the residues

and A, Y and R ^{1 have} the above meaning.

The link Y between the residues from the formula (I)

and / or (II) and the polymer main chain results from the reaction of the functional groups of the hydrocolloid A with the corresponding reactive groups of the polymerizable radical mentioned. In particular, Y has the same meanings as the hetero groups of R ² . The derivatization can take place by non-radical reaction or by grafting reactions on the backbone polymers.

The reactive groups introduced into the main molecular chains of the hydrocolloids A according to the present invention are ethylenically unsaturated and / or epoxy group-bearing radicals. These can be connected to the hydrocolloids directly or via the radical R ² , for example a divalent, optionally substituted hydrocarbon or polyol radical. The curing or polymerization is carried out by means of the reaction initiators, hardeners and / or by high-energy radiation which are customary for compounds of this type. The barrier materials can also contain further known constituents, such as accelerators, stabilizers, rheology-influencing agents, fillers, pigments and / or further polymerisable compounds or compounds which can be copolymerized with the abovementioned ethylenically unsaturated and / or epoxy group-bearing hydrocolloids, in particular compounds which carry water-soluble and / or active hydrogen atoms and the like. According to the invention, however, preference is given to the functionalized backbone polymers or hydrocolloids in which the reactive groups have been introduced into the main molecular chains via a non-radical reaction. They contribute significantly to a homogeneous barrier material, as has surprisingly been found. These functionalized products are produced, inter alia, as described in DE-A-42 10334.

The functionalization of the hydrocolloids A with one or more reactive radicals takes place in particular via their

Hydroxyl, amino, imino, thiol and / or carboxyl groups. The

Functional residues in the hydrocolloid are ≥ 0.1 mass% (m%). The particularly preferred contents are between 1 and 50 m%, in particular between 5 and 35 m%. Functionalized hydrocolloids which have at least 10 curable or crosslinkable groups per 1000 amino acid or monosaccharide units have proven to be particularly advantageous barrier materials.

A large number of ethylenically unsaturated and / or epoxy group-bearing compounds according to the above formulas are suitable for functionalizing the hydrocolloids A. Reactive radicals which, inter alia, from the groups of

- ethylenically unsaturated compounds, e.g. Acrylic acid glycidyl ester, methacrylic acid glycidyl ester, acryloxypropionic acid glycidyl ester, methacryloxypropionic acid glycidyl ester, maleic acid monomethylacryloxyethyl ester, urethane methacrylate, allyl glycidyl carbonate, (meth) acrylamide, 2-acrylamido-2-methyl-epoxydyl-methoxyl-acrylate, vinyl-methoxyl-oxy-acrylate-methyl-oxy-oxy-oxy-acrylate,

- Epoxy group-bearing compounds, such as epichlorohydrin, butyl diglycidyl ether, 1,6-hexanediol diglycidyl ether, neopen tylglycol diglycidyl ether, polypropylene glycol diglycidyl ether, vinylcyclohexene diepoxide, are introduced into the hydrocolloid A. Compounds which are water-soluble and / or readily dispersible in water are particularly preferred for functionalization.

The polymerization required for curing can be carried out as a pure homopolymerization of a derivative containing the above radicals, but also by copolymerization of a mixture of such derivatives. However, the hydrocolloids according to the invention can also copolymerize with water-soluble or water-dispersible unsaturated and / or epoxy group-bearing monomers, oligomers and / or polymers. Here, these co-reactants include the function of a crosslinker. These cross-linking connections can be, for example, the above ones used for functionalization or others. For the crosslinking of hydrocolloids carrying epoxy groups, furthermore, compounds are suitable which have active H atoms in the molecule and e.g. harden by polyaddition, unless cationic polymerization is preferred. Such connections include Polyamines, polyimines, polyamides, polyamidoamines, polysulfides, silicon-hydrogen compounds and the like. Polyols, in particular water-soluble polyols, are also suitable for the cationic polymerization, which additionally have a "softening" or

Deliver "plasticizing" component in a cured polymer matrix.

The curing or polymerization of the barrier materials according to the invention itself takes place via a) in the case of ethylenically unsaturated residues by free-radical polymerization

- In the presence of reaction initiators 1. inorganic peroxides, such as alkali and / or

 Alkaline earth metal peroxides, and hydrogen peroxide;

 2. organic peroxides and / or hydroperoxides,

 such as. Benzoyl peroxides, cumene hydroperoxides;

 3. Peroxyacids and their salts, e.g. Peroxodisulfuric acid, sodium peroxodisulfate (persulfate); - Actinic light, especially UV rays in the

 Wavelength range 380 to 100 nm in the presence of photoinitiators, e.g. Benzophenone, benzoin ether, Michler 's ketone, methylthioxanthone, ketals and

 optionally other synergists, e.g. Amines, tert. Amino alcohols and / or - using electron beams in low energy

Acceleration range from 150 to 300 keV and a preferred, effective penetration depth of 3 to 400 g / m ² , as well as a dose distribution from 5 Kgy to 100 Kgy, in particular 10 to 70 Kgy and a dose spread of approx. ± 3%. b) in the case of residues carrying epoxy groups - by polyaddition with active H atoms

 Connections, as already mentioned above with the

 Crosslinkers mentioned, e.g. Isophoronediamine, diethylenetriamine, 4, 4-diaminodiphenylmethane - by cationic polymerization and actinic light in the presence of Lewis and Bronsted acids,

Carbonium ions and trialkyloxonium salts, such as, for example, bis- [4- (diphenylsulphono) phenyl] sulfite bis-hexafluorophosphate, η-2,4- (cyclopentadienyl) [1,2,3,4,5,6-η) - (methylethyl) benzene] iron (II) hexafluorophosphate. Furthermore, the polymerization and copolymerization can be accelerated by adding an accelerator after adding one or more reaction initiators, especially if curing is carried out at temperatures 25 25 ° C. Accelerators based on tertiary amines such as diethylaniline, diethyl p-toluidine, triethylene amine, heavy metal salts such as cobalt acetylacetonate are suitable for this purpose. Water-soluble or water-emulsifiable accelerators, such as triethanolamine, are particularly preferred.

The curing or crosslinking of the ethylenically unsaturated residues in the barrier materials according to the invention by means of free-radical polymerization, in particular in the case of thin layers, in an inert protective gas atmosphere made of nitrogen (N ₂ ),

Carbon dioxide (CO ₂ ) and / or noble gas to suppress oxygen inhibition. If, on the other hand, layers, coatings, films and foils or the like made of the aqueous barrier materials according to the invention are cured or crosslinked before dehydration or drying, an inert protective gas atmosphere can be dispensed with, as has surprisingly been found. Because the existing water content creates its own self-sufficient protection zones against molecular oxygen (O ₂ ). This procedure also has the further advantage that the subsequent dehydration or drying can be made technically simpler and thus more economical.

Regardless of the above, additional reactive groups can be cross-linked in the main molecular chains of the hydrocolloids. Suitable for this purpose include bi- and / or polyfunctional isocyanates and the like, but also aldehydes, such as glutaraldehyde. However, dual and hybrid curing can also be carried out with the barrier materials according to the invention, provided that the functional groups for this have been functionalized with the appropriate radicals and / or contain other reactive links in the main molecular chain. Particularly suitable crosslinking agents (crosslinkers) for copolymerization with the hydrocolloids according to the invention include monomeric and / or oligomeric mono-, bi-, tri- and polyfunctional (meth) acrylic compounds, in particular those with molecular weights (M _W ) 500 500. This group includes, among others aliphatic and / or cycloaliphatic urethane (meth) acrylates, polyether (meth) acrylates, acrylamido-2-methylpropanesulfonic acid. If these compounds are not water-soluble, they are advantageously added to the barrier materials according to the invention in the form of aqueous dispersions. Already additions from

25 25.0 m%, preferably 10 10.0 m%, in particular 5,0 5.0 m% of urethane (meth) acrylates again lead to significant reductions in permeation, especially with respect to oxygen, as has surprisingly been found.

The barrier materials according to the invention can optionally be modified by further additives. First of all, known additives are pigments to give the barrier materials a colored appearance. The term “pigments” is understood in general to mean dyes, coloring compounds, fillers and extenders of all types, which provide the inventive barrier materials with additional solids and, if appropriate, also make them printable. At the same time, they give the barrier materials a number of specific properties.

When the pigments are used in barrier materials that will later be used in the food and pharmaceutical sectors, they must comply with the respective food and pharmaceutical law. The respective properties and functions are summarized in "Pigments and Fillers", 2nd edition, 1980, MuO Lückert, Laatzen. The content of pigments and fillers can be between 0.5 and 80, preferably 1.0 and 70% by weight. The barrier materials can also contain plasticizers. Particularly suitable plasticizers are water-soluble products, such as polyols, such as, for example, diols, glycols, glycerol, sorbitol, inositol and other sugar alcohols, which may have reactive groups according to the above formula.

For the use in the technical field, the barrier materials according to the invention can contain further additives, e.g. Stabilizers, antioxidants, leveling and wetting agents are added. The additives are adequately described in the literature, so that the above book Gächter / Müller

"Kunststoff-Additive", 2nd edition, Hanser-Verlag, Munich, 1983. If, on the other hand, additives are required for barrier materials that are used in the food and pharmaceutical sectors, the applicable legal regulations must be observed. The amounts added are generally between 0.1 to 5.0, preferably 0.1 to 2.5,% by weight, based on the solids content. Since the physical characteristics are not changed by the derivatization of the hydrocolloids, the barrier materials according to the invention offer a further advantage when processing and producing barrier layers and films because they remain water-soluble or water-dispersible. Only through hardening or crosslinking are these properties partially or completely eliminated, depending on the content of reactive groups. Thus, the person skilled in the art is provided with a barrier material with which he is familiar and whose properties he knows.

The barrier materials according to the invention are in solid form as powders, granules and the like or as aqueous gels, solutions and / or dispersions. For processing they have to

- In the case of solid molds, wetted beforehand with water, if appropriate swollen, then melted in the heat and / or dissolved in water and - The aqueous gels are melted by means of heat and are thus brought into the sol state.

Since the processing takes place from aqueous solutions and / or dispersions, the hydrocolloids according to the invention are particularly environmentally friendly from this point of view.

The crosslinking co-reactants, reaction initiators and optionally other additives and / or additives are also added and incorporated in an aqueous, liquid phase in the hydrocolloids according to the invention. For this purpose, simple mixing containers with suitable mixing tools can be used, which, if necessary, must be heated to melt the gels. The preparation and processing can also be carried out continuously, which includes Extruders, mixing screws are suitable.

If the barrier materials according to the invention include gases, e.g. Air, must be degassed with a vacuum before application.

Another object of the invention is the equipping of substrates with the polymerizable barrier materials according to the invention or the production of self-supporting barrier films. The polymerizable barrier materials according to the invention are used, inter alia, to form layers for flat substrates and moldings. out

Cellulose materials, such as Paper, cardboard and cardboard of all kinds,

- Plastics, such as foils and sheets made of polyvinyl alcohol, polyethylene, polypropylene, polycarbonate, polyester, polyvinyl esters, polyamides, polyvinyl halides and their copolymers, as well as fiber composites Thermoplastics and thermosets, but also

- for other materials, such as metals, inorganic materials, e.g. Glass and the like. In particular, they are suitable for porous and / or non-diffusion-tight substrates in order to give them the necessary barrier properties. As was surprisingly found, the barrier materials according to the invention are also particularly suitable as so-called top coats of substrate surfaces equipped with vapor deposition layers of metals or oxides of silicon (Si), aluminum (Al) and / or magnesium (Mg), because they have their gas and Improve water vapor impermeability values again by very high factors.

The barrier properties of the barrier materials according to the present invention can be varied within wide limits. In addition to the

- Content of reactive radicals or groups - according to the above formula and / or

- The respective layer thicknesses, if necessary as a time-dependent influencing factor, the barrier properties are essentially determined by the type of hydrocolloids according to the invention and their dehydration behavior, as has surprisingly been found. Particularly high permeation reductions are provided by hydrocolloids which, from their aqueous solutions and / or gels, do not dehydrate or dry via pores or capillary activities, but rather via diffusion processes. These preferably include such hydrocolloids according to the invention which form gels or are subjected to a sol / gel transformation in the uncrosslinked state and have a content of reactive groups of between 20 and 50% by weight. In particular, those hydrocolloids according to the invention which are of collagenic origin, for example gelatin, are suitable. The barrier properties of the hydrocolloids according to the invention can optionally be further improved if

- in addition to hardening or crosslinking, the above-mentioned and / or other known crosslinking agents are also used and / or

- Dual and / or hybrid hardenings are carried out.

The dehydration or drying of the uncrosslinked and crosslinked layers, coatings, films, foils or the like also has an influence on the polymer network formations and their barrier layer properties. The dehydration or drying is therefore carried out under conditioned climates, with pre-dried air with a relative humidity of ≤ 40% and low temperatures ≤ 100 ° C. being particularly preferred.

The cured or crosslinked barrier materials, films and / or films according to the invention have a dependency

- their hydrocolloid base,

 - the respective degrees and densities of cross-linking and

 - Different barrier properties and functions depending on the layer thickness selected. You can thus form barrier layers with excellent functionalities against a variety of gases, vapors and / or liquids, e.g. Oxygen-containing gases and vapors, but also water vapor and volatile vapors form a focus.

The barrier materials according to the invention also have good resistance to organic solvents, such as alcohols; Oils and fats; as well as a variety of weak acids and bases. The chemical resistance is essentially influenced by the basic hydrocolloid, the degree of crosslinking and the crosslinking density. Compared to water or water-containing liquids, the hardened or crosslinked barrier materials according to the invention have greatly reduced requellabilities, which may also have a positive effect on the barrier properties, as has surprisingly been found.

Innovative, high-quality barrier layers can be produced with the barrier materials according to the present invention. These barrier layers according to the invention provide barrier factors which can be up to 10 ⁷ higher than their unmodified basic hydrocolloids. These potential improvements were surprising because the barrier factors of the unmodified hydrocolloids are generally ≤ 10 ² . Depending on the carrier material, its surface pretreatment and the barrier material according to the invention, permeation values can be determined, among other things

- with oxygen (O ₂ ) of ≤ 0.1 ml / (m ² x 24 hx bar)

 (ASTM D 3985-81)

- with water vapor of ≤ 0.3 g (m ² x 24 hours)

 (ASTM 372-78).

The barrier materials according to the invention adhere to a large number of substrate surfaces. A surface pretreatment may be necessary to improve the wetting and adhesion of the surfaces to be coated. This is particularly the case when these surfaces are non-polar, such as with polyolefinic substrates. Flame treatment, corona discharge, low-pressure plasma and / or adhesive primer are suitable for surface pretreatment.

Self-supporting barrier films and foils can be made from the barrier materials according to the invention, among others. by pouring onto an adhesive base, then hardening or crosslinking and dehydrating. The process conditions are analogous to the above.

The hydrocolloids according to the invention lose their hydrocolloidal properties as a result of curing, crosslinking and / or polymerizing. That the layers, coatings, films, foils and the like produced in this way are no longer water-soluble and / or water-dispersible, but instead deliver, inter alia, boiling water-resistant and possibly sterilization-proof network polymers. Furthermore, the temperature-dependent reversible transforms into an irreversible sol / gel transformation. In water, the polymer networks can still have a relatively weak self-swelling.

The new polymer networks include resistant to water, water-containing media, salt solutions, weak acids and bases, sugar solutions, fruit juices, milk, alcoholic beverages, soft drinks, milk and milk products, oils, fats, organic solvents and are therefore particularly suitable for equipping packaging materials and packaging materials made of different materials . But also sensor-sensitive products, such as Coffee, fruit powder and the like offer excellent protection to the barrier layers because they are diffusion-tight against a large number of aromatic media.

The hardened barrier layers, coatings, films and foils are sensor-neutral and do not have or have a so-called "scalping effect" against any filling goods or the like. The barrier materials according to the invention hardened by means of UV and electron beams are additionally sterile.

The new polymer networks, which were formed by curing, crosslinking and / or polymerizing the barrier materials according to the invention, have furthermore remained biodegradable, as has surprisingly been found. By adding enzymes, the hardened barrier materials can be broken down in an acidic or alkaline environment within a few days. When buried in the ground or when composting, biodegradation takes several days to a few weeks.

In many branches of the commercial economy and industry, such and other substrates with a barrier protective film are required. These include the packaging and packaging industry, vehicle industry, aerospace, construction, etc.

Special areas of application for additive-, monomer-free, polymerizable barrier materials according to the present invention are the packaging and packaging areas for food and pharmaceutical products. In order to be able to provide packaging and packaging materials for these fields of application in the future, they not only have to be manufactured and processed under stricter legal requirements, but they also have to meet the increased requirements of food and pharmaceutical legislation in terms of their physiological and sensory behavior. In order to achieve this goal, new barrier materials as coating compositions are necessary, which are based on other innovative, new technologies. According to the present invention, this object can be successfully achieved technically and economically with the, in particular additive and monomer-free, polymerizable barrier materials because:

- Their starting hydrocolloids are natural polymers and predominantly foodstuffs and are not modified by the derivatization of their properties and technical characteristics be and

- It is only surprisingly found that new, polymeric networks with extraordinarily high barrier properties against gases, water vapor and a large number of other media form through the hardening, crosslinking and / or polymerization. These polymeric networks which form according to the invention already have barrier properties in very thin layers or films, such as less than 10 μm, such that they can be assigned at least to the above 1st barrier class. Furthermore, it was completely surprising that the already excellent barrier properties of the substrates equipped with vapor deposition layers of metals and oxides of Si, Al and MG after the application and hardening of the barrier materials according to the invention as topcoats can be further improved by factors 10 10 ¹ .

Furthermore, the barrier materials according to the present invention can be used to produce porous and / or absorbent substrates, such as e.g. Impregnate cellulose materials, in particular paper, cardboard, cardboard, wood, wood-based materials and the like, in order to give them highly functional barrier properties.

According to the present invention, new, innovative barrier materials are created which are not comparable to the known barrier polymers. This not only largely eliminates the described and other known disadvantages, but also completely new barrier polymers and materials are provided which are better able to cope with current and future aspects and requirements, particularly in the food and pharmaceutical sectors. This new class of barrier polymers according to the present invention offers the following advantages, among others: - natural polymers available from national resources

- The starting hydrocolloids are preferably foods or approved additives for foods

- Can be processed like their basic colloids

- biodegradability

- After curing, crosslinking and / or polymerizing, monomer-free polymer networks are formed which are resistant to boiling water and sterilization

- High economic efficiency, since layers ≤ 10 μm have high barrier functions against gases and liquids

- Improvement of the barrier factors up to 10 ⁷ .

In comparison with the barrier polymers described above and other prior art polymers, the barrier materials according to the present invention are potentially superior to them and thus make essential contributions to improving the ecology, environment and waste disposal and are physiologically and toxicologically much safer.

The invention is explained in more detail by the following examples, but without being restricted thereto.

example 1

100 g of derivatized high-bloom type A gelatin with a methacrylate content of 14 mmol / 100 g of 20% aqueous gel was at 50 ° C. with 0.5 ml of 50% aqueous triethanolamine and 5 ml of 10% Na ₂ S ₂ O ₈ solution The batch polymerized 40 seconds to a water resistant gel. Temperature increase (60, 70 ° C) led to short reaction times (10-20 seconds) - batches without the addition of amine polymerized more slowly.

Example 2

Derivatized, high-bloom type A gelatin with a methacrylate content of 28 mmol / 100 g of 20% aqueous gel was mixed with 50 ml of 50% aqueous triethanolamine and 5 ml of 10% Na ₂ S ₂ O ₈ solution at 50 ° C. The batch polymerized for another 25 seconds. As in Example 1, increasing the temperature led to shorter reaction times, while batches without the addition of amine polymerized more slowly.

Example 3

A photoinitiator (Irgacure 184 = 1-hydroxy-cyclohexyl-phenyl-ketone) was added to derivatized high-bloom type A gelatin with a methacrylate content of 45 mmol / 100 g of 20% aqueous gel. The photoinitiator concentration was 0.5% by weight. The mixture was applied to paper with a hand knife and irradiated with a high-pressure mercury lamp (power 120 W / cm). Solid, boiling-water-resistant layers were produced at a throughput speed of 13 m / min.

Example 4

Derivatized high-blooming type A gelatin gels (20% W / W) of the types given in Table 2 were applied to 210 g / m ² cardboard by hand knife and irradiated with 180 keV electrons. The radiation dose was 40 kGy. The O ₂ - and

N ₂ permeability of the cardboard coated with cross-linked gelatin. The ratio becomes the barrier factor for O ₂ Q ₂ permeability of the substrate

O ₂ permeability of the coated substrate

 specified.

 Example 5

Derivatized high-blooming type A gelatin of the types listed in Table 3 was applied with a hand knife on polypropylene (PP) -

Films with a thickness of 25 μm were applied and irradiated with 180 keV electrons. The radiation dose was 40 kGy. Permeabilities and barrier factors were measured.

Example 6

Derivatized high-blooming type A gelatin of the type given in Table 4 was applied with a hand knife to polyester film precoated with SiOx and irradiated with 180 keV electrons. The radiation dose was 40 kGy. The oxygen permeability of the gelatin-coated film was measured.

Example 7

Derivatized Type A gelatin of the types listed in Table 5 was mixed with aqueous dispersions of various monomeric and oligomeric acrylates such as TMPTA, polyether acrylates and polyester acrylates. The acrylic concentration was between 1 and 10% by weight. The mixtures were applied to 60 g / m ² paper with a hand knife and irradiated with 180 keV electrons. The radiation dose was 40 kGy. Table 5 shows barrier factors and O ₂ permeabilities of the coated ones

Specified substrates and compared with measured values for pure gelatin coatings.

Example 8

The biodegradability of the irradiated, i.e. cross-linked coating material, was tested by in vivo and in vitro tests.

The in vitro test includes the treatment of the coating material in the form of films with a thickness of 20 μm with the protease pepsin at 37 ° C. over a period of 7 days. Depending on the radiation intensity used for the crosslinking, there are different mass changes, based on the starting mass after the enzymatic hydrolysis.

In a modification of the burial test from DIN 53739 according to method D, an earth burial test under anaerobic conditions was used for the in vivo investigation.

It enables the qualitative and semi-quantitative determination of the biodegradability by soil bacteria and fungi from test specimens made of biological or synthetic polymers.

Claims

PATENT CLAIMS

1. Water-resistant barrier material for the long-term stabilization of filling goods, wherein the barrier material comprises natural, biodegradable hydrocolloids, which one or more times by ethylenically unsaturated and / or

 Residues bearing epoxy groups are substituted, and the substituted hydrocolloids are hardened and / or crosslinked by means of a polyreaction involving the residues.

2. Barrier material according to claim 1, characterized in that the hydrocolloids are polypeptides of collagen origin, in particular gelatin, animal glues, collagen and caseins, whey proteins and / or their hydrolyzates.

3. Barrier material according to claim 1, characterized in that the hydrocolloids are polypeptides of plant origin, in particular soy proteins or rapeseed proteins.

4. Barrier material according to claim 1, characterized in that the hydrocolloids are polysaccharides, in particular cellulose, starch or derivatives thereof.

5. Barrier material according to one of claims 1 to 4, characterized in that the substituted hydrocolloid compounds of the general formula (I):

6. wherein A is a polysaccharide or polypeptide, preferably with a molecular weight in the range between 500 and 2,000,000,

R ^{1 is} a hydrocarbon radical of an ethylenically unsaturated, optionally hydroxy, nitrile, halogen and / or C ₁ -C ₄ alkyl-substituted carboxylic acid, preferably an acrylic, methacrylic and / or crotonic acid and / or a β-epoxy group,

X = -O-, -N (R ² ) -, -NH-C (O) - and / or the group R ¹ -C (O) -X- represents an ethylenically unsaturated dicarboximide residue, preferably maleimide;

R ^{2 is} optionally hydroxyl, amino, multiple R ¹ -

C (O) -X-, C ₁ -C ₈ -alkyl-, C ₁ -C ₈ -alkoxy- and / or oxyalkyl-substituted, saturated or unsaturated hydrocarbon residue, preferably an aliphatic hydrocarbon residue and optionally - C (O) - O-, -OC (O) -O-, -OC (O) -, -O-, -C (O) -, -NH-C (O) -

Comprises NH, -N (R ³ ) and / or -NH-C (O) bridge members,

R ^{3 is} hydrogen, R ² -C (O) -, R ² -YA and / or a C ₁ -C ₄ -

Represents alkyl group,

 Y a -O-, -O-C (O) -, -C (O) -O-, -NH-C (O) - or -C (O) NH-

Represents group, n = 1 to 5 and m = 0 to 10.

6. Barrier material according to one of claims 1 to 4, characterized in that the substituted hydrocolloids comprise compounds of the formula (II):

(R ¹ - X) _n - (R ² ) _m - Y - A (II) where R ^{1 is} an allyl or vinyl group and / or an α, β-

Is epoxy group with 2 to 10 carbon atoms, and wherein X, R ² , Y, A, n and m have the same meaning as in claim 5.

7. barrier material according to one of claims 5 or 6, characterized in that X - (O- [CH ₂ ] _p ) _m -, R ² -O- or

-OR ⁴ - means or represents radicals of the general formulas

/

C

and / or - (CH ₂ ) _m - can be

R ⁴ can be the same or different independently of one another and represents branched and unbranched and cyclic alkylene radicals having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, arylene radicals, aralkylene radicals and / or acyl radicals having 1 to 20 C atoms,

R ^{5 represents} hydrogen, chlorine, CN, OH or C ₁ -C ₄ alkyl,

R ^{6 represents} -CH = CH- or -CH ₂ -CH ₂ -, m represents 0 to 50 and p can be 1 to 20.

8. Barrier material according to one of claims 1 to 4, characterized in that the substituted hydrocolloids comprise compounds of the general formulas (III) and / or (IV):

wherein ZR ^{1 is} -C (OH) - and / or represents -YA, but at least one of the radicals has the former meaning and wherein A, Y and R ^{1 have} the meaning as in claim 5.

9. Barrier material according to one of the preceding claims, characterized in that the substituted hydrocolloids contain at least 10 crosslinkable groups per 1000 amino acids or monosaccharide units.

10. Barrier material according to one of the preceding claims, characterized in that the substituted hydrocolloids are hardened using crosslinking agents.

11. Barrier material according to claim 10, characterized in that the crosslinking agents have ethylenically unsaturated and / or epoxy-bearing compounds with a molecular weight

 ) Are ≥500.

12. Barrier material according to one of claims 1 to 11, characterized in that the substituted hydrocolloids are hardened by means of high-energy rays, in particular electron beams.

13. Barrier material according to claim 11, characterized in that the substituted hydrocolloids are hardened by means of high-energy radiation in a protective gas-free environment.

14. Barrier material according to one of claims 12 or 13, characterized in that it has been subjected to a dual curing or crosslinking.

15. Barrier material according to claim 14, characterized in that compounds containing isocyanate groups were used for the dual curing.

16. Barrier material according to one of the preceding claims, characterized in that the barrier material is post-cured and dried, the dehydration taking place under conditioned air at a relative humidity ≤ 50% and temperatures between 20 and 100 ° C.

17. Use of the hydrocolloids according to one of the preceding claims, characterized in that it is used for the production of strapless barrier films.

18. Use of the barrier materials according to one of the preceding claims as a coating and / or impregnation.