WO2007074494A1

WO2007074494A1 - Gas sorbing composite systems and methods for their manufacturing

Info

Publication number: WO2007074494A1
Application number: PCT/IT2006/000873
Authority: WO
Inventors: Chiara Vescovi; Lorena Cattaneo; Roberto Giannantonio; Giorgio Longoni
Original assignee: Saes Getters S.P.A.
Priority date: 2005-12-27
Filing date: 2006-12-22
Publication date: 2007-07-05
Also published as: US8153553B2; RU2417122C2; KR20080090473A; CN101432352A; EP1966297A1; CN101432352B; RU2008130896A; EP1966297B1; CA2633394A1; JP2009521326A; KR101209829B1; US20080312072A1; ITMI20052496A1

Abstract

A gas sorbing system formed by gas sorbing components which are dispersed in a polymeric matrix being porous or permeable to the gases to be sorbed is described, wherein the gas sorbing components consist of a central nucleus, selected between a silica particle, polyhedral oligomeric silsesquioxane and a spherosilicate, to which there are bound at least one organic or metalorganic radical carrying a functional group which is able to chemically fix the gas to be sorbed and1 at least one anchoring organic radical consisting of a chain of carbon atoms which has the functionality of fixing the nucleus in the matrix polymer.

Description

"GAS SORBING COMPOSITE SYSTEMS AND METHODS FOR THEIR

MANUFACTURING"

The present invention relates to gas sorbing composite systems, as well as to methods for their manufacturing.

Gas sorbing systems and materials are widely used in the industry in all applications where it is necessary to keep vacuum or to control the composition of the gaseous atmosphere by means of the removal of traces of undesired gases, particularly in displays being used as screens for television, computers, or in many other electronic applications such as hand held computers, mobile phones and the like. A particularly important case of displays are the OLEDs (Organic Light Emitting Diodes), being described for instance in the patents US 5,804,917 and US 5,882,761, and in particular those belonging to the latest generation, known as "Top Emission OLED" (TOLED); in the latter it is foreseen that the light leaves the device passing through the surface which is opposed to the one where the system being in charge of forming the image is located, that is from the surface being most suitable for housing the getter system. In this case, the getter system has obviously to be transparent. Because of their importance, in the following, particular reference will be made to these latter type of displays, but the teachings of the invention have a more general applicability, for instance in the case of plasma screens.

Gas sorbing materials used in the industry, normally, are inorganic compounds in a finely dispersed form, in order to increase the specific surface (surface area per weight unit) and thus the capability and speed of interaction with the surrounding gaseous environment; examples of these materials are alkaline-earth metal oxides such as CaO and BaO (for moisture sorption), zeolites (for the sorption of different gases, such as moisture, carbon oxides or others, depending on the specific zeolite being used), aluminas or the like. A common problem of these materials is that powders are not provided with sufficient cohesion, such as to form compact bodies; this is particularly true in the case of desiccants after moisture sorption. The problem is normally addressed by dispersing the sorbing material within a dispersant matrix, being able to keep material particles in a fixed position while at the same time allowing gases to pass towards the getter itself. Examples of this solution are reported in numerous documents. Japanese patent application JP 60-132274 discloses desiccant materials dispersed in a silicone matrix; patent US 3,704,806 discloses desiccant compositions comprising zeolites dispersed within a matrix consisting of a thermosetting polymer, such as epoxy resins; patent US 4,081,397 discloses a desiccant system comprising alkaline-earth metal oxide particles dispersed in an elastomeric polymer; patent US 5,304,419 discloses desiccant compositions comprising a desiccant material dispersed in a matrix which can consist of silicone, polyurethanes or similar polymers; patent US 5,591,379 discloses desiccant compositions comprising a desiccant selected among zeolites, alumina, silica gel, alkaline earth metal oxides and alkaline metals carbonates, which is dispersed in a matrix of porous glass or ceramic; patent US 6,226,890 Bl discloses desiccant systems wherein a desiccant material (e.g. an alkaline- earth metal oxide) is dispersed in a polymer which in the patent is said to have the property of not decreasing or even increasing water sorption speed by the desiccant material, such as for instance silicones, epoxies, polyamides, polymethacrylates or others; finally, patent US 6,819,042 B2 discloses desiccant systems consisting of a desiccant material being dispersed in a resin, for instance of polyethylene, polypropylene, polybutadiene and polyisoprene.

A first generic drawback occurring with the known sorbing systems resides in the manufacturing thereof. When moisture sorbers such as alkaline-earth metal oxides are employed, particles which are moist due to exposure to air tend to adhere to each other, this degrade their characteristics and therefore they do not have the granulometry and the homogeneous distribution which are desired in the final sorbing system any more.

Further, these systems are generally formed by suspending the particles of the sorbing material in the material which will form the matrix when it is still liquid (for example, an organic material before polymerization or^' a molten polymer); the different densities and surface energies of particles and matrix material may cause demixings in the suspension, unless the system is kept under continuous stirring, at least from the time of the formation of the suspension until the matrix reaches a viscosity being sufficient to prevent the sedimentation of the solid particles; however this represents an evident complication of the manufacturing processes for these systems. Further, systems comprising a matrix obtained by means of the above described processes, will have sorbing particles that will show a tendency to aggregate during the matrix consolidation.

In addition, when a certain sorbing system is given and it is desired to modify the sorption characteristics thereof, and in particular sorbable gases, it is necessary to provide again a new preparation by changing the nature of the sorbing particle: this generally involves the need to undertake from the beginning the study of the rheological properties of the system and of how these evolve during the manufacturing thereof, in order to ensure the achievement of a homogeneous and stable particle dispersion. Finally, as a consequence of gas sorption these systems may change their overall physical properties, and particularly the optical ones, such as the refraction index or the light radiation absorption, due to chemical-physical variations of the sorbing particles. This last point is particularly critical: in fact the getter systems of the prior art do not have optical properties that guarantee their satisfactory use in the previously mentioned TOLED screens. *

Object of the present invention is to provide gas sorbing systems which overcome the drawbacks of the prior art.

This and other objects are achieved according to the present invention by a gas sorbing system consisting of gas sorbing components dispersed in permeable dispersant means consisting of a polymeric matrix which is porous- or permeable to the gases to be sorbed, characterized in that said gas sorbing components consist of a central nucleus, which can be selected between a silica particle, a polyhedral oligomeric silsesquioxane and a spherosilicate, to which there are bound at least one organic or metalorganic radical carrying a functional group, which is able to chemically fix the gas to be sorbed, and at least one anchoring organic radical consisting of a chain of carbon atoms having the functionality of fixing the nucleus in the matrix polymer.

The anchoring organic radical is capable of keeping the nucleus in a fixed position with respect to the polymeric matrix through Van der Waals interactions, hydrogen bonds, covalent bonds or ionic interactions. The polymeric matrix can be made of any polymeric material which is permeable to the gaseous species to be sorbed; preferably this polymer exhibits adhesiveness - A -

characteristics, so as to be able to be fixed to an inner wall of the receiving device without the need to use additional adhesives.

In general, in order to achieve a permeable dispersant means, polymers and manufacturing processes thereof are preferably selected among those allowing to achieve maximum free volume of the polymeric medium, maximum order and regularity of the polymer chains, minimum cross-linking grade, minimum packing density and maximum interactions with permeant species.

Suitable polymers for the achievement of a permeable dispersant means are, for example, polyacrylates and polymethacrylates, polyetherimides (PEI), polyamides (PA), cellulose acetate (CA), cellulose triacetate (TCA), polysiloxanes (also known as silicones), polyvinyl alcohol (PVAL), polyethylene oxide (PEO), polyethylene glycol

(PEG), polypropylene glycol (PPG), polyvinylacetate (PVAC), polyethylene-vinyl alcohol copolymers, and PA-PEO and polyurethanes-PEO copolymers.

In order to achieve a high diffusion of gas towards the sorbing component the polymeric matrix of the systems of the invention may also be porous. In this specific case the suitable polymers list is very wide, because limitations bound to permeability are missing.

The gas sorbing components of the invention are formed by a central nucleus to which at least two organic radicals having different functionalities are bound, with possibly further organic radicals which give the sorbing component desired auxiliary functionalities, as detailed in the following.

The first essential functionality of the components of the invention is the gas sorption. The organic radical expressing this functionality carries a functional group being able to chemically fix the gas to be sorbed; the exact nature of the functional group depends on the gas to be sorbed. In case that the gas to be sorbed is water, the functional group can be selected among epoxy groups, (activated) double and triple bonds, organic anhydrides, linear and cyclic alkoxides, isocyanate groups, isothiocyanate groups and metalorganic groups being easily hydrolysable such as alkoxysilanes and metal alkoxides. In case that the gas to be sorbed is oxygen, functional groups can be selected among phenols, amines (preferably aromatic), thioethers, aldehydes and tertiary carbon atoms.

In case that the gas to be sorbed is CO₅ functional groups can be selected among unsaturated bonds, amino and ketone groups in the presence of lithium-based organometallic compounds. The second essential functional group of the components of the invention is an organic radical consisting of a chain of carbon atoms, which has the function of an anchoring agent in the matrix polymer as mentioned above, thus ensuring miscibility of the component within the matrix, stability of the solutions or suspensions of said component in solutions of solvents and monomers or oligomers provided prior to the polymer formation, and a uniform spatial dispersion of nuclei during the consolidation of the polymeric matrix.

The chemical nature of this chain depends on the components of the initial solutions, from which the matrix polymer is obtained. Generally, in case that the initial solutions or suspensions consist of non-polar solvents and monomers such as hydrocarbons or ethers, the chain can consist of a hydrocarbon radical; on the contrary, in the case of polar solvents and monomers such as alcohols or ketones the chain can carry polar groups such as alcoholic groups, carbonyl groups, acids, salts (e.g. salts of carboxylic acids such as the so called "fat acids"), amines or the like.

Organic radicals having a high affinity to monomers will preserve such affinity also towards the final polymeric matrix. For instance, in case that the polymer is polyvinyl alcohol or a polyamide, the radical can carry hydroxyl groups, in case that the polymer is polyethylene or polypropylene the radical consists of a hydrocarbon chain, in case, finally, that the polymer belongs to the fluoropolymer class (e.g. PTFE, PVDF, PVF, ETFE) the radical carries fluorinated groups (e.g. -CF₂-). The radical can also be bound to the polymeric matrix by means of a covalent bond. Such a bond can form during reactions of copolymerization with the organic monomer/oligomer, during cross-linking reactions of the polymeric matrix or, finally, during grafting reactions on said matrix.

In the first case, for instance, the radical carries allylic, vinyl or styrene groups which copolymerize with olefins by means of a radical-based mechanism; an example is the poly-(styryl-POSS-co-styrene) copolymer, obtained by copolymerization of styrene and polyhedral oligomeric silsesquioxanes nuclei being functionalized with styrene groups; polyhedral oligomeric silsesquioxanes, known as POSS^® (POSS^® is a Hybrid Plastics LLP company's trademark), are more widely described in the following; another possible nucleus can be chosen in the class of spherosilicates. The radical can also be bound to the polymeric matrix thanks to cross-linking reactions. For instance, by irradiating with ultraviolet radiation a mixture comprising a nucleus having a radical with one or more methacrylic groups, an acrylic resin and a photoinitiator which is sensitive to said radiation, the unsaturated groups of the radical react with the resin thus giving rise to a highly cross-linked polymeric matrix, in which the radical is bound to the dispersant by means Of₁ covalent bonds C-C.

Matrix-radicals covalent bonds can be formed also through grafting reactions which occur by means of radical initiators in solution (where polymer and nuclei are dissolved) or in dry conditions (nuclei and initiator are added to the polymer powder without adding solvents). Finally, the dispersant polymer matrix may also be formed by a reaction between anchoring chains located on different nuclei, without the need of a further dispersant polymer. For instance the methacrylates POSS^® can polymerize through a radical-based mechanism, thus forming the matrix.

Radicals of the two above described types are linked to a central nucleus which can be selected between a silica particle, a polyhedral oligomeric silsesquioxane and a spherosilicate. The dimensions of the central nucleus can range between about 10 A and 100 μm, preferably said dimension is comprised between 100 A and 10 μm.

Silica particles forming a first possible type of nuclei of the invention are generally obtained by reaction in the gaseous state between oxygen and silicon compounds such as SiCl₄, Si(O-CH₃)₄ or Si(O-CH₂-CH₃)₄; from this reaction SiO₂ particles are obtained having a size in the order of tens of Angstrom which aggregate by electrostatic interaction thus forming larger size particles. Upon first exposure to (moist) air, these particles are completely covered on the surface by hydroxyl groups -OH. The bond of gas sorbing organic radicals and anchoring agents on this type of nucleus takes place by using the presence of these -OH groups, with reactions such as:

≡Si-OH + HO-R-X → ≡Si-O-R-X + H₂O (I) wherein the ≡≡symbol indicates the three bonds of silicon with other atoms of the silica particle, while X indicates the gas sorbing group in case that R is the radical having this functionality, or simply a hydrogen atom hi case it is the anchoring radical.

The second type of nucleus of sorbing components of the invention are polyhedral oligomeric silsesquioxane molecules, known in chemistry with the POSS^® abbreviation; the base structure of these molecules consists of eight silicon atoms located at the vertexes of a cube, wherein each silicon atom is linked to three other silicon atoms by oxygen bridges, while the fourth valency of each silicon is saturated by an organic radical; this general structure can undergo modifications, for instance by opening one or two oxygen bridges and adding further organic radicals in the so formed unsaturated position. Simple and substituted POSS^® and processes for the manufacturing thereof are disclosed, for instance, in the patent applications EP 1208105, WO 01/46295 and EP 1268635; in this case the gas sorbing radical and the surfactant radical are directly bound to one of the silicon atoms; these molecules are sold by the Hybrid Plastics LLP . company in Hattiesburg, Massachussets (US).

The third type of nucleus of sorbing components of the invention are the spherosilicates, having chemical structure is [ROSiO_3/2]_n, wherein each silicon atom is linked to three other silicon atoms by oxygen bridges and to a further oxygen atom whose other bond is saturated with an organic group. Process for the manufacturing and functionalisation of spherosilicates are disclosed for instance in Agaskar P.A., Inorg. Chem., 1990, 29, 1603 and in Agaskar P.A., Symposium on the colloidal chemistry of silica, 1992, vol. 63, n.1-2, pp. 131-138.

Other functionalities which can be added to the nucleus of the sorbing components of the invention are, for example, gas sorption catalysts and chains which, in case that the gas to be sorbed is water, enhance its transport towards the nucleus.

In the case of catalysts, one or more groups having such functionality may be added by bonding it to the nucleus in the same ways previously described. Further, the radical carrying the catalytic functionality will preferably be bound to the nucleus in a position close to the radical carrying the gas sorbing group; this condition guarantees the proximity between the two functions, which is necessary for the catalyst to effectively perform the function of enhancing the reaction of addition of the gaseous molecules to the sorbing functional group; in this way the catalyst efficiency (that is the rate and the selectivity of the sorption catalytic reaction) is maximized, which is a result that would not occur if the two functionalities were present on disconnected molecules within the matrix, and thus their mutual proximity were dependant in a statistic way on their distribution within the same matrix. In case that the gas to be sorbed is water, possible catalysts are Broensted acid groups, for instance the -SO3H group or the acid catalyst being traded with the name Nafion^® (Du Pont company's trademark) or Lewis acid groups such as a -BR₂ group, where R = H, C_nH_2n+ι. Alternatively, in the case of silica nuclei, the catalyst can be impregnated on the same nucleus; in this case it is possible to use e.g. salts such as some metal halides (SnCl₄, FeCl₃, TiCl₄).

The other auxiliary functionality that cambe added to the sorbing component is that of transporting H₂O molecules towards the sorbing component (when the gas to be sorbed is water). The accessibility of the gas to be removed to the sorbing component is in fact determined by the transport thereof within the matrix, that is by the gas diffusion coefficient at a given temperature. Such a coefficient, which in the case of the permeable matrixes of the system of the invention is a high one, ensures a good net gas flow reaching the sorbing component; this flow, however, can be increased by concentrating and orienting the same preferably towards the nucleus. This can be achieved by one or more chains exhibiting high affinity to the specific gas, being chemically connected to the nucleus and immersed within the matrix. For example in the case of water it is possible to use a permeable matrix of polysiloxane and increase the net flow reaching the silica nucleus or the POSS^®, by functionalizing these latter with one or more oligoglycols or oligoethers.

In a preferred embodiment, the getter systems of the invention have the further property of being transparent to visible radiation, as previously described; in this way, the systems of the invention prove to be suitable for the application in the TOLED type screens previously mentioned.

In this specific case the dispersant medium is amorphous, while the dispersed nuclei in the polymeric matrix are nanostructured, having a size in the order of about 200 nanometers or lower. The reason for the first of these two additional requirements is that the polymers are transparent only if perfectly crystalline or completely amorphous: as it is essentially impossible to obtain perfectly crystalline polymers, above all in the case of the present invention where a powder has to be dispersed in the medium, it is necessary to use completely amorphous polymers. The second requirement derives from the fact that particles of a size being smaller than a half of the shorter visible radiation wavelength (about 400 run) do not give rise to interaction therewith, and thus do not alter the transparency of the dispersant medium; preferably the particles have a size lower than about 100 nm.

In order to meet the first requirement it is possible to use, for example, the previously mentioned permeable polyacrylates and polymethacrylates, polyetherimides (PEI), polyamides (PA), cellulose acetate (CA), cellulose triacetate (TCA), polysiloxanes (also known as silicones), polyvinyl alcohol (PVAL), polyethylene oxide (PEO), polyethylene glycol (PEG), polypropylene glycol (PPG)₃ polyvinylacetate (PVAC), polyethylene-vinyl alcohol copolymers, and PA-PEO and polyurethanes-PEO copolymers, obtained by manufacturing processes being suitable to ensure an amorphous structure.

In case that a nanoporous polymeric matrix is selected and it has to be transparent, the size of the pores should be smaller than 100 nm, preferably smaller than 80 nm.

In a second aspect thereof, the invention relates to methods of manufacturing the systems which have until now been described. The systems of the invention can be manufactured by forming suspensions of the nuclei in the dispersant medium, if this has a sufficiently low viscosity. As an alternative, it is possible to prepare a suspension of the nuclei in a solvent wherein it is possible to solubilize also the polymer forming the dispersant medium. Suitable solvents depend on the selected polymer, and are well known in organic chemistry; examples of solvents are chloroform, acetone, tetrahydrofuran and toluene for polyacrylates and polymethacrylates; formic acid and N-methylpyrrolidone for polyamides; heptane or toluene diethyl ether for polydimethylsiloxane. As an alternative, it is possible to form a suspension between the nuclei and the polymer precursors (e.g. oligomers or monomers which will form the polymer) and cause the in-situ polymer formation, for example by irradiating with UV . radiation. Alternatively it is possible to form a suspension of the nuclei which have polymerized among themselves through the anchoring chains or which are still to be

1 polymerized (in this case the final polymeric matrix coincides with such anchoring chains after they have mutually reacted); also in this last case the formation of the dispersant matrix can occur in-situ, for instance by irradiating with UV radiation. The initial solution (if this contains the polymer that provides the dispersant medium or the precursors thereof), or the low-viscosity polymer having already the nuclei therein, can be poured in suitable molds, or can be deposited on an inner surface of the final housing (e.g. an OLED screen) for instance by serigraphy or by common techniques particularly in the microelectronics industry and known as spin-coating, dip-coating, spray-coating or ink-jet printing. The mixture can be caused to "solidify" (in this case referring to a "solid" as an extremely high-viscosity material, such as to keep a given shape) by extracting the solvent, by on site polymerization, or if the low viscosity was ensured by the fact of maintaining the polymer in a molten state, by cooling.

In case that it is desired to obtain a nanoporous matrix it is possible to use one of the techniques which are commonly employed such as employing so-called porogen agents (e.g. highly branched molecules such as the ester of the benzenetricarboxylic and of the polyethylene glycol, known in the field with the acronym BTRC-PEG, which decompose thermally thus generating porosity in the matrix) or the so-called polymer phase separation; in the latter technique the nuclei and the polymer which is used for creating the dispersant matrix are mixed with a second polymer, the mixture is deposited on a substrate (e.g. by spin coating) and the_. obtained layer is subsequently treated with a solvent being selective to the second polymer, which dissolves this latter thus creating a porous structure. If the molecular weights of the initial polymers are suitably selected it is possible to obtain a nanoporous structure.

Claims

1. Gas sorbing system formed by gas sorbing components which are dispersed in a polymeric matrix being porous or permeable to the gases to be sorbed, characterized in that said gas sorbing components consist of a central nucleus, which can be selected between a silica particle, a polyhedral oligomeric silsesquioxane and a spherosilicate, to which there are bound at least one organic or metalorganic radical carrying a functional group which is able to chemically fix the gas to be sorbed, and at least one anchoring organic radical consisting of a chain of carbon atoms which has the functionality of fixing the nucleus in the matrix polymer,

2. System according to claim 1 for water sorption, wherein the functional group is selected among epoxies, activated double and triple bonds, organic anhydrides, linear and cyclic alkoxides, isocyanate, isothiocyanate and metalorganic groups being easily hydrolysable. 3. System according to claim 1 for oxygen sorption, wherein the functional group is selected among phenols, amines, thioethers, aldehydes and tertiary carbon atoms.

4. System according to claim 1 for carbon monoxide sorption, wherein the functional group is selected among unsaturated bonds, amino and ketone groups in the presence of organornetallic compounds containing lithium.

5. System according to claim 1 wherein the polymeric matrix consists of a material selected between hydrocarbons and ethers and the anchoring radical is hydrocarbon-based.

6. System according to claim 1 wherein the polymeric matrix consists of a material selected among alcohols, ketones or amides and the anchoring radical carries a substituent selected among alcoholic groups, carbonylic groups, acids, salts and amines.

7. System according to claim 1 wherein the polymeric matrix consists of a fluoropolymer and the anchoring radical carries fluorinated groups.

8. System according to claim 1 wherein the anchoring radical is bound to said polymeric matrix by a covalent bond.

9. System according to claim 8 wherein said, covalent bond is formed by a copolymerization reaction between the anchoring radical and an organic monomer/oligomer.

10. System according to claim 9 wherein said covalent bond is formed by a copolymerization reaction between olefins and an anchoring radical which carries allylic, vinyl or styrene groups.

11. System according to claim 10 wherein said covalent bond is formed by copolymerization between polystyrene and the molecules known as POSS^®.

12. System according to claim 10 wherein said covalent bond is formed by copolymerization between polystyrene and a spherosilicate. 13. System according to claim 8 wherein said covalent bond is formed by a cross-linking reaction of the polymeric matrix.

14. System according to claim 13 wherein said cross-linking reaction is carried out by irradiating with ultraviolet radiation a mixture comprising a nucleus which has a radical with one or more methacrylic groups, an acrylic resin and a photoinitiator being sensitive to said radiation.

15. System according to claim 8 wherein said covalent bond is formed by a reaction of grafting on said matrix.

16. System according to claim 15 wherein said grafting reaction is carried out by radical-based initiators in a solution where the matrix polymer and the molecules of the anchoring radical are dissolved.

17. System according to claim 15 wherein said grafting reaction is carried out in dry conditions, in a mixture containing molecules of the anchoring radical, polymer powder and radical-based initiators of said reaction.

18. System according to claim 8 wherein the polymeric matrix is formed by polymerization among anchoring chains positioned on different nuclei.

19. System according to claim 1 wherein |he size of said nucleus ranges from 10 A to 1 μm.

20. System according to claim 1, wherein also substituents which carry gas sorption catalyzing groups are bound to said nucleus. 21. System according to claim 20 wherein, when the gas to be sorbed is water, said catalyst groups are selected between Broensted or Lewis acids. ^•22. System according to claim 21 wherein said Broensted acid is selected between the -SO₃H group or Nation.

23. System according to claim 21 wherein said Lewis acid is a -BR₂ group, where R = H, C_nH_2lVH. 24. System according to claim 21 wherein, when the nucleus is a silica particle, the catalyst is a metal halide being impregnated o said nucleus.

25. System according to claim 2 or 2Ij, wherein to said nucleus are further bound chains enhancing the transport of water molecules to the nucleus.

26. System according to claim 25, wherein said chains enhancing the transport of water molecules to the nucleus are selected between oligo glycols or oligoethers.

27. System according to claim 1, which is gas sorbing and transparent to visible radiation, wherein the polymeric matrix is formed of a completely amorphous polymer and the size of the nuclei is not larger than about 200 nanometers.

28. System according to claim 27, wherein said amorphous polymer is selected among polyacrylates, polymethacrylates, polyetherimides, polyamides, cellulose acetate and triacetate, polysiloxanes, polyvinyl alcohol, polyethylene oxide, polyethylene glycol, polypropylene glycol, polyvinylacetate, polyethylene-vinyl alcohol copolymers, and polyamides-polyethylene oxide copolymers and polyurethanes-polyethylene oxide copolymers. 29. System according to claim 28, wherein said matrix is nanoporous, the size of pores being smaller than 100 nanometers.

30. Method of manufacturing a system of claim 1, consisting in preparing a suspension of said gas sorbing components and the matrix polymer or the precursors thereof in a solvent, and subsequently extracting the solvent 31. Method of manufacturing a system of claim 30, wherein said solvent extraction is carried out after the suspension polymerization of the polymer precursors.

32. Method of manufacturing a system of claim 1, consisting in preparing a suspension of said sorbing components in the polymer or in the precursors thereof, being kept in liquid phase by heating, and subsequently causing the suspension to solidify by cooling.

33. Method of manufacturing a system of claim 32 wherein said solidification by cooling is carried out after the polymerization pf the polymer precursors.

34. Method of manufacturing a system of claim 1, consisting in preparing a suspension of said sorbing components in the polymer precursors and causing said precursors to polymerize by irradiating by means of UV radiation.

35. Method of manufacturing a system of claim 1, consisting in causing the anchoring radicals of said sorbing components to polymerize among themselves.