Methods for improving the airtightness of buildings using biopolymer-based membranes

Abstract

The present invention relates to a method for improving the airtightness of a building or a room in a building, comprising the use of a vapor barrier membrane on the inner surface of a wall of the building or a room in a building, characterized in that the vapor barrier membrane is a humidity regulating membrane having an active portion, The active part is an intermediate layer having a thickness of 2 μm to 200 μm, preferably 4 μm to 100 μm, and a water vapor permeability coefficient P 1 The biopolymer has a water vapor permeability coefficient P 1 increases with average relative humidity and is at least 600 Barrer when measured at 23°C and an average relative humidity of 25.5%; and on either side of, and preferably in contact with, the intermediate layer; - two outer layers having a thickness between 100 nm and 20 μm, preferably between 200 nm and 2.5 μm, and independently of each other having a water vapor permeability coefficient P 2 The organic polymer has a water vapor permeability coefficient P 2 two outer layers, each of which has a resistance of 105 to 550 Barrer, preferably 110 to 520 Barrer, and in particular 120 to 500 Barrer, when measured at 23° C. and an average relative humidity of 25.5%; The present invention relates to a method comprising the steps of:

Description

[Technical field]

[0001] The present invention relates to a method for improving the airtightness of a building or a room within a building using a vapour barrier membrane having a hydrophilic intermediate layer based on a biopolymer and two outer layers which are relatively more hydrophobic than the intermediate layer. [Background technology]

[0002] Humidity regulators or humidity-regulating vapor barrier membranes whose water vapor permeability varies depending on the humidity of the air have been known for many years. For reasons explained, for example, in WO 96 / 33321, there is a need to obtain membranes that allow water vapor to pass easily at high relative humidity (RH) (70%-100% RH) and effectively block water vapor at low relative humidity (50% RH or less).

[0003] Such membranes, if they are arranged on the inner surface of the thermal insulation (the surface facing the interior of the building or room), prevent as much as possible during the cold and dry seasons water vapor from penetrating from the interior of the building into the space between the membrane and the wall and condensing on the wall (cold wall). Conversely, in hot seasons, the high permeability of the membrane allows moisture potentially present in the structural elements of the frame to escape towards the inside of the building. This property is important in particular in the case of new constructions, i.e. when installed, where certain elements may have a very high moisture content due to their storage conditions, but also in the case of water penetration into existing structures. In any case, it is important that the entire structure can be dried in an effective manner in summer towards the outside and towards the inside of the building. This need is particularly important when the elements constituting the system are those which encourage the growth of microorganisms.

[0004] Such vapor barrier membranes have differentiated behavior as a function of their surrounding relative humidity conditions and are often referred to as "smart vapor retarder" (SVR) membranes. In this application, the terms "humidity regulator," "humidity regulation," and "smart" are used synonymously when they describe changes in the water vapor permeability of a vapor barrier membrane.

[0005] The water vapor permeability of a membrane is usually expressed as the "equivalent air layer thickness" (Sd) for the diffusion of water vapor. This thickness is expressed in meters and corresponds to the thickness of the air layer that would oppose an equivalent resistance to the diffusion of water vapor. The greater the equivalent air layer thickness, the less permeable the membrane is to water vapor. The equivalent air layer thickness (Sd) can be determined according to standards EN 1931 and EN ISO 12572.

[0006] Humidity control vapor membranes are generally considered to be even more beneficial and effective because their equivalent air thickness is higher when the relative humidity is low and lower when the relative humidity is high.

[0007] Commercially available humidity regulating vapor barrier membranes described in the state of the art are generally based on synthetic organic polymers made from petroleum monomers.

[0008] The most frequently mentioned and used polymers are polyamides, especially polycaprolactam, polyvinyl alcohol (PVOH), copolymers of ethylene and vinyl acetate and / or vinyl alcohol (EVA and EVOH). The most hydrophilic polymers (PVOH, EVOH) may be combined in multilayer structures with thin layers that are more hydrophobic, especially those based on polyolefins, such as polyethylene, polypropylene and copolymers of ethylene and propylene.

[0009] Examples of documents describing such "smart" vapour barrier membranes include WO 2007 / 010388, WO 2006 / 034381, WO 2005 / 110892, US Pat. No. 7,008,890, US Pat. No. 6,808,772 and US Pat. No. 6,878,455.

[0010] The aim of the research that led to the present invention was to replace the humidity regulating vapor barrier membranes of the prior art, which are generally based on non-biodegradable petroleum-derived polymers, with humidity regulating vapor barrier membranes based on bio-based and / or biodegradable polymers. These bio-based and / or biodegradable polymers are hereinafter referred to as "biopolymers". The biopolymers are preferably based on bio-based, i.e. short-term renewable biological materials. In a particularly preferred embodiment, the biopolymers used in the membranes of the present application are both bio-based and biodegradable.

[0011] Biopolymers derived from living organisms include both natural organic polymers present as such in biomass, organic polymers obtained by physical and / or chemical modification of these natural polymers, and synthetic organic polymers obtained by polymerization of biologically derived components.

[0012] Such membranes based on biopolymers, for example based on cellulose, chitosan or even poly(3-hydroxybutyrate) (PHB), are known and are used as an alternative to films based on synthetic polymers of petroleum origin, in particular in the field of food packaging. In this field, the membranes are generally required to provide a water vapor permeability that is relatively independent of humidity and temperature conditions. Furthermore, in the field of food packaging, the service life of packaging films is rather limited, generally ranging from a few days to a few weeks, at most a few months. In the field of vapor barrier membranes, on the contrary, a long service life of at least several years or even decades is required.

[0013] Membranes based on biopolymers are often hydrophilic to some extent, which makes their permeability to water vapor high. The equivalent air layer thickness of these membranes is generally less than 1 m, and its absolute value changes very little with the relative humidity of the atmosphere surrounding them. Thus, these membranes maintain an extremely high permeability to water vapor, regardless of the surrounding conditions.

[0014] Without wishing to be bound by any theory, it is believed that the low variation in water vapor transmission rate of these somewhat hydrophilic membranes can be attributed to the plasticizing effect of water "dissolving" in the membrane, even at low humidity: the higher the ambient humidity, the more the membrane material is plasticized by water, making it easier for water molecules to diffuse in the membrane.

[0015] Thus, the main drawback of these membranes made of biopolymers, for their possible use as humidity control vapor barriers, lies in the fact that they cannot function satisfactorily during the cold and dry seasons, since their permeability to water vapor remains generally too high at low relative humidity.Thus, a membrane made only of cellulose would not be able to form a sufficient barrier against water vapor penetrating from inside the building and would not be able to effectively enough prevent water vapor from penetrating the space between the membrane and the wall and condensing in the insulation and on the inner surface of the exterior wall. Summary of the Invention [Problem to be solved by the invention]

[0016] In summary, hydrophilic membranes based on biopolymers used in the field of food packaging remain too permeable to water vapor under conditions of low relative humidity (cold seasons). Therefore, they are not "smart" enough to function adequately as vapor barriers in the field of thermal insulation of buildings, especially for improving airtightness and management of water vapor flow in buildings. [Means for solving the problem]

[0017] The present invention is based on the surprising discovery that it is possible to very significantly increase the "smartness" of membranes based on biopolymers, thus making them suitable for use as vapour barrier membranes in the building sector, by applying a very thin layer of polyester with low water vapour permeability on each of their two faces.

[0018] This finding was even more surprising considering that the highly hydrophobic polyesters deposited on both sides of the biopolymer membrane have a water vapor permeability that is independent of the relative humidity of the surroundings. In other words, a membrane consisting only of these hydrophobic polymers would have no humidity regulation. It was therefore impossible to predict that depositing these same hydrophobic polyesters on the face of a membrane made of one or more hydrophilic biopolymers would significantly improve its "smartness" by allowing it to have a very low water vapor permeability in dry periods and a high water vapor permeability in wet periods. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Accordingly, the present application relates to a humidity regulating vapor barrier membrane having an active portion, The active part is: an intermediate layer having a thickness between 2 μm and 200 μm, preferably between 4 μm and 100 μm, and made of a biopolymer having a water vapor permeability coefficient P1, which increases with the average relative humidity and is at least 600 Barrer, determined at 23° C. and an average relative humidity of 25.5%; and on both sides of, and preferably in contact with, the intermediate layer; - two outer layers having a thickness of 100 nm to 20 μm, preferably 200 nm to 2.5 μm, and consisting, independently of one another, of an organic polymer having a water vapour permeability coefficient P2 of 105 to 550 Barrer, preferably 110 to 520 Barrer, in particular 120 to 500 Barrer, determined at 23° C. and an average relative humidity of 25.5%, has.

[0020] It also relates to a method for improving the airtightness of a building or a room in a building, comprising using a vapor barrier membrane on the inner surface of a wall of said building or said room in a building, characterized in that the vapor barrier membrane is a humidity regulating vapor barrier membrane having an active portion, The active part is: an intermediate layer having a thickness between 2 μm and 200 μm, preferably between 4 μm and 100 μm, and made of a biopolymer having a water vapor permeability coefficient P1, which increases with the average relative humidity and is at least 600 Barrer, determined at 23° C. and an average relative humidity of 25.5%; and on both sides of, and preferably in contact with, the intermediate layer; - two outer layers having a thickness of 100 nm to 20 μm, preferably 200 nm to 2.5 μm, and consisting, independently of one another, of an organic polymer having a water vapour permeability coefficient P2 of 105 to 550 Barrer, preferably 110 to 520 Barrer, in particular 120 to 500 Barrer, determined at 23° C. and an average relative humidity of 25.5%, has.

[0021] The active part of the membrane is preferably a three-layer structure, made up of a middle layer and two outer layers, as defined above.

[0022] The permeability coefficients P1 and P2 are those of the polymers forming the middle and outer layers, respectively. They correspond to the ratio of the water vapor mass flow rate (Q) through an area (A) of a membrane of the polymer being tested having a given thickness (E) under the effect of a water vapor pressure difference (dP) existing on both sides of the membrane.

[0023]

number

[0024] They are measured according to the experimental protocol detailed below and are expressed in "Barrer", i.e., mass flow rate Q is expressed in cm per second. 3 (at normal pressure and temperature), the thickness E is expressed in cm, and the area A of the traversed region is expressed in cm 2 and the water vapor pressure difference (dP) is expressed in cmHg (see especially SAStern, Journal of Polymer Science Part A-2, vol. 6 (1968), pages 1933-1934).

[0025] Thus, the membrane of the invention comprises a relatively thick layer based on a hydrophilic biopolymer (the middle layer), which is coated on both sides with a continuous layer of a hydrophobic polymer (the outer layer).

[0026] The two outer layers generally have a thickness smaller than that of the intermediate layer, the ratio of the thickness of the intermediate layer to the thickness of each outer layer being advantageously between 1.5 / 1 and 1000 / 1, preferably between 2 / 1 and 500 / 1, in particular between 3 / 1 and 200 / 1.

[0027] The two outer layers are preferably in direct contact with the middle layer, ie, the interface between the layers is preferably free of adhesive.

[0028] In a less preferred embodiment, the outer layer is adhered to the intermediate layer by an adhesive, which will preferably have a permeability coefficient P3 greater than the permeability coefficients P1 and P2. In other words, the adhesive should not offer a resistance to the diffusion of water vapor greater than the resistance from each of the layers that make up the membrane.

[0029] The layers defined above form the "active part" of the membrane of the invention, which is preferably a membrane obtained in a known manner by coextrusion of the thermoplastic polymers forming the different layers, by thermal bonding of a film (outer layer) onto an intermediate layer or by depositing a coating on both sides of the intermediate layer.

[0030] The active part has in principle a mechanical strength that allows it to be used alone, i.e. without a support layer, but especially for active layers of small thickness (less than 50 μm), it may be advantageous to reinforce it with an air-permeable mechanical structure, the resistance of which to the diffusion of water vapor is therefore negligible compared to the resistance of the active layer, which is air-impermeable.

[0031] Thus, in an advantageous embodiment, the vapor barrier membrane further comprises an air-permeable reinforcing or protective layer, which is in direct contact with the active part, i.e. one of the outer layers. This support layer may be an air-permeable grid, a perforated plate, an open-pore foam or a woven or nonwoven fabric. It is preferably an air-permeable fabric, preferably a nonwoven fabric. Examples of particularly preferred support layers may include nonwoven fabrics made of polypropylene or polyester fibers or of glass fibers. The support layer or layers are preferably attached to the active membrane or layer by gluing with a polyurethane adhesive. The invention also encompasses membranes in which a reinforcing structure, such as a grid or a nonwoven fabric, is incorporated in the active part of the membrane, in particular in the intermediate layer.

[0032] As explained at the beginning, the biopolymers forming the intermediate layer are biologically derived and / or biodegradable organic polymers. They are preferably biologically derived.

[0033] The biologically derived biopolymer is preferably selected from the group consisting of: - Osides, - proteins, and - Synthetic polymers derived from biological monomers.

[0034] Osides include heterosides, the hydrolysis of which produces non-sugar compounds, and holosides, which are polymers composed only of sugars.

[0035] Examples of osides that may be used to form the intermediate layer of the vapor barrier of the present invention may include those selected from the group consisting of alginic acid, carrageenan, cellulose, especially regenerated cellulose (cellulose hydrate), chitin, chitosan, pectin, dextrin, starch, curdlan, FucoPol, gellan gum, pullulan and xanthan.

[0036] The protein is advantageously selected from the group consisting of gluten, isolated soy protein, zein, whey protein, casein, collagen and gelatin.

[0037] Most of these bio-based polymers, extracted from biomass, have a high affinity for water and dissolve or swell in water to form hydrogels.

[0038] As a result, it may be advantageous or necessary to chemically modify them to reduce their hydrophilicity, and in particular to crosslink them to render them insoluble in water.

[0039] Examples of chemically modified biologically derived biopolymers include cellulose esters, especially cellulose acetate, cellulose ethers (especially ethyl cellulose, hydroxyethyl cellulose), nitrocellulose, starch esters and ethers.

[0040] The third category of biologically derived biopolymers is formed by polymers synthesized from biologically derived monomers.

[0041] These polymers may be linear or branched and therefore thermoplastic or thermosetting.

[0042] As examples of synthetic polymers obtained from biologically derived monomers, mention may be made of those selected from the group consisting of polyhydroxyalkanoates (PHAs), in particular polyhydroxybutyrate (PHB) and poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV), polylactic acid (PLA), polyglycolic acid (PGA), poly(lactide-co-glycolide) (PLGA), polymers obtained by polymerization of lipid monomers, and thermosetting polymers obtained by reaction of monosaccharides, disaccharides, oligosaccharides and / or alditols with polycarboxylic acids and / or polyaldehydes.

[0043] Thermosetting polymers obtainable by reaction of mono-, di-, oligosaccharides and / or alditols with polycarboxylic acids and / or polyaldehydes are well known in the field of mineral wool binders and are described in detail, for example, in WO 2009 / 080938, WO 2010 / 029266, WO 2013 / 014399, WO 2013 / 021112 and WO 2015 / 132518 in the name of the Applicant.

[0044] As explained at the beginning, polymers of petrochemical origin may also be used to form the intermediate layer of the membrane of the invention, when they are biodegradable within the meaning of the NF EN 13432 standard.

[0045] The biodegradable biopolymer may advantageously be selected from the group consisting of homopolymer aliphatic polyesters, such as poly(caprolactone) (PCL) and poly(butylene succinate) (PBS), aliphatic copolyesters, such as poly(butylene succinate-co-adipate), aromatic copolyesters, such as poly(butylene adipate-co-terephthalate) (PBAT), and polyesteramides.

[0046] All biopolymers constituting the intermediate layer have a permeability coefficient P1, measured under dry conditions (average relative humidity of about 25%) at 23° C., of 600 Barrer or more, preferably 600 to 50,000 Barrer, in particular 700 to 30,000 Barrer, ideally 800 to 20,000 Barrer.

[0047] This permeability coefficient is measured as follows:

[0048] Five samples of the same membrane with thickness (E) are sealed with a sealing product on top of a test cup containing a desiccant (CaCl2 powder with a relative humidity of about 1% in the test cup). A template is placed on the surface of the film before applying the sealing product to form an exchange zone of a defined zone (A) free of sealing product. Various sealing products may be used. The sealing product is for example a mixture of 60% microcrystalline wax and 40% refined crystalline paraffin.

[0049] The cups thus produced are placed in a temperature-controlled test chamber at temperature (23° C.) and relative humidity (50%), also called a climatic chamber.

[0050] Due to the difference in partial vapor pressure (dP) between inside the test cup and in the chamber, water vapor migrates through the exchange zone of the membrane. Periodic weighing of the cup is carried out to measure the water vapor transmission rate (Q) at steady state and, by calculation, the water vapor permeability coefficient of the considered film, expressed in Barrer. The average of the measured permeabilities on the different assemblies is then calculated, corresponding to the aforementioned permeability coefficient P1.

[0051] The hydrophilic intermediate layer of the vapor barrier membrane of the invention is covered on both sides with a continuous layer of an organic polymer that is more hydrophobic and less water vapor permeable than the intermediate layer. Here, the term "continuous" means that each outer layer completely covers one side of the central membrane, so that the latter is not in contact with the surrounding atmosphere. The two continuous layers may be of the same chemical nature and may be of the same thickness, or may be of different chemical natures and / or different thicknesses. Each layer is preferably in direct contact with the intermediate layer.

[0052] The permeability coefficient P2 of each outer layer is 105 to 550 Barrer, preferably 110 to 520 Barrer, and particularly preferably 120 to 500 Barrer. The permeability coefficient is measured in the same manner as the coefficient P1.

[0053] The organic polymers constituting the outer layer are advantageously selected from the group consisting of semi-aromatic polyesters obtained by polycondensation of aliphatic polyols with aromatic polyacids. The semi-aromatic polyesters are preferably thermoplastic polyesters obtained by polycondensation of aliphatic diols, such as ethylene glycol, propane-1,3-diol and butylene glycol, with aromatic diacids, such as terephthalic acid and naphthalic acid. They are preferably selected from the group consisting of poly(ethylene terephthalate) (PET), polybutylene terephthalate (PBT), poly(trimethylene terephthalate) (PTT) and poly(ethylene naphthalate) (PNE), and the corresponding copolyesters.

[0054] The permeability coefficient P2 of aromatic polyesters decreases when the crystallinity and therefore the orientation of the polyester chains increases. However, it generally remains within the above range. Thus, P2 can be adjusted as required by modifying the orientation of the chains in the polyester layer.

[0055] A vapor barrier membrane having an intermediate layer made of cellulose, in particular regenerated cellulose, and two outer layers composed of a semi-aromatic polyester, preferably poly(ethylene terephthalate), is a particularly preferred embodiment of the vapor barrier membrane used in the method of the present invention.

[0056] The active part of the vapour barrier membrane used in the method of the invention advantageously has a thickness of 5.0 μm to 240 μm, preferably 10 μm to 120 μm and in particular 15 μm to 80 μm, these values ​​corresponding to the active part of the membrane (3 layers) but not including possible reinforcing and / or protective structures.

[0057] Preferably, the wall of the room or building whose airtightness is to be improved is insulated, i.e. covered, by a thermal barrier material, and the vapor barrier membrane is attached to or integrated into the thermal barrier material. In one embodiment of the method for improving the airtightness of a building or a room in a building, the vapor barrier membrane of the present invention is then attached to a position internal to the thermal barrier material, preferably in direct contact therewith. This attachment may be by any suitable means that does not significantly reduce the airtightness of the membrane. For example, it may be by gluing, stapling, or a mechanical fastening system, which may use hooks and woven loops (Velcro® type hook-and-loop fasteners).

[0058] In another embodiment of the method of the present invention, the vapor barrier membrane is integrated into the insulation and attached to the wall of the room or building at the same time as the insulation, in which case the membrane is oriented parallel to the two main surfaces of the insulation and is preferably positioned closer to the main surface facing the interior of the room or building than to the main surface facing the wall.

[0059] The thermal barrier may be any water vapor permeable barrier, including among others foams and fiber-based materials. It is preferably made of mineral fibers (mineral wool) or natural organic fibers (lignocellulosic fibers, cellulose cotton, animal wool), synthetic fibers (polyester fibers) or man-made fibers. It is preferably made of mineral wool. EXAMPLES

[0060] The four vapor barrier membranes were subjected to evaluation of their water vapor permeability under wet and dry conditions.

[0061] For this, each membrane is placed to close an aluminum cup using molten paraffin wax (a mixture of 60% microcrystalline wax and 40% refined crystalline paraffin) as a binding product, thereby ensuring a tight seal. To measure the water vapor transmission rate in dry conditions, calcium chloride is introduced into the cup before sealing it with the membrane, resulting in an internal relative humidity of about 1%. The cup / membrane assembly is then introduced into a climatic chamber with a relative humidity of 50% and a temperature of 23°C, so as to generate a water vapor differential pressure (dP) on both sides of the membrane. The flow rate (Q) of water vapor through a zone (A) of a membrane with a thickness (E) is measured by weighing the cup over time, and the permeability coefficient (expressed in Barrer) is calculated using the following formula:

[0062]

number

[0063] The permeability coefficient P1 calculated in this way corresponds to an average relative humidity of 25.5% ((1%+50%) / 2).

[0064] When measuring water vapor transmission rate under humid conditions (average relative humidity 90%), the procedure is similar, except that liquid water is introduced into the cup to set the relative humidity to 100% and the relative humidity in the climate chamber is set to 80%.

[0065] The equivalent air layer thickness (Sd) is also determined for each membrane according to standard EN ISO12572.

[0066] The first membrane is a vapor barrier membrane according to the invention. It consists of an intermediate layer of cellulose with a thickness of 21.4 μm sandwiched between two layers of polyethylene terephthalate (PET) with a thickness of 800 nm each. The permeability coefficient P1 of the intermediate layer of cellulose is 5600 Barrer at 25.5% relative humidity (23° C.) and 34600 Barrer at 90% relative humidity (23° C.); the permeability coefficient P2 of the PET layer is 300 Barrer (23° C.). It does not vary significantly with relative humidity.

[0067] The second and third membranes consist only of cellulose and have the same permeability coefficient P1 as the middle layer of the first membrane.

[0068] The fourth membrane is a membrane made of a single active layer of polyamide 6 having a thickness of 40 μm, attached to a polypropylene nonwoven fabric, and is commercially available under the name Vario KM Duplex™ (Saint-Gobain Isover).

[0069] The technical properties of the membrane (layer composition, thickness, equivalent air layer thickness under dry and humid conditions) are summarized in Table 1 below.

[0070] [Table 1]

[0071] It can be seen that the difference in equivalent air layer thickness under dry and wet conditions for the three-layer vapor barrier membrane according to the invention (Membrane 1) is significantly stronger than that for all comparative membranes (Membranes 2 to 4).

[0072] The two cellulose membranes (Membranes 2 and 3) have an equivalent air layer thickness (S d ) due to their insufficient moisture regulation they are not suitable as vapor barrier membranes. During dry and cold seasons such membranes would allow too much water to pass into the space between the membrane and the building wall. This insufficiently "smart" behavior is nicely improved by the presence of two thin PET layers.

[0073] It should also be noted that the membrane according to the invention (Membrane 1) has a much lower total thickness (23 μm) than the thickness of the active part of the membrane sold by the Applicant, which is equal to 40 μm (VScenario KM Duplex™). The superior performance of the membrane according to the invention results in a reduction in raw materials and therefore in costs.

Claims

1. A method for improving the airtightness of a building or a room in a building, comprising the use of a vapor barrier membrane on an inner surface of a wall of the building or the room in the building, characterized in that the vapor barrier membrane is a humidity regulating membrane having an active portion, The active moiety is an intermediate layer having a thickness between 2 μm and 200 μm, preferably between 4 μm and 100 μm, and made of a biopolymer having a water vapour permeability coefficient P1, which increases with the average relative humidity and is at least 600 Barrer, determined at 23° C. and an average relative humidity of 25.5%; and on both sides of, and preferably in contact with, the intermediate layer; - two outer layers having a thickness of 100 nm to 20 μm, preferably 200 nm to 2.5 μm, and each consisting independently of the other of an organic polymer, both having a water vapour permeability coefficient P2 of 105 to 550 Barrer, preferably 110 to 520 Barrer, in particular 120 to 500 Barrer, determined at 23° C. and an average relative humidity of 25.5%; having method.

2. 2. The method of claim 1, wherein the biopolymer forming the intermediate layer is a biologically derived biopolymer selected from the group consisting of oxides, proteins, and synthetic polymers obtained from biologically derived monomers.

3. 3. The method according to claim 2, characterized in that the oside is selected from the group consisting of alginic acid, carrageenan, cellulose, in particular regenerated cellulose, chitin, chitosan, pectin, dextrin, starch, curdlan, FucoPol, gellan gum, pullulan and xanthan.

4. 3. The method of claim 2, wherein the protein is selected from the group consisting of gluten, isolated soy protein, zein, whey protein, casein, collagen and gelatin.

5. 5. The method according to claim 3 or 4, characterized in that the oxides and proteins are chemically modified.

6. 3. The method according to claim 2, characterized in that the synthetic polymers obtained from biological monomers are selected from the group consisting of polyhydroxyalkanoates (PHAs), polylactic acids (PLA), polyglycolic acids (PGA), poly(lactide-co-glycolides) (PLGA), polymers obtained by polymerization of lipid monomers, thermosetting polymers obtained by reaction of monosaccharides, disaccharides, oligosaccharides and / or alditols with polycarboxylic acids and / or polyaldehydes.

7. 2. The method of claim 1, wherein the biopolymer is a biodegradable polymer selected from the group consisting of aliphatic polyesters, aliphatic copolyesters, aromatic copolyesters, and polyesteramides.

8. 8. The method of claim 7, wherein the biodegradable biopolymer is selected from the group consisting of poly(caprolactone) (PCL), poly(butylene succinate) (PBS), poly(butylene succinate-co-adipate), and poly(butylene adipate-co-terephthalate) (PBAT).

9. 9. The method according to any one of claims 1 to 4 and 6 to 8, characterized in that the organic polymer constituting the outer layer is selected from the group consisting of semi-aromatic polyesters obtained by polycondensation of aliphatic polyols with aromatic polyacids, preferably poly(ethylene terephthalate), polybutylene terephthalate, poly(trimethylene terephthalate) and poly(ethylene naphthalate), and the corresponding copolyesters.

10. 2. The method of claim 1, wherein the middle layer is made of cellulose and the two outer layers are made of poly(ethylene terephthalate) (PET).

11. The method according to any one of claims 1 to 4, 6 to 8 and 10, characterized in that the active part of the membrane has a thickness of 5.0 μm to 240 μm, preferably 10 μm to 120 μm.

12. The method according to any one of claims 1 to 4, 6 to 8 and 10, characterized in that the vapor barrier membrane further comprises a reinforcing or protective layer in contact with one of the outer layers of the active part.

13. 11. The method according to any one of claims 1 to 4, 6 to 8 and 10, characterized in that the walls of the building or the walls of the rooms in the building are covered with a thermal insulation material and the vapour barrier membrane is applied in an internal position relative to the thermal insulation material or the membrane is integrated within the thermal insulation material.

14. 14. The method according to claim 13, characterized in that the heat insulation material is made of mineral or organic, natural, synthetic or man-made fibres.

15. 1. A humidity regulating vapor barrier membrane having an active portion, comprising: The active moiety is an intermediate layer having a thickness between 2 μm and 200 μm, preferably between 4 μm and 100 μm, and made of a biopolymer having a water vapour permeability coefficient P1, said water vapour permeability coefficient P1 increasing with the average relative humidity and being at least equal to 600 Barrer, determined at 23° C. and an average relative humidity of 25.5%; and on both sides of, and preferably in contact with, the intermediate layer. - two outer layers having a thickness of 100 nm to 20 μm, preferably 200 nm to 2.5 μm, and each consisting independently of the other of an organic polymer, both having a water vapour permeability coefficient P2 of 105 to 550 Barrer, preferably 110 to 520 Barrer, in particular 120 to 500 Barrer, determined at 23° C. and an average relative humidity of 25.5%; having Moisture Controlling Vapor Barrier Membrane.