MULTIFUNCTIONAL SYSTEM FOR PASSIVE HEAT AND WATER MANAGEMENT
In an embodiment, a multifunctional material system is provided and can include a variable-permeability layer, a desiccant containing layer, and a vapor-permeable supporting layer. The variable-permeability layer can have a vapor permeability that increases with increasing relative humidity. The desiccant containing layer can be adjacent the variable-permeability layer. The vapor-permeable supporting layer can be positioned adjacent at least one of the variable-permeability layer and the desiccant containing layer. Water moves in a first direction from the variable-permeability layer to the desiccant layer when relative humidity is greater adjacent the variable-permeability layer than the desiccant layer. Water moves a second, opposing direction, from the desiccant containing layer to the variable-permeability layer when the relative humidity is greater adjacent the desiccant containing layer than the variable-permeability layer. The rate of water motion in the first direction is greater than the second direction when the humidity gradient is reversed.
1 .- 19 . (canceled)
20 . A method of controlling humidity in an area of a building, the method comprising:
providing a multifunctional material system, the multifunctional material system comprising:
a variable-permeability component to be disposed on at least a portion of a surface of a wall; and
a desiccant component to be disposed on the variable-permeability component;
wherein, when the multifunctional material system is present on at least the portion of the surface of the wall, water is able to enter the desiccant component through the variable-permeability component when humidity is high on both a first side of the multifunctional material system and a second, opposing side of the multifunctional material system, and water is able to leave the desiccant component through the variable-permeability component when the humidity is low on both sides of the multifunctional material system, and
wherein, when the humidity is high, water is able to enter the desiccant component through the variable-permeability component at a rate greater than a rate of water able to exit the desiccant component through the variable-permeability component when the humidity is low.
21 . The method of claim 20 , wherein the desiccant component is substantially homogeneous.
22 . The method of claim 20 , wherein at least a portion of the desiccant component comprises desiccant material, and optionally a binder.
23 . The method of claim 22 , wherein the desiccant material is at least one of a silica gel, zeolites, calcium oxide (CaO 2 ), calcium sulfate (CaSO 4 ), lithium chloride (LiCl), a clay, or activated charcoal.
24 . The method of claim 20 , wherein the wall comprises oriented strand board (OSB), insulation, gypsum board, cement board, stucco, drywall, sheathing, roofing, cladding, an architectural membrane, or any combination thereof.
25 . The method of claim 20 , wherein the wall at least partially defines the area of the building, wherein the area is a bathroom.
26 . The method of claim 20 , wherein the wall at least partially defines the area of the building, wherein the area is a kitchen.
27 . The method of claim 20 , wherein the variable-permeability component and the desiccant component are separate and distinct from each other.
27 . A method of forming a multifunctional material system on at least a portion of a wall, the method comprising:
applying a variable-permeability layer to at least a portion of a surface of the wall; and
applying a desiccant layer to a surface of the variable-permeability layer that is opposite to another surface of the variable-permeability layer adjacent the wall,
wherein water is able to enter the desiccant layer through the variable-permeability layer when humidity is high on both a first side of the multifunctional material system and a second, opposing side of the multifunctional material system, wherein water is able to leave the desiccant layer through the variable-permeability layer when the humidity is low on both the first and second sides of the multifunctional material system, and
wherein, when the humidity is high, water is able to enter the desiccant layer through the variable-permeability layer at a rate that is greater than a rate of water able to exit the desiccant layer through the variable-permeability layer when the humidity is low.
28 . The method of claim 27 , wherein applying the variable-permeability layer comprises spray coating the variable-permeability layer to the substrate.
29 . The method of claim 27 , wherein applying the desiccant layer comprises spray coating the desiccant layer to the surface of the variable-permeability layer.
30 . The method of claim 27 , wherein at least a portion of the desiccant layer comprises desiccant material, and optionally a binder.
31 . The method of claim 27 , wherein the desiccant material is at least one of a silica gel, zeolites, calcium oxide (CaO 2 ), calcium sulfate (CaSO 4 ), lithium chloride (LiCl), a clay, or activated charcoal.
32 . The method of claim 27 , wherein the wall comprises oriented strand board (OSB), insulation, gypsum board, cement board, stucco, drywall, sheathing, roofing, cladding, an architectural membrane, or any combination thereof.
33 . The method of claim 27 , wherein the applying the variable-permeability layer comprises spreading an aqueous solution on at least the portion of the first surface of the wall.
34 . The method of claim 27 , wherein the applying the desiccant layer comprises depositing a slurry to the surface of the variable-permeability layer, the slurry comprising containing a binder and desiccant particles.
35 . The method of claim 27 , wherein the wall at least partially defines an area of a building.
36 . The method of claim 35 , wherein the area is a kitchen or a bathroom of the building.