AEROGEL- AND/OR XEROGEL-BASED MASS FOR ADVANCED MANUFACTURING AND USE THEREOF

Abstract

A composition, in particular for use as a printable and/or extrudable mass, comprises or consists of: 10-99.99 vol. % of a high-porosity material, whereby the high-porosity material is an aerogel and/or a xerogel, 0.001-5.0 vol. % of an organic binding promoter and, optionally, balance to 100 vol. % of further components.

Claims

1. Composition, in particular for use as a printable and/or extrudable mass, comprising or consisting of: a) 10-99.99 vol. %, especially 60-99.99 vol. %, in particular 80-99.99 vol. %, of a high-porosity material, whereby the high-porosity material is an aerogel and/or a xerogel b) 0.001-5.0 vol. % of an organic binding promoter c) optionally, balance to 100 vol. % of further components.

2. Composition according to claim 1, whereby the volume proportion of the high-porosity material, especially the aerogel, in the composition is 85-99.99 vol. %, most preferred 90-99.95 vol. %.

3. Composition according to any of claims 1-2, whereby apart from the high-porosity material, in particular the aerogel, the volume proportion of all of the other constituents of the composition in dry state is lower than 7 vol. %, preferably lower than 3 vol. % and even more preferably lower than 1 vol. %.

4. Composition according to any of claims 1-3, whereby the high-porosity material comprises or consist of an aerogel in the form of a silica-based aerogel, especially a hydrophobic silica-based aerogel, with a particle density of 140-170 kg/m.sup.3.

5. Composition according to any of claims 1-4, whereby the organic binding promotor comprises or consists of a surfactant, a block co-polymer, a fluoropolymer, a cellulose ether, carbohydrate starch ether and/or a redispersible polymer.

6. Composition according to claim 5, whereby the organic binding promotor comprises or consists of a surfactant, especially selected from the groups of ionic surfactants, amphoteric surfactants and/or nonionic surfactants.

7. Composition according to any of claims 5-6, whereby the binding promoter comprises or consists of a redispersible polymer, preferably a redispersible polymer based on one or more monomers selected from vinyl acetate, ethylene, vinyl alcohol, vinyl versatate, acrylate, styrene and/or acrylic ester.

8. Composition according to any of claims 1-7, whereby the composition additionally includes 0.001-43 vol. %, especially 0.001-28 vol. %, preferably 0.001-16 vol. %, of fillers chosen from mineral aggregates and/or organic aggregates.

9. Composition according to any of claims 1-8, whereby the composition additionally includes 0.001-25 vol. %, especially 0.001-5 vol. %, preferably 0.001-1 vol. %, of a binder, especially a mineral binder.

10. Composition according to any of claims 1-9, whereby the composition additionally includes 0.00028-7.0 vol. %, especially 0.00028-1.4 vol. %, preferably 0.00028-0.28 vol. %, of an expansive agent.

11. Composition according to claim 10, whereby the expansive agent is a compound, which is capable of reacting with silica and thereby generating an expansive product, especially the expansive agent is a magnesium salt, in particular magnesium oxide.

12. Composition according to claim 11, whereby the expansive agent and the binder both comprise or consist of magnesium compounds, especially magnesium salts, preferably magnesium oxide.

13. Composition according to any of claims 1-12, whereby the composition additionally includes 0.00028-7.0 vol. %, especially 0.00028-1.4 vol. %, preferably 0.00028-0.28 vol. %, of a curing agent.

14. Composition according to claim 13, whereby the curing agent is a water retaining additive, preferably a super absorbing polymer.

15. Composition according to any of claims 1-14, whereby the composition includes 0.001-15.0 vol. %, especially 0.001-5.0 vol. %, preferably 0.001-1.0 vol. %, of fibers.

16. Composition according to claim 15, whereby the fibers are in the form of mineral wool, glass wool, glass fibers and/or synthetic polymer fibers.

17. Composition according to any of claims 1-16, whereby the composition comprises or consists of: a) 80-99.99 vol. % of a high-porosity material, especially an aerogel b) 0.001-1.0 vol. % of an organic binding promoter, especially selected from surfactants and/or redispersible polymers c) 0.001-16 vol. % of fillers, especially selected from mineral aggregates d) 0.001-1 vol. %, of a binder, especially a mineral binder, preferably a cementitious binder e) optionally, 0.00028-0.28 vol. % of an expansive agent, especially a mineral based expansive agent f) optionally, 0.0001-0.02 vol. % of a curing agent, especially a super absorbing polymer g) optionally, 0.001-1 vol. %, fibers h) optionally, balance to 100 vol. % of further components.

18. Composition according to any of claims 1-17, whereby one or more particulate constituents of the composition, especially high-porosity material particles, most preferred aerogel particles, are present in agglomerated state.

19. Composition according to claim 18, whereby the agglomerates comprise or consist of the high-porosity material, the binding promoter and optionally the filler.

20. Composition according to any of claims 1-19, whereby the composition is present in the form of a free-flowing powder composition.

21. Composition according to any of claims 1-20, whereby the composition is a dry composition, whereby, preferably, with respect to the weight of the high-porosity material, a proportion of water in the composition is 0-2 wt. %, especially 0-1 wt. %, preferably 0-0.1 wt. %.

22. Composition according to any of claims 1-21, whereby the composition is free of a mineral binder, especially free of a hydraulic binder, in particular free of a cementitious binder.

23. Composition according to any of claims 1-22, whereby the composition comprises a volume proportion of the high-porosity material, in particular the aerogel, of 85-99.99 vol. %, most preferred 90-99.95 vol. %. and at the same time less than 5 vol. %, preferably less than 1 vol. %, of a mineral binder.

24. Workable mixture comprising a composition as described in any of claims 1-23 and water.

25. Workable mixture according to claim 24 whereby a weight proportion of water to the aerogel is from 0.2-3.5, especially 1-2.2, preferably 1.4-1.8.

26. Hardened composition obtainable by letting hardening a workable mixture as described in any of claims 24-25.

27. Composite element comprising a hardened composition as described in claim 26 and a substrate, especially a substrate comprising or consisting of concrete, wood, stone, rock, metal, glass, a polymeric material, glass fiber sheets, glass fiber mats, a ceramic, cardboard, paper or composites of these materials.

28. Composite element according to claim 27 whereby the substrate is a load bearing element, such as e.g. a panel, which carries the hardened composition and/or which acts as a structural element for the hardened composition.

29. Use of a composition according to any of claims 1-23 or a workable composition according to any of claims 24-25 as a printable mass in additive manufacturing, especially an additive free-space method, for producing a shaped body.

30. Use of a composition according to any of claims 1-23 or a workable composition according to any of claims 24-25 as an extrudable mass for producing a shaped body by extrusion, especially by extrusion on a mold.

31. Use of a composition according to any of claims 1-23, especially any of claims 16-17, or of a workable mixture according to any of claims 24-25, for producing a covering on a surface, especially for producing a render and/or a plaster on a surface, with a spray application technique, in particular with a shotcrete application technique.

32. Use according to claim 31, whereby the composition and/or the workable composition is used for producing a thermally insulating covering on a surface, especially for producing a thermally insulating render and/or a plaster on a surface.

33. Use of a composition according to any of claims 1-23, or of a workable mixture according to any of claims 24-25, for producing a shaped body by digital casting.

34. Use according to claim 33 whereby, the digital casting takes place in a mold and/or a formwork, especially in a mold and/or formwork that is moved and/or tilted during casting, whereby, preferably, the mold and/or formwork is vibrated during casting, especially for compacting the composition or the workable mixture.

35. Method for producing a shaped body from a composition according to any of claims 1-23 or a workable composition according to any of claims 24-25 by additive manufacturing, especially by an additive free-space method, digital casting and/or by extrusion.

36. Method according to claim 35 whereby the method is performed with a device having at least a supporting unit that supports a dispensing unit, especially a print head and/or an extrusion device, and whereby the supporting unit comprises a movement device which allows for moving the dispensing unit and the shaped body to be produced relative to each other in at least one spatial direction, preferably in all three spatial directions.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0248] FIG. 1 shows a robotic device while manufacturing an insulating wall of a building based on a composition according to the invention.

[0249] FIG. 2 shows two devices for manufacturing a composite element by a method according to the invention.

[0250] FIG. 3 shows a comparison between aerogel particles in original state (left side; not agglomerated) and aerogel particles in agglomerated state after processing (right side).

[0251] FIG. 4 shows a cross-section of the device used for measuring the compressive strength of aerogel particles in original state and agglomerated state.

[0252] FIG. 5 shows a perspective view of the device of FIG. 4.

[0253] FIG. 6 shows the mechanical strengths of processed (original) aerogel particles in comparison with agglomerated aerogel particles after processing. The measurement was done with the device shown in FIGS. 4 and 5.

EXEMPLARY EMBODIMENTS

[0254] FIG. 1 shows a robotic device 10 for manufacturing an insulating wall of a building 20. The device 10 shown in this example comprises a movable supporting unit 30 that is moving a print head 40 with a nozzle. The movable supporting unit 30 may be controlled by a computer control system. The device 10 is manufacturing the wall of a building 20 by adding several layers onto each other. The composition 100 that is dispensed by the dispensing unit 40 is stored in dry state in a storage container 50 comprising a transport unit 60 that is connected to the print head 40. The transport unit 60 comprises a mechanical mixing unit for mixing up the composition 100 with water in order to produce a workable composition before it is transported to the print head 40.

[0255] The composition 100 as introduced into the system is a dry composition, which is present in the form of a free-flowing powder and consists for example of: [0256] a) 95 vol. % of a hydrophobic silica-based aerogel with a particle density of 155 kg/m.sup.3. [0257] b) 0.5 vol. % of an organic binding promoter in the form of a powder polymer based on a block copolymer of PEG-PPG-PEG [0258] c) 4.5 vol. % of fillers in the form of sand with a maximum particle of 1 mm.

[0259] FIG. 2 illustrates a method of manufacturing substrates 21 and composite elements 22, 23 and 24, in particular architectural elements, by the use of two devices 11, 12. The first device 11 is a static extruder and the second device 12 is a 3D printer.

[0260] The first device 11 comprises a first container 51 with a mixing device 71. The first container 51 mixes several materials stored in three raw material containers 81. The so obtained mixture 200, e.g. a cementitious mortar composition, is used for producing a substrate 21. Thereby, the mixture 200 is extruded in a first step onto the movable surface 31 which is in this example realized by a conveying band that may comprise molds to produce the shape of the substrate 21 of the composite element.

[0261] The second step of the process is applying a composition 100 (which can be the same as described above) onto the substrate 21 with a second device 12. The second device 12 is in this example similar to the device 10 shown in FIG. 1. It comprises a movable second supporting unit 32 that is moving a second dispensing unit 42, which is connected to a second container 52. In other words, the example shown in FIG. 2 shows a combination of (i) a first manufacturing step with a static dispensing device 41 (extruder) and a movable surface 31 producing a substrate 21 from mixture 200 and (ii) a second manufacturing step with a movable dispensing device 42 (print head with adjustable nozzle) adding a layer of composition 100 onto a static surface, i.e. the substrate 21.

[0262] In the example shown here the second dispensing unit 42 is highly flexible since the addition of composition 100 on the back side of the composite element 21 is also possible.

[0263] The whole process is advantageously digitally controlled.

[0264] FIG. 2 shows a substrate 21 and three different final types of composite elements 22, 23 and 24 with different shapes that can be produced with the method according to the invention.

[0265] The substrate 21 has a continuous cross-section that can be produced only by extrusion on a conveying band without molds.

[0266] The first type of the composite element 22 shown here has a more complex shape, essentially built by printing a layer with varying thickness on top of substrate 21. The second type of the composite element 23 additionally has a varying curvature achieved by using a flexible nozzle on the dispensing device 41. The forth third of the composite element 24 has a varying thickness and curvature and comprises printed layers on both surfaces. Such structures with varying thicknesses and curvatures can for example be realized by using a flexible nozzle with adjustable opening.

[0267] It will be appreciated by those skilled in the art that the present invention can be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The presently disclosed embodiments are therefore considered in all respects to be illustrative and not restricting.

[0268] For example, it is possible to cover substrate 21 with composition 100 with constant thickness in order to produce a further composite element with a continuous cross-section.

[0269] Moreover, it is possible to use the first device 11 for producing a shaped body made from composition 100, if desired. Thereby, composition 100 is provided in the first container 51 and extruded onto the movable surface 31 or a conveying band, respectively. The so obtained shaped body can for example be used without further processing as an architectural element or it can be coated with a further material, e.g. a cementitious mortar composition or another composition according to the invention, with the second device 12, in order to produce a composite element.

[0270] Also, it is possible to use a transport device, e.g. a roller conveyer in the first device 11 which allows for continuously providing cardboard or paper in the region of the dispensing device 41 on the movable surface 31, such that the extruded mass is directly applied onto the cardboard or paper. Thus, in this way structures similar to gypsum wall-boards can be produced for example.

[0271] Furthermore, the inventive compositions can be applied on surfaces with standard spray equipment, especially a standard wet-mix or dry mix shotcrete equipment. Thereby, the compositions are for example conveyed through a hose and pneumatically projected at high velocity onto a surface.

[0272] In FIG. 3 on the left side, relatively small aerogel particles as originally provided are shown. On the right side of FIG. 3, the same aerogel particles after an agglomeration process are shown. The aerogel particles in agglomerated state were obtained by premixing the original aerogel particles in the presence of a small amount of water. Subsequently, the so obtained agglomerates were dried at elevated temperatures.

[0273] As can be deduced from FIG. 3, the agglomerates have a sizes in the range of several millimeters up to several centimeters. When mixing these agglomerates with water, the weakly bonded original particles of the agglomerates will fall apart and disperse in the water at least partially.

[0274] FIGS. 4 and 5 show the device used for measuring the compressive strength of the aerogel particles in original state and in agglomerated state. Specifically, the device comprises a piston which is movable in a square cylindrical cavity (10 cm×10 cm×20 cm). For measuring the mechanical strength, 150 g of the aerogel particles are introduced into the cavity and compress with the piston at a speed of 100 mm/min. Once the experiment was done with original particles and once with the particles in agglomerated state.

[0275] FIG. 6 shows the result of the measurement. As evident, processed aerogel particles in agglomerated state are mechanically more stable than the original granules. Specifically, the compressive strength at same deformation is about twice as high. This means that within application machines (pumps), the aerogel particles are twice as robust for withstanding high mechanical stresses during conveying (confined space of the rotostator) and spraying. Therefore, they can support higher mechanical loading before collapsing, thus better maintaining thermal insulating properties during application.