Biocomposite material and process for its preparation

Abstract

The invention relates to a new biocomposite material and its process of manufacture The biocomposite material of the invention is made of a recycled paper foam substrate, the porous structure of which is stiffened by microbiologically induced calcite precipitation (MICP), also known as biocalcification.

Description

[0001] BIOCOMPOSITE MATERIAL AND PROCESS FOR ITS PREPARATION

[0002] FIELD OF THE INVENTION

[0003] The invention relates to a new biocomposite material and its process of manufacture. The biocomposite material of the invention is made of a recycled paper foam substrate, the porous structure of which is stiffened by microbiologically induced calcite precipitation (MICP), also known as biocalcification.

[0004] PRIOR ART

[0005] Biocomposites represents a rapidly growing field of research and development driven by sustainable endeavours, focused on materials made from the combination of a polymer matrix and fibres, partly if not integrally sourced from renewable and biological resources (Jawaid, M., Sapuan, S.M. and Alothman, O.Y (eds) (2017) Green Biocomposites: Manufacturing and Properties. Cham: Springer International Publishing (Green Energy and Technology). Cellulose is the most abundant biopolymer found on Earth, presenting remarkable mechanical and biodegradable properties (Gibson, L.J. and Ashby, M.F. (1997) Cellular Solids: Structure and Properties. 2nd edn. Cambridge University Press'). It thereby represents an attractive alternative to fossil-based polymers in the fabrication of biocomposites in various context of applications including biomedical, architecture, construction and packaging industries (Ali, S.N. and Arafat, M.T. (2021) ‘Cellulose-based biocomposites’, in Green Biocomposites for Biomedical Engineering. Elsevier, pp. 135-195). Thanks to advancements in chemistry, cellulose can also now be transformed into various forms such as foams, films, and aerogels, all while preserving its main properties (Jiang, Z. and Ngai, T. (2022) ‘Recent Advances in Chemically Modified Cellulose and Its Derivatives for Food Packaging Applications: A Review’, Polymers, 14(8), p.

[0006] 1533). While virgin cellulose can be sourced from multiple plants, biocomposites processed from paper waste remain the exception rather than the rule, despite the large-scale deposits they represent.

[0007] Paper-based biocomposites processed through 3D printing are of particular interest for architecture and design, as these fields significantly consume mineral-based resources causingpollution and depletion. Yet proof of concepts, including prototypes, remain rare and primarily concentrate on paper pulp or slurry extrusion (Rech, A. et al. (2021) ‘Predicting Response: Waste-based biopolymer slurry recipe for 3d-printing), occasionally as additive in combination with mycelium (Goidea, A., Floudas, D. and Andreen, D. (2020) ‘Pulp faction: 3D printed material assemblies through microbial biotransformation’, in Fabricate 2020 - Making resilient architecture. London: UCL Press, pp. 42-49). However, the interest of processing paper waste as foam lies in extremely lightweight biocomposites, made from upcycled and local resources, and of which the material performance can be structurally graduated through 3D printing. Moreover, the biodesign field has lately proven that the polymer matrix of biocomposites can be processed at low temperature with minimal energetic inputs, through the metabolism of micro-organisms and without using fossil-fuel resources. For instance, microbiologically induced calcite precipitation (MICP), historically linked to the stabilization of soils and crack repairs in the built environment, has recently provided proof of concepts for various biocomposites processed from waste stream (Streich, B. (no date) ‘The irresistible illusion of finding a solution.’, Future Materials Bank), polymer lattice (Xin, A. et al. (2021) ‘Growing Living Composites with Ordered Microstructures and Exceptional Mechanical Properties’, Advanced Materials, 33(13), p. 2006946), textile (Beyer, B., Suarez, D. and Paiz, N. (2019) ‘Microbiologically Activated Knitted Composites Reimagining a column for the 21st century’, Blucher Design Proceedings, 7(1), pp. 541-552) or hydrogels (Hirsch, M. et al. (2023) ‘3D printing of living structural biocomposites’, Materials Today, 62, pp. 21-32). Recycled paper has been first used in this context as an additive for the enhancement of MICP sand (Chen, M. et al. (2021) ‘Used Paper Fibers for Sustainably Enhancing the MICP Stabilization of Sand’, in S.S. Kim, A.A.B. Moghal, and J. Yao (eds) Advances in Urban Geotechnical Engineering. Cham: Springer International Publishing (Sustainable Civil Infrastructures), pp. 52-64) and later as a foamy substrate (Mosse, A. and Bassereau, J.-F. (2022) ‘Material probes into paper waste as a bacterially-induced and 3D printed foam: Combining biodesign and circular principles’, in M.F. Hvejsel and P.J.S. Cruz (eds) Structures and Architecture A Viable Urban Perspective? 1st edn. CRC Press). Extruding foamy materials, whether cellulose-based or not, however remain a challenge, which partly explains why no more paper waste-based foam have been put forward so far (Bedarf, P. et al. (2021) ‘Foam 3D printing for construction: A review of applications, materials, and processes’, Automation in Construction, 130, p. 103861).BRIEF DESCRIPTION

[0008] In this context, a first subject matter of the invention is the use of plasticizer (in particular glycerol) and chitosan to produce a fiber foam liable to be 3D printed and / or biocalcified. A second subject matter of the invention concerns said fiber foam as such and its process of preparation. A third aspect of the invention relates to a biocal cified fiber foam made from said fiber foam enriched in plasticizer (in particular glycerol) and chitosan, and its process of preparation.

[0009] DETAILED DESCRIPTION

[0010] According to a first aspect, a subject matter of the invention relates to the use of plasticizer (in particular glycerol) and chitosan to produce a fiber foam liable to be:

[0011] ■ 3D printed; or

[0012] ■ biocalcified using a bacteria capable of microbial induced calcite precipitation, said bacteria being in particular Sporosarcina pasteurii, Bacillus arenosi, Sporosarcina urea, Brevibacterium ammoniagenes, Bacillus lentus, Proteus vulgaris, Myxococcus Xanthus or Helicobacter pylori,' or

[0013] ■ 3D printed and then biocalcified using a bacteria capable of microbial induced calcite precipitation, said bacteria being in particular Sporosarcina pasteurii, Bacillus arenosi, Sporosarcina urea, Brevibacterium ammoniagenes, Bacillus lentus, Proteus vulgaris, Myxococcus Xanthus o Helicobacter pylori.

[0014] While engaging with sustainable challenges, architects and designers are often shared between the potential of unusual abundant and renewable resources and the appropriation of pre- or postindustrial waste. Informed by a circular logic, the invention proposes a new microbiologically induced mineralised cellulose foam-based biocomposite integrally processed at room temperature (20°C-24°C) from paper waste while other ingredients are exclusively bio-based and biodegradable. In this way, the invention offers a biodesigned foam composite with a significantly lower environmental impact than synthetic foams dominating the packaging and built environment markets and incredibly lighter than other paper-based extruded composites. Besides, biocalcification significantly enhances flame retardancy of the invention without the use of chemicals that are harmful to human health, an important consideration when considering the application of such materials in architecture or interior design, - paper materials being traditionally known for their high flammability-. Finally, the invention is also more readily scalable compared to hydrogel-based MICP because its formulation is less temperature-sensitive, allowing more rapid development and more significant impact in design and architecture. All in all, by combining additive manufacturing, microbially induced process and the use of biodegradable and renewable resources, the invention contributes to the development of the bioeconomy by minimizing waste and reducing CO2 emission while circularizing one of the most common office and domestic waste.

[0015] Microbiologically induced calcium carbonate precipitation (MICP) is a bioprocess by which selected microorganisms can precipitate calcite through different pathways. Among these microorganisms the following ones are known: Sporosarcina pasteurii, Bacillus arenosi, Sporosarcina urea, Brevibacterium ammoniagenes, Bacillus lentus, Proteus vulgaris, Myxococcus Xanthus or Helicobacter pylori. According to another embodiment, a subject matter of the invention thus concerns the use of plasticizer (in particular glycerol) and chitosan as described above, wherein said bacteria is chosen among: Sporosarcina pasteurii, Bacillus arenosi, Sporosarcina urea, Brevibacterium ammoniagenes, Bacillus lentus, Proteus vulgaris, Myxococcus Xanthus and Helicobacter pylori. Advantageously, a subject matter of the invention concerns the use of plasticizer (in particular glycerol) and chitosan as described above, wherein said bacteria is Sporosarcina pasteurii.

[0016] According to another embodiment, a subject matter of the invention concerns the use of plasticizer (in particular glycerol) and chitosan as described above to produce a fiber foam liable to be:

[0017] ■ 3D printed; or

[0018] ■ biocalcified using a bacteria capable of microbial induced calcite precipitation, said bacteria being in particular Sporosarcina pasteurii, Bacillus arenosi, Sporosarcina urea, Brevibacterium ammoniagenes, Bacillus lentus, Proteus vulgaris, Myxococcus Xanthus or Helicobacter pylori,' or

[0019] ■ 3D printed and then biocalcified using a bacteria capable of microbial induced calcite precipitation, said bacteria being in particular Sporosarcina pasteurii, Bacillus arenosi, Sporosarcina urea, Brevibacterium ammoniagenes, Bacillus lentus, Proteus vulgaris, Myxococcus Xanthus or Helicobacter pylori, wherein said fiber foam comprises:

[0020] ■ from 0.5% to 4.5% of weight of plasticizer (in particular glycerol) relative to the total weight of the fiber foam; andfrom 0.2% to 2.0% of weight of chitosan relative to the total weight of the fiber foam.

[0021] According to another embodiment, a subject matter of the invention concerns the use of plasticizer (in particular glycerol) and chitosan as described above, wherein said fiber foam further comprises from 4% to 10% of weight of a foaming agent relative to the total weight of the fiber foam. According to another embodiment, a subject matter of the invention concerns the use of plasticizer (in particular glycerol) and chitosan as described above, wherein said fiber foam further comprises from 10% to 19% of weight of a fiber shred, the granulometry of which is less than or equal to 500 pm, relative to the total weight of the fiber foam, said fiber shred comprising at least 50% of a fiber chosen among: textile fiber, cellulose fiber and their combination.

[0022] According to another embodiment, a subject matter of the invention concerns the use of plasticizer (in particular glycerol) and chitosan as described above, wherein said fiber foam further comprises from 2% to 7% of weight of a binding agent relative to the total weight of the fiber foam.

[0023] According to another embodiment, a subject matter of the invention concerns the use of plasticizer (in particular glycerol) and chitosan as described above, wherein said fiber foam further comprises from 60% to 80% of weight of water relative to the total weight of the fiber foam.

[0024] According to another embodiment, a subject matter of the invention concerns the use of plasticizer (in particular glycerol) and chitosan as described above, wherein said fiber foam comprises:

[0025] ■ from 0.5% to 4.5% of weight of plasticizer (in particular glycerol) relative to the total weight of the fiber foam;

[0026] ■ from 0.2% to 2.0% of weight of chitosan relative to the total weight of the fiber foam;

[0027] ■ from 4% to 10% of weight of a foaming agent relative to the total weight of the fiber foam;

[0028] ■ from 2% to 7% of weight of a binding agent relative to the total weight of the fiber foam;■ from 60% to 80% of weight of water relative to the total weight of the fiber foam; and

[0029] ■ from 10% to 19% of weight of a fiber shred, the granulometry of which is less than or equal to 500 pm, relative to the total weight of the fiber foam, said fiber shred comprising at least 50% of a fiber chosen among: textile fiber, cellulose fiber and their combination (i.e. mixture of textile fiber and cellulose fiber).

[0030] “Plasticizer” refers to substance that is added to a material to make it softer and more flexible, to increase its plasticity, to decrease its viscosity, and / or to decrease friction during its handling in manufacture. Interestingly, bio-based plasticizers are often used in 3D printing, especially in paste and foam extrusion, to improve flexibility, processability, and the overall performance of the material. These plasticizers are derived from renewable sources and are considered more environmentally friendly compared to traditional petrochemical-based plasticizers. Some examples are:

[0031] ■ Vegetable Oil-Based Plasticizers such as Epoxidized soybean oil (ESO);

[0032] ■ Bio-Based Esters such as Butyl oleate or dioctyl adipate (DOA);

[0033] ■ Glycerol which is a byproduct of biodiesel production;

[0034] ■ Lactic Acid-Based Plasticizers such as triethyl lactate;

[0035] ■ Sucrose Esters; or

[0036] ■ Bio-Based Polymeric Plasticizers such as polyurethane-based plasticizers derived from bio-based polyols.

[0037] “From 0.5% to 4.5% of weight of plasticizer (in particular glycerol)” means from 0.5% to 4.5%, from 0.5% to 4.0%, from 0.5% to 3.5%, from 0.5% to 3.0%, from 0.5% to 2.5%, from 0.5% to 2.0%, from 0.5% to 1.5%, from 0.5% to 1.0%, from 1.0% to 4.5%, from 1.5% to 4.5%, from 2.0% to 4.5%, from 2.5% to 4.5%, from 3.0% to 4.5%, from 3.5% to 4.5%, from 4.0% to 4.5%, from 1.0% to 4.0%, from 1.5% to 3.5% or from 2.0% to 3.0%. It also means that plasticizer (in particular glycerol) may represent 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2%, 2.1%, 2.2%, 2.3%, 2.4%, 2.5%, 2.6%, 2.7%, 2.8%, 2.9%, 3%, 3.1%, 3.2%, 3.3%, 3.4%, 3.5%, 3.6%, 3.7%, 3.8%, 3.9%, 4%, 4.1%, 4.2%, 4.3%, 4.4% or 4.5% of weight relative to the total weight of the fiber foam. Advantageously, plasticizer (in particular glycerol) represents 2.3% or 2.5% of weight relative to the total weight of the fiber foam.According to another embodiment, a subject matter of the invention concerns the use of plasticizer (in particular glycerol) and chitosan as described above, wherein said plasticizer is chosen among:

[0038] ■ Vegetable Oil-Based Plasticizers such as Epoxidized soybean oil (ESO);

[0039] ■ Bio-Based Esters such as Butyl oleate or dioctyl adipate (DOA);

[0040] ■ Glycerol;

[0041] ■ Lactic Acid-Based Plasticizers such as triethyl lactate;

[0042] ■ Sucrose Esters; or

[0043] ■ Bio-Based Polymeric Plasticizers such as polyurethane-based plasticizers derived from bio-based polyols.

[0044] Advantageously, a subject matter of the invention concerns the use of plasticizer (in particular glycerol) and chitosan as described above, wherein said plasticizer is glycerol.

[0045] “From 0.2% to 2.0% of weight of chitosan” means from 0.2% to 2.0%, from 0.2% to 1.9%, from 0.2% to 1.8%, from 0.2% to 1.7%, from 0.2% to 1.6%, from 0.2% to 1.5%, from 0.2% to 1.4%, from 0.2% to 1.3%, from 0.2% to 1.2%, from 0.2% to 1.1%, from 0.2% to 1%, from 0.2% to 0.9%, from 0.2% to 0.8%, from 0.2% to 0.7%, from 0.2% to 0.6%, from 0.2% to 0.5%, from 0.4% to 0.9%, from 0.2% to 0.3%, from 0.3% to 2.0%, from 0.4% to 2.0%, from 0.5% to 2.0%, from 0.6% to 2.0%, from 0.7% to 2.0%, from 0.8% to 2.0%, from 0.9% to 2.0%, from 1% to 2.0%, from 1.1% to 2.0%, from 1.2% to 2.0%, from 1.3% to 2.0%, from 1.4% to 2.0%, from 1.5% to 2.0%, from 1.6% to 2.0%, from 1.7% to 2.0%, from 1.8% to 2.0%, from 1.9% to 2.0% or from 0.5% to 1.0%. It also means that chitosan may represent 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1.0%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9% or 2% of weight relative to the total weight of the fiber foam. Advantageously, chitosan represents 0.8% or 0.9% of weight relative to the total weight of the fiber foam.

[0046] To facilitate the implementation of the chitosan, it can be previously dissolved in an aqueous solution of a pH comprises from 2 to 3, in particular from 2.4 to 2.6, preferably with a pH of 2.5. Said aqueous solution is made using a weak acid, in particular a weak acid chosen among: acetic acid, lactic acid, formic acid, malic acid, succinic acid, adipic acid and carbonic acid. Advantageously, acetic acid is used. It has to be pointed out that said chitosan solution may advantageously comprise from 2% to 10% of weight of chitosan relative to the total weight of the chitosan solution.“From 2% to 10% of weight of chitosan relative to the total weight of the chitosan solution” means from 2% to 3%, from 2% to 4%, from 2% to 5%, from 2% to 6%, from 2% to 7%, from 2% to 8%, from 2% to 9%, from 2% to 10%, from 3% to 10%, from 4% to 10%, from 5% to 10%, from 6% to 10%, from 7% to 10%, from 8% to 10%, from 9% to 10% or from 3% to 5%. It also means that chitosan may represent 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9% or 10% of weight relative to the total weight of the chitosan solution. Advantageously, chitosan represents 4% of weight relative to the total weight of chitosan solution.

[0047] According to another embodiment, a subject matter of the invention concerns the use of plasticizer (in particular glycerol) and chitosan as described above, wherein said fiber foam further comprises an acid, in particular a weak acid, the concentration of which is from 0.1% to 1.5% of weight of acid relative to the total weight of the fiber foam.

[0048] “From 0.1% to 1.5% of weight of acid relative to the total weight of the fiber foam” means from 0.1% to 0.2%, from 0.1% to 0.3%, from 0.1% to 0.4%, from 0.1% to 0.5%, from 0.1% to 0.6%, from 0.1% to 0.7%, from 0.1% to 0.8%, from 0.1% to 0.9%, from 0.1% to 1.0%, from 0.1% to 1.1%, from 0.1% to 1.2%, from 0.1% to 1.3%, from 0.1% to 1.4%, from 0.1% to 1.5%, from 0.2% to 1.5%, from 0.3% to 1.5%, from 0.4% to 1.5%, from 0.5% to 1.5%, from 0.6% to 1.5%, from 0.7% to 1.5%, from 0.8% to 1.5%, from 0.9% to 1.5%, from 1.0% to 1.5%, from 1.1% to 1.5%, from 1.2% to 1.5%, from 1.3% to 1.5%, from 1.4% to 1.5% or from 0.5% to 0.8%. It also means that acid may represent 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1.0%, 1.1%, 1.2%, 1.3%, 1.4% or 1.5% of weight relative to the total weight of the fiber foam. Advantageously, acid represents 0.6% or 0.7% of weight relative to the total weight of the fiber foam.

[0049] “Foaming agent” means a material that facilitates the formation of a foam such as a blowing agent or a surfactant, which is capable of modifying the surface tension between 2 surfaces. In the invention, said foaming agent may be chosen among:

[0050] ■ vinyl alcohol (PVA) / polyvinyl acetate (PVAc) copolymers (or PVA / PVAc copolymer); and

[0051] ■ dishwashing products and foaming agent based on the following mixture:

[0052] grapes, liquorice roots, black tea and lemon (= Genfil®).“Genfil®” is a bio-sourced foaming agent (registered trademark of ARTRAIN§AAT PEYZAJ PLASTIK SANAYI VE TICARET LiMITED §iRKETi), which is a composition based on herbal resins with a component made of a mixture of grapes, licorice roots, black tea and lemon.

[0053] “From 4% to 10% of weight of a foaming agent” means from 4% to 10.0%, from 4% to 4.5%, from 4% to 5.0%, from 4% to 5.5%, from 4% to 6.0%, from 4% to 6.5%, from 4% to 7.0%, from 4% to 7.5%, from 4% to 8.0%, from 4% to 8.5%, from 4% to 9.0%, from 4% to 9.5%, from 4.5% to 10.0%, from 5.0% to 10.0%, from 5.5% to 10.0%, from 6.0% to 10.0%, from 6.5% to 10.0%, from 7.0% to 10.0%, from 7.5% to 10.0%, from 8.0% to 10.0%, from 8.5% to 10.0%, from 9.0% to 10.0%, from 9.5% to 10.0%, from 5% to 6%, from 5% to 9% or from 8% to 9%. It also means that foaming agent may represent 4.0%, 4.1%, 4.2%, 4.3%, 4.4%, 4.5%, 4.6%, 4.7%, 4.8%, 4.9%, 5.0%, 5.1%, 5.2%, 5.3%, 5.4%, 5.5%, 5.6%, 5.7%, 5.8%, 5.9%, 6.0%, 6.1%, 6.2%, 6.3%, 6.4%, 6.5%, 6.6%, 6.7%, 6.8%, 6.9%, 7.0%, 7.1%, 7.2%, 7.3%, 7.4%, 7.5%, 7.6%, 7.7%, 7.8%, 7.9%, 8.0%, 8.1%, 8.2%, 8.3%, 8.4%, 8.5%, 8.6%, 8.7%, 8.8%, 8.9%, 9.0%, 9.1%, 9.2%, 9.3%, 9.4%, 9.5%, 9.6%, 9.7%, 9.8%, 9.9% or 10.0% of weight relative to the total weight of the fiber foam. Advantageously, foaming agent represents 5.7% or 8.5% of weight relative to the total weight of the fiber foam.

[0054] “Binding agent” means a substance capable of joining two surfaces in contact by creating durable bonds. In the invention, said binding agent derives from polymeric sources and may be chosen among polysaccharides such as starch-based glues, starch, xanthan gum, guar gum, cellulosic gum or alginate, proteins such as pectin and casein; and synthetic clay such as Laponite® (in particular Laponite® RD available on Mon-Droguiste.com).

[0055] “From 2% to 7% of weight of an binding agent” means from 2% to 7%, From 2% to 2.3%, from 2% to 2.6%, from 2% to 2.9%, from 2% to 3.2%, from 2% to 3.5%, from 2% to 3.8%, from 2% to 4.1%, from 2% to 4.4%, from 2% to 4.7%, from 2% to 5.0%, from 2% to 5.3%, from 2% to 5.6%, from 2% to 5.9%, from 2% to 6.2%, from 2% to 6.5%, from 2% to 6.8%, from 2% to 7.0%, from 2.3% to 7.0%, from 2.6% to 7.0%, from 2.9% to 7.0%, from 3.2% to 7.0%, from 3.5% to 7.0%, from 3.8% to 7.0%, from 4.1% to 7.0%, from 4.4% to 7.0%, from 4.7% to 7.0%, from 5.0% to 7.0%, from 5.3% to 7.0%, from 5.6% to 7.0%, from 5.9% to 7.0%, from 6.2% to 7.0%, from 6.5% to 7.0%, from 6.8% to 7.0%, from 3% to 6%, from 3% to 6% or from 4% to 5%. It also means that binding agent may represent 2.0%, 2.1%, 2.2%, 2.3%, 2.4%, 2.5%, 2.6%, 2.7%, 2.8%, 2.9%, 3.0%, 3.1%, 3.2%, 3.3%, 3.4%, 3.5%, 3.6%, 3.7%, 3.8%, 3.9%, 4.0%, 4.1%, 4.2%, 4.3%, 4.4%, 4.5%, 4.6%, 4.7%, 4.8%, 4.9%, 5.0%, 5.1%, 5.2%, 5.3%, 5.4%, 5.5%, 5.6%,5.7%, 5.8%, 5.9%, 6.0%, 6.1%, 6.2%, 6.3%, 6.4%, 6.5%, 6.6%, 6.7%, 6.8%, 6.9% or 7.0% of weight relative to the total weight of the fiber foam. Advantageously, binding agent represents 4.3% or 4.6% of weight relative to the total weight of the fiber foam.

[0056] “From 60% to 80% of weight of water” means from 60% to 61%, from 60% to 62%, from 60% to 63%, from 60% to 64%, from 60% to 65%, from 60% to 66%, from 60% to 67%, from 60% to 68%, from 60% to 69%, from 60% to 70%, from 60% to 71%, from 60% to 72%, from 60% to 73%, from 60% to 74%, from 60% to 75%, from 60% to 76%, from 60% to 77%, from 60% to 78%, from 60% to 79%, from 60% to 80%, from 61% to 80%, from 62% to 80%, from 63% to 80%, from 64% to 80%, from 65% to 80%, from 66% to 80%, from 67% to 80%, from 68% to 80%, from 69% to 80%, from 70% to 80%, from 71% to 80%, from 72% to 80%, from 73% to 80%, from 74% to 80%, from 75% to 80%, from 76% to 80%, from 77% to 80%, from 78% to 80%, from 79% to 80%, from 64% to 65%, from 64% to 70% or from 69% to 70%. It also means that water may represent 60.0%, 60.1%, 60.2%, 60.3%, 60.4%, 60.5%, 60.6%, 60.7%, 60.8%, 60.9%, 61.0%, 61.1%, 61.2%, 61.3%, 61.4%, 61.5%, 61.6%, 61.7%, 61.8%, 61.9%, 62.0%, 62.1%, 62.2%, 62.3%, 62.4%, 62.5%, 62.6%, 62.7%, 62.8%, 62.9%, 63.0%, 63.1%, 63.2%, 63.3%, 63.4%, 63.5%, 63.6%, 63.7%, 63.8%, 63.9%, 64.0%, 64.1%, 64.2%, 64.3%, 64.4%, 64.5%, 64.6%, 64.7%, 64.8%, 64.9%, 65.0%, 65.1%, 65.2%, 65.3%, 65.4%, 65.5%, 65.6%, 65.7%, 65.8%, 65.9%, 66.0%, 66.1%, 66.2%, 66.3%, 66.4%, 66.5%, 66.6%, 66.7%, 66.8%, 66.9%, 67.0%, 67.1%, 67.2%, 67.3%, 67.4%, 67.5%, 67.6%, 67.7%, 67.8%, 67.9%, 68.0%, 68.1%, 68.2%, 68.3%, 68.4%, 68.5%, 68.6%, 68.7%, 68.8%, 68.9%, 69.0%, 69.1%, 69.2%, 69.3%, 69.4%, 69.5%, 69.6%, 69.7%, 69.8%, 69.9%, 70.0%, 70.1%, 70.2%, 70.3%, 70.4%, 70.5%, 70.6%, 70.7%, 70.8%, 70.9%, 71.0%, 71.1%, 71.2%, 71.3%, 71.4%, 71.5%, 71.6%, 71.7%, 71.8%, 71.9%, 72.0%, 72.1%, 72.2%, 72.3%, 72.4%, 72.5%, 72.6%, 72.7%, 72.8%, 72.9%, 73.0%, 73.1%, 73.2%, 73.3%, 73.4%, 73.5%, 73.6%, 73.7%, 73.8%, 73.9%, 74.0%, 74.1%, 74.2%, 74.3%, 74.4%, 74.5%, 74.6%, 74.7%, 74.8%, 74.9%, 75.0%, 75.1%, 75.2%, 75.3%, 75.4%, 75.5%, 75.6%, 75.7%, 75.8%, 75.9%, 76.0%, 76.1%, 76.2%, 76.3%, 76.4%, 76.5%, 76.6%, 76.7%, 76.8%, 76.9%, 77.0%, 77.1%, 77.2%, 77.3%, 77.4%, 77.5%, 77.6%, 77.7%, 77.8%, 77.9%, 78.0%, 78.1%, 78.2%, 78.3%, 78.4%, 78.5%, 78.6%, 78.7%, 78.8%, 78.9%, 79.0%, 79.1%, 79.2%, 79.3%, 79.4%, 79.5%, 79.6%, 79.7%, 79.8%, 79.9% or 80.0% of weight relative to the total weight of the fiber foam. Advantageously, water represents 64.7% or 69.5% of weight relative to the total weight of the fiber foam.“Fiber shred” is obtained by reducing textile fiber and / or cellulose fiber in a shredder and then grinding them in a grain or laboratory mill to obtain a homogeneous mill of a granulometry less than or equal to 500 pm.

[0057] “Less than or equal to 500 pm” means that the granulometry may be less than or equal to 500 pm, less than or equal to 450 pm, less than or equal to 400 pm, less than or equal to 350 pm, less than or equal to 300 pm, less than or equal to 250 pm, less than or equal to 200 pm, less than or equal to 150 pm, less than or equal to 100 pm or less than or equal to 500 pm. Take together, this means that the granulometry may be comprised from 50 pm to 500 pm, from 100 pm to 500 pm, from 150 pm to 500 pm, from 200 pm to 500 pm, from 250 pm to 500 pm, from 300 pm to 500 pm, from 350 pm to 500 pm, from 400 pm to 500 pm, from 450 pm to 500 pm, from 50 pm to 450 pm, from 50 pm to 400 pm, from 50 pm to 350 pm, from 50 pm to 300 pm, from 50 pm to 250 pm, from 50 pm to 200 pm, from 50 pm to 150 pm, from 50 pm to 100 pm, from 100 pm to 400 pm, from 200 pm to 300 pm, from 150 pm to 350 pm or from 250 pm to 450 pm. It also means that the granulometry may be 50 pm, 100 pm, 150 pm, 200 pm, 250 pm, 300 pm, 350 pm, 400 pm, 450 pm or 500 pm. Advantageously, said fiber shred is a homogeneous mill of a granulometry less than or equal to 250 pm, particularly when 3D printing is performed with a 4 mm nozzle.

[0058] “From 10% to 19% of weight of a fiber shred” means from 10% to 10.5%, from 10% to 11%, from 10% to 11.5%, from 10% to 12%, from 10% to 12.5%, from 10% to 13%, from 10% to 13.5%, from 10% to 14%, from 10% to 14.5%, from 10% to 15%, from 10% to 15.5%, from 10% to 16%, from 10% to 16.5%, from 10% to 17%, from 10% to 17.5%, from 10% to 18%, from 10% to 18.5%, from 10% to 19%, from 10.5% to 19%, from 11% to 19%, from 11.5% to 19%, from 12% to 19%, from 12.5% to 19%, from 13% to 19%, from 13.5% to 19%, from 14% to 19%, from 14.5% to 19%, from 15% to 19%, from 15.5% to 19%, from 16% to 19%, from 16.5% to 19%, from 17% to 19%, from 17.5% to 19%, from 18% to 19%, from 18.5% to 19%, from 14.5% to 15.5%, from 14.5% to 16% or from 15.5% to 16.5%. It also means that fiber shred may represent 10.0%, 10.1%, 10.2%, 10.3%, 10.4%, 10.5%, 10.6%, 10.7%, 10.8%, 10.9%, 11.0%, 11.1%, 11.2%, 11.3%, 11.4%, 11.5%, 11.6%, 11.7%, 11.8%, 11.9%, 12.0%, 12.1%, 12.2%, 12.3%, 12.4%, 12.5%, 12.6%, 12.7%, 12.8%, 12.9%, 13.0%, 13.1%, 13.2%, 13.3%, 13.4%, 13.5%, 13.6%, 13.7%, 13.8%, 13.9%, 14.0%, 14.1%, 14.2%, 14.3%, 14.4%, 14.5%, 14.6%, 14.7%, 14.8%, 14.9%, 15.0%, 15.1%, 15.2%, 15.3%, 15.4%, 15.5%, 15.6%, 15.7%, 15.8%, 15.9%, 16.0%, 16.1%, 16.2%, 16.3%, 16.4%, 16.5%, 16.6%, 16.7%, 16.8%,16.9%, 17.0%, 17.1%, 17.2%, 17.3%, 17.4%, 17.5%, 17.6%, 17.7%, 17.8%, 17.9%, 18.0%, 18.1%, 18.2%, 18.3%, 18.4%, 18.5%, 18.6%, 18.7%, 18.8%, 18.9% or 19.0% of weight relative to the total weight of the fiber foam. Advantageously, fiber shred represents 14.9% or 16.1% of weight relative to the total weight of the fiber foam.

[0059] According to another embodiment, a subject matter of the invention concerns the use of plasticizer (in particular glycerol) and chitosan as described above, wherein said fiber foam further comprises from 2.5% to 5.5% of weight of gelatin relative to the total weight of the fiber foam.

[0060] “From 2.5% to 5.5% of weight of gelatin” means from 2.5% to 5.5%, From 2.5% to 3.0%, from 2.5% to 3.5%, from 2.5% to 4.0%, from 2.5% to 4.5%, from 2.5% to 5.0%, from 2.5% to 5.5%, from 3.0% to 5.5%, from 3.5% to 5.5%, from 4.0% to 5.5%, from 4.5% to 5.5%, from 5.0% to 5.5%, from 3% to 4.5%, from 3.5% to 4.5% or from 3.5% to 4%. It also means that gelatin may represent 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2.0%, 2.1%, 2.2%, 2.3%, 2.4%, 2.5%, 2.6%, 2.7%, 2.8%, 2.9%, 3.0%, 3.1%, 3.2%, 3.3%, 3.4% or 3.5% of weight relative to the total weight of the fiber foam. Advantageously, gelatin represents 3.8% of weight relative to the total weight of the fiber foam.

[0061] According to another embodiment, a subject matter of the invention concerns the use of plasticizer (in particular glycerol) and chitosan as described above, wherein said fiber foam comprises or consists of:

[0062] ■ 2.3% or 2.5% of weight of plasticizer (in particular glycerol) relative to the total weight of the fiber foam;

[0063] ■ 0.8% or 0.9% of weight of chitosan relative to the total weight of the fiber foam;

[0064] ■ 5.7% or 8.5% of weight of a foaming agent relative to the total weight of the fiber foam;

[0065] ■ 4.3% or 4.6% of weight of a binding agent relative to the total weight of the fiber foam;

[0066] ■ 64.7% or 69.5% of weight of water relative to the total weight of the fiber foam;

[0067] and

[0068] ■ 14.9% or 16.1% of weight of a fiber shred, the granulometry of which is less than or equal to 500 pm, relative to the total weight of the fiber foam, said fiber shred comprising at least 50% of a fiber chosen among: textile fiber, cellulose fiber and their combination.“Fiber shred, the granulometry of which is less than or equal to 500 pm” means, as previously defined, that the fiber shred has a granulometry less than or equal to 500 pm, in particular less than or equal to 250 pm.

[0069] “Said fiber shred comprising at least 50% of a fiber chosen among: textile fiber, cellulose fiber and their combination” means that said fiber shred is made up of 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95% or 100% of a fiber chosen among: textile fiber, cellulose fiber and their combination (i.e. mixture of textile fiber and cellulose fiber).

[0070] According to another embodiment, a subject matter of the invention concerns the use of plasticizer (in particular glycerol) and chitosan as described above, wherein said fiber foam further comprises an acid, in particular a weak acid, the concentration of which is 0.6% or 0.7% of weight of acid relative to the total weight of the fiber foam.

[0071] According to another embodiment, a subject matter of the invention concerns the use of plasticizer (in particular glycerol) and chitosan as described above, wherein said fiber foam comprises:

[0072] ■ 2.5% of weight of plasticizer (in particular glycerol) relative to the total weight of the fiber foam;

[0073] ■ 0.9% of weight of chitosan relative to the total weight of the fiber foam;

[0074] ■ 5.7% of weight of a foaming agent relative to the total weight of the fiber foam;

[0075] ■ 4.6% of weight of a binding agent relative to the total weight of the fiber foam;

[0076] ■ 69.5% of weight of water relative to the total weight of the fiber foam; and ■ 16.1% of weight of a fiber shred, the granulometry of which is less than or equal to 500 pm, relative to the total weight of the fiber foam, said fiber shred comprising at least 50% of a fiber chosen among: textile fiber, cellulose fiber and their combination.

[0077] According to another embodiment, a subject matter of the invention concerns the use of plasticizer (in particular glycerol) and chitosan as described above, wherein said fiber foam consists of:

[0078] ■ 2.5% of weight of plasticizer (in particular glycerol) relative to the total weight of the fiber foam;

[0079] ■ 0.9% of weight of chitosan relative to the total weight of the fiber foam;■ 0.7% of weight of acid (in particular acetic acid) relative to the total weight of the fiber foam;

[0080] ■ 5.7% of weight of a foaming agent relative to the total weight of the fiber foam;

[0081] ■ 4.6% of weight of a binding agent relative to the total weight of the fiber foam;

[0082] ■ 69.5% of weight of water relative to the total weight of the fiber foam; and ■ 16.1% of weight of a fiber shred, the granulometry of which is less than or equal to 500 pm, relative to the total weight of the fiber foam, said fiber shred comprising at least 50% of a fiber chosen among: textile fiber, cellulose fiber and their combination.

[0083] According to another embodiment, a subject matter of the invention concerns the use of plasticizer (in particular glycerol) and chitosan as described above, wherein said fiber foam comprises:

[0084] ■ 2.3% of weight of plasticizer (in particular glycerol) relative to the total weight of the fiber foam;

[0085] ■ 0.8% of weight of chitosan relative to the total weight of the fiber foam;

[0086] ■ 8.5% of weight of a foaming agent relative to the total weight of the fiber foam;

[0087] ■ 4.3% of weight of a binding agent relative to the total weight of the fiber foam;

[0088] ■ 64.7% of weight of water relative to the total weight of the fiber foam; and ■ 14.9% of weight of a fiber shred, the granulometry of which is less than or equal to 500 pm, relative to the total weight of the fiber foam, said fiber shred comprising at least 50% of a fiber chosen among: textile fiber, cellulose fiber and their combination.

[0089] According to another embodiment, a subject matter of the invention concerns the use of plasticizer (in particular glycerol) and chitosan as described above, wherein said fiber foam comprises:

[0090] ■ 2.3% of weight of plasticizer (in particular glycerol) relative to the total weight of the fiber foam;

[0091] ■ 0.8% of weight of chitosan relative to the total weight of the fiber foam;

[0092] ■ 0.6% of weight of acid (in particular acetic acid) relative to the total weight of the fiber foam;

[0093] ■ 8.5% of weight of a foaming agent relative to the total weight of the fiber foam;

[0094] ■ 4.3% of weight of a binding agent relative to the total weight of the fiber foam;■ 64.7% of weight of water relative to the total weight of the fiber foam; and ■ 14.9% of weight of a fiber shred, the granulometry of which is less than or equal to 500 gm, relative to the total weight of the fiber foam, said fiber shred comprising at least 50% of a fiber chosen among: textile fiber, cellulose fiber and their combination..

[0095] According to another embodiment, a subject matter of the invention concerns the use of plasticizer (in particular glycerol) and chitosan as described above, wherein said fiber foam consists of:

[0096] ■ 2.3% of weight of plasticizer (in particular glycerol) relative to the total weight of the fiber foam;

[0097] ■ 0.8% of weight of chitosan relative to the total weight of the fiber foam;

[0098] ■ 0.6% of weight of acid (in particular acetic acid) relative to the total weight of the fiber foam;

[0099] ■ 3.8% of weight of gelatin relative to the total weight of the fiber foam; ■ 8.5% of weight of a foaming agent relative to the total weight of the fiber foam;

[0100] ■ 4.3% of weight of a binding agent relative to the total weight of the fiber foam;

[0101] ■ 64.7% of weight of water relative to the total weight of the fiber foam; and ■ 14.9% of weight of a fiber shred, the granulometry of which is less than or equal to 500 pm, relative to the total weight of the fiber foam, said fiber shred comprising at least 50% of a fiber chosen among: textile fiber, cellulose fiber and their combination.

[0102] According to a second aspect, a subject matter of the invention relates to a fiber foam comprising:

[0103] ■ from 0.5% to 4.5% of weight of plasticizer (in particular glycerol) relative to the total weight of the fiber foam;

[0104] ■ from 0.2% to 2.0% of weight of chitosan relative to the total weight of the fiber foam;

[0105] ■ from 4% to 10% of weight of a foaming agent relative to the total weight of the fiber foam;

[0106] ■ from 2% to 7% of weight of a binding agent relative to the total weight of the fiber foam;■ from 60% to 80% of weight of water relative to the total weight of the fiber foam; and

[0107] ■ from 10% to 19% of weight of a fiber shred, the granulometry of which is less than or equal to 500 gm, relative to the total weight of the fiber foam, said fiber shred comprising at least 50% of a fiber chosen among: textile fiber, cellulose fiber and their combination.

[0108] According to another embodiment, a subject matter of the invention concerns the fiber foam as described above, wherein said plasticizer is glycerol.

[0109] According to another embodiment, a subject matter of the invention concerns the fiber foam as described above, said fiber foam further comprises from 1.5% to 3.5% of weight of calcium chloride relative to the total weight of the fiber foam.

[0110] According to another embodiment, a subject matter of the invention concerns the fiber foam as described above, wherein said fiber foam further comprises an acid, in particular a weak acid, the concentration of which is from 0.1% to 1.5% of weight of acid relative to the total weight of the fiber foam.

[0111] According to another embodiment, a subject matter of the invention concerns the fiber foam as described above, wherein said fiber foam further comprises from 2.5% to 5.5% of weight of gelatin relative to the total weight of the fiber foam.

[0112] According to another embodiment, a subject matter of the invention concerns the fiber foam as described above comprising:

[0113] ■ 2.3% or 2.5% of weight of plasticizer (in particular glycerol) relative to the total weight of the fiber foam;

[0114] ■ 0.8% or 0.9% of weight of chitosan relative to the total weight of the fiber foam;

[0115] ■ 5.7% or 8.5% of weight of a foaming agent relative to the total weight of the fiber foam;

[0116] ■ 4.3% or 4.6% of weight of a binding agent relative to the total weight of the fiber foam;

[0117] ■ 64.7% or 69.5% of weight of water relative to the total weight of the fiber foam;

[0118] and

[0119] ■ 14.9% or 16.1% of weight of a fiber shred, the granulometry of which is less than or equal to 500 pm, relative to the total weight of the fiber foam, said fibershred comprising at least 50% of a fiber chosen among: textile fiber, cellulose fiber and their combination.

[0120] According to another embodiment, a subject matter of the invention concerns the fiber foam as described above, wherein said fiber foam comprises:

[0121] ■ 2.5% of weight of plasticizer (in particular glycerol) relative to the total weight of the fiber foam;

[0122] ■ 0.9% of weight of chitosan relative to the total weight of the fiber foam;

[0123] ■ 5.7% of weight of a foaming agent relative to the total weight of the fiber foam;

[0124] ■ 4.6% of weight of a binding agent relative to the total weight of the fiber foam;

[0125] ■ 69.5% of weight of water relative to the total weight of the fiber foam; and ■ 16.1% of weight of a fiber shred, the granulometry of which is less than or equal to 500 pm, relative to the total weight of the fiber foam, said fiber shred comprising at least 50% of a fiber chosen among: textile fiber, cellulose fiber and their combination.

[0126] According to another embodiment, a subject matter of the invention concerns the fiber foam as described above, wherein said fiber foam consists of:

[0127] ■ 2.5% of weight of plasticizer (in particular glycerol) relative to the total weight of the fiber foam;

[0128] ■ 0.9% of weight of chitosan relative to the total weight of the fiber foam;

[0129] ■ 0.7% of weight of acid (in particular acetic acid) relative to the total weight of the fiber foam;

[0130] ■ 5.7% of weight of a foaming agent relative to the total weight of the fiber foam;

[0131] ■ 4.6% of weight of a binding agent relative to the total weight of the fiber foam;

[0132] ■ 69.5% of weight of water relative to the total weight of the fiber foam; and ■ 16.1% of weight of a fiber shred, the granulometry of which is less than or equal to 500 pm, relative to the total weight of the fiber foam, said fiber shred comprising at least 50% of a fiber chosen among: textile fiber, cellulose fiber and their combination.

[0133] According to another embodiment, a subject matter of the invention concerns the fiber foam as described above, wherein said fiber foam comprises:

[0134] ■ 2.3% of weight of plasticizer (in particular glycerol) relative to the total weight of the fiber foam;■ 0.8% of weight of chitosan relative to the total weight of the fiber foam;

[0135] ■ 8.5% of weight of a foaming agent relative to the total weight of the fiber foam;

[0136] ■ 4.3% of weight of a binding agent relative to the total weight of the fiber foam;

[0137] ■ 64.7% of weight of water relative to the total weight of the fiber foam; and ■ 14.9% of weight of a fiber shred, the granulometry of which is less than or equal to 500 gm, relative to the total weight of the fiber foam, said fiber shred comprising at least 50% of a fiber chosen among: textile fiber, cellulose fiber and their combination.

[0138] According to another embodiment, a subject matter of the invention concerns the fiber foam as described above, wherein said fiber foam comprises:

[0139] ■ 2.3% of weight of plasticizer (in particular glycerol) relative to the total weight of the fiber foam;

[0140] ■ 0.8% of weight of chitosan relative to the total weight of the fiber foam;

[0141] ■ 0.6% of weight of acid (in particular acetic acid) relative to the total weight of the fiber foam;

[0142] ■ 8.5% of weight of a foaming agent relative to the total weight of the fiber foam;

[0143] ■ 4.3% of weight of a binding agent relative to the total weight of the fiber foam;

[0144] ■ 64.7% of weight of water relative to the total weight of the fiber foam; and ■ 14.9% of weight of a fiber shred, the granulometry of which is less than or equal to 500 pm, relative to the total weight of the fiber foam, said fiber shred comprising at least 50% of a fiber chosen among: textile fiber, cellulose fiber and their combination..

[0145] According to another embodiment, a subject matter of the invention concerns the fiber foam as described above, wherein said fiber foam consists of:

[0146] ■ 2.3% of weight of plasticizer (in particular glycerol) relative to the total weight of the fiber foam;

[0147] ■ 0.8% of weight of chitosan relative to the total weight of the fiber foam;

[0148] ■ 0.6% of weight of acid (in particular acetic acid) relative to the total weight of the fiber foam;

[0149] ■ 3.8% of weight of gelatin relative to the total weight of the fiber foam; ■ 8.5% of weight of a foaming agent relative to the total weight of the fiber foam;

[0150] ■ 4.3% of weight of a binding agent relative to the total weight of the fiber foam;■ 64.7% of weight of water relative to the total weight of the fiber foam; and ■ 14.9% of weight of a fiber shred, the granulometry of which is less than or equal to 500 gm, relative to the total weight of the fiber foam, said fiber shred comprising at least 50% of a fiber chosen among: textile fiber, cellulose fiber and their combination.

[0151] According to another embodiment, a subject matter of the invention concerns the fiber foam as described above, wherein said foaming agent is chosen among:

[0152] ■ vinyl alcohol (PVA) / polyvinyl acetate (PVAc) copolymers (or PVA / PVAc copolymer); and

[0153] ■ dishwashing products and foaming agent based on the following mixture:

[0154] grapes, liquorice roots, black tea and lemon (= Genfil®).

[0155] According to another embodiment, a subject matter of the invention concerns the fiber foam as described above, wherein said foaming agent is a dishwashing products or a foaming agent based on the following mixture: grapes, liquorice roots, black tea and lemon (= Genfil®). In particular, a subject matter of the invention concerns the fiber foam as described above, wherein said foaming agent is based on the following mixture: grapes, liquorice roots, black tea and lemon (= Genfil®). Advantageously, a subject matter of the invention concerns the fiber foam as described above, wherein said foaming agent is Genfil® (registered trademark of ARTRA IN§AAT PEYZAJ PLASTiK SANAYI VE TICARET LiMITED §IRKETi).

[0156] According to another embodiment, a subject matter of the invention concerns the fiber foam as described above, wherein said binding agent derives from polymeric sources and may be chosen among:

[0157] ■ polysaccharides such as starch-based glues, starch, xanthan gum, guar gum, cellulosic gum or alginate;

[0158] ■ proteins such as pectin and casein; and

[0159] ■ synthetic clay such as Laponite® (in particular Laponite® RD available on Mon- Droguiste.com).

[0160] According to another embodiment, a subject matter of the invention concerns the fiber foam as described above, wherein said binding agent is chosen among polysaccharides such as starch-based glues, starch, xanthan gum, guar gum, cellulosic gum or alginate. In particular, a subject matter of the invention concerns the fiber foam as described above, wherein said binding agentis starch. Advantageously, a subject matter of the invention concerns the fiber foam as described above, wherein said binding agent is maize starch.

[0161] According to another embodiment, a subject matter of the invention concerns the fiber foam as described above, wherein said binding agent is chosen among proteins such as pectin and casein. Advantageously, a subject matter of the invention concerns the fiber foam as described above, wherein said binding agent is pectin or casein

[0162] According to another embodiment, a subject matter of the invention concerns the fiber foam as described above, wherein said binding agent is chosen among synthetic clay such as Laponite® (in particular Laponite® RD available on Mon-Droguiste.com). Advantageously, a subject matter of the invention concerns the fiber foam as described above, wherein said binding agent is Laponite® (in particular Laponite® RD available on Mon-Droguiste.com).

[0163] According to another embodiment, a subject matter of the invention concerns the fiber foam as described above, wherein said fiber is textile fiber, in particular chosen among fiber of: cotton, linen, jute and viscose, said textile fiber may comprise from 0% to 100% of cellulose fiber.

[0164] “From 0% to 100% of cellulose fiber” means from 0% to 100%, from 0% to 95%, from 0% to 90%, from 0% to 85%, from 0% to 80%, from 0% to 75%, from 0% to 70%, from 0% to 65%, from 0% to 60%, from 0% to 55%, from 0% to 50%, from 0% to 45%, from 0% to 40%, from 0% to 35%, from 0% to 30%, from 0% to 25%, from 0% to 20%, from 0% to 15%, from 0% to 10%, from 0% to 5%,

[0165] from 5% to 100%, from 10% to 100%, from 15% to 100%, from 20% to 100%, from 25% to 100%, from 30% to 100%, from 35% to 100%, from 40% to 100%, from 45% to 100%, from 50% to 100%, from 55% to 100%, from 60% to 100%, from 65% to 100%, from 70% to 100%, from 75% to 100%, from 80% to 100%, from 85% to 100%, from 90% to 100%, from 95% to 100%, from 5% to 95%, from 10% to 90%, from 15% to 85%, from 20% to 80%, from 25% to 75%, from 30% to 70%, from 35% to 65%, from 40% to 60%, from 45% to 55% or from 50% to 55%. It also means that cellulose fiber may represent 0%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95% or 100% of textile fiber.

[0166] “Cellulose fiber” refers to fiber of printing paper; newsprint; glossy paper; cardboard; paper loaded with talc, non-woven paper; felt paper and blotting paper. The invention beingparticularly made of paper, said paper may come from wasted paper which can be recycled through the invention. Interestingly, coton fibers are almost entirely cellulose based.

[0167] According to another embodiment, a subject matter of the invention concerns the fiber foam as described above, wherein said fiber is cellulose fiber, in particular chosen among fiber of: printing paper; newsprint; glossy paper; cardboard; paper loaded with talc, non-woven paper; felt paper and blotting paper. Advantageously, a subject matter of the invention concerns the fiber foam as described above, wherein said fiber is chosen among fiber of: printing paper; newsprint; glossy paper; cardboard; paper loaded with talc, non-woven paper; felt paper and blotting paper.

[0168] According to a third aspect, a subject matter of the invention relates to a process for preparing the fiber foam as described above comprising at least the following steps:

[0169] a) mixing a homogenous pre-paste comprising water and:

[0170] - a homogeneous mill made with textile fiber and / or cellulose fiber with a granulometry less than or equal to 500 pm, or

[0171] - textile stripes and / or cellulose stripes (i.e. not reduced into said homogeneous mill),

[0172] with a homogenous solution comprising: a binding agent, a plasticizer (in particular glycerol) and water to obtain a homogenous paste;

[0173] b) mixing a chitosan solution with said homogenous paste and then stirring and blending them to obtain a blended paste; and

[0174] c) adding a foaming agent to said blended paste and then whisking them to obtain a fiber foam, the volume of which is at least 4 times higher than the volume of said blended paste.

[0175] According to a third aspect, a subject matter of the invention relates to a process for preparing the fiber foam as described above comprising at least the following steps:

[0176] a) wetting

[0177] - a homogeneous mill made with textile fiber and / or cellulose fiber with a granulometry less than or equal to 500 pm, or

[0178] - textile stripes and / or cellulose stripes (i.e. not reduced into said homogeneous mill),with water and then mixing them to obtain a homogenous pre-paste;

[0179] b) mixing said homogenous pre-paste with a homogenous solution comprising: a binding agent, a plasticizer (in particular glycerol) and water to obtain a homogenous paste;

[0180] c) mixing a chitosan solution with said homogenous paste and then stirring and blending them to obtain a blended paste; and

[0181] d) adding a foaming agent to said blended paste and then whisking them to obtain a fiber foam, the volume of which is at least 4 times higher than the volume of said blended paste.

[0182] According to this aspect, a subject matter of the invention also relates to a process for preparing the fiber foam as described above comprising at least the following steps:

[0183] a) reducing textile fiber and / or cellulose fiber in a shredder and then grinding it / them in a grain or laboratory mill to obtain a homogeneous mill of a granulometry less than or equal to 500 pm;

[0184] b) wetting said homogeneous mill with water and then mixing them to obtain a homogenous pre-paste;

[0185] c) mixing a binding agent and a plasticizer (in particular glycerol) to water to obtain a homogenous solution;

[0186] d) adding said homogenous solution to said homogenous pre-paste and then mixing them to obtain a homogenous paste (kitchen robot at full power for 1 min) e) dissolving chitosan in an aqueous solution of a pH comprised from 2 to 3 (in particular 0.5 M acetic acid) to obtain a chitosan solution;

[0187] f) adding said chitosan solution to said homogenous paste and then blending them to obtain a blended paste IOS+IOS using the hand-blender): and g) adding a foaming agent to said blended paste, the temperature of said blended paste being less than 25°C, and then whisking them to obtain a fiber foam, the volume of which is at least 4 times higher than the volume of said blended paste (kitchen robot at full power for 6-10 min, in particular 8 min).

[0188] According to this aspect, a subject matter of the invention also relates to a process for preparing the fiber foam as described above comprising at least the following steps:

[0189] a) reducing textile and / or cellulose in a shredder to obtain textile stripes and / or cellulose stripes;b) wetting said textile stripes and / or cellulose stripes with water and then mixing them to obtain a homogenous pre-paste;

[0190] c) mixing a binding agent and a plasticizer (in particular glycerol) to water to obtain a homogenous solution;

[0191] d) adding said homogenous solution to said homogenous pre-paste and then mixing them to obtain a homogenous paste (kitchen robot at full power for 1 min) e) dissolving chitosan in an aqueous solution of a pH comprised from 2 to 3 (in particular 0.5 M acetic acid) to obtain a chitosan solution;

[0192] f) adding said chitosan solution to said homogenous paste and then blending them to obtain a blended paste IOS+IOS using the hand-blender): and g) adding a foaming agent to said blended paste, the temperature of said blended paste being less than 25°C, and then whisking them to obtain a fiber foam, the volume of which is at least 4 times higher than the volume of said blended paste (kitchen robot at full power for 6-10 min, in particular 8 min).

[0193] “Cellulose” refers to fiber of printing paper; newsprint; glossy paper; cardboard; paper loaded with talc, non-woven paper; felt paper and blotting paper. Interestingly, coton fibers are almost entirely cellulose based.

[0194] “Textile” refers to cloth made of: cotton, linen, jute or viscose, said cloth may comprise from 0% to 100% of cellulose.

[0195] “Said blended paste, the temperature of said blended paste being less than 25°C” means that said blended paste is at a temperature comprised from 20°C to 24.5°C. “From 20°C to 24.5°C” means from 20°C to 24.5°C, from 20°C to 24°C, from 20°C to 23°C, from 20°C to 22°C, from 20°C to 21°C, from 21°C to 24.5°C, from 22°C to 24.5°C, from 23°C to 24.5°C, from 24°C to 24.5°C or from 22°C to 24°C. It also means that said homogenous paste is at a temperature of 20°C, 21°C, 22°C, 23°C, 24°C or 24.5°C.

[0196] “A fiber foam, the volume of which is at least 4 times higher than the volume of said blended paste” means that the volume of said fiber foam is at least 4 times higher than the volume of said blended paste. By “at least 4 times” it means at least 4 times, at least 5 times, at least 6 times, at least 7 times, at least 8 times, at least 9 times or at least 10 times. It also means that the volume of said fiber foam is from 4 to 10 times higher than the volume of said blendedpaste. “From 4 to 10 times” means from 4 to 5, from 4 to 6, from 4 to 7, from 4 to 8, from 4 to 9, from 4 to 10, from 5 to 10, from 6 to 10, from 7 to 10, from 8 to 10 or from 9 to 10.

[0197] According to another embodiment, a subject matter of the invention concerns the process for preparing the fiber foam as described above, wherein step d) is performed using a kitchen robot (e.g. Kitchenaid®, brand registered by WHIRLPOOL PROPERTIES, INC. CLASSIC OF 4.3L 5K45 S marketed) at full power (144 rpm ± 5) for 1 min.

[0198] According to another embodiment, a subject matter of the invention concerns the process for preparing the fiber foam as described above, wherein step g) is performed using a kitchen robot (e.g. Kitchenaid®, brand registered by WHIRLPOOL PROPERTIES, INC. CLASSIC OF 4.3L 5K45 S marketed) at full power (144 rpm ± 5) for 6-10 min, in particular 8 min. “For 6-10 min” means 6 min, 7 min, 8 min, 9 min or 10 min.

[0199] According to another embodiment, a subject matter of the invention concerns the process for preparing the fiber foam as described above, wherein:

[0200] ■ in step b), said homogeneous mill is added to water in a weight ratio to water of 1:1.48;

[0201] ■ in step c), said binding agent and said plasticizer (in particular glycerol) are added to water respectively in a weight ratio to water of 1 :5.17 and 1 :9.39; ■ in step f), said chitosan solution is added to said homogenous paste in a weight ratio to homogenous paste of 1 :2.98; and

[0202] ■ in step g), said foaming agent is added to said blended paste in a weight ratio to blended paste of 1 : 16.44.

[0203] According to another embodiment, a subject matter of the invention concerns the process for preparing the fiber foam as described above, wherein said fiber foam obtained further step g) comprises or consists of 16.1% by weight of paper homogenate (= homogenous mill), 5.7% by weight of foaming agent (in particular Genfil®), 4.6% by weight of binding agent, 0.9% by weight of chitosan, 0.7% by weight of acetic acid, 2.5% by weight of plasticizer (in particular glycerol) and 69.5% by weight of water with respect to the total weight of the fiber foam.

[0204] According to another embodiment, a subject matter of the invention concerns the process for preparing the fiber foam as described above, wherein said homogenous solution further comprises a step for preparing a jelly homogenous paste from said homogenous paste, said step being implemented between steps d) and e),said step comprising at least the following steps:

[0205] i. mixing gelatin to water, in particular in a weight ratio to water of 1:5.87, said water being heated at around 60°C, to obtain a jelly solution;

[0206] ii. cooling down said jelly solution to below 30°C before adding it to said homogenous paste and then mixing them to obtain a jelly homogenous paste (kitchen robot at full power for 1 min).

[0207] “Said water being heated at around 60°C” means that said water is heated to a temperature comprised from 58°C to 64°C. “From 58°C to 64°C” means from 58°C to 64°C, from 58°C to 63°C, from 58°C to 62°C, from 58°C to 61°C, from 59°C to 64°C, from 60°C to 64°C or from 60°C to 62°C. It also means that said water is heated at 58°C, 59°C, 60°C, 61°C, 62°C, 63°C or 64°C. Advantageously, said water is heated at 60°C.

[0208] “Cooling down said jelly solution to below 30°C” means that said jelly solution is cooled down to a temperature comprised from 20°C to 29.5°C. “From 20°C to 29.5°C” means from 20°C to 29.5°C, from 20°C to 29°C, from 20°C to 28°C, from 20°C to 27°C, from 20°C to 26°C, from 20°C to 25°C, from 20°C to 24°C, from 20°C to 23°C, from 20°C to 22°C, from 20°C to 21°C, from 21°C to 29.5°C, from 22°C to 29.5°C, from 23°C to 29.5°C, from 24°C to 29.5°C, from 25°C to 29.5°C, from 26°C to 29.5°C, from 27°C to 29.5°C, from 28°C to 29.5°C, from 29°C to 29.5°C, from 22°C to 28°C or from 24°C to 26°C. It also means that that said jelly solution is cooled down to 20°C, 21°C, 22°C, 23°C, 24°C, 25°C, 26°C, 27°C, 28°C, 29°C or 29.5°C.

[0209] According to another embodiment, a subject matter of the invention concerns the process for preparing the fiber foam as described above, wherein said fiber foam obtained further step g) comprises or consists of 14.9% by weight of paper homogenate (= homogenous mill), 8.5% by weight of foaming agent (in particular Genfil®), 4.3% by weight of binding agent, 0.8% by weight of chitosan, 0.6% by weight of acetic acid, 2.3% by weight of plasticizer (in particular glycerol), 3.8% by weight of gelatin and 64.7% of water with respect to the total weight of the fiber foam.

[0210] According to this third aspect, a subject matter of the invention concerns an alternative process for preparing the fiber foam as described above, said alternative process comprising at least the following steps:

[0211] a) wetting- a homogeneous mill made with textile fiber and / or cellulose fiber with a granulometry less than or equal to 500 gm, or

[0212] - textile stripes and / or cellulose stripes (i.e. not reduced into said homogeneous mill),

[0213] with water and then mixing them to obtain a homogenous pre-paste;

[0214] b) mixing said homogenous pre-paste with a binding agent and a plasticizer (in particular glycerol) to obtain a homogenous paste;

[0215] c) mixing gelatin to water, said water being heated at around 60°C, to obtain a jelly solution;

[0216] d) cooling down said jelly solution to below 30°C before adding it to said homogenous paste and then mixing them to obtain a jelly homogenous paste; e) mixing a chitosan solution with said jelly homogenous paste and then stirring and blending them to obtain a blended paste; and

[0217] f) adding a foaming agent to said blended paste and then whisking them to obtain a fiber foam, the volume of which is at least 4 times higher than the volume of said blended paste.

[0218] According to this aspect, a subject matter of the invention also relates to an alternative process for preparing the fiber foam as described above comprising at least the following steps:

[0219] a) reducing textile fiber and / or cellulose fiber in a shredder and then grinding it / them in a grain or laboratory mill to obtain a homogeneous mill of a granulometry less than or equal to 500 pm;

[0220] b) wetting said homogeneous mill with water and then mixing them to obtain a homogenous pre-paste;

[0221] c) mixing said homogenous pre-paste with a binding agent and a plasticizer (in particular glycerol) to obtain a homogenous paste (kitchen robot at full power for 1 min ,

[0222] d) mixing gelatin to water, said water being heated at around 60°C, to obtain a jelly solution;

[0223] e) cooling down said jelly solution to below 30°C before adding it to said homogenous paste and then mixing them to obtain a jelly homogenous paste (kitchen robot at full power for 1 min ,f) mixing a chitosan solution with said jelly homogenous paste and then stirring and blending them to obtain a blended paste IOS+IOS using the hand-blender): and

[0224] g) adding foaming agent to said blended paste and then whisking them to obtain a fiber foam, the volume of which is at least 4 times higher than the volume of said blended paste (kitchen robot at full power for 6-10 min, in particular 8 min).

[0225] According to this aspect, a subject matter of the invention also relates to an alternative process for preparing the fiber foam as described above comprising at least the following steps:

[0226] a) reducing textile and / or cellulose in a shredder to obtain textile stripes and / or cellulose stripes;

[0227] b) wetting said textile stripes and / or cellulose stripes with water and then mixing them to obtain a homogenous pre-paste;

[0228] c) mixing said homogenous pre-paste with a binding agent and a plasticizer (in particular glycerol) to obtain a homogenous paste (kitchen robot at full power for 1 min ,'

[0229] d) mixing gelatin to water, said water being heated at around 60°C, to obtain a jelly solution;

[0230] e) cooling down said jelly solution to below 30°C before adding it to said homogenous paste and then mixing them to obtain a jelly homogenous paste (kitchen robot at full power for 1 min ,'

[0231] f) mixing a chitosan solution with said jelly homogenous paste and then stirring and blending them to obtain a blended paste (IOs+IOs using the hand-blender),' and

[0232] g) adding foaming agent to said blended paste and then whisking them to obtain a fiber foam, the volume of which is at least 4 times higher than the volume of said blended paste (kitchen robot at full power for 6-10 min, in particular 8 min).

[0233] According to another embodiment, a subject matter of the invention concerns the alternative process for preparing the fiber foam as described above, wherein:

[0234] ■ in step b), said homogenous mill is added to water in a weight ratio to water of 1:1.48;■ in step c), said binding agent and said plasticizer (in particular glycerol) are added to said homogenous pre-paste in a weight ratio to homogenous pre-paste of 1:8.67 and 1:15.76 respectively;

[0235] ■ in step d), said gelatin is added to water in a weight ratio to water of 1 : 5.87; ■ in step e), said jelly solution is added to said homogenous paste in a weight ratio to homogenous paste of 1 : 1.69;

[0236] ■ in step f), said chitosan solution is added to said jelly homogenous paste in a weight ratio to jelly homogenous paste of 1:3.15;

[0237] ■ in step g), said foaming agent is added to said blended paste in a weight ratio to blended paste of 1:10.71.

[0238] According to another embodiment, a subject matter of the invention concerns the alternative process for preparing the fiber foam as described above, wherein step g) is performed using a kitchen robot (e.g. Kitchenaid®, brand registered by WHIRLPOOL PROPERTIES, INC. CLASSIC OF 4.3L 5K45 S marketed) at full power (144 rpm ± 5) for 6-10 min, in particular 8 min.

[0239] According to another embodiment, a subject matter of the invention concerns the alternative process for preparing the fiber foam as described above, wherein said fiber foam obtained further step e) comprises or consists of 14.9% by weight of paper homogenate (= homogenous mill), 8.5% by weight of foaming agent (in particular Genfil®), 4.3% by weight of binding agent, 0.8% by weight of chitosan, 0.6% by weight of acetic acid, 2.3% by weight of plasticizer (in particular glycerol), 3.8% by weight of gelatin and 64.7% of water with respect to the total weight of the fiber foam.

[0240] According to another aspect, a subject matter of the invention relates to a process for preparing a 3D printed fiber foam comprising at least the following steps:

[0241] a) charging a fiber foam according to the invention in its wetted state or a fiber foam obtainable by the process as described above in its wetted state in a 3D printing cartridge to obtain a charged 3D printing cartridge;

[0242] b) extruding from said charged 3D printing cartridge said fiber foam according to the invention in its wetted state or a fiber foam obtainable by the process as described above in its wetted state to obtain a wet 3D printed fiber foam; andc) drying said 3D printed fiber foam in its wetted state to obtain a 3D printed fiber foam in a dried state.

[0243] According to another aspect, a subject matter of the invention relates to a process for preparing a biocalcified fiber foam comprising at least the following steps:

[0244] a) infusing a fiber foam according to the invention in a dried state or a fiber foam obtainable by the process as described above in a dried state or a 3D printed fiber foam obtainable by the process as described above in a dried state with a bacterial solution for a period of at least 1 hour (e.g. Ih, 1.5h, 2hrs, 2.5hrs or 3hrs) to obtain an infused fiber foam,

[0245] said bacterial solution comprising a bacteria capable of microbial induced calcite precipitation, said bacteria being in particular Sporosarcina pasteurii, Bacillus arenosi, Sporosarcina urea, Brevibacterium ammoniagenes, Bacillus lentus, Proteus vulgaris, Myxococcus Xanthus or Helicobacter pylori,' b) removing said bacterial solution and subsequently infusing said infused fiber foam with a calcifying solution for a period of at least 24 hours (e.g. 24hrs, 25hrs, 26hrs, 27hrs; 28hrs, 29hrs or 30hrs) to obtain a twice-infused fiber foam, said calcifying solution being made of calcium, urea and water;

[0246] c) repeating steps a) and b) at least two times (e.g. 2 times, 3 times, 4 times, 5 times or 6 times) to obtain a biocalcified fiber foam in a wetted form; and d) drying said biocalcified fiber foam in its wetted state, in particular in a deshumidificated space, to obtain a biocalcified fiber foam in a dried state.

[0247] The process can be operated with a material in the form of a plate as well as 3D printed by pneumatic or mechanical extrusion completed by a biocalcification strategy induced by immersion or infusion.

[0248] According to another embodiment, a subject matter of the invention concerns the process as described above for preparing a biocalcified fiber foam, wherein said bacteria is chosen among: Sporosarcina pasteurii, Bacillus arenosi, Sporosarcina urea, Brevibacterium ammoniagenes, Bacillus lentus, Proteus vulgaris, Myxococcus Xanthus and Helicobacter pylori. Advantageously, a subject matter of the invention also concerns the process as described above for preparing a biocalcified fiber foam, wherein said bacteria is Sporosarcina pasteurii.According to another embodiment, a subject matter of the invention concerns the process as described above for preparing a biocalcified fiber foam, wherein said bacterial solution comprises or consists of 0.1-1.0% by weight of bacteria (preferably Sporosarcina pasleiirii).

[0249] 0.1-1.0% by weight of salt (table / sea salt of which the main component is sodium chloride) and 98.0-99.8% by weight of water with respect to the total weight of the bacterial solution.

[0250] According to another embodiment, a subject matter of the invention concerns the process as described above for preparing a biocalcified fiber foam, wherein said calcifying solution comprises or consists of 80.0-84.0% by weight of water, 5.0-7.0% by weight of urea and 11.0-13.0% by weight of calcium chloride with respect to the total weight of the calcifying solution.

[0251] According to another embodiment, a subject matter of the invention concerns the process as described above for preparing a biocalcified fiber foam, wherein step d) is performed in a deshumidificated space.

[0252] It has to be pointed out that when it is mentioned “dried state” it is referred to a state wherein the fiber foam according to the invention or a the biocalcified fiber foam according to the invention has lost its water content and has become a solid foam rather than a pasty liquid / foam. In particular, it means that the fiber foam according to the invention or a the biocalcified fiber foam according to the invention comprises from 0% to 10% of weight of water in relation to the total weight of the fiber foam according to the invention or a the biocalcified fiber foam according to the invention. So it can be from 0% to 2%, from 2% to 4%, from 4% to 8%, from 8% to 10% or from 2% to 8% or from 2% to 6% or from 4% to 8%. It should be noted that the fiber foam according to the invention or a the biocal cified fiber foam according to the invention is completely dried when this percentage of water is 0%.

[0253] According to another aspect, a subject matter of the invention relates to a process for preparing a 3D printed and biocalcified fiber foam comprising at least the steps of a process for preparing a 3D printed fiber foam as described above and then the steps of a process for preparing a biocal cified fiber foam as described above. Alternatively, this embodiment concerns a process for preparing a 3D printed fiber foam as described above further comprising the steps of a process for preparing a biocalcified fiber foam as described above in order to prepare a biocalcified fiber foam.According to another aspect, a subject matter of the invention relates to a biocalcified fiber foam obtainable by the process according to the invention.

[0254] According to the same aspect, a subject matter of the invention also relates to a biocal cified fiber foam comprising the fiber foam according to the invention, said biocalcified fiber foam comprising: oxygen, calcium, carbon and chlorine.

[0255] According to another embodiment, a subject matter of the invention concerns the biocal cified fiber foam as described above, wherein said biocalcified fiber foam is characterized by:

[0256] ■ pores having an average size from 10 pm to 250 pm and occupying a volume representing from 20% to 90% of the total volume of said biocalcified fiber foam;

[0257] ■ a density comprised from 0.3 g / cm3to 0.8 g / cm3;

[0258] ■ a flame-retardancy; and

[0259] ■ the fact that it is brittle.

[0260] According to another embodiment, a subject matter of the invention concerns the biocal cified fiber foam as described above, wherein said biocalcified fiber foam is characterized by:

[0261] ■ pores having an average size from 10 pm to 250 pm and occupying a volume representing from 20% to 90% of the total volume of said biocalcified fiber foam,

[0262] said size and volume of pore being digitally measured through the ImageJ software;

[0263] ■ a density comprised from 0.3 g / cm3to 0.8 g / cm3, said density being calculated according to the formula;

[0264] , mass ( q kq lb \

[0265] d = — - - = — or or — ;

[0266]

[0267] volume \crrv5m? fr5 /

[0268] ■ a flame-retardancy; and

[0269] ■ the fact that it is brittle.

[0270] “Pores having an average size from 10 pm to 250 pm” can therefore be from 10 pm to 20 pm, from 10 pm to 30 pm, from 10 pm to 40 pm, from 10 pm to 50 pm, from 10 pm to 60 pm, from 10 pm to 70 pm, from 10 pm to 80 pm, from 10 pm to 90 pm, from 10 pm to 100 pm, from 10 pm to 110 pm, from 10 pm to 120 pm, from 10 pm to 130 pm, from 10 pm to 140pm, from 10 pm to 150 pm, from 10 pm to 160 pm, from 10 pm to 170 pm, from 10 pm to 180 pm, from 10 pm to 190 pm, from 10 pm to 200 pm, from 10 pm to 210 pm, from 10 pm to 220 pm, from 10 pm to 230 pm, from 10 pm to 240 pm, from 10 pm to 250 pm, from 20 pm to 250 pm, from 30 pm to 250 pm, from 40 pm to 250 pm, from 50 pm to 250 pm, from 60 pm to 250 pm, from 70 pm to 250 pm, from 80 pm to 250 pm, from 90 pm to 250 pm, from 100 pm to 250 pm, from 110 pm to 250 pm, from 120 pm to 250 pm, from 130 pm to 250 pm, from 140 pm to 250 pm, from 150 pm to 250 pm, from 160 pm to 250 pm, from 170 pm to 250 pm, from 180 pm to 250 pm, from 190 pm to 250 pm, from 200 pm to 250 pm, from 210 pm to 250 pm, from 220 pm to 250 pm, from 230 pm to 250 pm, from 240 pm to 250 pm, from 50 pm to 200 pm, from 50 pm to 150 pm, from 50 pm to 100 pm, from 100 pm to 200 pm or from 150 pm to 200 pm. It also means that average size is of 10 gm, 20 gm, 30 gm, 40 gm, 50 gm, 60 gm, 70 gm, 80 gm, 90 gm, 100 gm, 110 gm, 120 gm, 130 gm, 140 gm, 150 gm, 160 gm, 170 gm, 180 gm, 190 gm, 200 gm, 210 gm, 220 gm, 230 gm, 240 gm or 250 gm.

[0271] “Pores occupying a volume representing from 20% to 90% of the total volume of said biocalcified fiber foam” means that said pores can therefore occupy 20% to 35%, 35% to 40%, 40% to 55%, 55% to 70%, 70% to 90% or even 35% to 80% or 40% to 70% of this total volume.

[0272] “Density comprised from 0.3 g / cm3to 0.8 g / cm3” means from 0.3 to 0.35 g / cm3, from 0.3 to 0.40 g / cm3, from 0.3 to 0.45 g / cm3, from 0.3 to 0.50 g / cm3, from 0.3 to 0.55 g / cm3, from 0.3 to 0.60 g / cm3, from 0.3 to 0.65 g / cm3, from 0.3 to 0.70 g / cm3, from 0.3 to 0.75 g / cm3, from 0.3 to 0.80 g / cm3, from 0.35 to 0.8 g / cm3, from 0.40 to 0.8 g / cm3, from 0.45 to 0.8 g / cm3, from 0.50 to 0.8 g / cm3, from 0.55 to 0.8 g / cm3, from 0.60 to 0.8 g / cm3, from 0.65 to 0.8 g / cm3, from 0.70 to 0.8 g / cm3, from 0.75 to 0.8 g / cm3, 0.4 g / cm3to 0.7 g / cm3or 0.5 g / cm3to 0.6 g / cm3. It also means that the density of the biocal cified fiber foam according to the invention is of 0.30 g / cm3, 0.35 g / cm3, 0.40 g / cm3, 0.45 g / cm3, 0.50 g / cm3, 0.55 g / cm3, 0.60 g / cm3, 0.65 g / cm3, 0.70 g / cm3, 0.75 g / cm3or 0.80 g / cm3.

[0273] “Flame-retardancy” refers to capacity of the biocalcified fiber foam according to the invention to slow down the spread of fire. It is evaluated as exemplified hereafter using the ISO standard 11925-2:2020 (Edition 4, 2020). According to another embodiment, a subject matter of the invention concerns the biocalcified fiber foam as described above, wherein said flame-retardancy is at least 5 min (from 5 min to 100 min).Interestingly, the biocalcified fiber foam according to the invention can be used for acoustic and thermal insulation, wall cladding, small lightweight furniture, partitions or space dividers or for other applications in interior architecture / decoration but also for packaging / protective packaging. While the hydrophilic nature of the material makes it unsuitable for outdoor use, a surface treatment could remedy this.

[0274] According to another embodiment, a subject matter of the invention concerns the biocal cified fiber foam as described above, wherein said biocalcified fiber foam is characterized by the fact that it does not produce cyanide gas or styrenic gas when laser cutting is used.

[0275] In any event, it should be noted that the various aspects of the invention, as well as the various embodiments thereof, are interdependent. These can therefore be combined with each other to obtain preferred aspects and / or embodiments of the invention not explicitly described. This is also true for the set of definitions provided in this description, which applies to all aspects of the invention and its embodiments.

[0276] Furthermore, the present invention is illustrated by, but not limited to, the following Figures and Examples.

[0277] LIST OF FIGURES

[0278] Figure 1. Photo of a paper foam sample based on chitosan before biocalcification obtained in Example No. 1.

[0279] Figures 2-4. Photos of a paper foam sample based on chitosan and gelatin before biocalcification obtained in Example No. 2.

[0280] Figures 5-6. Photos of a paper foam sample based on chitosan after biocalcification obtained in Example No. 1.

[0281] Figures 7-9. Photos of a paper foam sample based on chitosan and gelatin after biocalcification obtained in Example No. 2.

[0282] EXAMPLES EXAMPLE 1 -Paper foam as a sheet material including chitosanMATERIALS & EQUIPMENT

[0283] The paper foam resulted from the combination of paper fibers, the Genfil® herbal resin-based foaming agent, maize starch, plasticizer (in particular glycerol), chitosan powder, and tap water. While most raw materials were commercially available, however Chitosan powder was supplied by ALPHA-CHITIN a brand of COMGRAF sas France. To incorporate the chitosan powder needed to be diluted in a slightly acidic solution (0.5 M) using acetic acid. Later a 4% chitosan solution was prepared. The fibers were sourced and processed locally from waste generated at Ecole Nationale Superieure des Arts Decoratifs. The paper quality corresponded to discarded black and white printed paper copies ranging from 80 to 120 g that were sorted and shredded into stripes in a document shredder and finally processed for 40s+40s with a 1850W 28500rpm VEVOR grain Mill to obtain fine <0.5 mm paper fibers.

[0284] The foam was prepared using a domestic a 450W hand-held blender (SEB HT411) with double function blend and whisking. First, fibers and wet content pre-paste were blended and homogenated using a head tool with blade. Later, after adding the foaming agent, the mixture was whisked using the same device with proper whisking attachments. The whisking time extended to 8-10 min. The foam was then casted in a bespoke PL A rectangular- 3DP -based mould. The mould had a quadrangular shape 180 mm in length, 180 mm in width and 30 mm in height. It was designed to be divided into 3x3 matrix using bespoke 3DP dividers being then the smallest module of 60 mm length by 60 mm width and 30 mm height. The base plate was made with a frame-tensed batyline mesh fabric to facilitate a good air flow and speed up the foam drying time.

[0285] Methods

[0286] 1. 17.5 g of paper homogenate (= homogenous mill) was sprayed with 25.83 g of water (weight ratio to water 1:1.48). Then it was mixed all together to obtain a homogenous pre-paste.

[0287] 2. 5 g of maize starch, 2.75 g of glycerol (= plasticizer), 25.83 g of water (weight ratios to water 1:5.17; and 1:9.39 respectfully) were stirred together and added to the homogenous pre-paste to obtain a homogenous paste.

[0288] 3. 25.83 g of Chitosan solution is added to the homogenous paste (weight ratio to homogenous paste 1:2.98) and stirred well until it is homogeneous. This resulting paste is finally blended for IOS+IOS using the hand-blender to obtain a blended paste.

[0289] 4. 6.25 g of foaming agent was added to 102.74 g of the blended paste (weight ratio to homogenous paste 1:16.44), the temperature of which was less than 25°C, and thenwhisked using the hand-blend device at full speed for about 6-10 min, precisely 8 min, to obtain the foam, the volume of which was about 4 times higher than the volume of said blended paste. The foam was then immediately and gently transferred in the mould.

[0290] 5. The whole was let drying in a dedicated drying cupboard 1,000 mm wide, 2,000 mm height and 1,000 mm depth rack equipped with a dehumidifier (Aerian ADH20L).

[0291] Measurements

[0292] Length, width and height of samples were measured with a ruler to calculate the volume of the sample. A precision scale was used to weight the samples. These data were used to calculate the foam density according to the established formula:

[0293] mass / g kg lb \

[0294] d = — - - = — or — or

[0295]

[0296] volume \cm6m6ft6 /

[0297] Average size of the pores was digitally measured through the ImageJ software, by measuring the longest size and the shortest side of the pore, adding them together and then dividing this number by two.

[0298] RESULTS

[0299] A lightweight foamy sheet material made of entirely renewable and biodegradable resources was obtained (Figure 1). The sample presented a density of 0,0539g / cm3. The addition of chitosan extended the foam development as it retains better water content. It soaked in water quickly indicating a strong porosity or foam cell structure preservation. The sample stuck to the mould base plate and walls.

[0300] CONCLUSION

[0301] The high porous structure preservation showed relevant potential towards calcification.EXAMPLE 2 -Paper foam as a sheet material including chitosan and gelatin

[0302] MATERIALS & EQUIPMENT

[0303] The paper foam resulted from the combination of paper fibers, the Genfil® herbal resin-based foaming agent, maize starch, plasticizer (in particular glycerol), gelatin, chitosan powder, and tap water. While most raw materials were commercially available, however Chitosan powder was supplied by ALPHA-CHITIN a brand of COMGRAF sas France. To incorporate the chitosan powder needed to be diluted in a slightly acidic solution (0.5 M) using acetic acid. Later a 4% chitosan solution was prepared. The fibers were sourced and processed locally from waste generated at Ecole Nationale Superieure des Arts Decoratifs. The paper quality corresponded to discarded black and white printed paper copies ranging from 80 to 120 g that were sorted and shredded into stripes in a document shredder and finally processed for 40s+40s with a 1850W 28500rpm VEVOR grain Mill to obtain fine <0.5 mm paper fibers.

[0304] The foam was prepared using a domestic a 450W hand-held blender (SEB HT411) with double function blend and whisking. First, fibers and wet content pre-paste were blended and homogenated using a head tool with blade. Later, after adding the foaming agent the mixture was whisked using the same device with proper whisking attachments. The whisking time extended to 8-10 min. The foam was then casted in a bespoke PL A rectangular- 3DP -based mould. The mould had a quadrangular shape 180 mm in length, 180 mm in width and 30 mm in height. It was designed to be divided into 3x3 matrix using bespoke 3DP dividers being then the smallest module of 60 mm length by 60 mm width and 30 mm height. The base plate was made with a frame-tensed batyline mesh fabric to facilitate a good air flow and speed up the foam drying time.

[0305] Methods

[0306] 1. 17.5 g of paper homogenate (= homogenous mill) was sprayed with 25.83 g of water (weight ratio to water 1:1.48). Then it was mixed all together to obtain a homogenous pre-paste.

[0307] 2. 5 g of maize starch, 2.75 g of glycerol (= plasticizer) added to the homogenous pre-paste and stirred together to obtain a homogenous paste (weight ratio to homogenous prepaste 1:8.67 and 1:15.76 respectively).

[0308] 3. 4.4 g of gelatin and 25.83 g of water (weight ratios to water 1:5.87) were heated to dissolve the gelatin in a fine solution and set aside to rest and slightly cool down beforeadding it to the homogeneous paste (weight ratio to homogenous paste of 1:1.69) to obtain a jelly homogeneous paste.

[0309] 4. 25.83 g of Chitosan solution were added to the jelly homogeneous paste (weight ratio to jelly homogenous paste of 1:3.15) and stirred well until it is homogeneous. This resulting paste is finally blended for IOS+IOS using the hand-blender to obtain a blended paste.

[0310] 5. 10 g of foaming agent was added to 107.14 g of the blended paste (weight ratio to homogenous paste 1:10.71), the temperature of which was less than 25°C, and then whisked using the hand-blend device at full speed for about 6-10 min, precisely 8 min, to obtain the foam, the volume of which was about 4 times higher than the volume of said blended paste. The foam was then immediately and gently transferred in the mould.

[0311] 6. The whole was let drying in a dedicated drying cupboard 1,000 mm wide, 2,000 mm height and 1,000 mm depth rack equipped with a dehumidifier (Aerian ADH20L).

[0312] Measurements

[0313] Length, width and height of samples were measured with a ruler to calculate the volume of the sample. A precision scale was used to weight the samples. These data were used to calculate the foam density according to the established formula:

[0314] mass / g kg lb \

[0315] d = — - - = — or — or

[0316]

[0317] volume \cm6m6ft6 /

[0318] Average size of the pores was digitally measured through the ImageJ software, by measuring the longest size and the shortest side of the pore, adding them together and then dividing this number by two.

[0319] RESULTS

[0320] A lightweight foamy sheet material made of entirely renewable and biodegradable resources was obtained (Figures 2-4). The sample presented a density of 0,0864g / cm3. The addition of chitosan extended the foam development as it retains better water content. It soaked in water quickly indicating a strong porosity or foam cell structure preservation.

[0321] CONCLUSION

[0322] The high porous structure preservation showed relevant potential towards calcification.EXAMPLE 3 - Biocalcified paper foam example

[0323] MATERIALS & EQUIPMENT

[0324] The biocalcified foam resulted from the above-mentioned paper foam (see Examples No. 1 and 2) combined with bacterially induced calcite precipitation, occurring through hydrolysis when some bacteria were exposed to sources of calcium and urea. In this example, a sheet sample of 59x58x25 mm, in its dry state, was biocalcified (Figures 5-6 and 7-9). To do so, a freeze-dried Sporosarcina pasteurii bacterial strain and commercially available calcium chloride (90-98%) and urea in their solid form were used. Additionally, tap water and sodium chloride from table salt were used.

[0325] Methods

[0326] The sample was placed dry in a bespoke open-air bioreactor for infusion at room temperature (20°C-24°C) with two distinct solutions.

[0327] First, the artefact was infused with a bacterial solution (BS) composed of 0.1-1.0% by weight of Sporosarcina pasteurii, 0.1-1.0% by weight salt (table / sea salt of which the main component is sodium chloride) and 98.0-99.8% by weight of water with respect to the total weight of the bacterial solution to ensure that the bacterial colonies fully penetrate the sample. The BS was removed after about Ih.

[0328] The sample was then infused for 24hrs with the calcifying solution (CS) composed of 80.0-84.0% by weight water, 5.0-7.0% by weight urea and 11.0-13.0% by weight calcium chloride with respect to the total weight of the calcifying solution. After 24hrs the solution was removed. This process was repeated two subsequent times to obtain a full homogenous calcification throughout the whole sample. The sample was carefully taken out of the bioreactor and placed in a dehumidified space at room temperature (20°C-24°C) until fully dry.

[0329] RESULTS

[0330] A clear crystallization of the sample was obtained after three cycles of infusion. Sensory observation indicated a white, granular and more rigid texture clearly distinct from the material prior to biocalcification (Figures 5-6 and 7-9). No obvious distortion was detected to the naked eyes. Even measurement before / after biocalcification indicated a consolidation of prior volume of the artefact’s proportions gaining a bit of volume due to the thin calcite crust covering the whole surface. Final measures were 60x60x27 mm.During the biocalcification process itself, it was also observed that the infused foam was more stable, and less prone to deformation when exposed to the various solutions at stake in the biocalcification process.

[0331] CONCLUSION

[0332] The addition of chitosan in the foam formulation did not prevent biocalcification to occur. On the contrary, chitosan has facilitated the calcification process. This was probably because the sample fully dipped into water without further deterioration while also offering a high degree of porosity. Hence given form was kept after calcification.

[0333] EXAMPLE 4 - Flame-retardancy test

[0334] MATERIALS & EQUIPMENT

[0335] Biocalcified Paper foam samples from example No. 3 are used in this experiment. A kitchen blowtorch is used as a flame generator while the metal stand is tailor-made from a perforated metal plate. A Canon camera and a GoPro camera are simultaneously used to record the flammability and combustion of the materials over time.

[0336] Methods

[0337] To assess the flame retardancy of the biocalcified paper, it is created a testing apparatus akin to that used in the Single-Flame Source Test (ISO 11925). In the configuration used in the invention, a flame reaching approximately l,300°C is positioned at a 90° angle, with its edge maintained 40 mm away from the sample's edge. The sample is securely placed on a metal stand at a 45° angle. The flame is directed at the sample for one minute, and the progression of the flame is monitored for an additional five minutes after it is extinguished. The entire experiment is captured digitally as stop-motion images and recorded as .mp4 videos for recording flammability and combustion.

[0338] RESULTS

[0339] The biocalcified sample of the invention does not retain a flame after the initial ignition and shows no signs of afterglow or lingering flames; only a slight trace of combustion is observed at the edge, accompanied by minimal smoke during burning.CONCLUSION

[0340] This experiment demonstrates that biocalcification clearly prevents flammability in the aforementioned foam-based paper waste composites. It can therefore be considered as a relevant process to enhance flame retardancy without the use of chemicals that are harmful to human health.

[0341] EXAMPLE 5 - SEM EDX analysis

[0342] MATERIALS & EQUIPMENT

[0343] Small particles are extracted from biocalcified paper foam samples (see Example No. 3) with a cutter blade, then immobilised on sample stubs with carbon tape for SEM EDX analysis performed at Institut Pierre Gilles de Gennes’ technical platform with a Thermo Scientific Quattro ESEM system.

[0344] Methods

[0345] The specimen holders are exposed to nitrogen to remove floating particles of the samples and sputter-coated with a thin layer of gold coated prior to the analysis for better image / stability of the materials. Energy-dispersive X-ray analysis (EDX) is then applied along with SEM to analyse the types, and the quantity of elements present in the samples. The results are extracted from 2 different samples of biocal cified paper waste foam crafted as sheet material. 29 distinct points on those materials were selected for the analysis. Data are collected for each point as PowerPoint file, including the % of weight per element and the % of atoms.

[0346] SEM EDX analysis associates Scanning Electron Microscopy (SEM), which delivers high-resolution images of sample surfaces, with Energy Dispersive X-ray Spectroscopy (EDX) for the identification and quantification of elemental compositions. When the sample is struck by an electron beam in SEM, it emits characteristic X-rays that are detected by EDX, enabling concurrent morphological and chemical analysis at micro to nanoscale levels.

[0347] RESULTS

[0348] Results show that the biocal cified paper foam samples are constituted of Oxygen, Calcium, Chlorine and Carbon. Anecdotal traces of Sodium, Potassium, Gold, Aluminium, Iron, Magnesium and Sulfur are also found but not systematically.CONCLUSION

[0349] SEM EDX analysis reveals that the biocalcified paper foams are primarily constituted by oxygen, calcium, chlorine and carbon elements, which is consistent with the material resources and process used to craft these samples.

Claims

CLAIMS1. Use of plasticizer and chitosan to produce a fiber foam liable to be:■ 3D printed; or■ biocalcified using a bacteria capable of microbial induced calcite precipitation, said bacteria being in particular Sporosarcina pasteurii, Bacillus arenosi, Sporosarcina urea, Brevibacterium ammoniagenes, Bacillus lentus, Proteus vulgaris, Myxococcus Xanthus or Helicobacter pylori,' or■ 3D printed and then biocalcified using a bacteria capable of microbial induced calcite precipitation, said bacteria being in particular Sporosarcina pasteurii, Bacillus arenosi, Sporosarcina urea, Brevibacterium ammoniagenes, Bacillus lentus, Proteus vulgaris, Myxococcus Xanthus or Helicobacter pylori, wherein said fiber foam comprises:■ from 0.5% to 4.5% of weight of plasticizer (in particular glycerol) relative to the total weight of the fiber foam; and■ from 0.2% to 2.0% of weight of chitosan relative to the total weight of the fiber foam.

2. Use of plasticizer and chitosan according to claim 1, wherein said fiber foam further comprises from 4% to 10% of weight of a foaming agent relative to the total weight of the fiber foam.

3. Use of plasticizer and chitosan according to claim 1 or 2, wherein said fiber foam further comprises from 10% to 19% of weight of a fiber shred, the granulometry of which is less than or equal to 500 pm, relative to the total weight of the fiber foam, said fiber shred comprising at least 50% of a fiber chosen among: textile fiber, cellulose fiber and their combination.

4. Use of plasticizer and chitosan according to any of claims 1 to 3, wherein said fiber foam further comprises from 2% to 7% of weight of a binding agent relative to the total weight of the fiber foam.

5. Use of plasticizer and chitosan according to any of claims 1 to 4, wherein said fiber foam further comprises from 60% to 80% of weight of water relative to the total weight of the fiber foam.

6. Fiber foam comprising:■ from 0.5% to 4.5% of weight of plasticizer relative to the total weight of the fiber foam;■ from 0.2% to 2.0% of weight of chitosan relative to the total weight of the fiber foam;■ from 4% to 10% of weight of a foaming agent relative to the total weight of the fiber foam;■ from 2% to 7% of weight of a binding agent relative to the total weight of the fiber foam;■ from 60% to 80% of weight of water relative to the total weight of the fiber foam; and■ from 10% to 19% of weight of a fiber shred, the granulometry of which is less than or equal to 500 pm, relative to the total weight of the fiber foam, said fiber shred comprising at least 50% of a fiber chosen among: textile fiber, cellulose fiber and their combination.

7. Fiber foam according to claim 6 comprising:■ 2.3% or 2.5% of weight of plasticizer (in particular glycerol) relative to the total weight of the fiber foam;■ 0.8% or 0.9% of weight of chitosan relative to the total weight of the fiber foam;■ 5.7% or 8.5% of weight of a foaming agent relative to the total weight of the fiber foam;■ 4.3% or 4.6% of weight of a binding agent relative to the total weight of the fiber foam;■ 64.7% or 69.5% of weight of water relative to the total weight of the fiber foam;and■ 14.9% or 16.1% of weight of a fiber shred, the granulometry of which is less than or equal to 500 gm, relative to the total weight of the fiber foam, said fiber shred comprising at least 50% of a fiber chosen among: textile fiber, cellulose fiber and their combination.

8. Fiber foam according to claim 6 or 7, wherein said foaming agent is chosen among:■ vinyl alcohol (PVA) / polyvinyl acetate (PVAc) copolymers (or PVA / PVAc copolymer); and■ dishwashing products and foaming agent based on the following mixture:grapes, liquorice roots, black tea and lemon (= Genfil®).

9. Fiber foam according to any of claims 6 to 8, wherein said binding agent derives from polymeric sources and may be chosen among:■ polysaccharides such as starch-based glues, starch, xanthan gum, guar gum, cellulosic gum or alginate;■ proteins such as pectin and casein; and■ synthetic clay such as Laponite®.

10. Fiber foam according to any of claims 6 to 9, wherein said fiber is textile fiber, in particular chosen among fiber of: cotton, linen, jute and viscose,said textile fiber may comprise from 0% to 100% of cellulose fiber.

11. Fiber foam according to any of claims 6 to 11, wherein said fiber is cellulose fiber, in particular chosen among fiber of: printing paper; newsprint; glossy paper; cardboard; paper loaded with talc, non-woven paper; felt paper and blotting paper.

12. Process for preparing the fiber foam according to any of claims 6 to 11 comprising at least the following steps:a) mixing a homogenous pre-paste comprising water and:- a homogeneous mill made with textile fiber and / or cellulose fiber with a granulometry less than or equal to 500 pm, or- textile stripes and / or cellulose stripes (i.e. not reduced into said homogeneous mill),with a homogenous solution comprising: a binding agent, a plasticizer (in particular glycerol) and water to obtain a homogenous paste;b) mixing a chitosan solution with said homogenous paste and then stirring and blending them to obtain a blended paste; and c) adding a foaming agent to said blended paste and then whisking them to obtain a fiber foam, the volume of which is at least 4 times higher than the volume of said blended paste.

13. Process for preparing a 3D printed fiber foam comprising at least the following steps:a) charging a fiber foam according to any of claims 6 to 11 in its wetted state or a fiber foam obtainable by the process according to claim 12 in its wetted state in a 3D printing cartridge to obtain a charged 3D printing cartridge; b) extruding from said charged 3D printing cartridge said fiber foam according to any of claims 6 to 11 in its wetted state or a fiber foam obtainable by the process according to claim 12 in its wetted state to obtain a wet 3D printed fiber foam; andc) drying said 3D printed fiber foam in its wetted state to obtain a 3D printed fiber foam in a dried state.

14. Process for preparing a biocalcified fiber foam comprising at least the following steps:a) infusing a fiber foam according to any of claims 6 to 11 in a dried state or a fiber foam obtainable by the process according to claim 12 in a dried state or a 3D printed fiber foam obtainable by the process according to claim 10 in a driedstate with a bacterial solution for a period of at least 1 hour to obtain an infused fiber foam,said bacterial solution comprising a bacteria capable of microbial induced calcite precipitation, said bacteria being in particular Sporosarcina pasteurii, Bacillus arenosi, Sporosarcina urea, Brevibacterium ammoniagenes, Bacillus lentus, Proteus vulgaris, Myxococcus Xanthus or Helicobacter pylori,' b) removing said bacterial solution and subsequently infusing said infused fiber foam with a calcifying solution for a period of at least 24 hours to obtain a twice- infused fiber foam,said calcifying solution being made of calcium, urea and water;c) repeating steps a) and b) at least two times to obtain a biocalcified fiber foam in a wetted form; andd) drying said biocalcified fiber foam in its wetted state, in particular in a deshumidificated space, to obtain a biocalcified fiber foam in a dried state.

15. Process for preparing a 3D printed fiber foam according to claim 13 further comprising the steps of a process according to claim 14 in order to prepare a biocalcified fiber foam.

16. Biocalcified fiber foam obtainable by the process according to claim 14 or 15.

17. Biocalcified fiber foam comprising the fiber foam according to any of claims 6 to 11, said biocalcified fiber foam comprising: oxygen, calcium, carbon and chlorine.

18. Biocalcified fiber foam according to claim 17, wherein said biocal cified fiber foam is characterized by:■ pores having an average size from 10 pm to 250 pm and occupying a volume representing from 20% to 90% of the total volume of said biocalcified fiber foam,said size and volume of pore being digitally measured through the ImageJ software;■ a density comprised from 0.3 g / cm3to 0.8 g / cm3, said density being calculated according to the formula;, mass ( q kq lb \d = — - - = — or or — ;volume \crrv5m? fr5 / ■ a flame-retardancy; and■ the fact that it is brittle.

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