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Rostami, J. (2024). Functional Low-Density Materials from Cellulose Fibers and Fibrils. (Doctoral dissertation). Stockholm: Kungliga Tekniska högskolan
Open this publication in new window or tab >>Functional Low-Density Materials from Cellulose Fibers and Fibrils
2024 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Cellulose-based aerogels are emerging bio-based materials for a range of applications in the quest toward a circular and carbon-neutral society. Owing to their lightweight nature, high porosity, high specific surface area, biocompatibility, and biodegradability, cellulose aerogels are suitable for packaging, insulation, wound care products, hygiene products, and water purification. However, their commercial use is hampered by complicated time- and energy-consuming fabrication processes. Hence, industrially relevant processes with upscaling opportunities need to be developed for cellulose-based aerogels to reach their full potential. 

This thesis explores different scalable and simple methods for preparing and designing highly porous aerogels with high wet integrity using cellulose-rich fibers and cellulose nanofibrils (CNFs). As wet integrity is crucial for specific applications and enables further functionalization of the aerogels using water-based chemistry, different methods were developed to achieve wet integrity without complicated crosslinking procedures. The effects of the raw materials and processing methods on the final material properties were also carefully studied to optimize the performance for the targeted applications. Moreover, the role of the network-forming ability of CNFs in the development of functional materials with structural integrity was explored by incorporating small amounts of CNFs in aerogel systems based on macroscopic cellulose-rich fibers and nanosized metal-organic frameworks. 

Finally, the potential of the different developed cellulose-based or cellulose-reinforced aerogels with high wet integrity was demonstrated in applications for which the aerogels’ structural integrity and physical and mechanical properties are highly advantageous, such as biomedical applications, gas storage and separation, flame retardancy, and hygiene products. As demonstrated in this thesis, these functional aerogel materials could be a bio-based alternative for today’s fossil-based materials. 

Abstract [sv]

Cellulosabaserade aerogeler har på senare tid visat sig vara användbara biobaserade material för olika tillämpningar i strävan mot ett cirkulärt och kolneutralt samhälle. Materialens mycket låga densitet, höga porositet, höga specifika yta, biokompatibilitet och biologiska nedbrytbarhet innebär att cellulosaaerogeler är lämpliga för förpackningar, isolering, sårvårdsprodukter, hygienprodukter och vattenrening. Den kommersiella användningen har dock bromsats av komplicerade, tid- och energikrävande tillverkningsmetoder. Därmed måste industriellt relevanta processer med uppskalningsmöjligheter utvecklas för att cellulosabaserade aerogeler ska nå sin fulla potential. 

Denna avhandling utforskar olika skalbara och enkla metoder för att bereda och skräddarsy högporösa och våtstabila aerogeler från cellulosafibrer och cellulosananofibriller (CNFer). Eftersom våtstabilitet är avgörande för vissa tillämpningar och möjliggör ytterligare funktionalisering med vattenbaserad kemi, har ett omfattande arbete genomförts för att identifiera nya metoder för att skapa en god våtstabilitet utan att använda komplicerade tvärbindningsprocedurer. Ett stort fokus har även lagts på att klarlägga råvarans och bearbetningsmetodernas inverkan på de slutliga materialegenskaperna för att optimera prestandan för riktade tillämpningar. Dessutom har CNFers unika nätverksbildande egenskaper också utforskats i att skapa funktionella material med strukturell integritet från mycket små mängder CNFer i aerogelsystem baserade på makroskopiska cellulosarika fibrer och nanopartiklar av metallorganiska nätverk.

Slutligen demonstrerades potentialen av de framställda cellulosabaserade och cellulosaförstärkta aerogelerna med utmärkt våtstyrka i tillämpningar där deras strukturella integritet, fysikaliska och mekaniska egenskaper kan användas på ett mycket fördelaktigt sätt, till exempel biomedicinska applikationer, gaslagring och -separering, flamskydd, och hygienprodukter. Mot bakgrund av dessa resultat är det alltså rimligt att slå fast att dessa funktionella aerogeler kan utgöra möjliga biobaserade alternativ till dagens fossilbaserade material.

Place, publisher, year, edition, pages
Stockholm: Kungliga Tekniska högskolan, 2024. p. 70
Series
TRITA-CBH-FOU ; 2024:20
Keywords
Aerogel, cellulose, nanotechnology, wood, fibers, nanofibrils, microfibrils, functional materials, bio-based, wet integrity, metal-organic frameworks, Aerogel, cellulosa, nanoteknologi, trä, fibrer, nanofibriller, mikrofibriller, funktionella material, biobaserad, våtstyrka, metallorganiska nätverk
National Category
Paper, Pulp and Fiber Technology
Research subject
Fibre and Polymer Science
Identifiers
urn:nbn:se:kth:diva-346652 (URN)978-91-8040-933-9 (ISBN)
Public defence
2024-06-14, D1, Lindstedtsvägen 9, https://kth-se.zoom.us/j/63426784337, Stockholm, 10:00 (English)
Opponent
Supervisors
Funder
Swedish Research Council
Note

QC 20240522

Embargo godkänt av skolchef Amelie Eriksson Karlström via e-post 2024-05-14

Available from: 2024-05-22 Created: 2024-05-21 Last updated: 2024-05-23Bibliographically approved
Östmans, R., Benselfelt, T., Erlandsson, J., Rostami, J., Hall, S., Lindström, S. B. & Wågberg, L. (2024). Solidified water at room temperature hosting tailored fluidic channels by using highly anisotropic cellulose nanofibrils. Materials Today Nano, 26, Article ID 100476.
Open this publication in new window or tab >>Solidified water at room temperature hosting tailored fluidic channels by using highly anisotropic cellulose nanofibrils
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2024 (English)In: Materials Today Nano, E-ISSN 2588-8420, Vol. 26, article id 100476Article in journal (Refereed) Published
Abstract [en]

Highly anisotropic cellulose nanofibrils can solidify liquid water, creating self-supporting structures by incorporating a tiny number of fibrils. These fibrillar hydrogels can contain as much as 99.99 wt% water. The structure and mechanical properties of fibrillar networks have so far not been completely understood, nor how they solidify the bulk water at such low particle concentrations. In this work, the mechanical properties of cellulose fibrillar hydrogels in the dilute regime from a wt% perspective have been studied, and an elastoplastic model describing the network structure and its mechanics is presented. A significant insight from this work is that the ability of the fibrils to solidify water is very dependent on particle stiffness and the number of contact points it can form in the network structure. The comparison between the experimental results and the theoretical model shows that the fibrillar networks in the dilute regime form via a non-stochastic process since the fibrils have the time and freedom to find contact points during network formation by translational and rotational diffusion. The formed, dilute fibrillar network deforms by sliding fibril contacts upon straining the network beyond its elastic limit. Our results also show that before macroscopic failure, the fibril contacts are restored once the load is released. The exceptional properties of this solidified water are exploited to host fluidic channels, allowing directed fluid transportation in water. Finally, the microfluidic channels formed in the hydrogels are tailored by the layer-by-layer technique to be interactive against external stimuli, a characteristic envisioned to be useful in biomedical applications.

Place, publisher, year, edition, pages
Elsevier BV, 2024
Keywords
Cellulose nanofibrils, Channels, Colloidal gel, Fibrillar hydrogels, Layer-by-layer, Network model
National Category
Materials Engineering
Identifiers
urn:nbn:se:kth:diva-345750 (URN)10.1016/j.mtnano.2024.100476 (DOI)2-s2.0-85189942008 (Scopus ID)
Note

QC 20240424

Available from: 2024-04-18 Created: 2024-04-18 Last updated: 2024-04-29Bibliographically approved
Wang, Z., Heasman, P., Rostami, J., Benselfelt, T., Linares, M., Li, H., . . . Wågberg, L. (2023). Dynamic Networks of Cellulose Nanofibrils Enable Highly Conductive and Strong Polymer Gel Electrolytes for Lithium-Ion Batteries. Advanced Functional Materials, 33(30), Article ID 2212806.
Open this publication in new window or tab >>Dynamic Networks of Cellulose Nanofibrils Enable Highly Conductive and Strong Polymer Gel Electrolytes for Lithium-Ion Batteries
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2023 (English)In: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 33, no 30, article id 2212806Article in journal (Refereed) Published
Abstract [en]

Tunable dynamic networks of cellulose nanofibrils (CNFs) are utilized to prepare high-performance polymer gel electrolytes. By swelling an anisotropically dewatered, but never dried, CNF gel in acidic salt solutions, a highly sparse network is constructed with a fraction of CNFs as low as 0.9%, taking advantage of the very high aspect ratio and the ultra-thin thickness of the CNFs (micrometers long and 2–4 nm thick). These CNF networks expose high interfacial areas and can accommodate massive amounts of the ionic conductive liquid polyethylene glycol-based electrolyte into strong homogeneous gel electrolytes. In addition to the reinforced mechanical properties, the presence of the CNFs simultaneously enhances the ionic conductivity due to their excellent strong water-binding capacity according to computational simulations. This strategy renders the electrolyte a room-temperature ionic conductivity of 0.61 ± 0.12 mS cm−1 which is one of the highest among polymer gel electrolytes. The electrolyte shows superior performances as a separator for lithium iron phosphate half-cells in high specific capacity (161 mAh g−1 at 0.1C), excellent rate capability (5C), and cycling stability (94% capacity retention after 300 cycles at 1C) at 60 °C, as well as stable room temperature cycling performance and considerably improved safety compared with commercial liquid electrolyte systems.

Place, publisher, year, edition, pages
Wiley, 2023
Keywords
cellulose nanofibrils, composites, energy storages, lithium-ion batteries, polymer electrolytes
National Category
Materials Chemistry Polymer Chemistry
Identifiers
urn:nbn:se:kth:diva-338472 (URN)10.1002/adfm.202212806 (DOI)000973324900001 ()2-s2.0-85152801974 (Scopus ID)
Note

QC 20231115

Available from: 2023-11-15 Created: 2023-11-15 Last updated: 2023-11-15Bibliographically approved
Östmans, R., Cortes Ruiz, M. F., Rostami, J., Sellman, F. A., Wågberg, L., Lindström, S. B. & Benselfelt, T. (2023). Elastoplastic behavior of anisotropic, physically crosslinked hydrogel networks comprising stiff, charged fibrils in an electrolyte. Soft Matter, 19(15), 2792-2800
Open this publication in new window or tab >>Elastoplastic behavior of anisotropic, physically crosslinked hydrogel networks comprising stiff, charged fibrils in an electrolyte
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2023 (English)In: Soft Matter, ISSN 1744-683X, E-ISSN 1744-6848, Vol. 19, no 15, p. 2792-2800Article in journal (Refereed) Published
Abstract [en]

Fibrillar hydrogels are remarkably stiff, low-density networks that can hold vast amounts of water. These hydrogels can easily be made anisotropic by orienting the fibrils using different methods. Unlike the detailed and established descriptions of polymer gels, there is no coherent theoretical framework describing the elastoplastic behavior of fibrillar gels, especially concerning anisotropy. In this work, the swelling pressures of anisotropic fibrillar hydrogels made from cellulose nanofibrils were measured in the direction perpendicular to the fibril alignment. This experimental data was used to develop a model comprising three mechanical elements representing the network and the osmotic pressure due to non-ionic and ionic surface groups on the fibrils. At low solidity, the stiffness of the hydrogels was dominated by the ionic swelling pressure governed by the osmotic ingress of water. Fibrils with different functionality show the influence of aspect ratio, chemical functionality, and the remaining amount of hemicelluloses. This general model describes physically crosslinked hydrogels comprising fibrils with high flexural rigidity - that is, with a persistence length larger than the mesh size. The experimental technique is a framework to study and understand the importance of fibrillar networks for the evolution of multicellular organisms, like plants, and the influence of different components in plant cell walls.

Place, publisher, year, edition, pages
Royal Society of Chemistry (RSC), 2023
National Category
Polymer Chemistry
Identifiers
urn:nbn:se:kth:diva-330921 (URN)10.1039/d2sm01571d (DOI)000960684700001 ()36992628 (PubMedID)2-s2.0-85152114916 (Scopus ID)
Note

QC 20230704

Available from: 2023-07-04 Created: 2023-07-04 Last updated: 2024-04-29Bibliographically approved
Rostami, J., Benselfelt, T., Maddalena, L., Avci, C., Sellman, F. A., Ciftci, G. C., . . . Wågberg, L. (2022). Shaping 90 wt% NanoMOFs into Robust Multifunctional Aerogels Using Tailored Bio-Based Nanofibrils. Advanced Materials, 34(38), Article ID 2204800.
Open this publication in new window or tab >>Shaping 90 wt% NanoMOFs into Robust Multifunctional Aerogels Using Tailored Bio-Based Nanofibrils
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2022 (English)In: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 34, no 38, article id 2204800Article in journal (Refereed) Published
Abstract [en]

Metal–organic frameworks (MOFs) are hybrid porous crystalline networks with tunable chemical and structural properties. However, their excellent potential is limited in practical applications by their hard-to-shape powder form, making it challenging to assemble MOFs into macroscopic composites with mechanical integrity. While a binder matrix enables hybrid materials, such materials have a limited MOF content and thus limited functionality. To overcome this challenge, nanoMOFs are combined with tailored same-charge high-aspect-ratio cellulose nanofibrils (CNFs) to manufacture robust, wet-stable, and multifunctional MOF-based aerogels with 90 wt% nanoMOF loading. The porous aerogel architectures show excellent potential for practical applications such as efficient water purification, CO2 and CH4 gas adsorption and separation, and fire-safe insulation. Moreover, a one-step carbonization process enables these aerogels as effective structural energy-storage electrodes. This work exhibits the unique ability of high-aspect-ratio CNFs to bind large amounts of nanoMOFs in structured materials with outstanding mechanical integrity—a quality that is preserved even after carbonization. The demonstrated process is simple and fully discloses the intrinsic potential of the nanoMOFs, resulting in synergetic properties not found in the components alone, thus paving the way for MOFs in macroscopic multifunctional composites. 

Place, publisher, year, edition, pages
Wiley, 2022
Keywords
aerogels, cellulose nanofibrils, flame retardancy, gas adsorption and separation, metal–organic frameworks, supercapacitors, water purification, Aspect ratio, Carbonization, Crystalline materials, Gas adsorption, Hybrid materials, Nanocellulose, Nanofibers, Supercapacitor, Bio-based, Crystalline networks, Flame-retardancy, Gas adsorption and separations, High aspect ratio, Mechanical integrity, Metalorganic frameworks (MOFs), Nano-fibrils, Binders, Composites, Loading, Materials, Powder, Processes
National Category
Materials Chemistry
Identifiers
urn:nbn:se:kth:diva-326793 (URN)10.1002/adma.202204800 (DOI)000840897400001 ()35906189 (PubMedID)2-s2.0-85135930335 (Scopus ID)
Note

QC 20230515

Available from: 2023-05-15 Created: 2023-05-15 Last updated: 2024-05-21Bibliographically approved
Rostami, J., Gordeyeva, K., Benselfelt, T., Lahchaichi, E., Hall, S. A., Riazanova, A., . . . Wågberg, L. (2021). Hierarchical build-up of bio-based nanofibrous materials with tunable metal-organic framework biofunctionality. Materials Today, 48, 47-58
Open this publication in new window or tab >>Hierarchical build-up of bio-based nanofibrous materials with tunable metal-organic framework biofunctionality
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2021 (English)In: Materials Today, ISSN 1369-7021, E-ISSN 1873-4103, Vol. 48, p. 47-58Article in journal (Refereed) Published
Abstract [en]

Multifunctional, light-weight, responsive materials show promise in a range of applications including soft robotics, therapeutic delivery, advanced diagnostics and charge storage. This paper presents a novel, scalable, efficient and sustainable approach for the preparation of cellulose nanofibril-based aerogels via a facile ice-templating, solvent exchange and air-drying procedure, which could replace existing inefficient drying processes. These ambient-dried aerogels (similar to 99% porosity) exhibit a high specific compressive modulus (26.8 +/- 6.1 kPa m(3) kg(-1), approaching equivalence of carbon-nanotubereinforced aerogels), wet stability and shape recovery (80-90%), favorable specific surface area (90 m(2) g(-1)) and tunable densities (2-20 kg m(-3)). The aerogels provide an ideal nanofibrillar substrate for in-situ growth of metal-organic frameworks (MOFs), via co-assembly of MOF precursors with proteins in aqueous solutions. The resulting hybrid aerogels show a nine-fold increase in surface area (810 m(2)g(-1)), with preserved wet stability and additional protein biofunctionality. The hybrid aerogels facilitate a pH-controlled release of immobilized proteins, following a concomitant disassembly of the surface grown MOFs, demonstrating their use in controlled delivery systems. The colorimetric protein binding assay of the biofunctionalized hybrid aerogel also demonstrates the potential of the material as a novel 3D bioassay platform, which could potentially be an alternative to plate-based enzyme-linked immunosorbent assay.

Place, publisher, year, edition, pages
Elsevier BV, 2021
Keywords
3D lightweight materials, Aerogels, Cellulose nanofibrils, Metal-organic frameworks, Controlled release, Protein binding assay
National Category
Materials Chemistry Paper, Pulp and Fiber Technology Polymer Chemistry
Identifiers
urn:nbn:se:kth:diva-305086 (URN)10.1016/j.mattod.2021.04.013 (DOI)000711373200009 ()2-s2.0-85106632112 (Scopus ID)
Note

QC 20211123

Available from: 2021-11-23 Created: 2021-11-23 Last updated: 2024-05-21Bibliographically approved
Navarro, J. R., Rostami, J., Ahlinder, A., Mietner, J. B., Bernin, D., Saake, B. & Edlund, U. (2020). Surface-Initiated Controlled Radical Polymerization Approach to in Situ Cross-Link Cellulose Nanofibrils with Inorganic Nanoparticles. Biomacromolecules, 21(5), 1952-1961
Open this publication in new window or tab >>Surface-Initiated Controlled Radical Polymerization Approach to in Situ Cross-Link Cellulose Nanofibrils with Inorganic Nanoparticles
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2020 (English)In: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 21, no 5, p. 1952-1961Article in journal (Refereed) Published
Abstract [en]

This paper investigates a strategy to convert hydrophilic cellulose nanofibrils (CNF) into a hydrophobic highly cross-linked network made of cellulose nanofibrils and inorganic nanoparticles. First, the cellulose nanofibrils were chemically modified through an esterification reaction to produce a nanocellulose-based macroinitiator. Barium titanate (BaTiO3, BTO) nanoparticles were surface-modified by introducing a specific monomer on their outer-shell surface. Finally, we studied the ability of the nanocellulose-based macroinitiator to initiate a single electron transfer living radical polymerization of stearyl acrylate (SA) in the presence of the surface-modified nanoparticles. The BTO nanoparticles will transfer new properties to the nanocellulose network and act as a cross-linking agent between the nanocellulose fibrils, while the monomer (SA) directly influences the hydrophilic-lipophilic balance. The pristine CNF and the nanoparticle cross-linked CNF are characterized by FTIR, SEM, and solid-state 13C NMR. Rheological and dynamic mechanical analyses revealed a high dregee of cross-linking.

Place, publisher, year, edition, pages
American Chemical Society (ACS), 2020
National Category
Chemical Sciences
Identifiers
urn:nbn:se:kth:diva-276390 (URN)10.1021/acs.biomac.0c00210 (DOI)000535186300029 ()32223221 (PubMedID)2-s2.0-85084721299 (Scopus ID)
Note

QC 20200616

Available from: 2020-06-16 Created: 2020-06-16 Last updated: 2022-06-26Bibliographically approved
Rostami, J., Mathew, A. P. & Edlund, U. (2019). Zwitterionic acetylated cellulose nanofibrils. Molecules, 24(17), Article ID 3147.
Open this publication in new window or tab >>Zwitterionic acetylated cellulose nanofibrils
2019 (English)In: Molecules, ISSN 1431-5157, E-ISSN 1420-3049, Vol. 24, no 17, article id 3147Article in journal (Refereed) Published
Abstract [en]

A strategy is devised to synthesize zwitterionic acetylated cellulose nanofibrils (CNF). The strategy included acetylation, periodate oxidation, Schiff base reaction, borohydride reduction, and a quaternary ammonium reaction. Acetylation was performed in glacial acetic acid with a short reaction time of 90 min, yielding, on average, mono-acetylated CNF with hydroxyl groups available for further modification. The products from each step were characterized by FTIR spectroscopy, ζ-potential, SEM-EDS, AFM, and titration to track and verify the structural changes along the sequential modification route.

Place, publisher, year, edition, pages
MDPI AG, 2019
Keywords
Acetylation, Cellulose nanofibrils, CNF, Zwitterionic
National Category
Biochemistry and Molecular Biology
Identifiers
urn:nbn:se:kth:diva-262515 (URN)10.3390/molecules24173147 (DOI)000488613700127 ()31470598 (PubMedID)2-s2.0-85071698675 (Scopus ID)
Note

QC 20191028

Available from: 2019-10-29 Created: 2019-10-29 Last updated: 2024-03-15Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-2489-8439

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