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Sepahvand, S., Jonoobi, M., Ashori, A., Gauvin, F., Brouwers, H., Oksman, K. & Yu, Q. (2020). A promising process to modify cellulose nanofibers for carbon dioxide (CO2) adsorption. Carbohydrate Polymers, 230, Article ID 115571.
Open this publication in new window or tab >>A promising process to modify cellulose nanofibers for carbon dioxide (CO2) adsorption
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2020 (English)In: Carbohydrate Polymers, ISSN 0144-8617, E-ISSN 1879-1344, Vol. 230, article id 115571Article in journal (Refereed) Published
Abstract [en]

A novel process of using phthalimide to modify cellulose nanofibers (CNF) for CO2 adsorption was studied. The effectiveness of the modification was confirmed by ATR-IR. Phthalimide incorporation onto CNF was confirmed with the characteristic peaks of NH2, C–N, and ester bonding COO− was observable. The XPS analyses confirmed the presence of N1s peak in Ph-CNF, meaning that the hydroxyl groups reacted with the amino groups (NH2) of phthalimide on the CNF surface. Based on the results, surface modification and addition of phthalimide increased the specific surface area, but also decreased the overall porosity, size of pores and volume of pores. When the temperature, humidity, pressure, and airflow rate increased, the CO2 adsorption significantly increased. The CO2 adsorption of phthalimide-modified CNF was confirmed by ATR-IR spectroscopy as the characteristic peaks of HCO−3,NH+3 and ester bonding NCOO− were visible on the spectra.

Place, publisher, year, edition, pages
Elsevier, 2020
Keywords
CO2 adsorption, Cellulose nanofiber, Aerogels, Chemical modification
National Category
Bio Materials
Research subject
Wood and Bionanocomposites
Identifiers
urn:nbn:se:ltu:diva-76954 (URN)10.1016/j.carbpol.2019.115571 (DOI)000504402300008 ()2-s2.0-85075451925 (Scopus ID)
Note

Validerad;2020;Nivå 2;2020-01-13 (johcin)

Available from: 2019-11-29 Created: 2019-11-29 Last updated: 2020-01-13Bibliographically approved
Wei, J., Geng, S., Hedlund, J. & Oksman, K. (2020). Lightweight, flexible, and multifunctional anisotropic nanocellulose-based aerogels for CO2 adsorption. Cellulose (London)
Open this publication in new window or tab >>Lightweight, flexible, and multifunctional anisotropic nanocellulose-based aerogels for CO2 adsorption
2020 (English)In: Cellulose (London), ISSN 0969-0239, E-ISSN 1572-882XArticle in journal (Refereed) Epub ahead of print
Abstract [en]

CO2 adsorption is a promising strategy to reduce costs and energy use for CO2 separation. In this study, we developed CO2 adsorbents based on lightweight and flexible cellulose nanofiber aerogels with monolithic structures prepared via freeze-casting, and cellulose acetate or acetylated cellulose nanocrystals (a-CNCs) were introduced into the aerogels as functional materials using an impregnation method to provide CO2 affinity. The microstructure of the adsorbent was examined using scanning electron microscopy, and compression tests were performed to analyze the mechanical properties of the adsorbents. The CO2 adsorption behavior was studied by recording the adsorption isotherms and performing column breakthrough experiments. The samples showed excellent mechanical performance and had a CO2 adsorption capacity of up to 1.14 mmol/g at 101 kPa and 273 K. Compared to the adsorbent which contains cellulose acetate, the one impregnated with a-CNCs had better CO2 adsorption capacity and axial mechanical properties owing to the building of a nanoscale scaffold on the surface of the adsorbent. Although the CO2 adsorption capacity could be improved further, this paper reports a potential CO2 adsorbent that uses all cellulose-based materials, which is beneficial for the environment from both resource and function perspectives. Moreover, the interesting impregnation process provides a new method to attach functional materials to aerogels, which have potential for use in many other applications.

Place, publisher, year, edition, pages
Springer, 2020
Keywords
Cellulose aerogel, CO2 adsorption, Freeze-casting, Cellulose nanocrystals, Acetylation
National Category
Materials Engineering Chemical Process Engineering Bio Materials
Research subject
Chemical Technology; Wood and Bionanocomposites
Identifiers
urn:nbn:se:ltu:diva-77515 (URN)10.1007/s10570-019-02935-7 (DOI)
Funder
Bio4Energy
Available from: 2020-01-24 Created: 2020-01-24 Last updated: 2020-01-27
Geng, S., Wei, J., Jonasson, S., Hedlund, J. & Oksman, K. (2020). Multifunctional Carbon Aerogels with Hierarchical Anisotropic Structure Derived from Lignin and Cellulose Nanofibers for CO2 Capture and Energy Storage. ACS Applied Materials and Interfaces
Open this publication in new window or tab >>Multifunctional Carbon Aerogels with Hierarchical Anisotropic Structure Derived from Lignin and Cellulose Nanofibers for CO2 Capture and Energy Storage
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2020 (English)In: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252Article in journal (Refereed) Epub ahead of print
Abstract [en]

In current times, CO2 capture and light-weight energy storage are receiving significant attention and will be vital functions in next-generation materials. Porous carbonaceous materials have great potential in these areas, whereas most of the developed carbon materials still have significant limitations, such as non-renewable resources, complex and costly processing or the absence of tailorable structure. In this study, a new strategy is developed for using the currently under-utilized lignin and cellulose nanofibers, which can be extracted from renewable resources to produce high-performance multifunctional carbon aerogels with a tailorable, anisotropic pore structure. Both the macro- and microstructure of the carbon aerogels can be simultaneously controlled by discreetly tuning the weight ratio of lignin to cellulose nanofibers in the carbon aerogel precursors, which considerably influences their final porosity and surface area. The designed carbon aerogels demonstrate excellent performance in both CO2 capture and capacitive energy storage, and the best results exhibit a CO2 adsorption capacity of 5.23 mmol g-1 at 273 K and 100 kPa, and a specific electrical double layer capacitance of 124 F g-1 at a current density of 0.2 A g-1, indicating that they have great future potential in the relevant applications.

Place, publisher, year, edition, pages
American Chemical Society (ACS), 2020
National Category
Materials Engineering Bio Materials Chemical Process Engineering
Research subject
Chemical Technology; Wood and Bionanocomposites
Identifiers
urn:nbn:se:ltu:diva-77516 (URN)10.1021/acsami.9b19955 (DOI)
Funder
Bio4EnergySwedish Research CouncilSwedish Research Council Formas
Available from: 2020-01-24 Created: 2020-01-24 Last updated: 2020-01-27
Nissilä, T., Oksman, K. & Hietala, M. (2019). A method for preparing epoxy-cellulose nanofiber composites with an oriented structure. Composites. Part A, Applied science and manufacturing, 125, Article ID 105515.
Open this publication in new window or tab >>A method for preparing epoxy-cellulose nanofiber composites with an oriented structure
2019 (English)In: Composites. Part A, Applied science and manufacturing, ISSN 1359-835X, E-ISSN 1878-5840, Vol. 125, article id 105515Article in journal (Refereed) Published
Abstract [en]

A method was developed for processing cellulose nanocomposites using conventional vacuum infusion. Porouscellulose nanofiber networks were prepared via ice-templating and used as preforms for impregnation with a bioepoxyresin. Microscopy studies showed a unidirectionally oriented micrometer-scale pore structure that facilitatedthe infusion process by providing flow channels for the resin. The permeability of the preforms wascomparable to that of natural fiber mats, and the infusion time significantly decreased after optimizing theprocessing temperature. The flexural modulus of the bio-epoxy increased from 2.5 to 4.4 GPa, the strengthincreased from 89 to 107 MPa, and the storage modulus increased from 2.8 to 4.2 GPa with 13 vol% cellulosenanofibers. The mechanical properties also showed anisotropy, as the flexural and storage moduli were approximately25% higher in the longitudinal direction, indicating that the nanofiber network inside the epoxymatrix had an oriented nature.

Place, publisher, year, edition, pages
Elsevier, 2019
Keywords
Cellulose, Nanocomposites, Mechanical properties, Vacuum infusion
National Category
Engineering and Technology Bio Materials
Research subject
Wood and Bionanocomposites
Identifiers
urn:nbn:se:ltu:diva-75412 (URN)10.1016/j.compositesa.2019.105515 (DOI)000484878200001 ()2-s2.0-85068541264 (Scopus ID)
Note

Validerad;2019;Nivå 2;2019-08-13 (johcin)

Available from: 2019-08-06 Created: 2019-08-06 Last updated: 2019-09-27Bibliographically approved
Wei, J., Geng, S., Pitkänen, O., Järvinen, T., Kordas, K. & Oksman, K. (2019). Biomass-derived electrospun carbon nanofiber networks for high-performance supercapacitors. In: : . Paper presented at The 22nd International Conference on Composite Materials (ICCM22).
Open this publication in new window or tab >>Biomass-derived electrospun carbon nanofiber networks for high-performance supercapacitors
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2019 (English)Conference paper, Oral presentation with published abstract (Refereed)
Keywords
Lignin, Carbon, Electrospinning, Supercapacitor, Nanofiber
National Category
Materials Engineering
Identifiers
urn:nbn:se:ltu:diva-76139 (URN)
Conference
The 22nd International Conference on Composite Materials (ICCM22)
Funder
Swedish Research Council, Carbon Lignin 2017-04240
Available from: 2019-09-27 Created: 2019-09-27 Last updated: 2019-10-22
Singh, S., Maspoch, M. L. & Oksman, K. (2019). Crystallization of triethyl-citrate-plasticized poly(lactic acid) induced by chitin nanocrystals. Journal of Applied Polymer Science, 136(36), Article ID 47936.
Open this publication in new window or tab >>Crystallization of triethyl-citrate-plasticized poly(lactic acid) induced by chitin nanocrystals
2019 (English)In: Journal of Applied Polymer Science, ISSN 0021-8995, E-ISSN 1097-4628, Vol. 136, no 36, article id 47936Article in journal (Refereed) Published
Abstract [en]

The aim of this study was to gain a better understanding of the crystallization behavior of triethyl-citrate-plasticizedpoly(lactic acid) (PLA–TEC) in the presence of chitin nanocrystals (ChNCs). The isothermal crystallization behavior of PLA–TEC wasstudied by polarized optical microscopy, scanning electron microscopy, differential scanning calorimetry, and X-ray diffraction (XRD).Interestingly, the addition of just 1 wt % ChNCs in PLA–TEC increased the crystallization rate in the temperature range of 135–125 C.The microscopy studies confirmed the presence of at least three distinct types of spherulites: negative, neutral, and ring banded. TheChNCs also increased the degree of crystallinity up to 32%, even at a fast cooling rate of 25 C min−1. The XRD studies further revealedthe nucleation effect induced by the addition of ChNCs and thus explained the faster crystallization rate. To conclude, the addition of asmall amount (1 wt %) of ChNC to plasticized PLA significantly affected its nucleation, crystal size, and crystallization speed; therefore,the proposed route can be considered suitable for improving the crystallization behavior of PLA. 

Place, publisher, year, edition, pages
John Wiley & Sons, 2019
Keywords
chitin nanocrystals, isothermal crystallization, microstructure, plasticizer, poly(lactic acid)
National Category
Bio Materials
Research subject
Wood and Bionanocomposites
Identifiers
urn:nbn:se:ltu:diva-73964 (URN)10.1002/APP.47936 (DOI)000471755000019 ()2-s2.0-85065669156 (Scopus ID)
Note

Validerad;2019;Nivå 2;2019-06-25 (johcin)

Available from: 2019-05-15 Created: 2019-05-15 Last updated: 2019-07-10Bibliographically approved
PATEL, M., Schwendemann, D., Geng, S. & Oksman, K. (2019). Dispersion of chitin nanocrystals in polylactic acid nanocomposites prepared via liquid assisted extrusion by triethyl citrate. In: : . Paper presented at 6th EPNOE International Polysaccharide Conference.
Open this publication in new window or tab >>Dispersion of chitin nanocrystals in polylactic acid nanocomposites prepared via liquid assisted extrusion by triethyl citrate
2019 (English)Conference paper, Poster (with or without abstract) (Other academic)
National Category
Other Materials Engineering Composite Science and Engineering
Identifiers
urn:nbn:se:ltu:diva-76971 (URN)
Conference
6th EPNOE International Polysaccharide Conference
Available from: 2019-11-29 Created: 2019-11-29 Last updated: 2019-11-29
Hassan, M., Zeid, R. E. A., Abou-Elseoud, W. S., Hassan, E., Berglund, L. & Oksman, K. (2019). Effect of Unbleached Rice Straw Cellulose Nanofibers on the Properties of Polysulfone Membranes. Polymers, 11(6), Article ID 938.
Open this publication in new window or tab >>Effect of Unbleached Rice Straw Cellulose Nanofibers on the Properties of Polysulfone Membranes
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2019 (English)In: Polymers, ISSN 2073-4360, E-ISSN 2073-4360, Vol. 11, no 6, article id 938Article in journal (Refereed) Published
Abstract [en]

In addition to their lower cost and more environmentally friendly nature, cellulose nanofibers isolated from unbleached pulps offer different surface properties and functionality than those isolated from bleached pulps. At the same time, nanofibers isolated from unbleached pulps keep interesting properties such as hydrophilicity and mechanical strength, close to those isolated from bleached pulps. In the current work, rice straw nanofibers (RSNF) isolated from unbleached neutral sulfite pulp (lignin content 14%) were used with polysulfone (PSF) polymer to make membrane via phase inversion. The effect of RSNF on microstructure, porosity, hydrophilicity, mechanical properties, water flux, and fouling of PSF membranes was studied. In addition, the prepared membranes were tested to remove lime nanoparticles, an example of medium-size nanoparticles. The results showed that using RSNF at loadings from 0.5 to 2 wt.% can significantly increase hydrophilicity, porosity, water flux, and antifouling properties of PSF. RSNF also brought about an increase in rejection of lime nanoparticles (up to 98% rejection) from their aqueous suspension, and at the same time, with increasing flux across the membranes. Tensile strength of the membranes improved by ~29% with addition of RSNF and the maximum improvement was obtained on using 0.5% of RSNF, while Young’s modulus improved by ~40% at the same RSNF loading. As compared to previous published results on using cellulose nanofibers isolated from bleached pulps, the obtained results in the current work showed potential application of nanofibers isolated from unbleached pulps for improving important properties of PSF membranes, such as hydrophilicity, water flux, rejection, and antifouling properties

Place, publisher, year, edition, pages
MDPI, 2019
Keywords
rice straw, cellulose nanofibers, unbleached pulp, polysulfone, membrane
National Category
Bio Materials
Research subject
Wood and Bionanocomposites
Identifiers
urn:nbn:se:ltu:diva-75163 (URN)10.3390/polym11060938 (DOI)000473819100010 ()31146496 (PubMedID)2-s2.0-85067339493 (Scopus ID)
Note

Validerad;2019;Nivå 2;2019-07-01 (johcin)

Available from: 2019-07-01 Created: 2019-07-01 Last updated: 2019-08-16Bibliographically approved
Singh, S., Rodriguez, C., Santana, O., Oksman, K. & Maspoch, M. (2019). Evaluation of mechanical properties of poly(lactic acid)/cellulose nanocrystal nanocomposites: A comparative study of conventional tensile test and small punch test. In: : . Paper presented at 36th Conference of the Spanish Group of Fracture, (GEF) 2019,Sivilla, Spain, 3-5 April, 2019.
Open this publication in new window or tab >>Evaluation of mechanical properties of poly(lactic acid)/cellulose nanocrystal nanocomposites: A comparative study of conventional tensile test and small punch test
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2019 (English)Conference paper, Oral presentation with published abstract (Refereed) [Artistic work]
National Category
Engineering and Technology
Identifiers
urn:nbn:se:ltu:diva-73395 (URN)
Conference
36th Conference of the Spanish Group of Fracture, (GEF) 2019,Sivilla, Spain, 3-5 April, 2019
Available from: 2019-04-02 Created: 2019-04-02 Last updated: 2019-04-02
Ghafari, R., Jonoobi, M., Mohammadi Amirabad, L., Oksman, K. & Taheri, A. R. (2019). Fabrication and characterization of novel bilayer scaffold from nanocellulose based aerogel for skin tissue engineering applications. International Journal of Biological Macromolecules, 136, 796-803
Open this publication in new window or tab >>Fabrication and characterization of novel bilayer scaffold from nanocellulose based aerogel for skin tissue engineering applications
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2019 (English)In: International Journal of Biological Macromolecules, ISSN 0141-8130, E-ISSN 1879-0003, Vol. 136, p. 796-803Article in journal (Refereed) Published
Abstract [en]

The aim of this study was to fabricate a novel bilayer scaffold containing cellulose nanofiber/poly (vinyl) alcohol (CNF/PVA) to evaluate its potential use in skin tissue engineering. Here, the scaffolds were fabricated using a novel one-step freeze-drying technique with two different concentrations of the aforementioned polymers. FE-SEM analysis indicated that the fabricated scaffolds had interconnected pores with two defined pore size in each layer of the bilayer scaffolds that can recapitulate the two layers of the dermis and epidermis of the skin. Lower concentration of polymers causes higher porosity with larger pore size and increased water uptake and decreased mechanical strength. FTIR proved the presence of functional groups and strong hydrogen bonding between the molecules of CNF/PVA and the efficient crosslinking. The MTT assay showed that these nanofibrous scaffolds meet the requirement as a biocompatible material for skin repair. Here, for the first time, we fabricated bilayer scaffold using a novel one-step freeze-drying technique only by controlling the polymer concentration with spending less time and energy.

Place, publisher, year, edition, pages
Elsevier, 2019
Keywords
Bilayered scaffold, Cellulose nanofiber (CNF), Freeze-drying, Skin tissue engineering
National Category
Bio Materials
Research subject
Wood and Bionanocomposites
Identifiers
urn:nbn:se:ltu:diva-75120 (URN)10.1016/j.ijbiomac.2019.06.104 (DOI)000482533000080 ()31226370 (PubMedID)2-s2.0-85067698284 (Scopus ID)
Note

Validerad;2019;Nivå 2;2019-06-28 (svasva)

Available from: 2019-06-28 Created: 2019-06-28 Last updated: 2019-09-13Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0003-4762-2854

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