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Vegunta, V. L., Deshpande, R., Lindén, P., Sevastyanova, O., Garcia, A., Björk, M., . . . Lindström, M. (2023). Addition of Green and Black Liquor in Kraft Pulping of Eucalyptus dunnii wood: Possible Solutions for the Problems with Kraft Pulping Caused by High Calcium Content..
Open this publication in new window or tab >>Addition of Green and Black Liquor in Kraft Pulping of Eucalyptus dunnii wood: Possible Solutions for the Problems with Kraft Pulping Caused by High Calcium Content.
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2023 (English)Manuscript (preprint) (Other academic)
Abstract [en]

Samples of Eucalyptus dunnii with high calcium content have less good pulping properties regarding delignification and polysaccharide degradation, as it was shown by us earlier. In this work, we tested the addition of black liquor and green liquor to the Eucalyptus dunnii chips before kraft pulping, Specific improvements were obtained with both liquors, but the most substantial effect was observed with the green liquor, where even wood with the highest calcium content was pulped with a good result. Delignification was faster, and viscosity losses (degree of polymerization of cellulose) were higher for samples treated with green liquor prior to kraft pulping. Bleaching experiments showed that the bleachability of the green liquor-treated pulp was virtually the same as for a control pulp and that the higher viscosity of the bleached pulp was maintained. Possible chemical explanations for the results obtained are discussed.

National Category
Natural Sciences
Identifiers
urn:nbn:se:kth:diva-323319 (URN)
Note

I listan över avhandlingens delarbeten står detta arbete med titeln "Green and black liquor impregnation:possible solutions for problems with kraft pulping caused by calciumcontent.".

QC 20230919

Available from: 2023-01-25 Created: 2023-01-25 Last updated: 2023-09-19Bibliographically approved
Li, H., Kulachenko, A., Mathew, A. P., Stoltz, R. B. & Sevastyanova, O. (2023). Enhancing the Strength and Flexibility of Microfibrillated Cellulose Films from Lignin-Rich Kraft Pulp. ACS Sustainable Chemistry and Engineering, 11(47), 16793-16805
Open this publication in new window or tab >>Enhancing the Strength and Flexibility of Microfibrillated Cellulose Films from Lignin-Rich Kraft Pulp
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2023 (English)In: ACS Sustainable Chemistry and Engineering, E-ISSN 2168-0485, Vol. 11, no 47, p. 16793-16805Article in journal (Refereed) Published
Abstract [en]

Recent progress in nanocellulose production favors lignin-rich raw fibers due to their cost effectiveness, higher yield of unbleached pulp, and added benefits from residual lignin, positioning them as ideal substitutes for fossil-based materials in composites and packaging. Nonetheless, their application has been impeded due to their inferior mechanical properties. This study introduces a simplified method to enhance the strength of lignin-containing microfibrillated cellulose (LMFC) films using water as a plasticizer during drying. Both LMFC from unbleached pulps and lignin-free microfibrillated cellulose (MFC) from fully bleached industrial kraft pulp were prepared through an environmentally friendly and scalable method. Given the charged carboxylic groups from hemicellulose and residual lignin, the LMFC gel demonstrated greater colloidal stability compared to MFC. Moreover, lignin-rich films displayed heightened hydrophobicity and exceptional thermal stability (T-max > 345 degrees C). A significant improvement in tensile strength and Young's modulus of LMFC films was achieved with an elevated drying temperature from 40 degrees C to above 90 degrees C, increasing tensile strength from 248 to 283 MPa and Young's modulus by 84%. These improvements are attributed to the thermoplastic nature of lignin and the plasticizing effect of water at elevated temperatures. The longer fibers in microfibrillated films also improved the resistance to cracking in a folded state. The study highlights that enhancement of the properties of lignin-rich films can occur during the film making step itself, hinting at a sustainable, innovative method for creating robust and scalable materials for flexible devices, biocomposites, and packaging.

Place, publisher, year, edition, pages
American Chemical Society (ACS), 2023
Keywords
lignin-rich cellulose, microfibrillated cellulose, film, drying, flexibility, strengthenhancement
National Category
Paper, Pulp and Fiber Technology
Identifiers
urn:nbn:se:kth:diva-343058 (URN)10.1021/acssuschemeng.3c05086 (DOI)001141323500001 ()2-s2.0-85178151774 (Scopus ID)
Note

QC 20240206

Available from: 2024-02-06 Created: 2024-02-06 Last updated: 2024-02-06Bibliographically approved
Ribca, I., Sochor, B., Betker, M., Roth, S. V., Lawoko, M., Sevastyanova, O., . . . Johansson, M. (2023). Impact of lignin source on the performance of thermoset resins. European Polymer Journal, 194, 112141-112141, Article ID 112141.
Open this publication in new window or tab >>Impact of lignin source on the performance of thermoset resins
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2023 (English)In: European Polymer Journal, ISSN 0014-3057, E-ISSN 1873-1945, Vol. 194, p. 112141-112141, article id 112141Article in journal (Refereed) Published
Abstract [en]

A series of different technical hardwood lignin-based resins have been successfully synthesized, characterized, and utilised to produce thiol-ene thermoset polymers. Firstly, technical lignin was fractionated and allylated, whereafter it was crosslinked with a trifunctional thiol. Structural and morphological characteristics of the lignin fractions were studied by 1H NMR, 31P NMR, SEC, FTIR, DSC, TGA, and WAXS. The hardwood lignin fractions have a high content of C5-substituted OH groups. The WAXS studies on lignin fractions revealed the presence of two π-π stacking conformations, sandwiched (4.08–4.25 Å) and T-shaped (6.52–6.91 Å). The presence of lignin superstructures with distances/sizes between 10.5 and 12.8 Å was also identified. The curing reaction of the thermosets was investigated by RT-FTIR. Almost all thermosets (excepting one fraction) reached 95% of the thiol conversion in less than 17 h, revealing the enhanced reactivity of the allylated hardwood lignin samples.

The mechanical properties of the thermosets were investigated by DMA. The curing performance, as well as the final thermoset properties, have been correlated to variations in chemical composition and morphological differences of lignin fractions. The described results clearly demonstrate that technical hardwood lignins can be utilized for these applications, but also that significant differences compared to softwood lignins have to be considered for material design.

Place, publisher, year, edition, pages
Elsevier BV, 2023
Keywords
Hardwood lignin, Solvent fractionation, Allylation, Thiol-ene thermosets, Wide-angle X-ray scattering, π-π stacking interactions
National Category
Materials Chemistry Polymer Technologies Polymer Chemistry Paper, Pulp and Fiber Technology
Research subject
Chemistry
Identifiers
urn:nbn:se:kth:diva-327220 (URN)10.1016/j.eurpolymj.2023.112141 (DOI)001000190100001 ()2-s2.0-85159278832 (Scopus ID)
Funder
KTH Royal Institute of Technology
Note

QC 20230524

Available from: 2023-05-22 Created: 2023-05-22 Last updated: 2023-06-26Bibliographically approved
Mkrtchyan, S., Shkoor, M., Phanindrudu, M., Medved′, M., Sevastyanova, O. & Iaroshenko, V. O. (2023). Mechanochemical Defluorinative Arylation of Trifluoroacetamides: An Entry to Aromatic Amides. Journal of Organic Chemistry, 88(2), 863-870
Open this publication in new window or tab >>Mechanochemical Defluorinative Arylation of Trifluoroacetamides: An Entry to Aromatic Amides
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2023 (English)In: Journal of Organic Chemistry, ISSN 0022-3263, E-ISSN 1520-6904, Vol. 88, no 2, p. 863-870Article in journal (Refereed) Published
Abstract [en]

The amide bond is prominent in natural and synthetic organic molecules endowed with activity in various fields. Among a wide array of amide synthetic methods, substitution on a pre-existing (O)C-N moiety is an underexplored strategy for the synthesis of amides. In this work, we disclose a new protocol for the defluorinative arylation of aliphatic and aromatic trifluoroacetamides yielding aromatic amides. The mechanochemically induced reaction of either arylboronic acids, trimethoxyphenylsilanes, diaryliodonium salts, or dimethyl(phenyl)sulfonium salts with trifluoroacetamides affords substituted aromatic amides in good to excellent yields. These nickel-catalyzed reactions are enabled by C-CF3 bond activation using Dy2O3 as an additive. The current protocol provides versatile and scalable routes for accessing a wide variety of substituted aromatic amides. Moreover, the protocol described in this work overcomes the drawbacks and limitations in the previously reported methods.

Place, publisher, year, edition, pages
American Chemical Society (ACS), 2023
National Category
Organic Chemistry Polymer Chemistry Wood Science
Identifiers
urn:nbn:se:kth:diva-330080 (URN)10.1021/acs.joc.2c02197 (DOI)000914864300001 ()36622848 (PubMedID)2-s2.0-85146130268 (Scopus ID)
Note

QC 20231122

Available from: 2023-06-26 Created: 2023-06-26 Last updated: 2023-11-22Bibliographically approved
Pylypchuk, I. V., Karlsson, M., Lindén, P., Lindström, M., Elder, T., Sevastyanova, O. & Lawoko, M. (2023). Molecular understanding of the morphology and properties of lignin nanoparticles: unravelling the potential for tailored applications. Green Chemistry, 25(11), 4415-4428
Open this publication in new window or tab >>Molecular understanding of the morphology and properties of lignin nanoparticles: unravelling the potential for tailored applications
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2023 (English)In: Green Chemistry, ISSN 1463-9262, E-ISSN 1463-9270, Vol. 25, no 11, p. 4415-4428Article in journal (Refereed) Published
Abstract [en]

Studies have shown that the size of LNP depends on the molecular weight (M-w) of lignin. There is however need for deeper understanding on the role of molecular structure on LNP formation and its properties, in order to build a solid foundation on structure-property relationships. In this study, we show, for similar M-w lignins, that the size and morphology of LNPs depends on the molecular structure of the lignin macromolecule. More specifically, the molecular structure determined the molecular conformations, which in turn affects the inter-molecular assembly to yield size- and morphological-differences between LNPs. This was supported by density functional theory (DFT) modelling of representative structural motifs of three lignins sourced from Kraft and Organosolv processes. The obtained conformational differences are clearly explained by intra-molecular sandwich and/or T-shaped pi-pi stacking, the stacking type determined by the precise lignin structure. Moreover, the experimentally identified structures were detected in the superficial layer of LNPs in aqueous solution, confirming the theoretically predicted self-assembly patterns. The present work demonstrates that LNP properties can be molecularly tailored, consequently creating an avenue for tailored applications.

Place, publisher, year, edition, pages
Royal Society of Chemistry (RSC), 2023
National Category
Paper, Pulp and Fiber Technology
Identifiers
urn:nbn:se:kth:diva-329444 (URN)10.1039/d3gc00703k (DOI)000990236600001 ()37288453 (PubMedID)2-s2.0-85160412902 (Scopus ID)
Note

QC 20230621

Available from: 2023-06-21 Created: 2023-06-21 Last updated: 2023-06-21Bibliographically approved
Podkoscielna, B., Gargol, M., Goliszek, M., Klepka, T. & Sevastyanova, O. (2022). Degradation and flammability of bioplastics based on PLA and lignin. Polymer testing, 111, Article ID 107622.
Open this publication in new window or tab >>Degradation and flammability of bioplastics based on PLA and lignin
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2022 (English)In: Polymer testing, ISSN 0142-9418, E-ISSN 1873-2348, Vol. 111, article id 107622Article in journal (Refereed) Published
Abstract [en]

This article presents the preparation of polylactide (PLA)-derived bioplastics, where kraft lignin (L), sulfonated kraft lignin (L-SO3H) or sulfonated kraft lignin in combination with silica (L-SO3H+SiO2) were used as natural additives. The functional groups present in the obtained bioplastics was investigated using Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR) and their thermal properties were investigated using Differential Scanning Calorimetry (DSC) as well as Thermogravimetric analysis (TG). The impact of different additive combinations as well as the aging process on the properties of bioplastics, including their flammability characteristics, were investigated in detail. Additionally, mechanisms have been proposed to explain the observed network fragmentation during burning.

Place, publisher, year, edition, pages
Elsevier BV, 2022
National Category
Polymer Chemistry
Identifiers
urn:nbn:se:kth:diva-313759 (URN)10.1016/j.polymertesting.2022.107622 (DOI)000799991800004 ()2-s2.0-85129520920 (Scopus ID)
Note

QC 20220613

Available from: 2022-06-13 Created: 2022-06-13 Last updated: 2022-06-25Bibliographically approved
Vegunta, V. L., Senthilkumar, E. R., Lindén, P., Sevastyanova, O., Vilaplana, F., Garcia, A., . . . Lindström, M. E. (2022). High calcium content of Eucalyptus dunnii wood affects delignification and polysaccharide degradation in kraft pulping. Nordic Pulp & Paper Research Journal, 37(2), 338-348
Open this publication in new window or tab >>High calcium content of Eucalyptus dunnii wood affects delignification and polysaccharide degradation in kraft pulping
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2022 (English)In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 37, no 2, p. 338-348Article in journal (Refereed) Published
Abstract [en]

Eucalyptus dunnii is cultivated in Uruguay for kraft pulping purposes. However, depending on the growth site, the kraft pulping properties of the wood vary highly, and in some cases, pulping is difficult. Different batches of wood were chemically characterized and the only significant difference related to the pulping properties was the calcium content. The calcium appears to at least partly be present in the form of crystals in the lumen. Kraft pulping experiments on wood with different calcium contents indicated that high calcium led to slower delignification, and higher yield losses. Hexeneuronic acid formation was not significantly affected. Possible mechanistic explanations for these effects are discussed. 

Place, publisher, year, edition, pages
Walter de Gruyter GmbH, 2022
Keywords
calcium, delignification, eucalyptus, kraft pulping, polysaccharide degradation, Wood, Calcium content, Eucalypti, Eucalyptus dunnii, Growth sites, High calciums, Higher yield, Property, Pulping properties, Uruguay, Kraft pulp, Acids, Experimentation, Formation
National Category
Paper, Pulp and Fiber Technology
Identifiers
urn:nbn:se:kth:diva-323791 (URN)10.1515/npprj-2021-0069 (DOI)000789624800001 ()2-s2.0-85129838796 (Scopus ID)
Note

QC 20230213

Available from: 2023-02-13 Created: 2023-02-13 Last updated: 2023-02-13Bibliographically approved
Vegunta, V. L., Senthilkumar, E. R., Lindén, P., Sevastyanova, O., Vilaplana, F. & Lindström, M. (2022). High calcium content of Eucalyptus dunnii woodaffects delignification and polysaccharidedegradation in kraft pulping. Nordic Pulp & Paper Research Journal
Open this publication in new window or tab >>High calcium content of Eucalyptus dunnii woodaffects delignification and polysaccharidedegradation in kraft pulping
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2022 (English)In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669Article in journal (Other (popular science, discussion, etc.)) Published
Abstract [en]

Eucalyptus dunnii is cultivated in Uruguay for kraft pulping purposes. However, depending on the growth site, the kraft pulping properties of the wood vary highly, and in some cases, pulping is difficult. Different batches of wood were chemically characterized and the only significant difference related to the pulping properties was the calcium content. The calcium appears to at least partly be present in the form of crystals in the lumen. Kraft pulping experiments on wood with different calcium contents indicated that high calcium led to slower delignification, and higher yield losses. Hexeneuronic acid formation was not significantly affected. Possible mechanistic explanations for these effects are discussed.

National Category
Natural Sciences
Identifiers
urn:nbn:se:kth:diva-323321 (URN)
Note

QC 20230328

Available from: 2023-01-25 Created: 2023-01-25 Last updated: 2023-03-28Bibliographically approved
Pylypchuk, I. V., Suo, H., Chucheepchuenkamol, C., Jedicke, N., Lindén, P., Lindström, M., . . . Yevsa, T. (2022). High-Molecular-Weight Fractions of Spruce and Eucalyptus Lignin as a Perspective Nanoparticle-Based Platform for a Therapy Delivery in Liver Cancer. Frontiers in Bioengineering and Biotechnology, 9, Article ID 817768.
Open this publication in new window or tab >>High-Molecular-Weight Fractions of Spruce and Eucalyptus Lignin as a Perspective Nanoparticle-Based Platform for a Therapy Delivery in Liver Cancer
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2022 (English)In: Frontiers in Bioengineering and Biotechnology, E-ISSN 2296-4185, Vol. 9, article id 817768Article in journal (Refereed) Published
Abstract [en]

The natural polymer, lignin, possesses unique biodegradable and biocompatible properties, making it highly attractive for the generation of nanoparticles for targeted cancer therapy. In this study, we investigated spruce and eucalyptus lignin nanoparticles (designated as S-and E-LNPs, respectively). Both LNP types were generated from high-molecular-weight (M-w) kraft lignin obtained as insoluble residues after a five-step solvent fractionation approach, which included ethyl acetate, ethanol, methanol, and acetone. The resulting S-and E-LNPs ranged in size from 16 to 60 nm with uniform spherical shape regardless of the type of lignin. The preparation of LNPs from an acetone-insoluble lignin fraction is attractive because of the use of high-M-w lignin that is otherwise not suitable for most polymeric applications, its potential scalability, and the consistent size of the LNPs, which was independent of increased lignin concentrations. Due to the potential of LNPs to serve as delivery platforms in liver cancer treatment, we tested, for the first time, the efficacy of newly generated E-LNPs and S-LNPs in two types of primary liver cancer, hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA), in vitro. Both S-LNPs and E-LNPs inhibited the proliferation of HCC cells in a dose-dependent manner and did not affect CCA cell line growth. The inhibitory effect toward HCC was more pronounced in the E-LNP-treated group and was comparable to the standard therapy, sorafenib. Also, E-LNPs induced late apoptosis and necroptosis while inhibiting the HCC cell line. This study demonstrated that an elevated number of carbohydrates on the surface of the LNPs, as shown by NMR, seem to play an important role in mediating the interaction between LNPs and eukaryotic cells. The latter effect was most pronounced in E-LNPs. The novel S- and E-LNPs generated in this work are promising materials for biomedicine with advantageous properties such as small particle size and tailored surface functionality, making them an attractive and potentially biodegradable delivery tool for combination therapy in liver cancer, which still has to be verified in vivo using HCC and CCA models.

Place, publisher, year, edition, pages
Frontiers Media SA, 2022
Keywords
lignin nanoparticles (LNPs), cancer treatment, eucalyptus lignin, spruce lignin, primary liver cancer (PLC), hepatocellular carcinoma (HCC), cholangiocarcinoma (CCA), apoptosis
National Category
Paper, Pulp and Fiber Technology
Identifiers
urn:nbn:se:kth:diva-310043 (URN)10.3389/fbioe.2021.817768 (DOI)000760451300001 ()35198551 (PubMedID)2-s2.0-85125103461 (Scopus ID)
Note

QC 20220322

Available from: 2022-03-22 Created: 2022-03-22 Last updated: 2022-06-25Bibliographically approved
Gordobil, O., Li, H., Izquierdo, A. A., Egizabal, A., Sevastyanova, O. & Sandak, A. (2022). Surface chemistry and bioactivity of colloidal particles from industrial kraft lignins. International Journal of Biological Macromolecules, 220, 1444-1453
Open this publication in new window or tab >>Surface chemistry and bioactivity of colloidal particles from industrial kraft lignins
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2022 (English)In: International Journal of Biological Macromolecules, ISSN 0141-8130, E-ISSN 1879-0003, Vol. 220, p. 1444-1453Article in journal (Refereed) Published
Abstract [en]

The morphology control of lignin through particle size reduction to nanoscale seems to be a suitable conversion technology to overcome the intrinsic limitations of its native form to develop a wide range of biomaterials with high performance. Colloidal lignin particles (CLPs) in the range of 150-200 nm were synthesised from hardwood and softwood kraft lignins by the solvent shifting method. The initial molecular features of kraft lignins were evaluated in terms of purity, molecular weight distribution, and chemical functionalities. The impact of the lignin source and structure on the morphology, size distribution, and surface chemistry of CLPs was evaluated by particle size analyser, SEM, TEM and H-1 NMR. The results evidenced the influence of the botanical origin on the morphology and surface chemistry of particles. Furthermore, the antioxidant properties and cytotoxicity of lignins and corresponding CLPs, towards lung fibroblast cells were compared. CLPs from hardwood kraft lignins exhibited higher antioxidant power against DPPH free radical and a higher cytotoxic effect (IC30 = 67-70 mu g/mL) against lung fibroblast when compared to CLPs from softwood kraft lignin (IC30 = similar to 91 mu g/mL). However, the cytotoxicity of these biomaterials was dose-dependent, suggesting their potential application as active ingredients in cosmetic and pharmaceutic products at low concentrations.

Place, publisher, year, edition, pages
Elsevier BV, 2022
Keywords
Kraft lignin, Colloidal particles, Morphology, Surface chemistry, Antioxidant activity, Cytotoxicity
National Category
Paper, Pulp and Fiber Technology
Identifiers
urn:nbn:se:kth:diva-320307 (URN)10.1016/j.ijbiomac.2022.09.111 (DOI)000861503900003 ()36122772 (PubMedID)2-s2.0-85138209571 (Scopus ID)
Note

QC 20221024

Available from: 2022-10-24 Created: 2022-10-24 Last updated: 2022-10-24Bibliographically approved
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ORCID iD: ORCID iD iconorcid.org/0000-0001-7433-0350

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