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1. Submicron hierarchy of cellulose nanofibril films with etherified hemicelluloses

Author:
Tammelin, Tekla,   et al.   ; Nypelö, Tiina; Laine, Christiane; Colson, Jérôme; Henniges, Ute;     Show all 5 Authors
Source:
Carbohydrate polymers 2017 v.177 pp. 126-134
ISSN:
0144-8617
Subject:
additives; adhesion; atomic force microscopy; cellulose; cellulose microfibrils; hemicellulose; monitoring; nanofibers; oxygen; plasticizers; quartz; sorbitol; water solubility
Abstract:
... The lack of simple differentiation of all-polysaccharide-film components in nanoscale hinders unveiling their structure-property dependency. Submicron hierarchy of films of cellulose nanofibrils (CNFs) and carbohydrate-based additives was revealed via visualization of the components by their differentiating adhesion to an Atomic Force Microscope (AFM) tip. The differentiation of the film component ...
DOI:
10.1016/j.carbpol.2017.08.086

2. Interfacial Mechanisms of Water Vapor Sorption into Cellulose Nanofibril Films as Revealed by Quantitative Models

Author:
Tammelin, Tekla,   et al.   ; Hakalahti, Minna; Faustini, Marco; Boissière, Cédric; Kontturi, Eero;     Show all 5 Authors
Source:
Biomacromolecules 2017 v.18 no.9 pp. 2951-2958
ISSN:
1526-4602
Subject:
biocompatible materials; cellulose; models; monitoring; nanofibers; quartz; relative humidity; sorption; spectroscopy; water uptake; water vapor
Abstract:
... Humidity is an efficient instrument for facilitating changes in local architectures of two-dimensional surfaces assembled from nanoscaled biomaterials. Here, complementary surface-sensitive methods are used to collect explicit and precise experimental evidence on the water vapor sorption into (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO) oxidized cellulose nanofibril (CNF) thin film over the rel ...
DOI:
10.1021/acs.biomac.7b00890

3. Phase behaviour and droplet size of oil-in-water Pickering emulsions stabilised with plant-derived nanocellulosic materials A Physicochemical and engineering aspects

Author:
Tammelin, Tekla,   et al.   ; Gestranius, Marie; Stenius, Per; Kontturi, Eero; Sjöblom, Johan;     Show all 5 Authors
Source:
Colloids and surfaces 2017 v.519 pp. 60-70
ISSN:
0927-7757
Subject:
additives; cellulose; cellulose microfibrils; droplet size; droplets; emulsions; flocculation; nanocrystals; nanofibers; nuclear magnetic resonance spectroscopy; oils; storage time; temperature
Abstract:
... The preparation, stability and phase behaviour of oil-in-water emulsions formed by dodecane and water and stabilised by naturally amphiphilic, chemically unmodified cellulose nanofibrils (CNF), TEMPO-oxidized cellulose nanofibrils (T-CNF) and cellulose nanocrystals (CNC) were investigated. The stability towards prolonged storage, high temperature (maximum 85°C), shear and dilution with water was e ...
DOI:
10.1016/j.colsurfa.2016.04.025

4. In situ TEMPO surface functionalization of nanocellulose membranes for enhanced adsorption of metal ions from aqueous medium

Author:
Tammelin, Tekla,   et al.   ; Karim, Zoheb; Hakalahti, Minna; Mathew, Aji P.;     Show all 4 Authors
Source:
RSC advances 2017 v.7 no.9 pp. 5232-5241
ISSN:
2046-2069
Subject:
Fourier transform infrared spectroscopy; adsorption; atomic force microscopy; biodegradation; cellulose; cellulose nanofibers; coatings; contact angle; copper; gelatin; hydrophilicity; iron; metal ions; models; moieties; nanocrystals; oxidation; permeability; porosity; roughness; scanning electron microscopy; sludge; soil; titration; wastewater
Abstract:
... The current work demonstrates an innovative approach to develop nanocellulose based membranes with high water permeability, mechanical stability and high functionality via (1) tailoring the composition of the support layer of sludge microfibers/cellulose nanofibers (CNFSL) and (2) in situ TEMPO functionalization of the thin functional layer of cellulose nanocrystals (CNCBE) to enhance the metal io ...
DOI:
10.1039/c6ra25707k

5. Structural distinction due to deposition method in ultrathin films of cellulose nanofibres

Author:
Tammelin, Tekla,   et al.   ; Wilson, BenjaminP.; Yliniemi, Kirsi; Gestranius, Marie; Hakalahti, Minna; Putkonen, Matti; Lundström, Mari; Karppinen, Maarit; Kontturi, Eero;     Show all 9 Authors
Source:
Cellulose 2018 v.25 no.3 pp. 1715-1724
ISSN:
0969-0239
Subject:
Betula; adsorption; atomic force microscopy; cellulose; coatings; electrophoresis; monitoring; nanofibers; oxidation; pulp; quartz crystal microbalance; roughness; water vapor
Abstract:
... This research explores fundamental, structural differences of ultrathin films, prepared with three distinct deposition methods using 2,2,6,6-tetramethyl-piperidin-1-oxyl radical oxidized cellulose nanofibres (TEMPO-CNFs) derived from never dried bleached birch pulp. There is standard characterization by atomic force microscopy (morphology, roughness) and ellipsometry (thickness) and important stru ...
DOI:
10.1007/s10570-018-1665-y

6. Etherification of Wood-Based Hemicelluloses for Interfacial Activity

Author:
Tammelin, Tekla,   et al.   ; Nypelö, Tiina; Laine, Christiane; Aoki, Masaaki; Henniges, Ute;     Show all 5 Authors
Source:
Biomacromolecules 2016 v.17 no.5 pp. 1894-1901
ISSN:
1526-4602
Subject:
contact angle; emulsifying; ethers; gel chromatography; hardwood; hygroscopicity; mannans; nuclear magnetic resonance spectroscopy; oils; principal component analysis; reflectance; softwood; surface tension
Abstract:
... We present wetting, hygroscopicity, and interfacial activity of hemicellulose with respect to etherification and contrast it to their potential as interfacial modifiers, which is demonstrated by oil-in-water emulsification containing up to 60 vol% of the oil phase. Tunable amphiphilicity of hardwood and softwood hemicelluloses, xylans, and galactoglucomannans, respectively, was accomplished via co ...
DOI:
10.1021/acs.biomac.6b00355

7. Mimicking the Humidity Response of the Plant Cell Wall by Using Two-Dimensional Systems: The Critical Role of Amorphous and Crystalline Polysaccharides

Author:
Tammelin, Tekla,   et al.   ; Niinivaara, Elina; Faustini, Marco; Kontturi, Eero;     Show all 4 Authors
Source:
Langmuir 2016 v.32 no.8 pp. 2032-2040
ISSN:
1520-5827
Subject:
biomimetics; cell walls; cellulose; cellulose microfibrils; composite materials; hemicellulose; humidity; lignin; nanocrystals; quantitative analysis; spectroscopy; water vapor
Abstract:
... Of the composite materials occurring in nature, the plant cell wall is among the most intricate, consisting of a complex arrangement of semicrystalline cellulose microfibrils in a dissipative matrix of lignin and hemicelluloses. Here, a biomimetic, two-dimensional cellulose system of the cell wall structure is introduced where cellulose nanocrystals compose the crystalline portion and regenerated ...
DOI:
10.1021/acs.langmuir.5b04264

8. Understanding the interactions of cellulose fibres and deep eutectic solvent of choline chloride and urea

Author:
Tammelin, Tekla,   et al.   ; Tenhunen, Tiia-Maria; Lewandowska, Anna E.; Orelma, Hannes; Johansson, Leena-Sisko; Virtanen, Tommi; Harlin, Ali; Österberg, Monika; Eichhorn, Stephen J.;     Show all 9 Authors
Source:
Cellulose 2018 v.25 no.1 pp. 137-150
ISSN:
0969-0239
Subject:
Raman spectroscopy; X-ray photoelectron spectroscopy; adsorption; atomic force microscopy; carbohydrate content; cellulose; cellulosic fibers; chlorides; choline; derivatization; electrostatic interactions; ethanol; methylene blue; nitrogen; nitrogen content; nuclear magnetic resonance spectroscopy; pulp; scanning electron microscopy; solvents; spectral analysis; spinning; urea; washing
Abstract:
... A deep eutectic solvent composed of choline chloride (ChCl) and urea has been recently introduced as a promising cellulose compatible medium that enables e.g. fibre spinning. This paper clarifies the influence of such a solvent system on the structure and chemical composition of the cellulosic pulp fibres. Special emphasis was placed on the probable alterations of the chemical composition due to t ...
DOI:
10.1007/s10570-017-1587-0

9. Water Vapor Uptake of Ultrathin Films of Biologically Derived Nanocrystals: Quantitative Assessment with Quartz Crystal Microbalance and Spectroscopic Ellipsometry

Author:
Tammelin, Tekla,   et al.   ; Niinivaara, Elina; Faustini, Marco; Kontturi, Eero;     Show all 4 Authors
Source:
Langmuir 2015 v.31 no.44 pp. 12170-12176
ISSN:
1520-5827
Subject:
adsorption; cellulose; nanocrystals; quantitative analysis; quartz crystal microbalance; relative humidity; spectroscopy; water vapor
Abstract:
... Despite the relevance of water interactions, explicit analysis of vapor adsorption on biologically derived surfaces is often difficult. Here, a system was introduced to study the vapor uptake on a native polysaccharide surface; namely, cellulose nanocrystal (CNC) ultrathin films were examined with a quartz crystal microbalance with dissipation monitoring (QCM-D) and spectroscopic ellipsometry (SE) ...
DOI:
10.1021/acs.langmuir.5b01763

10. Effect of interfibrillar PVA bridging on water stability and mechanical properties of TEMPO/NaClO2 oxidized cellulosic nanofibril films

Author:
Tammelin, Tekla,   et al.   ; Hakalahti, Minna; Salminen, Arto; Seppälä, Jukka; Hänninen, Tuomas;     Show all 5 Authors
Source:
Carbohydrate polymers 2015 v.126 pp. 78-82
ISSN:
0144-8617
Subject:
alcohols; composite materials; films (materials); humidity; nanofibers; polyvinyl alcohol; soaking; tensile strength
Abstract:
... TEMPO/NaClO2 oxidized cellulosic nanofibrils (TCNF) were covalently bonded with poly(vinyl alcohol) (PVA) to render water stable films. Pure TCNF films and TCNF–PVA films in dry state showed similar humidity dependent behavior in the elastic region. However, in wet films PVA had a significant effect on stability and mechanical characteristics of the films. When soaked in water, pure TCNF films exh ...
DOI:
10.1016/j.carbpol.2015.03.007

11. Understanding the mechanisms of oxygen diffusion through surface functionalized nanocellulose films

Author:
Tammelin, Tekla,   et al.   ; Peresin, Maria Soledad; Kammiovirta, Kari; Heikkinen, Harri; Johansson, Leena-Sisko; Vartiainen, Jari; Setälä, Harri; Österberg, Monika;     Show all 8 Authors
Source:
Carbohydrate polymers 2017 v.174 pp. 309-317
ISSN:
0144-8617
Subject:
cellulose; cellulose microfibrils; hydrophilicity; nanofibers; oxygen; permeability; relative humidity; solvents
Abstract:
... A concept for direct surface modification on self-standing films of cellulose nanofibrils (CNF) is demonstrated using an aminosilane group in cellulose compatible solvent (dimethyl acetamide, DMA). The chemically modified structure efficiently prevents the oxygen molecules from interacting with the nanocellulose film in the presence of water molecules. Oxygen permeability values lower than 1mLmmm− ...
DOI:
10.1016/j.carbpol.2017.06.066

12. Strongly reduced thermal conductivity in hybrid ZnO/nanocellulose thin films

Author:
Tammelin, Tekla,   et al.   ; Jin, Hua; Marin, Giovanni; Giri, Ashutosh; Tynell, Tommi; Gestranius, Marie; Wilson, BenjaminP.; Kontturi, Eero; Hopkins, PatrickE.; Karppinen, Maarit;     Show all 10 Authors
Source:
Journal of materials science 2017 v.52 no.10 pp. 6093-6099
ISSN:
0022-2461
Subject:
cellulose; nanofibers; thermal conductivity; zinc oxide
Abstract:
... Utilizing a combination of atomic layer deposition and dip-coating techniques, we have incorporated natural nanocellulose fibers into an inorganic matrix in order to create a layered hybrid inorganic–organic thin-film structure. Such layer-engineered hybrid materials with an unorthodox combination of components are highly potential candidates for exciting new properties. Here, we show a more than ...
DOI:
10.1007/s10853-017-0848-5

13. Viscoelastic Properties of Core–Shell-Structured, Hemicellulose-Rich Nanofibrillated Cellulose in Dispersion and Wet-Film States

Author:
Tammelin, Tekla,   et al.   ; Tanaka, Reina; Saito, Tsuguyuki; Hänninen, Tuomas; Ono, Yuko; Hakalahti, Minna; Isogai, Akira;     Show all 7 Authors
Source:
Biomacromolecules 2016 v.17 no.6 pp. 2104-2111
ISSN:
1526-4602
Subject:
cellulose; crystallites; dispersions; hemicellulose; pH; salt concentration; storage modulus; sugars; viscoelasticity
Abstract:
... We report the viscoelastic properties of core–shell-structured, hemicellulose-rich nanofibrillated cellulose (NFC) in dispersion and wet-film states. The hemicellulose-rich NFC (hemicellulose neutral sugars 23%, carboxylate 0.2 mmol g–¹), prepared from Japanese persimmons, had a core crystallite thickness of 2.3 nm and unit fibril thickness of 4.2 nm. A carboxylate-rich NFC (hemicellulose neutral ...
DOI:
10.1021/acs.biomac.6b00316

14. Modified nanofibrillated cellulose–polyvinyl alcohol films with improved mechanical performance

Author:
Tammelin, Tekla,   et al.   ; Virtanen, Sanna; Vartianen, Jari; Setälä, Harri; Vuoti, Sauli;     Show all 5 Authors
Source:
RSC advances 2014 v.4 no.22 pp. 11343-11350
ISSN:
2046-2069
Subject:
alcohols; cellulose; composite films; composite materials; crystal structure; hydrogen peroxide; light; mechanical properties; polyvinyl alcohol; transmittance
Abstract:
... In this study chemically surface-modified nanofibrillated cellulose (NFC) was used at low levels (0.5 to 3 wt%) as reinforcement in a polyvinyl alcohol (PVA) matrix. The modified NFC–PVA films prepared by a solution casting technique showed improved mechanical performance and good optical properties. NFC was allylated and further epoxidised with hydrogen peroxide. The addition of 1 wt% epoxy-NFC e ...
DOI:
10.1039/c3ra46287k

15. UV-ozone patterning of micro-nano fibrillated cellulose (MNFC) with alkylsilane self-assembled monolayers

Author:
Tammelin, Tekla,   et al.   ; Kämäräinen, Tero; Arcot, Lokanathan R.; Johansson, Leena-Sisko; Campbell, Joseph; Franssila, Sami; Laine, Janne; Rojas, Orlando J.;     Show all 8 Authors
Source:
Cellulose 2016 v.23 no.3 pp. 1847-1857
ISSN:
0969-0239
Subject:
X-ray photoelectron spectroscopy; adsorption; atomic force microscopy; bovine serum albumin; cellulose; chemical composition; contact angle; diagnostic techniques; energy; hydrophilicity; hydrophobicity; ozone; pH
Abstract:
... We report on a facile photolithography-based procedure for surface energy patterning of novel micro-nano fibrillated cellulose (MNFC) films and demonstrate spatial control of protein adsorption. The kinetics of oxidative degradation of chemisorbed hydrophobic alkylsilane monolayers on MNFC upon exposure to UV/ozone and the effect on the adsorption of bovine serum albumin (BSA) as a function of pH ...
DOI:
10.1007/s10570-016-0942-x

16. Direct Interfacial Modification of Nanocellulose Films for Thermoresponsive Membrane Templates

Author:
Tammelin, Tekla,   et al.   ; Hakalahti, Minna; Mautner, Andreas; Johansson, Leena-Sisko; Hänninen, Tuomas; Setälä, Harri; Kontturi, Eero; Bismarck, Alexander;     Show all 8 Authors
Source:
ACS Applied Materials & Interfaces 2016 v.8 no.5 pp. 2923-2927
ISSN:
1944-8252
Subject:
cellulose; cellulose microfibrils; polymers; temperature
Abstract:
... This letter proposes a strategy to construct tunable films combining the physical characteristics of cellulose nanofibrils and smart polymers for membrane applications. A functional membrane template was obtained by first fabricating a water stable film from cellulose nanofibrils and subsequently surface grafting it with a thermoresponsive polymer, poly(N-isopropylacrylamide). The behavior of the ...
DOI:
10.1021/acsami.5b12300

17. Effects of charge ratios of xylan-poly(allylamine hydrochloride) complexes on their adsorption onto different surfaces

Author:
Tammelin, Tekla,   et al.   ; Galván, María Verónica; Peresin, María Soledad; Mocchiutti, Paulina; Granqvist, Niko; Zanuttini, Miguel Ángel;     Show all 6 Authors
Source:
Cellulose 2015 v.22 no.5 pp. 2955-2970
ISSN:
0969-0239
Subject:
adsorption; atomic force microscopy; cellulose; cellulosic fibers; electrolytes; ionic strength; monitoring; pH; particle size; polycyclic aromatic hydrocarbons; pulp; quartz; silica; sodium chloride; softwood; surface plasmon resonance; zeta potential
Abstract:
... The adsorption behavior of polyelectrolyte complexes (PECs) of poly(allylamine hydrochloride) (PAH) and 4-O-methylglucuronoxylan (Xyl) onto silica surface, cellulose nanofibrils (CNFs) model surfaces, and unbleached softwood kraft fibers was studied. Different charge ratios and ionic strengths of the liquid medium (q ⁻ /q ⁺: 0.3, 0.5 and 0.8 in 1 mM NaCl, and q ⁻ /q ⁺: 0.2, 0.3 and 0.5 in 10 mM Na ...
DOI:
10.1007/s10570-015-0706-z

18. Clean and reactive nanostructured cellulose surface

Author:
Tammelin, Tekla,   et al.   ; Österberg, Monika; Peresin, Maria Soledad; Johansson, Leena-Sisko;     Show all 4 Authors
Source:
Cellulose 2013 v.20 no.3 pp. 983-990
ISSN:
0969-0239
Subject:
X-ray photoelectron spectroscopy; carbon; cellulose; chemical degradation; contact angle; ozone; ultraviolet radiation
Abstract:
... A simple, solvent-free and low cost method to activate the surface of nanofibrillated cellulose films for further functionalization is presented. The method is based on the oxidative properties of UV radiation and ozone, to effectively remove contaminants from nanocellulosic surface, which remains clean and reactive for at least a week. The efficiency of the method is demonstrated by X-ray photoel ...
DOI:
10.1007/s10570-013-9920-8

19. Structural Features and Water Interactions of Etherified Xylan Thin Films

Author:
Tammelin, Tekla,   et al.   ; Peresin, Maria Soledad; Kammiovirta, Kari; Setälä, Harri;     Show all 4 Authors
Source:
Journal of polymers and the environment 2012 v.20 no.4 pp. 895-904
ISSN:
1566-2543
Subject:
Betula; atomic force microscopy; contact angle; crosslinking; heat treatment; hydrophilicity; hydrophobicity; quartz; relative humidity; viscoelasticity; water uptake; water vapor; xylan
Abstract:
... In this paper, the model film approach was used to investigate the structural features and humidity induced changes of the etherified xylan derivatives by using surface sensitive methods. Two routes to modify the birch xylan to generate either cross-linking xylan or more hydrophobic xylan were mastered via allylation and butylation, respectively. Thin nanometer scale model films were prepared by s ...
DOI:
10.1007/s10924-012-0469-7

20. Solvent impact on esterification and film formation ability of nanofibrillated cellulose

Author:
Tammelin, Tekla,   et al.   ; Vuoti, Sauli; Talja, Riku; Johansson, Leena-Sisko; Heikkinen, Harri;     Show all 5 Authors
Source:
Cellulose 2013 v.20 no.5 pp. 2359-2370
ISSN:
0969-0239
Subject:
X-ray photoelectron spectroscopy; acetates; acetone; carbon; cellulose; contact angle; dispersions; esterification; hydrophobicity; nuclear magnetic resonance spectroscopy; oxygen; surface area; water vapor
Abstract:
... In this study we have manufactured nanofibrillar cellulose and modified the fibre surface with ester groups in order to hydrophobise the surface. Nanofibrillated cellulose was chosen to demonstrate the phenomena, since due to its high surface area the effects at issue are pronounced. The prepared NFC ester derivatives were butyrate, hexanoate, benzoate, naphtoate, diphenyl acetate, stearate and pa ...
DOI:
10.1007/s10570-013-9983-6