Model Films from Native Cellulose Nanofibrils. Preparation, Swelling, and Surface Interactions

2008 ◽  
Vol 9 (4) ◽  
pp. 1273-1282 ◽  
Author(s):  
S. Ahola ◽  
J. Salmi ◽  
L.-S. Johansson ◽  
J. Laine ◽  
M. Österberg
Keyword(s):  
Cellulose Nanofibrils ◽  
Surface Interactions ◽  
Native Cellulose

Self-aligned integration of native cellulose nanofibrils towards producing diverse bulk materials

Soft Matter ◽  
2011 ◽  
Vol 7 (19) ◽  
pp. 8804 ◽  
Author(s):  
Tsuguyuki Saito ◽  
Takehiko Uematsu ◽  
Satoshi Kimura ◽  
Toshiharu Enomae ◽  
Akira Isogai
Keyword(s):  
Cellulose Nanofibrils ◽  
Bulk Materials ◽  
Native Cellulose

Reinforcement of all-cellulose nanocomposite films using native cellulose nanofibrils

2014 ◽  
Vol 104 ◽  
pp. 143-150 ◽  
Author(s):  
Jiangqi Zhao ◽  
Xu He ◽  
Yaru Wang ◽  
Wei Zhang ◽  
Xinxing Zhang ◽  
...  
Keyword(s):  
Cellulose Nanofibrils ◽  
Nanocomposite Films ◽  
Native Cellulose

Enzymatic Hydrolysis of Native Cellulose Nanofibrils and Other Cellulose Model Films: Effect of Surface Structure

Langmuir ◽  
2008 ◽  
Vol 24 (20) ◽  
pp. 11592-11599 ◽  
Author(s):  
S. Ahola ◽  
X. Turon ◽  
M. Österberg ◽  
J. Laine ◽  
O. J. Rojas
Keyword(s):  
Enzymatic Hydrolysis ◽  
Surface Structure ◽  
Cellulose Nanofibrils ◽  
Native Cellulose ◽  
Hydrolysis Of ◽  
Effect Of Surface

Colloidal Ionic Assembly between Anionic Native Cellulose Nanofibrils and Cationic Block Copolymer Micelles into Biomimetic Nanocomposites

2011 ◽  
Vol 12 (6) ◽  
pp. 2074-2081 ◽  
Author(s):  
Miao Wang ◽  
Anna Olszewska ◽  
Andreas Walther ◽  
Jani-Markus Malho ◽  
Felix H. Schacher ◽  
...  
Keyword(s):  
Block Copolymer ◽  
Cellulose Nanofibrils ◽  
Native Cellulose ◽  
Block Copolymer Micelles ◽  
Copolymer Micelles

Multifunctional High-Performance Biofibers Based on Wet-Extrusion of Renewable Native Cellulose Nanofibrils

2011 ◽  
Vol 23 (26) ◽  
pp. 2924-2928 ◽  
Author(s):  
Andreas Walther ◽  
Jaakko V. I. Timonen ◽  
Isabel Díez ◽  
Antti Laukkanen ◽  
Olli Ikkala
Keyword(s):  
High Performance ◽  
Cellulose Nanofibrils ◽  
Native Cellulose ◽  
Wet Extrusion

Humidity and Multiscale Structure Govern Mechanical Properties and Deformation Modes in Films of Native Cellulose Nanofibrils

2013 ◽  
Vol 14 (12) ◽  
pp. 4497-4506 ◽  
Author(s):  
Alejandro J. Benítez ◽  
Jose Torres-Rendon ◽  
Mikko Poutanen ◽  
Andreas Walther
Keyword(s):  
Mechanical Properties ◽  
Cellulose Nanofibrils ◽  
Native Cellulose ◽  
Multiscale Structure ◽  
Deformation Modes

scholarly journals Enhancing the Stability of Aqueous Dispersions and Foams Comprising Cellulose Nanofibrils (CNF) with CaCO3 Particles

Nanomaterials ◽  
2018 ◽  
Vol 8 (9) ◽  
pp. 651 ◽  
Author(s):  
Tiia-Maria Tenhunen ◽  
Tiina Pöhler ◽  
Annaleena Kokko ◽  
Hannes Orelma ◽  
Patrick Gane ◽  
...  
Keyword(s):  
Cellulose Nanofibrils ◽  
Surface Interactions ◽  
Stability Assessment ◽  
Aqueous Dispersions ◽  
Inorganic Particles ◽  
Polyelectrolyte Layer ◽  
Overall Stability ◽  
The Stability ◽  
Surface Modified ◽  
Work Stability

In this work, stability of dispersions and foams containing CaCO3-based pigments and cellulose nanofibrils (CNF) was evaluated with the aim to reveal the mechanisms contributing to the overall stability of the selected systems. The utmost interest lies in the recently developed hydrocolloid hybrid CaCO3 pigments and their potential to form bionanocomposite structures when incorporated with CNF. These pigments possess a polyelectrolyte layer deposited on the surface of the particle which is expected to enhance the compatibility between inorganic and organic components. Stability assessment of both dispersions and foams was conducted using turbidity profile scanning. In dispersions, CNF provides stability due to its ability to form a firm percolation network. If surface-modified pigments are introduced, the favourable surface interactions between the pigments and CNF positively influence the stability behaviour and even large macro-size pigments do not interfere with the stability of either dispersions or foams. In foams, the stability can be enhanced due to the synergistic actions brought by CNF and particles with suitable size, shape and wetting characteristics resulting in a condition where the stability mechanism is defined by the formation of a continuous plateau border incorporating a CNF network which is able to trap the inorganic particles uniformly.

Study of Tip-Surface Interactions in Scanning Tunneling Microscopy (STM) by Reflection Electron Microscopy (REM)

1990 ◽  
Vol 48 (1) ◽  
pp. 320-321
Author(s):  
W. Lo ◽  
J.C.H. Spence ◽  
M. Kuwabara
Keyword(s):  
High Resolution ◽  
Elastic Strain ◽  
Tunneling Current ◽  
Surface Damage ◽  
Surface Interactions ◽  
Graphite Surface ◽  
Scanning Tunneling ◽  
Large Area ◽  
Tunneling Microscopy ◽  
High Resolution Tem

Work on the integration of STM with REM has demonstrated the usefulness of this combination. The STM has been designed to replace the side entry holder of a commercial Philips 400T TEM. It allows simultaneous REM imaging of the tip/sample region of the STM (see fig. 1). The REM technique offers nigh sensitivity to strain (<10−4) through diffraction contrast and high resolution (<lnm) along the unforeshortened direction. It is an ideal technique to use for studying tip/surface interactions in STM.The elastic strain associated with tunnelling was first imaged on cleaved, highly doped (S doped, 5 × 1018cm-3) InP(110). The tip and surface damage observed provided strong evidence that the strain was caused by tip/surface contact, most likely through an insulating adsorbate layer. This is consistent with the picture that tunnelling in air, liquid or ordinary vacuum (such as in a TEM) occurs through a layer of contamination. The tip, under servo control, must compress the insulating contamination layer in order to get close enough to the sample to tunnel. The contaminant thereby transmits the stress to the sample. Elastic strain while tunnelling from graphite has been detected by others, but never directly imaged before. Recent results using the STM/REM combination has yielded the first direct evidence of strain while tunnelling from graphite. Figure 2 shows a graphite surface elastically strained by the STM tip while tunnelling (It=3nA, Vtip=−20mV). Video images of other graphite surfaces show a reversible strain feature following the tip as it is scanned. The elastic strain field is sometimes seen to extend hundreds of nanometers from the tip. Also commonly observed while tunnelling from graphite is an increase in the RHEED intensity of the scanned region (see fig.3). Debris is seen on the tip and along the left edges of the brightened scan region of figure 4, suggesting that tip abrasion of the surface has occurred. High resolution TEM images of other tips show what appear to be attached graphite flakes. The removal of contamination, possibly along with the top few layers of graphite, seems a likely explanation for the observed increase in RHEED reflectivity. These results are not inconsistent with the “sliding planes” model of tunnelling on graphite“. Here, it was proposed that the force due to the tunnelling probe acts over a large area, causing shear of the graphite planes when the tip is scanned. The tunneling current is then modulated as the planes of graphite slide in and out of registry. The possiblity of true vacuum tunnelling from the cleaned graphite surface has not been ruled out. STM work function measurements are needed to test this.

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