scholarly journals Inducing nematic ordering of cellulose nanofibers using osmotic dehydration

Nanoscale ◽  
2018 ◽  
Vol 10 (48) ◽  
pp. 23157-23163 ◽  
Author(s):  
Valentina Guccini ◽  
Shun Yu ◽  
Michael Agthe ◽  
Korneliya Gordeyeva ◽  
Yulia Trushkina ◽  
...  
Keyword(s):  
Optical Microscopy ◽  
Small Angle ◽  
Order Parameter ◽  
Osmotic Dehydration ◽  
Cellulose Nanofibers ◽  
Polarized Optical Microscopy ◽  
X Ray ◽  
Rheological Measurements ◽  
Nematic Ordering ◽  
X Ray Scattering

The formation of nematically-ordered cellulose nanofiber (CNF) suspensions with an order parameter fmax ≈ 0.8 is studied by polarized optical microscopy, small-angle X-ray scattering (SAXS), and rheological measurements as a function of CNF concentration.

Supramolecular Structures Based on New Bolaamphiphile Molecules Investigated by Small Angle and Wide Angle X-ray Scattering and Polarized Optical Microscopy

2009 ◽  
Vol 113 (47) ◽  
pp. 15433-15444 ◽  
Author(s):  
Mathieu Berchel ◽  
Cristelle Mériadec ◽  
Loïc Lemiègre ◽  
Franck Artzner ◽  
Jelena Jeftić ◽  
...  
Keyword(s):  
Optical Microscopy ◽  
Small Angle ◽  
Supramolecular Structures ◽  
Wide Angle ◽  
Polarized Optical Microscopy ◽  
X Ray ◽  
X Ray Scattering ◽  
Ray Scattering

scholarly journals Inducing Nematic Ordering of Cellulose Nanofibers using Osmotic Dehydration

2018 ◽  
Author(s):  
Valentina Guccini ◽  
Shun Yu ◽  
Michael Agthe ◽  
Korneliya Gordeyeva ◽  
Yulia Trushkina ◽  
...  
Keyword(s):  
Osmotic Dehydration ◽  
Cellulose Nanofibers ◽  
Gel Formation ◽  
Fractal Structures ◽  
Maximum Order ◽  
X Ray ◽  
Nematic Ordering ◽  
X Ray Scattering ◽  
Wide Range

<div><div><p>The formation and characterization of nematically-ordered CNF materials (maximum order parameter f ≈ 0.8) has been studied by polarized optical microscopy, small angle x-ray scattering (SAXS), and rheological measurements as a function of CNF concentration. The wide range of CNF concentrations, from 0.5 wt% to 4.9 wt%, is obtained using osmotic dehydration with PEG. At concentrations >1.05 wt% the CNF suspension crosses an isotropic-anisotropic transition that is accompanied by a dramatic increase of the optical birefringence. The resulting nanostructures are depicted by a hierarchical model with mass fractal structures that converge into co-existing nematically-ordered regions and network-like regions, in which the correlation distances decrease upon increasing concentration. The use of rapid, upscaleble osmotic dehydration is an effective method to increase the concentration of CNF suspensions while partly circumventing the gel formation. The facile formation of highly ordered fibers can result in materials with interesting macroscopic properties.</p></div></div>

scholarly journals Inducing Nematic Ordering of Cellulose Nanofibers using Osmotic Dehydration

2018 ◽  
Author(s):  
Valentina Guccini ◽  
Shun Yu ◽  
Michael Agthe ◽  
Korneliya Gordeyeva ◽  
Yulia Trushkina ◽  
...  
Keyword(s):  
Osmotic Dehydration ◽  
Cellulose Nanofibers ◽  
Gel Formation ◽  
Fractal Structures ◽  
Maximum Order ◽  
X Ray ◽  
Nematic Ordering ◽  
X Ray Scattering ◽  
Wide Range

<div><div><p>The formation and characterization of nematically-ordered CNF materials (maximum order parameter f ≈ 0.8) has been studied by polarized optical microscopy, small angle x-ray scattering (SAXS), and rheological measurements as a function of CNF concentration. The wide range of CNF concentrations, from 0.5 wt% to 4.9 wt%, is obtained using osmotic dehydration with PEG. At concentrations >1.05 wt% the CNF suspension crosses an isotropic-anisotropic transition that is accompanied by a dramatic increase of the optical birefringence. The resulting nanostructures are depicted by a hierarchical model with mass fractal structures that converge into co-existing nematically-ordered regions and network-like regions, in which the correlation distances decrease upon increasing concentration. The use of rapid, upscaleble osmotic dehydration is an effective method to increase the concentration of CNF suspensions while partly circumventing the gel formation. The facile formation of highly ordered fibers can result in materials with interesting macroscopic properties.</p></div></div>

scholarly journals Inducing Nematic Ordering of Cellulose Nanofibers using Osmotic Dehydration

2018 ◽  
Author(s):  
Valentina Guccini ◽  
Shun Yu ◽  
Michael Agthe ◽  
Korneliya Gordeyeva ◽  
Yulia Trushkina ◽  
...  
Keyword(s):  
Osmotic Dehydration ◽  
Cellulose Nanofibers ◽  
Gel Formation ◽  
Fractal Structures ◽  
Maximum Order ◽  
X Ray ◽  
Nematic Ordering ◽  
X Ray Scattering ◽  
Wide Range

<div><div><p>The formation and characterization of nematically-ordered CNF materials (maximum order parameter f ≈ 0.8) has been studied by polarized optical microscopy, small angle x-ray scattering (SAXS), and rheological measurements as a function of CNF concentration. The wide range of CNF concentrations, from 0.5 wt% to 4.9 wt%, is obtained using osmotic dehydration with PEG. At concentrations >1.05 wt% the CNF suspension crosses an isotropic-anisotropic transition that is accompanied by a dramatic increase of the optical birefringence. The resulting nanostructures are depicted by a hierarchical model with mass fractal structures that converge into co-existing nematically-ordered regions and network-like regions, in which the correlation distances decrease upon increasing concentration. The use of rapid, upscaleble osmotic dehydration is an effective method to increase the concentration of CNF suspensions while partly circumventing the gel formation. The facile formation of highly ordered fibers can result in materials with interesting macroscopic properties.</p></div></div>

Quantification of Starch Order in Physically Modified Rice Flours Using Small-Angle X-ray Scattering (SAXS) and Fourier Transform Infrared (FT-IR) Spectroscopy

2021 ◽  
pp. 000370282110282
Author(s):  
Daitaro Ishikawa ◽  
Jiamin Yang ◽  
Tomoyuki Fujii
Keyword(s):  
Infrared Spectroscopy ◽  
Small Angle ◽  
Water Sorption ◽  
Order Parameter ◽  
Rice Flour ◽  
Ordered Structure ◽  
X Ray ◽  
Glucose Unit ◽  
X Ray Scattering ◽  
Ray Scattering

The purpose of this study was to understand the ordered structure of starch in rice flour based on a physical modification with non-heating, milling, and water sorption through the structural evaluation of rice flour using small-angle X-ray scattering (SAXS) and infrared spectroscopy within the 4000–100 cm−1 region. The SAXS pattern of the samples with low moisture contents subjected to milling yield a band within the 0.4–0.9 nm−1 of the q range owing to a lamellar repeat of starch with an ordered structure in rice flour. We proposed an order parameter using the intensity of the SAXS band to quantify the order structure of starch in rice flour, and the true density was negatively correlated with the order parameter. Infrared band at 990 cm−1 in COH bending mode applied to the hydroxyl group of C6 shifted to a low wavenumber corresponding to the order parameter. A linear correlation was found between the order parameter and the 990 cm−1 and band at 861 cm−1 owing to COC symmetrical stretching of glycoside bond and CH2 deformation of the glucose unit of starch, 572, 472, and 436 cm−1, owing to the pyranose ring in the glucose unit of starch. The identified infrared bands are effective for quantifying the ordered structure of starch at the lamellar level. When subjected to water sorption, the band position at 990 cm−1 shifted to a higher wavenumber above a water activity of 0.7. This result revealed that the water-induced transition of glass to rubber of starch in rice flour can be clearly evaluated through infrared spectroscopy using the band at 990 cm−1. In addition, the band at 861 cm−1 also shifted to a higher wavenumber, whereas those at 572 and 436 cm−1 did not show a significant shift. These results indicate that water sorption slightly affects the internal structure and may mainly affect the surface of starch.

Smectogenic liquid crystals and nanoparticles: an approach for potential application in photovoltaics

2015 ◽  
Vol 3 (33) ◽  
pp. 8566-8573 ◽  
Author(s):  
A. Meneses-Franco ◽  
A. E. Fierro-Armijo ◽  
P. Romero-Hasler ◽  
L. G. Salamanca-Riba ◽  
L. J. Martínez-Miranda ◽  
...  
Keyword(s):  
Liquid Crystals ◽  
Optical Microscopy ◽  
Potential Application ◽  
Planar Geometry ◽  
Wide Angle ◽  
X Ray Diffraction ◽  
Polarized Optical Microscopy ◽  
X Ray ◽  
X Ray Scattering ◽  
Ray Scattering

We synthesized monomeric liquid crystals, M6R8 and I6R8, and nanoparticles of TiO2, to form a nanocomposite, which was characterized by polarized optical microscopy (POM), DSC and structurally with both wide angle X-ray diffraction and by X-ray scattering using the planar geometry.

Crystallization behavior studied by synchrotron small-angle X-ray scattering of poly (lactic acid)/cellulose nanofibers composites

2017 ◽  
Vol 143 ◽  
pp. 106-115 ◽  
Author(s):  
Thanh Chi Nguyen ◽  
Chaiwat Ruksakulpiwat ◽  
Supagorn Rugmai ◽  
Siriwat Soontaranon ◽  
Yupaporn Ruksakulpiwat
Keyword(s):  
Lactic Acid ◽  
Small Angle ◽  
Crystallization Behavior ◽  
Cellulose Nanofibers ◽  
Poly Lactic Acid ◽  
X Ray ◽  
X Ray Scattering ◽  
Ray Scattering

scholarly journals Study of Dried and Calcinated Ceria Stabilized Zirconia Microspheres Morphology by Small-Angle X-Ray Scattering and Optical Microscopy

2021 ◽  
Vol 47 (1) ◽  
pp. 5
Author(s):  
A. Patriati ◽  
A. Insani ◽  
N. Suparno ◽  
E. Hutamaningtyas ◽  
S. Soontaranoon ◽  
...  
Keyword(s):  
Optical Microscopy ◽  
Small Angle ◽  
Stabilized Zirconia ◽  
X Ray ◽  
X Ray Scattering ◽  
Ray Scattering

Characterization of TEMPO-oxidized cellulose nanofibers in aqueous suspension by small-angle X-ray scattering

2014 ◽  
Vol 47 (2) ◽  
pp. 788-798 ◽  
Author(s):  
Ying Su ◽  
Christian Burger ◽  
Benjamin S. Hsiao ◽  
Benjamin Chu
Keyword(s):  
Cross Section ◽  
Small Angle ◽  
Structural Information ◽  
Rectangular Cross Section ◽  
Aqueous Suspension ◽  
Cellulose Nanofibers ◽  
Weighted Average ◽  
X Ray ◽  
X Ray Scattering ◽  
Ray Scattering

Cellulose nanofibers, extracted from wood pulps using the (2,2,6,6-tetramethylpiperidine-1-yl)oxyl (TEMPO)-mediated oxidation method, are low-cost, sustainable and high-performance materials with potential usage in many applications. The structural information of these cellulose nanofibers in aqueous suspension was characterized by synchrotron small-angle X-ray scattering (SAXS). A simplified ribbon model having a near rectangular cross section was found to give the best fit to the SAXS results. The analytical expression of the ribbon model also led to a higher calculation efficiency compared with the more conventional parallelepiped model. The extracted structural information included the cross-section size and size distribution of the cellulose nanofibers. For example, for nanofibers prepared from the dried pulp of the maritime pine, the size-weighted averages of thickness and width were 3.2 and 12.7 nm, respectively, and the corresponding standard deviations were 2.2 and 5.5 nm, respectively. The scattering results of the size-weighted average of the nanofiber width are also consistent with those determined directly from transmission electron microscopy.

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