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Cellulose carbamate derived cellulose thin films: preparation, characterization and blending with cellulose xanthate

Despite being rather old, the Viscose process still is the most important and frequently used technology for the production of regenerated wood based fibers with annual production volumes exceeding 3.5 million tons, mainly for the textile industry.*

However, there are several environmental drawbacks of this technology. For instance, the necessity to use CS2 to form the cellulose precursor material (cellulose xanthate, CX), as well as the development of volatile sulfur containing compounds (e.g. H2S, COS) during the regeneration procedure requires complex recovery technologies, which manifest into higher prices of the final fiber products.*

Another technology that has raised attention in recent years is the Carbacell process. The Carbacell process relies on cellulose carbamate (CC), which is easily obtained by reacting cellulose with urea. CC is soluble in cold alkali and can be subjected to wet spinning processes similar to those in viscose plants.*

In their article: “Cellulose carbamate derived cellulose thin films: preparation, characterization and blending with cellulose xanthate” Michael Weißl, Mathias Andreas Hobisch, Leena Sisko Johansson, Kay Hettrich, Eero Kontturi, Bert Volkert and Stefan Spirk introduce a new system for manufacturing cellulose thin films based on ecofriendly CC. *

Since CC is water soluble, the use of organic solvents is omitted compared to the other often employed cellulose derivative, TMSC. In addition, CC can be synthesized in large scale via environmentally friendly procedures. The regeneration process itself does not require any additional treatment but is induced by increasing the NaOH concentration during the spin-coating via evaporation of the water, as confirmed by IR and XPS spectroscopy.*

Atomic Force Microscopy in tapping mode using a NanoWorld Arrow-NCR AFM probe was employed to gain further information about the surface morphology and structure of the CC films.

Fig. 3 from “*Cellulose carbamate derived cellulose thin films: preparation, characterization and blending with cellulose xanthate*” by Michael Weißl et al.:
2 × 2 µm2 AFM height (upper row) and phase (lower row) images of CC based thin films after spin coating and rinsing with water; starting with concentrations from 1.0 to 1.5, 2.0 and 2.5 wt%

*Michael Weißl, Mathias Andreas Hobisch, Leena Sisko Johansson, Kay Hettrich, Eero Kontturi, Bert Volkert, Stefan Spirk
Cellulose carbamate derived cellulose thin films: preparation, characterization and blending with cellulose xanthate
Cellulose, August 2019, Volume 26, Issue 12, pp 7399–7410
Doi: https://doi.org/10.1007/s10570-019-02600-z

Please follow this external link to read the full article: h ttps://link.springer.com/article/10.1007%2Fs10570-019-02600-z

Open Access: The paper « Cellulose carbamate derived cellulose thin films: preparation, characterization and blending with cellulose xanthate » by Michael Weißl, Mathias Andreas Hobisch, Leena Sisko Johansson, Kay Hettrich, Eero Kontturi, Bert Volkert and Stefan Spirk is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.

A Short Peptide Hydrogel with High Stiffness Induced by 310‐Helices to β‐Sheet Transition in Water

In the article “A Short Peptide Hydrogel with High Stiffness Induced by 3₁₀‐Helices to β‐Sheet Transition in Water” by Shu Hui Hiew, Harini Mohanram, Lulu Ning, Jingjing Guo, Antoni Sánchez‐Ferrer, Xiangyan Shi, Konstantin Pervushin, Yuguang Mu, Raffaele Mezzenga and Ali Miserez, a short biomimetic peptide composed of eight amino acid residues derived from squid sucker ring teeth proteins is demonstrated to form hydrogel in water without any cross‐linking agent or chemical modification and exhibits a stiffness on par with the stiffest peptide hydrogels.
Their study broadens the range of secondary structures available to create supramolecular hydrogels, and introduces 3_10‐helices as transient building blocks for gelation via a 3_10‐to‐β‐sheet conformational transition.*

The AFM images presented in this study were obtained in soft tapping mode using NanoWorld Pointprobe® NCSTR AFM probes.

*Shu Hui Hiew, Harini Mohanram, Lulu Ning, Jingjing Guo, Antoni Sánchez‐Ferrer, Xiangyan Shi, Konstantin Pervushin, Yuguang Mu, Raffaele Mezzenga, Ali Miserez
A Short Peptide Hydrogel with High Stiffness Induced by 3_10‐Helices to β‐Sheet Transition in Water
Advanced Science 2019, 1901173
Doi: https://doi.org/10.1002/advs.201901173

Please follow this external link to read the full article: https://onlinelibrary.wiley.com/doi/full/10.1002/advs.201901173

Open Access: The article « A Short Peptide Hydrogel with High Stiffness Induced by 3₁₀‐Helices to β‐Sheet Transition in Water » ” by Shu Hui Hiew, Harini Mohanram, Lulu Ning, Jingjing Guo, Antoni Sánchez‐Ferrer, Xiangyan Shi, Konstantin Pervushin, Yuguang Mu, Raffaele Mezzenga and Ali Miserez is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other thirdparty material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.

Ultra-high resolution imaging of thin films and single strands of polythiophene using atomic force microscopy

Real-space images of polymers with sub-molecular resolution could provide valuable insights into the relationship between morphology and functionality of polymer optoelectronic devices, but their acquisition is problematic due to perceived limitations in atomic force microscopy (AFM).*

In the article “Ultra-high resolution imaging of thin films and single strands of polythiophene using atomic force microscopy” Vladimir V. Korolkov, Alex Summerfield, Alanna Murphy, David B. Amabilino, Kenji Watanabe, Takashi Taniguchi and Peter H. Beton show that individual thiophene units and the lattice of semicrystalline spin-coated films of polythiophenes (PTs) may be resolved using AFM under ambient conditions through the low-amplitude (≤ 1 nm) excitation of higher eigenmodes of a cantilever.*

They authors demonstrate that the use of higher eigenmodes in tapping-mode ambient AFM can be successfully employed to characterize both individual polymer strands down to a single-atom level and also the ordering of a semi-crystalline polymer with technological relevance. The combination of AFM and solution deposition provides a simple and high-resolution approach to characterizing the structure of polymers.*

The use of NanoWorld Arrow-UHF high frequency AFM probes at their first eigenmode of ~1.4 MHz is mentioned.*

Figure 1a from “Ultra-high resolution imaging of thin films and single strands of polythiophene using atomic force microscopy” by V. Korolkov et al.: High-resolution AFM images of P3DT adsorbed on the surface of hBN. a An overview height scan of P3DT assembled on hBN, scan rate 6.51 Hz, 1024 × 1024 px; inset shows lattice frequency shift image of hBN acquired in FM-AFM tapping mode, scan rate 39 Hz, 512 × 512 px; both images were acquired with the same Arrow UHF probe oscillating at fundamental frequency of 1.42 MHz.

*Vladimir V. Korolkov, Alex Summerfield, Alanna Murphy, David B. Amabilino, Kenji Watanabe, Takashi Taniguchi and Peter H. Beton
Ultra-high resolution imaging of thin films and single strands of polythiophene using atomic force microscopy
Nature Communications, volume 10, Article number: 1537 (2019)
doi: https://doi.org/10.1038/s41467-019-09571-6

Please follow this external link to read the full article: https://rdcu.be/bLSdL

Open Access: The article « Ultra-high resolution imaging of thin films and single strands of polythiophene using atomic force microscopy » by Vladimir V. Korolkov, Alex Summerfield, Alanna Murphy, David B. Amabilino, Kenji Watanabe, Takashi Taniguchi and Peter H. Beton is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.