scholarly journals Highly Hydrophobic Organosilane-Functionalized Cellulose: A Promising Filler for Thermoplastic Composites

Materials ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2005
Author(s):  
Pavel Cerny ◽  
Petr Bartos ◽  
Pavel Kriz ◽  
Pavel Olsan ◽  
Petr Spatenka
Keyword(s):  
Functional Groups ◽  
Photoelectron Spectroscopy ◽  
Microwave Plasma ◽  
Treatment Time ◽  
Cellulose Fibers ◽  
Thermoplastic Composites ◽  
Process Gas ◽  
Highly Hydrophobic ◽  
Oxygen Process ◽  
Polypropylene Powder

The aim of this work is to design and optimize the process of functionalization of cellulose fibers by organosilane functional groups using low-pressure microwave plasma discharge with hexamethyldisiloxane (HMDSO) precursor in order to prepare a compatible hydrophobic filler for composites with nonpolar thermoplastic matrices. Particular attention was paid to the study of agglomeration of cellulose fibers in the mixture with polypropylene. In our contribution, the dependence of the surface wettability on used process gas and treatment time was investigated. Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) analyses were applied to characterize the surface morphology and chemical composition of the cellulose fibers. It was observed that the plasma treatment in oxygen process gas led to the functionalization of cellulose fibers by organosilane functional groups without degradation. In addition, the treated cellulose was highly hydrophobic with water contact angle up to 143°. The use of treated cellulose allowed to obtain a homogeneous mixture with polypropylene powder due to the significantly lower tendency of the functionalized cellulose fibers to agglomerate.

One-step Synthesis of Carbon Nanotubes Network with Rich Oxygenated Functional Groups via Microwave Plasma in Atmospheric Pressure

MRS Advances ◽  
2020 ◽  
Vol 5 (52-53) ◽  
pp. 2679-2684
Author(s):  
Dashuai Li ◽  
Ling Tong ◽  
Bo Gao
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Functional Groups ◽  
Photoelectron Spectroscopy ◽  
Atmospheric Pressure ◽  
Microwave Plasma ◽  
Ethanol Vapor ◽  
Transmission Electron ◽  
Synthesis Of Carbon Nanotubes ◽  
Oxygenated Functional Groups

AbstractAn atmospheric pressure microwave plasma tubular furnace apparatus (MPTF) for the rapid synthesis of carbon nanotubes (CNTs) has been developed. CNTs have been synthesized by an Argon-Hydrogen microwave plasma using ethanol vapor as carbon source with the furnace temperature of 800 °C at the atmospheric pressure. The synthesized CNTs have been analyzed by scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), and are shown to be multi-walled and tangled and chemically connected to form a high-density network with the diameter at the range of 25-70 nm. The measurement of X-ray photoelectron spectroscopy (XPS) indicates that a large number of oxygenated functional groups grown on the surface of CNTs. These properties proved that the CNTs could be utilized as nanoscale templates for various applications.

scholarly journals New Method for Optimization of Polymer Powder Plasma Treatment for Composite Materials

Polymers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 965
Author(s):  
Zuzana Weberová ◽  
Hana Šourková ◽  
Jakub Antoň ◽  
Taťána Vacková ◽  
Petr Špatenka
Keyword(s):  
Composite Materials ◽  
Plasma Treatment ◽  
Photoelectron Spectroscopy ◽  
Treatment Time ◽  
Dissimilar Materials ◽  
Melting Process ◽  
Thermoplastic Composites ◽  
Glass Substrates ◽  
Treatment Conditions ◽  
Effective Development

This paper describes a newly developed testing method for determination of the adhesivity of a film sintered from thermoplastic powder. This method is based on the modified EN 15337 standard. Application of this method enables an effective development of thermoplastic composites with enhanced adhesion between reinforcement and matrix and/or high-quality joints between plastics and dissimilar materials. The proposed method was successfully tested on a series of polyethylene powders treated in the oxygen atmosphere for 0–1200 s. Adhesion to metal and glass substrates in dependence on treatment conditions is described along with powder wettability and X-ray photoelectron spectroscopy analysis. The results show an increase in adhesion to metal by 580% and to glass by 1670% for the longest treatment time, compared to a nontreated powder. Sintering of treated powders revealed a strong influence of treatment time on the melting process. The XPS analysis confirmed the formation of new oxygen groups (C–O, C=O, O–C=O). The method reveals a specific behavior of powders based on treatment conditions, which is crucial for the optimization of plasma treatment for the improved adhesion, applicability of polymer powders, and a development of composite materials.

X-Ray Photoelectron Spectroscopic Studies of Carbon Fiber Surfaces. Part XVI: Core-Level and Valence-Band Studies of Pitch-Based Fibers Electrochemically Treated in Ammonium Carbonate Solution

1992 ◽  
Vol 46 (4) ◽  
pp. 645-651 ◽  
Author(s):  
Yaoming Xie ◽  
Tiejun Wang ◽  
Oliver Franklin ◽  
Peter M. A. Sherwood
Keyword(s):  
Carbon Fiber ◽  
Valence Band ◽  
Functional Groups ◽  
Photoelectron Spectroscopy ◽  
Treatment Time ◽  
Spectroscopic Studies ◽  
Core Level ◽  
Short Treatment ◽  
X Ray ◽  
Band Spectra

DuPont E-120 high-modulus pitch-based carbon fibers were treated electrochemically in 0.5 M (NH4)2CO3 solution under both potentiostatic and galvanostatic modes. X-ray photoelectron spectroscopy (XPS) was used to monitor the chemical changes on the carbon fiber surfaces. Both core-level and valence-band spectra showed that the treatment introduced both oxygen-containing and nitrogen-containing functional groups onto the fiber surfaces, and the mainly oxygen-containing functional groups produced were carbonyl (C=O) type functional groups after longer treatment time. For short treatment time, hydroxide (C-OH) type groups were the dominant functionality, and ether (C-O-C) or epoxide type groups were also formed. The O 2 s peaks from oxygen atoms in the hydroxide functionality and the ether or epoxide groups are well separated in the valence-band spectra; the corresponding O 1 s peaks, however, are not separated in the O 1 s core-region spectra.

scholarly journals α-Cellulose Fibers of Paper-Waste Origin Surface-Modified with Fe3O4 and Thiolated-Chitosan for Efficacious Immobilization of Laccase

Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 581
Author(s):  
Gajanan S. Ghodake ◽  
Surendra K. Shinde ◽  
Ganesh D. Saratale ◽  
Rijuta G. Saratale ◽  
Min Kim ◽  
...  
Keyword(s):  
Enzyme Immobilization ◽  
Photoelectron Spectroscopy ◽  
Cellulose Fibers ◽  
Relative Activity ◽  
Significant Activity ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Laccase Immobilization ◽  
Surface Modified

The utilization of waste-paper-biomass for extraction of important α-cellulose biopolymer, and modification of extracted α-cellulose for application in enzyme immobilization can be extremely vital for green circular bio-economy. Thus, in this study, α-cellulose fibers were super-magnetized (Fe3O4), grafted with chitosan (CTNs), and thiol (-SH) modified for laccase immobilization. The developed material was characterized by high-resolution transmission electron microscopy (HR-TEM), HR-TEM energy dispersive X-ray spectroscopy (HR-TEM-EDS), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FT-IR) analyses. Laccase immobilized on α-Cellulose-Fe3O4-CTNs (α-Cellulose-Fe3O4-CTNs-Laccase) gave significant activity recovery (99.16%) and laccase loading potential (169.36 mg/g). The α-Cellulose-Fe3O4-CTNs-Laccase displayed excellent stabilities for temperature, pH, and storage time. The α-Cellulose-Fe3O4-CTNs-Laccase applied in repeated cycles shown remarkable consistency of activity retention for 10 cycles. After the 10th cycle, α-Cellulose-Fe3O4-CTNs possessed 80.65% relative activity. Furthermore, α-Cellulose-Fe3O4-CTNs-Laccase shown excellent degradation of pharmaceutical contaminant sulfamethoxazole (SMX). The SMX degradation by α-Cellulose-Fe3O4-CTNs-Laccase was found optimum at incubation time (20 h), pH (3), temperatures (30 °C), and shaking conditions (200 rpm). Finally, α-Cellulose-Fe3O4-CTNs-Laccase gave repeated degradation of SMX. Thus, this study presents a novel, waste-derived, highly capable, and super-magnetic nanocomposite for enzyme immobilization applications.

scholarly journals Investigation into the color stripping of the pigment printed cotton fabric using the ozone assisted process: A study on the decolorization and characterization

2021 ◽  
Vol 16 ◽  
pp. 155892502199275
Author(s):  
Ajinkya Powar ◽  
Anne Perwuelz ◽  
Nemeshwaree Behary ◽  
Le vinh Hoang ◽  
Thierry Aussenac ◽  
...  
Keyword(s):  
Cotton Fabric ◽  
Photoelectron Spectroscopy ◽  
Treatment Time ◽  
Pilot Scale ◽  
Chemical Recycling ◽  
X Ray ◽  
Cellulosic Fibers ◽  
Dyeing Process ◽  
Cellulosic Textiles ◽  
Ozonation Process

Color stripping is one of the most convenient ways to rectify the various shade faults occurred during printing or dyeing process of textiles. But, the conventional chemical assisted process poses serious risk of the environmental pollution. Secondly, the chemical recycling of the cellulosic fibers may be disrupted due to the presence of the impurities like colorants, finishes, and the additives in the discarded textiles. So, there is a need to study ways to remove such impurities from the discarded cellulosic textiles in a sustainable manner. This work examines the decolorization of the pigment prints on cellulosic fabrics at pilot scale using an ozone-assisted process. The effect of varying pH, ozone concentration and the treatment time on the decolorization of the pigment prints was optimized using the response surface methodology technique. The effects of ozonation process parameters on the mechanical properties of cellulosic cotton fabric were measured. Decolorization of pigment printed samples was studied with respect to the surface effects by a scanning electron microscopy (SEM), and the chemical removal effects of ozonation treatment were studied using X-ray photoelectron spectroscopy. The possible mechanism regarding the action of ozone for the decolorization is discussed.

X-Ray Photoelectron-Spectroscopic Studies of Carbon Fiber Surfaces. Part IX: The Effect of Microwave Plasma Treatment on Carbon Fiber Surfaces

1989 ◽  
Vol 43 (7) ◽  
pp. 1153-1158 ◽  
Author(s):  
Yaoming Xie ◽  
Peter M. A. Sherwood
Keyword(s):  
Carbon Fiber ◽  
Plasma Treatment ◽  
Photoelectron Spectroscopy ◽  
Prolonged Exposure ◽  
Microwave Plasma ◽  
Spectroscopic Studies ◽  
X Ray ◽  
Fiber Damage ◽  
Surface Functionality ◽  
Fiber Treatment

X-ray photoelectron spectroscopy has been used to monitor the surface chemical changes occurring on type II carbon fibers exposed to air, oxygen, and nitrogen plasmas. In all cases the plasmas caused changes in surface functionality, in terms of both C-O and C-N functionality. Prolonged exposure to the plasmas caused loss of surface functionality for air and oxygen plasmas, and extended treatment caused fiber damage. Plasma treatment of fibers promises to be an effective method of fiber treatment.

Nitriding of yttria-stabilized zirconia in atmospheric pressure microwave plasma

2009 ◽  
Vol 24 (6) ◽  
pp. 2021-2028 ◽  
Author(s):  
R. Milani ◽  
R.P. Cardoso ◽  
T. Belmonte ◽  
C.A. Figueroa ◽  
C.A. Perottoni ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Atmospheric Pressure ◽  
Microwave Plasma ◽  
Plasma Nitriding ◽  
Nitrided Layer ◽  
Zirconium Nitride ◽  
Stabilized Zirconia ◽  
Partially Stabilized Zirconia ◽  
X Ray ◽  
Yttria Partially Stabilized Zirconia

High temperature plasma nitriding of yttria-partially-stabilized zirconia in atmospheric pressure microwave plasma was investigated. The morphological, mechanical, and physicochemical characteristics of the resulting nitrided layer were characterized by different methods, such as optical and scanning electron microscopy, microindentation, x-ray diffraction, narrow resonant nuclear reaction profiling, secondary neutral mass spectrometry, and x-ray photoelectron spectroscopy, aiming at investigating the applicability of this highly efficient process for nitriding of ceramics. The structure of the plasma nitrided layer was found to be complex, composed of tetragonal and cubic zirconia, as well as zirconium nitride and oxynitride. The growth rate of the nitrided layer, 4 µm/min, is much higher than that obtained by any other previous nitriding process, whereas a typical 50% increase in Vickers hardness over that of yttria-partially-stabilized zirconia was observed.

scholarly journals Эволюция физико-химических свойств поверхности GaSb(100) в растворах сульфида аммония

2019 ◽  
Vol 53 (7) ◽  
pp. 908
Author(s):  
М.В. Лебедев ◽  
Т.В. Львова ◽  
А.Л. Шахмин ◽  
О.В. Рахимова ◽  
П.А. Дементьев ◽  
...  
Keyword(s):  
Oxide Layer ◽  
Photoelectron Spectroscopy ◽  
Treatment Time ◽  
Solution Concentration ◽  
Native Oxide ◽  
Semiconductor Surface ◽  
Native Oxide Layer ◽  
Force Microscopy ◽  
Fermi Level Pinning ◽  
Ammonium Sulfide

AbstractVarious conditions of passivation of the GaSb(100) surface by ammonium sulfide ((NH_4)_2S) solutions depending on the solution concentration, solvent, and treatment time are investigated by X-ray photoelectron spectroscopy and atomic-force microscopy. It is shown that treatment of the GaSb(100) surface by any (NH_4)_2S solution leads to removal of the native oxide layer from the semiconductor surface and the formation of a passivating layer consisting of various gallium and antimony sulfides and oxides. The surface with the lowest roughness (RMS = 0.85 nm) is formed after semiconductor treatment with 4% aqueous ammonium sulfide solution for 30 min. Herewith, the atomic concentration ratio Ga/Sb at the surface is ~2. It is also found that aqueous ammonium sulfide solutions do not react with elemental antimony incorporated into the native-oxide layer. The latter causes a leakage current and Fermi-level pinning at the GaSb(100) surface. However, a 4% (NH_4)_2S solution in isopropanol removes elemental antimony almost completely; herewith, the semiconductor surface remains stoichiometric if a treatment duration is up to 13 min.

scholarly journals Effect of synthesis conditions  on  methylene blue adsorption capacity of electrochemically preparated graphene

2020 ◽  
Vol 9 (3) ◽  
pp. 9-14
Author(s):  
Hao Pham Van ◽  
Linh Ha Xuan ◽  
Oanh Phung Thi ◽  
Hong Phan Ngoc ◽  
Huy Nguyen Nhat ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Methylene Blue ◽  
Adsorption Capacity ◽  
Functional Groups ◽  
Photoelectron Spectroscopy ◽  
Graphene Nanosheets ◽  
Electrochemical Exfoliation ◽  
X Ray ◽  
Synthesis Conditions ◽  
Mb Adsorption

This report presents the effect of synthesis conditions on the synthesis of graphene nanosheets via electrochemical exfoliation method for adsorbing methylene blue from aqueous solution. Oxygen-containing functional groups and defects in the material were characterized by Raman and X-ray photoelectron spectroscopy (XPS). As a result, by using voltage of 15 V, (NH4)2SO4 (5%, 250 mL) and KOH (7.5%, 250 mL), the obtained material showed the highest MB adsorption capacity due to the high densities of oxygen-containing groups and defects comparison to other conditions.

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