Oxygen plasma treatment of bamboo fibers (BF) and its effects on the static and dynamic mechanical properties of BF-unsaturated polyester composites

Holzforschung ◽  
2015 ◽  
Vol 69 (4) ◽  
pp. 449-455 ◽  
Author(s):  
Wendi Liu ◽  
Tingting Chen ◽  
Tianshun Xie ◽  
Fuwen Lai ◽  
Renhui Qiu
Keyword(s):  
Plasma Treatment ◽  
Photoelectron Spectroscopy ◽  
Interfacial Adhesion ◽  
Oxygen Plasma ◽  
Unsaturated Polyester ◽  
Flexural Modulus ◽  
Oxygen Plasma Treatment ◽  
X Ray ◽  
Dynamic Mechanical ◽  
Bamboo Fibers

Abstract A novel method for the preparation of bamboo fibers (BF) has been investigated that includes crushing, rolling, and other combing techniques with 1,4-butanediol as a dispersant. The fibers were treated by oxygen plasma to improve their interfacial adhesion to unsaturated polyester (UPE) resins. Composites were prepared from the plasma treated fibers (BFtr) and UPE by hand lay-up compression molding. BFtr significantly increased the tensile strength, flexural strength, and flexural modulus of the resulting BF-UPE composites. Dynamic mechanical analysis indicated that the plasma treatment essentially increased the storage modulus and glass transition temperature of the composites. The damping parameter of the composites showed a decreasing trend in the glassy region, while the opposite was true for the rubbery region. X-ray diffraction analysis indicated that the treatment did not change the crystal structures within the fibers but increased slightly their crystallinity indices. X-ray photoelectron spectroscopy analysis revealed that the surface of BFtr had a higher oxygen concentration and oxygen/carbon ratio than that of BF. The scanning electron microscopy graphs of the tensile-fractured surface of the composites demonstrated an improved interfacial adhesion between BFtr and UPE resins.

Effect of oxygen plasma treatment on the performance of recessed AlGaN/GaN Schottky barrier diodes

2021 ◽  
Author(s):  
Wei Mao ◽  
shihao Xu ◽  
Haiyong Wang ◽  
Cui Yang ◽  
ShengLei Zhao ◽  
...  
Keyword(s):  
Plasma Treatment ◽  
Schottky Barrier ◽  
Photoelectron Spectroscopy ◽  
Oxygen Plasma ◽  
Oxygen Plasma Treatment ◽  
Surface Oxide Layer ◽  
Schottky Barrier Diodes ◽  
X Ray ◽  
Current Collapse ◽  
Effect Of Oxygen

Abstract The treatment effect of the oxygen plasma on the performance of recessed AlGaN/GaN Schottky barrier diodes has been investigated. After the oxygen plasma treatment, the turn-on voltage and reverse leakage current are slightly changed, while the current collapse could be effectively mitigated. The X-ray photoelectron spectroscopy results suggest that a thin surface oxide layer is formed by the oxygen plasma treatment, which is responsible for the reduced current collapse. In addition, the device with oxygen plasma treatment has a relatively more inhomogeneous barrier height.

Effect of fiber modification with 3-isopropenyl-dimethylbenzyl isocyanate (TMI) on the mechanical properties and water absorption of hemp-unsaturated polyester (UPE) composites

Holzforschung ◽  
2014 ◽  
Vol 68 (3) ◽  
pp. 265-271 ◽  
Author(s):  
Wendi Liu ◽  
Tingting Chen ◽  
Renhui Qiu
Keyword(s):  
Photoelectron Spectroscopy ◽  
Interfacial Adhesion ◽  
Water Resistance ◽  
Unsaturated Polyester ◽  
Flexural Modulus ◽  
Dibutyltin Dilaurate ◽  
Hemp Fibers ◽  
Fiber Modification ◽  
X Ray ◽  
Ft Ir

Abstract Hemp fibers were modified with 3-isopropenyl-dimethylbenzyl isocyanate (TMI), in presence of dibutyltin dilaurate (DBT) as a catalyst. Then reinforced hemp-unsaturated polyester (UPE) composites were prepared with modified fibers by means of hand lay-up compression molding. The fiber treatments significantly increased the tensile strength (TS), flexural strength (FS), and water resistance of the resulting composites, while their flexural modulus (FM) was not influenced. The tensile-fractured surfaces of the composites were observed by SEM and the images revealed that fiber treatments significantly improved the interfacial adhesion between hemp fibers and UPE resins. FT-IR spectra and X-ray photoelectron spectroscopy (XPS) analysis indicated that the treated-fibers were partly covalently bound to TMI.

Surface modification of polyimide fibers by oxygen plasma treatment and interfacial adhesion behavior of a polyimide fiber/epoxy composite

2017 ◽  
Vol 24 (4) ◽  
pp. 477-484 ◽  
Author(s):  
Xuyang Sun ◽  
Junfeng Bu ◽  
Weiwei Liu ◽  
Hongqing Niu ◽  
Shengli Qi ◽  
...  
Keyword(s):  
Free Energy ◽  
Plasma Treatment ◽  
Surface Free Energy ◽  
Photoelectron Spectroscopy ◽  
Interfacial Adhesion ◽  
Oxygen Plasma ◽  
Dynamic Contact Angle ◽  
Epoxy Composites ◽  
Oxygen Plasma Treatment ◽  
Adhesion Properties

AbstractOxygen plasma was used to enhance the surface behavior of polyimide (PI) fibers and PI fiber-reinforced epoxy composites were prepared in our present work. The effects of plasma treating times on the surface properties of PI fiber and the interfacial adhesion of PI fiber/epoxy composites were investigated. Surface chemical composition, surface morphologies and surface free energy of the fibers were characterized by X-ray photoelectron spectroscopy, scanning electron microscopy and dynamic contact angle analysis, respectively. The results suggest that some oxygen functional groups were introduced onto PI fiber surfaces, and the surface roughness of fibers was enhanced. Resultantly, the surface free energy of fibers and the interfacial adhesion of composites were improved by the oxygen plasma treatment. The interlaminar shear strength of the composites increased to 70 MPa when the fibers were treated for 10 min, which proved good interfacial adhesion properties.

scholarly journals The Amorphization of Monolayer MoS2 Induced by Strong Oxygen Plasma Treatment

2019 ◽  
Vol 26 (2) ◽  
pp. 143-146
Author(s):  
Jian-Ling MENG ◽  
Jian-Qi ZHU ◽  
Shun-Tian JIA ◽  
Xiao REN
Keyword(s):  
Visible Light ◽  
Plasma Treatment ◽  
Raman Spectra ◽  
Photoelectron Spectroscopy ◽  
Oxygen Plasma ◽  
Oxygen Plasma Treatment ◽  
Visible Light Photocatalysis ◽  
Monolayer Mos2 ◽  
X Ray ◽  
Raman Modes

By strong oxygen plasma treatment on monolayer MoS2, we observe the disappearance of the Raman modes of MoS2. We propose the hypothesis that the state of MoS2 translates from crystal to amorphous after strong oxygen plasma treatment. The evidences of no MoO3 formation shown by Raman spectra and the appearance of the Mo6+ peak and decreased O concentration shown by X-ray photoelectron spectroscopy support our hypothesis. The amorphization of monolayer MoS2 is further confirmed by the quenching of photoluminescence (PL) and the disappearance of two absorption peaks related to A, B exciton which demonstrates the disordered bandgap. Finally, we found that the amorphous MoS2 can improve the absorption fraction at the visible light (500~ 750 nm) which is potential for future visible light photocatalysis.

Investigation of bamboo pulp fiber-reinforced unsaturated polyester composites

Holzforschung ◽  
2015 ◽  
Vol 69 (8) ◽  
pp. 967-974 ◽  
Author(s):  
Renhui Qiu ◽  
Wendi Liu ◽  
Kaichang Li
Keyword(s):  
Tensile Strength ◽  
Flexural Strength ◽  
Photoelectron Spectroscopy ◽  
Unsaturated Polyester ◽  
Flexural Modulus ◽  
Pulp Fiber ◽  
Pulp Fibers ◽  
Chemical Pulp ◽  
Bamboo Pulp ◽  
Bamboo Fibers

Abstract Mechanical pulp fibers (MPFs) and chemical pulp fibers (CPFs) from moso bamboo have been characterized in terms of their length and width distributions, and their reinforcing effects in unsaturated polyester (UPE) composites have also been investigated. CPF-UPE composites had much higher tensile strength, flexural strength, and flexural modulus than MPF-UPE composites. CPF-UPE composites also absorbed less water than MPF-UPE composites. Treatments of the fibers with a combination of 1,6-diisocyanatohexane (DIH) and 2-hydroxyethyl acrylate (HEA) significantly increased the tensile strength, flexural strength, flexural modulus, and water resistance of the resulting composites. Fourier transform infrared and X-ray photoelectron spectroscopy analyses indicated that DIH-HEA was bound onto bamboo fibers (BFs) via carbamate linkages. The scanning electron microscopy images of the tensile-fractured surfaces of the composites revealed that the DIH-HEA treatments for BFs greatly improved the interfacial adhesion between the fibers and UPE resins.

Influence of Oxygen Plasma Treatment on Surface Properties of Armos Fiber

2008 ◽  
Vol 373-374 ◽  
pp. 430-433 ◽  
Author(s):  
Ping Chen ◽  
Jing Wang ◽  
Cheng Shuang Zhang ◽  
Chun Lu ◽  
Zhen Feng Ding ◽  
...  
Keyword(s):  
Surface Energy ◽  
Plasma Treatment ◽  
Functional Groups ◽  
Interfacial Adhesion ◽  
Oxygen Plasma ◽  
Treatment Time ◽  
Fiber Surface ◽  
Aramid Fiber ◽  
Oxygen Plasma Treatment ◽  
Polar Functional Groups

Armos fiber (F-12 aramid fiber in paper) was provided with broad application foreground as reinforcement material for advanced composites in aviation and spaceflight field, due to its outstanding properties, such as high modulus, high strength, high temperature resistance, erosion resistance and so on. However, the exertion of property was still limited by slippery surface, low surface energy and weak interfacial adhesion performance. In this study, the effects of oxygen plasma treatment time on polar functional groups introduced onto the fiber surface, surface free energy and surface topographic images were discussed by X-ray photoelectron spectroscopy (XPS) analysis, dynamic contact angle analysis system (DCA) and atomic force microscopy (AFM), respectively. It was found that the content of oxygen element and polar functional groups on fiber surface were all increased obviously after oxygen plasma treatment. The content of oxygen element on surface for untreated F-12 aramid fiber was 11.13%, while it increased to 15.20% after oxygen plasma treatment for 10 min; The content of polar functional groups on surface for untreated F-12 aramid fiber was 28.14%, while it increased to 38.11% after oxygen plasma treatment for 10 min. The polar component (γp) of fiber surface energy increased sharply from 6.82 mN/m to 36.68 mN/m after 10 min plasma treatment, the total surface free energy was increased from 46.26 mN/m to 64.66 mN/m.The results indicated that oxygen plasma treatment had introduced a large amount of reactive functional groups onto the fiber surface, and these groups can form together as covalent bonding to improve the surface wettability and increase the surface energy of fibers. At the same time, oxygen plasma treatment was able to generate a mass of bulges and grooves on F-12 aramid fiber surface, which had an active effect on increasing the chemical bond and mechanical function between fiber and resin and enhancing the interfacial adhesion performance of composite. The fiber surface grooves had been increased with the time prolonging before 10 min while decreased after 10 min, the results maybe relate to partial organic on fiber surface melting. It had an adverse effect on the interfacial adhesion properties of composite. Therefore, the optimum plasma treatment time was between 5 min and 10 min.

Improvement in the Activation Efficiency of Implanted Si in GaAs using Oxygen Plasma Pretreatment

1992 ◽  
Vol 259 ◽  
Author(s):  
Jaeshin Cho ◽  
Leszek M. Pawlowicz ◽  
Naresh C. Saha
Keyword(s):  
Photoelectron Spectroscopy ◽  
Oxygen Plasma ◽  
Chemical Vapor ◽  
Gaas Surface ◽  
Oxygen Plasma Treatment ◽  
Surface Conditions ◽  
X Ray ◽  
Plasma Pretreatment ◽  
Activation Efficiency ◽  
Thick Oxide Layer

ABSTRACTWe have investigated the effect of GaAs surface conditions prior to plasma enhanced chemical vapor deposition of a silicon nitride cap on the activation efficiency of implanted Si in GaAs. The oxygen plasma treatment improved the activation efficiency of implanted Si by ∼35% over (1:10) NH4OH:H2O treatment. X-ray photoelectron spectroscopy (XPS) analysis of the oxygen plasma treated GaAs surface indicated the formation of ∼25Å thick oxide layer consisting of Ga2O3, As2O3, As2O5 and elemental As. During the activation anneal, the arsenic-containing oxides react with the GaAs substrate to form Ga2O3 and elemental As. The presence of excess As between the GaAs and the nitride cap film increases the probability that the implanted Si incorporates in the Ga sites over the As sites, and thereby improves the activation efficiency. This surface-related mechanism suggests that the variation in activation efficiency is mostly attributed to variation in surface conditions, and may explain the wide variety of reported values of activation efficiency.

Spectroscopic Analyses of Sputtered Aluminum Oxide Films with Oxygen Plasma Treatments

2019 ◽  
Vol 947 ◽  
pp. 96-100
Author(s):  
Chatpawee Hom-On ◽  
Mati Horprathum ◽  
Pitak Eiamchai ◽  
Sakson Limwichean ◽  
Viyapol Patthanasetakul ◽  
...  
Keyword(s):  
Aluminum Oxide ◽  
Plasma Treatment ◽  
Photoelectron Spectroscopy ◽  
Oxygen Plasma ◽  
Oxide Films ◽  
Oxygen Plasma Treatment ◽  
Lower Plasma ◽  
Spectroscopic Analyses ◽  
Effect Of Oxygen ◽  
Deposited Films

X-ray photoelectron spectroscopy (XPS) and Spectroscopic Ellipsometry (SE) were used to analyse the effect of oxygen plasma treatment on properties of aluminum oxide thin films. The aluminum oxide films were fabricated using a reactive sputtering system. The as-deposited films were treated with oxygen plasma powered by an RF generator. During the plasma treatment, the pressures were set at 1 x 10-1 to 1x 10-2 mbar, while the RF supplied powers at 100 W and 200 W. It was observed that lower plasma powers and higher pressures resulted in smoother films. The O/Al ratio of the films were found to decrease with increasing plasma powers and pressures. The thickness and refractive index of the films were significantly affected by the oxygen plasma treatment process, which could be related to the change in films’ packing density and the etching at the surface.

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