Polyarylenediphthalides

2017 ◽  
Vol 29 (6) ◽  
pp. 677-690 ◽  
Author(s):  
Vladimir A Kraikin ◽  
Tagir A Yangirov ◽  
Akhnef A Fatykhov ◽  
Valentina P Ivanova ◽  
Elvira A Sedova ◽  
...  
Keyword(s):  
Polymer Chain ◽  
Main Chain ◽  
High Hardness ◽  
Inert Atmosphere ◽  
Diamond Like Carbon ◽  
New Type

The polyheteroarylenes of new type, called polyarylenediphthalides (PADPs), containing two adjacent phthalide groups regularly alternating with aromatic (heteroaromatic) fragments in the main chain have been developed. For obtaining PADPs, two approaches based on the dehalogenation reactions were used. In the first, polycondensation of the pseudo-acids chlorides was carried out that led to the polymers with random stereo configuration of diphthalide groups. In the second, stereospecific PADPs were formed using diastereoisomeric pure halogenated biaryl-3,3′-diphthalides (meso and racemic) as monomers that attach themselves to the growing polymer chain entirely keeping their stereo configuration. The obtained polymers start to soften and decompose at ≈350°C in inert atmosphere. Degradation of PADPs at deep carbonizing stages in the inert atmosphere is followed by formation of foamed coke with increased content of diamond-like carbon that possesses a high hardness (≥8 by Mohs scale).

Synthesis of high hardness, low COF diamond-like carbon using RF-PECVD at room temperature and evaluating its structure using electron microscopy

2017 ◽  
Vol 80 ◽  
pp. 108-112 ◽  
Author(s):  
K. Ankit ◽  
Ashish Varade ◽  
Niranjan Reddy ◽  
Sarmistha Dhan ◽  
M. Chellamalai ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Room Temperature ◽  
High Hardness ◽  
Diamond Like Carbon

MULTILAYERS DIAMOND-LIKE CARBON FILM WITH GERMANIUM BUFFER LAYERS BY PULSED LASER DEPOSITION

2017 ◽  
Vol 24 (02) ◽  
pp. 1750014 ◽  
Author(s):  
Y. CHENG ◽  
Y. M. LU ◽  
Y. L. GUO ◽  
G. J. HUANG ◽  
S. Y. WANG ◽  
...  
Keyword(s):  
Critical Load ◽  
Carbon Film ◽  
High Hardness ◽  
Buffer Layers ◽  
Diamond Like Carbon ◽  
Dlc Film ◽  
Diamond Like Carbon Film ◽  
Film Hardness ◽  
Protective Films ◽  
Germanium Substrate

Multilayer diamond-like carbon film with germanium buffer layers, which was composed of several thick DLC layers and thin germanium island “layers” and named as Ge-DLC film, was prepared on the germanium substrate by ultraviolet laser. The Ge-DLC film had almost same surface roughness as the pure DLC film. Hardness of the Ge-DLC film was above 48.1[Formula: see text]GPa, which was almost the same as that of pure DLC film. Meanwhile, compared to the pure DLC film, the critical load of Ge-DLC film on the germanium substrate increased from 81.6[Formula: see text]mN to 143.8[Formula: see text]mN. Moreover, Ge-DLC film on germanium substrates had no change after fastness tests. The results showed that Ge-DLC film not only kept high hardness but also had higher critical load than that of pure DLC film. Therefore, it could be used as practical protective films.

DIAMOND-LIKE CARBON: A NEW MATERIAL BASE FOR NANO-ARCHITECTURES

COSMOS ◽  
2008 ◽  
Vol 04 (02) ◽  
pp. 203-234 ◽  
Author(s):  
XIJUN LI ◽  
DANIEL H. C. CHUA
Keyword(s):  
Carbon Film ◽  
High Hardness ◽  
Diamond Like Carbon ◽  
Protective Film ◽  
Material Base ◽  
Wear Resistant Coatings ◽  
Novel Material ◽  
New Material ◽  
High Fraction ◽  
Mechanical Devices

Diamond-like carbon (DLC) is a form of amorphous carbon which has high fraction of sp3 hybridization. Due to its nature of sp3 bonding, diamond-like carbon has been shown to have excellent properties similar to that of diamond. This includes high hardness, excellent wear-resistance, large modulus and chemically inert. Traditional applications include wear resistant coatings and protective film. This article intends to review the synthesis and material properties of diamond-like carbon as well as its potential as a novel material for applications in nano-architecture and nano-mechanical devices. An introduction into metal-dopants in diamond-like carbon film will be briefly mentioned as well as techniques on the design and fabrication of this material.

Fluctuation Microscopy Studies of Amorphous Diamond-Like Carbon Films

2000 ◽  
Vol 6 (S2) ◽  
pp. 432-433
Author(s):  
X. Chen ◽  
J. M. Gibson ◽  
J. Sullivan
Keyword(s):  
Electronic Devices ◽  
High Hardness ◽  
Carbon Films ◽  
Optical Coatings ◽  
Diamond Like Carbon ◽  
Electron Loss ◽  
Negative Electron Affinity ◽  
Chemical Inertness ◽  
Potential Applications ◽  
Key Questions

Hydrogen-free amorphous diamond-like carbon films have stimulated great interest because of their useful properties, such as high hardness, chemical inertness, thermal stability, wide optical gap, and negative electron affinity[l]. Consequently, they may have various potential applications in mechanical and optical coatings, MEMS systems, chemical sensors and electronic devices. Amorphous diamond-like carbon films often contains significant amounts of four-fold or sp3 bonded carbon, in contrast to amorphous carbon films prepared by evaporation or sputtering which consist mostly of three-fold or sp2 bonded carbon. The ratio and the structure configurations of these three-fold and four-fold carbon atoms certainly decide the properties of these amorphous diamond-carbon films. Although the ratio of three-fold and four-fold carbon has been studied with Raman spectroscopy and electron-loss-energy spectroscopy, very little has been understood regarding key questions such as how the three-fold and the four-fold carbon atoms are integrated in the film, and what structures those three-fold carbon atoms take.

Effect of Microshot Peening on Surface Characteristics of Spring Steel

2010 ◽  
Vol 654-656 ◽  
pp. 374-377
Author(s):  
Yasunori Harada ◽  
Koji Yoshida
Keyword(s):  
Residual Stress ◽  
Shot Peening ◽  
Compressive Residual Stress ◽  
Cast Steel ◽  
High Hardness ◽  
Surface Characteristics ◽  
Spring Steel ◽  
Cemented Carbide ◽  
High Carbon ◽  
New Type

Shot peening is a surface treatment that improves the performance of engineering components. In conventional shot peening, the medium consists of small spheres, which are usually made of high-carbon cast steel; the diameter of the spheres is in the range from 0.3 to 1.2mm. More recently, however, a new type of microshot has been developed to enhance the peening effect. The diameter of the spheres in the new medium is in the range from 0.02 to 0.15mm. In the present study, the effect of microshot peening on the surface characteristics of spring steel was investigated. The injection method of the microshot was of the compressed air type. The microshots of 0.1mm diameter were high-carbon cast steel and cemented carbide, and the workpiece used was the commercially spring steel JIS-SUP10. The surface roughness, hardness and compressive residual stress of the peened workpieces were measured. The surface layer of the workpieces was sufficiently deformed by microshot peening. A high hardness or residual stress was observed near the surface. The use of hard microshots such as cemented carbide was found to cause a significantly enhanced peening effect for spring steel.

Effects of Copper Interlayer and Annealing on Structure and Mechanical Properties of Diamond-Like Carbon Films by Cathode Arc Evaporation

2012 ◽  
Vol 629 ◽  
pp. 25-31
Author(s):  
Bing Zhou ◽  
Xiao Hong Jiang ◽  
A.V. Rogachev ◽  
Rui Qi Shen
Keyword(s):  
Mechanical Properties ◽  
Annealing Temperature ◽  
Morphological Characteristics ◽  
High Hardness ◽  
Carbon Films ◽  
Element Distribution ◽  
Diamond Like Carbon ◽  
Bilayer Films ◽  
Cathode Arc ◽  
Cu Interlayer

Diamond-like carbon (DLC) bilayer films with Cu interlayer were prepared on silicon substrate by direct-current and pulsed cathode arc plasma technique, and annealed at various temperatures in vacuum. Structure, morphology and mechanical properties of the bilayer films were investigated by Raman spectroscopy, Auger electron spectroscopy, scanning electron microscopy and atomic force microscopy, surface profilometer and Vickers sclerometer. The results show that Cu interlayer changes the bilayer microstructure, including the thickness and element distribution of diffusion layer, the relative fraction of sp3/sp2bonding and growth model of bilayer. A simple three-layer model was used to describe the interdiffusion between Cu and C layer. Cu interlayer could be more effective against graphitization upon annealing. Morphological characteristics of the films were studied by analyzing the surface features of substrate. Cu/DLC bilayer exhibits highly dispersed nano-agglomerates with smaller size on the surface due to low surface energy of Cu interlayer. The stress and hardness of the films were affected accordingly. Cu/DLC bilayer shows a relatively high hardness at low annealing temperature but the stress almost no change. By changing Cu interlayer and annealing temperature, excellent DLC films could be designed for the protective, hard, lubricating and wear resistant coatings on mechanical, electronic and optical applications.

Synthesis of high hardness IR optical coating using diamond-like carbon by PECVD at room temperature

2017 ◽  
Vol 78 ◽  
pp. 39-43 ◽  
Author(s):  
Ankit K. ◽  
Ashish Varade ◽  
Niranjan Reddy K. ◽  
Sarmistha Dhan ◽  
Chellamalai M. ◽  
...  
Keyword(s):  
Room Temperature ◽  
High Hardness ◽  
Diamond Like Carbon ◽  
Optical Coating

Novel Polymer Electrolytes Based on Amorphous Poly(ether−ester)s Containing 1,4,7-Trioxanonyl Main Chain Units. Ionic Conductivity versus Polymer Chain Mobility

1999 ◽  
Vol 32 (10) ◽  
pp. 3314-3324 ◽  
Author(s):  
I. J. A. Mertens ◽  
M. Wübbenhorst ◽  
W. D. Oosterbaan ◽  
L. W. Jenneskens ◽  
J. van Turnhout
Keyword(s):  
Ionic Conductivity ◽  
Polymer Chain ◽  
Polymer Electrolytes ◽  
Main Chain ◽  
Chain Mobility ◽  
Ether Ester

scholarly journals DLC Coatings on Spherical Elements of HIP Endoprostheses

2018 ◽  
Vol 2 (3) ◽  
pp. 41-47
Author(s):  
V. V. Vasylyev ◽  
V. E. Strel’nitskij ◽  
V. B. Makarov ◽  
M. A. Skoryk ◽  
G. O. Lazarenko
Keyword(s):  
Hip Joint ◽  
High Hardness ◽  
Plasma Source ◽  
Hard Coatings ◽  
Vacuum Arc ◽  
Diamond Like Carbon ◽  
Dlc Coatings ◽  
Dlc Coating ◽  
High Adhesion ◽  
High Level

Abstract Hard coatings are increasingly being used in medicine to protect metal endoprostheses The experimental process for the high-productive synthesis of high-quality diamond-like carbon (DLC) coatings with high hardness and a sufficiently high level of adhesion to the spherical shaped parts of the hip joint made from the stainless steel or cobalt-chrome alloy have been developed. DLC coating deposition was performed by vacuum-arc method from a high-productive source of the filtered vacuum-arc carbon plasma of rectilinear type with a "magnetic island". The high degree of thickness uniformity in the coating on the head of the hip joint with a high adhesion to the metal joint base was developed. Modernization of the vacuum arc plasma source allowed to accelerate the cathode spot motion, exclude substrate overheating and increase the diamond-like carbon hardness up to 30-40 GPa. The high adhesion level was achieved as a result of the high voltage pulsed of substrate bias potential use and multilayer architecture of DLC coating. The DLC coating on the heads of hip endoprosthesis did not peel off when boiling endoprosthesis or when immersing it into the liquid nitrogen.

scholarly journals In vivo biocompatibility of diamond-like carbon films containing TiO2 nanoparticles for biomedical applications

2021 ◽  
Vol 32 (9) ◽  
Author(s):  
C. C. Wachesk ◽  
S. H. Seabra ◽  
T. A. T. Dos Santos ◽  
V. J. Trava-Airoldi ◽  
A. O. Lobo ◽  
...  
Keyword(s):  
Inflammatory Process ◽  
Antimicrobial Properties ◽  
Chemical Vapor ◽  
High Hardness ◽  
Carbon Films ◽  
High Wear Resistance ◽  
Diamond Like Carbon ◽  
Dlc Coatings ◽  
Inflammatory Reactions

AbstractHybrid diamond-like carbon (DLC) with incorporated titanium dioxide (TiO2) nanoparticle coatings have low friction coefficient, high wear resistance, high hardness, biocompatibility, and high chemical stability. They could be employed to modify biomedical alloys surfaces for numerous applications in biomedical engineering. Here we investigate for the first time the in vivo inflammatory process of DLC coatings with incorporated TiO2 nanoparticles. TiO2-DLC films were grown on AISI 316 stainless-steel substrates using plasma-enhanced chemical vapor deposition. The coated substrates were implanted in CF1 mice peritoneum. The in vivo cytotoxicity and biocompatibility of the samples were analyzed from macrophage lavage. Analysis in the first weeks after implantation could be helpful to evaluate the acute cytotoxicity generated after a possible inflammatory process. The in vivo results showed no inflammatory process. A significant increase in nitric oxide production on the uncoated substrates was confirmed through cytometry, and the coated substrates demonstrated biocompatibility. The presence of TiO2 nanoparticles enhanced the wound healing activity, due to their astringent and antimicrobial properties. DLC and TiO2-DLC coatings were considered biocompatible, and the presence of TiO2 nanoparticles reduced the inflammatory reactions, increasing DLC biocompatibility.

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