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Nanoparticles Modifications of Textiles Using Plasma Technology
Published in Prashansa Sharma, Devsuni Singh, Vivek Dave, Fundamentals of Nano–Textile Science, 2023
Hend M. Ahmed, Mehawed Abdellatif Mohamed, Faten Hassan Hassan Abdellatif
Cold plasma can be used in other application such as starting radical polymerization, which leads to thin layers’ deposition on wide ranges. To improve the bonding between thin films and biological materials, this process takes place in plasma which offers radical sites and allows covalent polymer in conjunction with the surface of the substrate. The polymers can deposit on the surface placing in between the two electrodes. Polymerization process can occur by ionic or radical process which is initiated by plasma generated by glow discharge. For plasma polymerization, plasma is used as a method to initiate and remain active during the whole polymerization reaction. This results in the formation of initiation sites on both surfaces of the substrate and the monomer. Rather than chemical initiation, the plasma can be used for any functional groups of polymeric precursors to initiate the chain reaction. Highly cross–linked, hole free, and amorphous thin film is
Carbon Fiber Composite Materials
Published in Omar Faruk , Jimi Tjong , Mohini Sain, Lightweight and Sustainable Materials for Automotive Applications, 2017
Abdullah Al Mamun, Moyeenuddin Ahmad Sawpan, Mohammad Ali Nikousaleh, Maik Feldmann, Hans-Peter Heim
Plasma surface modification can usually be divided into two categories with opposite effects, depending mainly on the process gas used. The first one mainly ablates the surfaces, and is usually called “plasma treatment,” “plasma surface modification,” “plasma ablation,” or “nonpolymer-forming plasma.” The second one is usually called “plasma polymerization,” “polymer-forming plasma,” or “plasma enhanced chemical vapor deposition.” In the following, “plasma surface modification” is meant to cover both types while “plasma treatment” is used for the first one. If the used gas has high proportions of carbon and hydrogen atoms, double- or triple-bonds in its composition such as methane, ethylene, acetylene, and ethanol, or if they are precursors such as metal-organic (organometallic) gas, the plasma often results in plasma polymerization or PECVD. Here, metal-organic gases are those that contain a metal, particularly compounds in which the metal atom has a direct bond with a carbon atom. Otherwise, the plasma will have a tendency of ablation (plasma treatment). These techniques have been studied for adhesion improvement of carbon fibers [30].
Principles of Friction and Lubrication
Published in Yoshito Ikada, Yoshikimi Uyama, Lubricating Polymer Surfaces, 1998
Yoshito Ikada, Yoshikimi Uyama
Since glow discharge is performed under reduced pressure, not only is the so-called plasma treatment of substrate polymer surfaces possible, but so is the direct deposit of the organic layer onto the surfaces by introducing various gases. The formation of polymeric materials in the plasma environment is termed plasma polymerization. This polymerization reaction proceeds through a more complicated mechanism than the plasma treatment. In most cases, polymers are deposited in a thin film layer onto the substrate materials by plasma polymerization of monomer under glow discharge. The deposited polymers are highly cross-linked and branched. Yasuda et al. [10] attempted polymer deposition by plasma to modify the surface properties of contact lenses. A thin layer of plasma polymer from acetylene/ H2O/N2 was deposited to PMMA contact lenses to a thickness of roughly 20nm. Generally, plasma polymerization is not commonly utilized for surface modification to give hydrophilicity.
Fabrication of cationic polymer surface through plasma polymerization and layer-by-layer assembly
Published in Materials and Manufacturing Processes, 2020
Rui Chen, Changgui Shi, Yanhai Xi, Peng Zhao, Hailong He
Surface modification is an effective way in developing biomaterials because the surface can be selectively modified and the appropriate bulk mechanical and biological properties are retained. In the past 2 decades, plasma polymerization and layer-by-layer (LbL) self-assembly have been widely used for the surface modification of various substrates, such as polypropylene (PP) meshes, hyaluronan/chitosan nanofilms, poly(lactide-co-glycolide) films and titanium alloys.[18] Functional groups can be introduced on the substrate surface with the use of appropriate plasma sources, allowing for subsequent covalent immobilization. In addition, the thickness of polymer coatings on substrates can be tuned through adjusting plasma polymerization conditions. LbL self-assembly technique is a simple, versatile and effective tool to construct multilayered structures on different materials ranging from solid substrate, scaffolds, micro- or nano-particles. Both plasma polymerization and LbL self-assembly techniques have allowed the biomedical applications of a larger number of materials.
Robust hydrophobic coating on glass surface by an atmospheric-pressure plasma jet for plasma-polymerisation of hexamethyldisiloxane conjugated with (3-aminopropyl) triethoxysilane
Published in Surface Engineering, 2019
Md. Mokter Hossain, Quang Hung Trinh, Duc Ba Nguyen, M. S. P. Sudhakaran, Young Sun Mok
Nonthermal plasma (NTP) treatment at atmospheric pressure has been a warm research topic in recent years for making hydrophobic surface of various materials [1–7]. The hydrophobic surface can be used for various purposes such as self-cleaning windows, anti-icing, out-door textiles, self-cleaning of antennas, ultra-dry surface applications, protection of circuits and grids, medical devices, and other optical apparatuses [8–12]. Basically, the thin films deposited by plasma polymerisation are pinhole free, have good adhesion, and have better mechanical and chemical stabilities. To get hydrophobic characteristics the surface requires nano- to micro-scale roughness. Both the surface roughness and the surface chemistry affect the hydrophobicity [2]. Up to now, several methods have been proposed to generate surface roughness, including plasma treatment, sol–gel deposition, anodisation, electrodeposition, chemical treatment, hot-water immersion, and lithography [12–17]. A surface having water contact angle (WCA) from 90° to 150° is known as hydrophobic, and the surface more than 150° is known as super hydrophobic due to its excellent self-cleaning ability.
Plasma treatment of polyethersulfone membrane for benzene removal from water by air gap membrane distillation
Published in Environmental Technology, 2018
Sara Pedram, Hamid Reza Mortaheb, Farzaneh Arefi-Khonsari
In recent years, plasma surface modification has been reported as an important technique to modify the surface wettability of the membrane without affecting the bulk properties. Plasma polymerization is defined as a process in which active particles resulting from the decomposition of low molecular weight organic monomers under plasma influence are recombined to form entirely new higher molecular weight products. Compared to the conventional polymerization which requires specific monomers, plasma polymerization can start from a wide range of organic compounds including saturated hydrocarbons, offering a large variety of possible surface modifications [27,28]. In addition, high chemical [29], mechanical [30], and thermal stabilities [31] along with excellent adhesion of the coating on almost all substrates [32] make this method to be recognized as a unique process.