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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
Plasma activation is a surface change by the reactive molecules formed in the plasma. The combination will result from the interactive molecules to integrate radical sites on the substrate surface for a depth up to 10 nm. These sites will interact with other existing radicals, and combine different functional groups according to the gas used. The new reactive sites influence the surface properties significantly like wetting ability and the surface free energy that support the interactions of physical materials and cells. In most cases, the follow–up increases in water resistance to improve the performance of textile. In many applications like the surface of the heart valves or internal shields for needles or industrial stents, the cells and proteins adhesion is strongly desirable leading to a blockage and medical devices vital early failure. Instead of using the usual feed gas to the plasma processing (noble gases, nitrogen, dry air, oxygen, etc.), the use of fluorinated gases such as CF4 that create surfaces possess hydrophobic nature with high water contact angles reaches to 150 degree or more. These hydrophobic interfaces prohibit cells and proteins from sticking strongly and thus ensuring the best performance of the implant substrate (Geyter et al., 2008; Mattioli et al., 2012; Jacobs et al., 2013). Sure, there are other methods rather than plasma activation that can generate new active sites on the substrate surface; however, plasma is nonmetaphorical, nonchemical, and it ensures that the most sensitive structures are preserved.
Surface modification of high density polyethylene and polycarbonate by atmospheric pressure cold argon/oxygen plasma jet
Published in B. Raneesh, Nandakumar Kalarikkal, Jemy James, Anju K. Nair, Plasma and Fusion Science, 2018
R. Shrestha, J. P. Gurung, A. Shrestha, D. P. Subedi
Polymers surfaces generally have low surface energy and high chemical inertness, and so they usually have poor wetting and adhesion properties [1]. Hence, surface modification of polymeric materials plays an important role to improve surface properties such as wetting and adhesion for coatings, inking and printing processes, biomaterials, and certain types of composites materials. Therefore, various modification techniques have been used to overcome such type of problems. This includes the use of the UV irradiation, laser, chemical treatment flame, grafting, as well as plasma treatment [2]. One of the most interesting methods used to increase their surface energy and improve adhesive properties is plasma activation of their surfaces. Plasma treatment for activating polymers provides uniformity on the surface of the polymer. Plasma used for these applications, although not fully ionized, are composed of ions, free electrons, photons, neutral atoms, and molecules in ground and excited electronic states. Each of these components has the potentials of interaction with surfaces with which they come in contact. The plasma process results in a physical and/ or chemical modification of the first few molecular layers of the surface, while maintaining the properties of the bulk phase. The depth of modification with plasma treatments is generally less than 10 nm [3].
Carbon Nanotubes: Preparation and Surface Modification for Multifunctional Applications
Published in Vineet Kumar, Praveen Guleria, Nandita Dasgupta, Shivendu Ranjan, Functionalized Nanomaterials I, 2020
Jingyao Sun, Jing Zhu, Merideth A. Cooper, Daming Wu, Zhaogang Yang
Plasma activation is a commonly used method for surface modification via plasma processing. There are many kinds of plasma that can be used in a plasma activation processes. Atmospheric pressure plasmas, including corona discharge, arc discharge, dielectric barrier discharge, etc., have found the most application because no expensive vacuum equipment or wet chemistry situations were needed during the modification process. Many kinds of industrial gases, such as oxygen, hydrogen, and nitrogen can be applied for CNT modification at atmospheric pressure (Kalita et al., 2009; Okpalugo et al., 2005).
Modification of the elemental composition of iron(III) oxide as an asymmetric supercapacitor anode: A minireview
Published in Instrumentation Science & Technology, 2020
The specific surface area is increased by synthesizing Fe2O3 on a carbon cloth, and surface modification is performed by plasma activation to form nanorods. Plasma activation generates atomic vacancies (defects), which can provide more active sites for electrochemical reactions. The results show that the PH3 plasma activation can effectively adjust the active specific surface area, electrical conductivity, and defect concentration, thereby greatly improving performance. Specifically, PH3 plasma-activated Fe2O3 (Fe2O3-P) was shown to provide a high area capacitance of 340 mF cm−2 at a speed of 1 mA cm−2 in 1 M Na2SO4 compared to the original Fe2O3 with a value of 66 mF cm−2. Figure 5 shows the complete process of preparing Fe2O3-P from the FeOOH precursor.
Composite surface pre-treatments: Improvement on adhesion mechanisms and mechanical performance of metal–composite friction spot joints with additional film interlayer
Published in The Journal of Adhesion, 2018
Natália Manente André, Seyed M. Goushegir, Nico Scharnagl, Jorge F. dos Santos, Leonardo B. Canto, Sergio T. Amancio-Filho
Energetic surface treatments, such as plasma activation, are other types of treatments, which enhance the adhesion mainly due to the increase of surface energy. The plasma oxidizes the polymer surface, leading to the removal of organic contaminants and introduction of polar functional groups. Thus, more reactive and wettable surfaces can be created.[23] Surfaces in contact with the plasma are bombarded by high energetic species. During the collisions, the energy of the species is transferred from the plasma to the solid surface and dissipated through several physical and chemical processes, resulting in a higher energetic modified surface. These superficial changes can achieve depths from several hundred angstroms to 10 µm without changing any bulk properties of the material.[24] Kim et al.[25] demonstrated the effect of plasma treatment on the adhesive bonding of a carbon/epoxy composite. The authors showed a decrease in contact angle while the surface energy increased, indicating a more effective wetting of the surface and better adhesion between composite and adhesive. Iqbal et al.[26] investigated the surface modification of high-performance polymers, such as CF– and GF-PPS and PEEK, by plasma treatment and its influence on the adhesive bonding of these materials. It was demonstrated that the strength of adhesively bonded joints improved from 6 to 22 MPa due to the formation of functional groups after plasma activation.