Effect Of Low Temperature Plasma Treatment Research Articles

An analysis of ramie fiber (Boehmeria nivea L. Gaud) treated with low temperature plasma using a mathematical model

This research aims to characterize low-temperature plasma-treated ramie fibers (Boehmeria nivea L. Gaud), create a mathematical model, and analyze them using image processing. The effects of low-temperature plasma treatment on ramie fibers were investigated using 30 kV output powers, 4-min treatment times, and a 4 cm electrode distance. SEM and FT-IR spectroscopy were used to investigate various aspects of the ramie fiber’s chemical properties and surface topography. This study used a statistical approach to analyze the SEM images. The statistical analysis was used to investigate the surface roughness using the SEM images. FT-IR analysis discovered that fibers that were exposed for four minutes differed from untreated fibers. According to the findings, plasma treatment caused: (1) ramie fiber became more hydrophilic, as indicated by the presence of hydrophilic functional groups such as hydroxyl (O–H), carboxyl (O–C), and carbonyl (C=O) in FT-IR with a deeper T%, (2) ramie fiber mass reduction was accompanied by an increase in surface roughness via SEM testing and image processing, and (3) plasma-treated fiber had a coefficient of mass variation (CV) of 0.7211 higher than untreated fiber. The novelty of this study is the use of image processing in SEM to observe surface roughness and its relationship to the chemical structure of ramie fibers observed with FT-IR. Another novelty of this research is the mathematical model of the interaction of plasma species with the ramie fibers on the plane electrode for the first time.

Effect of low-temperature plasma treatment on electrophysical and physical-mechanical properties of CVD coatings of carbide plates

The results of the study of the influence of regime parameters of the process of low-temperature plasma treatment on the electrical and physical-mechanical properties of CVD coatings of replaceable multifaceted hard-alloy plates are presented.

Design of Non-Thermal Plasma Alfalfa Seed Vigor Enhancement Device and Study of Treatment Effect

Highlights An effective seed treatment method is provided. Three generations of field growth trials were conducted. We Investigated the effects of low-temperature plasma treatment on the biological characters and yield components. Abstract. An atmospheric pressure, low-temperature dielectric barrier discharge (DBD) plasma seed treatment device was developed for plasma seed treatment. The device worked continuously on alfalfa seeds and evenly distributed the seeds in a plasma discharge range. The processing time, voltage amplitude, and frequency were adjustable. The device was used to study the effect of DBD plasma treatment at different voltages and times on alfalfa seed germination using untreated alfalfa seeds as the control (CK). The results showed that the DBD plasma treatment of alfalfa seeds promoted seed germination and seedling growth, and the optimal discharge conditions were a discharge voltage of 11 kV and a discharge time of 40 s. Compared with CK, the germination potential and germination rate increased by 12.49% and 18.08%, respectively. After treatment using the optimal discharge time, the germination potential, germination rate, dry weight, and seedling height increased by 9.9%, 16.1%, 15%, and 32.9%, respectively, compared with CK. The Scanning Electron Microscope images of the seed epidermis treated with 11 kV and 40 s plasma showed that the surface of alfalfa seeds was etched. Different doses of discharge radiation had different effects on physiological processes in seeds, and their sensitivity to plasma discharge was different. In a certain range, the germination rate, germination potential, fresh weight, dry weight, root length, and seedling height of alfalfa seeds improved to different degrees under different discharge voltages and times. Plasma has a good application prospect for improving the growth of alfalfa seeds. Keywords: Alfalfa, Dielectric barrier discharge plasma, Germination, Seed treatment device, Seedling growth.

Effect of Low-Temperature Plasma Treatment on The Properties of a Complex Wool-Containing Material

The article investigates a layer of felt in a complex material, which we intend as rehabilitation footwear element. The complex material consists of layers of rubber and felt, connected with polyurethane adhesive, and we design it for the manufacture of shoe-product sole. The layer of felt inside is in contact with the foot and serves as an insole. The felt was treated with low-temperature plasma (LTP) from the inside of the complex material. It was experimentally obtained the wettability index: for the complex material, containing a treated layer of felt, and a control untreated felt. The research obtained an increase in the hydrophilicity of the LTP-treated felt, which is explained by degreasing the surface, an increase in the porosity of the non-woven material «felt», as well as structural changes in the wool fiber due to plasma treatment. Plasma treatment of woolen felt layer can be recommended to increase the hydrophilicity of the surface and impart antibacterial properties to the inner («insole») surface of the complex material by applying infusions of medicinal plants, etc.

Effect of Low-Temperature Plasma Treatment on Starch-Based Biochar and Its Reinforcement for Three-Dimensional Printed Polypropylene Biocomposites.

Uniform dispersion and high interfacial adhesion are two of the most difficult components of creating an ideally reinforced polymer composite. One of the solutions could be surface engineering of reinforcing filler materials utilizing innovative technologies. Low-temperature plasma treatments in the presence of sulfur hexafluoride (SF6) gas are proposed as a sustainable alternative to modify the surface properties of biochar carbon synthesized from sustainable starch-based packaging waste via a high-temperature/pressure pyrolysis reaction in the current study. X-ray photoelectron spectroscopy tests revealed that plasma treatments were effective in the fluorination of biochar carbon like wet chemical methods. By delivering fluorine-related functionalities only on the surface of the carbon, plasma treatments were efficient in changing the surface properties of biochar carbon while keeping the carbon's beneficial bulk properties intact, which is unique to this method. The modified biochar was effectively utilized to reinforce polypropylene. Mechanical properties like tensile strength improved by 91% when compared to neat polymers and 31% when compared to untreated biochar-reinforced polymers at 0.75 wt % loadings. Elongation at break increased from 12.7 to 38.78, showing an impressive 216% increase due to effective reinforcement by plasma functionalization. The decomposition onset temperature and maximum rate of decomposition temperature increased by 60 and 49 °C, respectively, when compared to neat polymers. Plasma-modified biochar-reinforced three-dimensional printed samples have shown promise to be utilized for the development of composite parts using additive manufacturing methods.

Current Advancements in the Molecular Mechanism of Plasma Treatment for Seed Germination and Plant Growth.

Low-temperature atmospheric pressure plasma has been used in various fields such as plasma medicine, agriculture, food safety and storage, and food manufacturing. In the field of plasma agriculture, plasma treatment improves seed germination, plant growth, and resistance to abiotic and biotic stresses, allows pesticide removal, and enhances biomass and yield. Currently, the complex molecular mechanisms of plasma treatment in plasma agriculture are fully unexplored, especially those related to seed germination and plant growth. Therefore, in this review, we have summarized the current progress in the application of the plasma treatment technique in plants, including plasma treatment methods, physical and chemical effects, and the molecular mechanism underlying the effects of low-temperature plasma treatment. Additionally, we have discussed the interactions between plasma and seed germination that occur through seed coat modification, reactive species, seed sterilization, heat, and UV radiation in correlation with molecular phenomena, including transcriptional and epigenetic regulation. This review aims to present the mechanisms underlying the effects of plasma treatment and to discuss the potential applications of plasma as a powerful tool, priming agent, elicitor or inducer, and disinfectant in the future.

Effect of modification of reinforcing fibers on strength properties of microplastic samples

The main properties of high-strength high-modulus fibers are considered. The effect of low-temperature plasma treatment on the breaking load of microplastics has been studied. The maximum load of microplastics has been established.

Effect of Low-Temperature Plasma Treatment and γ Irradiation on the Surface Properties of Thin Films Based on Polylactic Acid

Effect of Low-Temperature Plasma Treatment and γ Irradiation on the Surface Properties of Thin Films Based on Polylactic Acid

Effect of Low-Temperature Plasma Treatment on Surface Modification of Polycaprolactone Pellets and Thermal Properties of Extruded Filaments

Polycaprolactone (PCL) polymer has been surface modified using oxygen low-temperature plasma and melt extruded into single filaments. Oxygen plasma was generated using a radiofrequency source with power of 150 W. The PCL polymer samples were treated with plasma for various durations of 5 min, 10 min, and 20 min. Water contact angle measurements were carried out to assess the wettability, revealing that the treatments reduced the contact angle by up to 11°. Changes in the chemical bonding and surface compositions were characterized by using x-ray photoelectron spectroscopy and Fourier-transform infrared spectroscopy, revealing a high concentration of oxygen functionalities on the surface. Crystallinity changes were studied by using x-ray diffraction analysis. The surface morphology of the polymer was investigated using field-emission scanning electron microscopy. The thermal degradation and melting behavior was studied using thermogravimetric analysis and differential scanning calorimetry, respectively.

Adsorption Behavior of Fibronectin to Titanium and Zirconia : Effect of Low-temperature Plasma Treatment

Adsorption Behavior of Fibronectin to Titanium and Zirconia : Effect of Low-temperature Plasma Treatment

Effects of low-temperature plasma treatment on pulmonary function in children with obstructive sleep apnea-hypopnea syndrome.

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is a common sleep-related respiratory disease. Despite reports of low-temperature plasma radiofrequency ablation of tonsils and adenoids for the treatment of OSAHS, the effects on lung function and quality of life are unclear. This study aims to explore the effects of low-temperature plasma treatment on pulmonary function in children with OSAHS. A total of 110 children with OSAHS were included in this prospective study. Low-temperature plasma radiofrequency treatment and routine surgical treatment were performed in group A and group B, respectively. Maximal voluntary ventilation (MVV), forced vital capacity (FVC), and total lung capacity (TLC) were measured. OSA-18 survey was used to evaluate the quality of life 1 year after operation. Group A had significantly higher effective treatment rate (P < 0.05) and lower operative period, bleeding volume, visual analog score, pseudomembrane detachment time, and time required to feed after operation than group B (all P < 0.001). There were no significant difference in the incidence of postoperative complications between the groups and MVV, FVC, and TLC between the groups before and after operation (all P > 0.05), and the above indexes in both groups were significantly increased after operation (all P < 0.05). OSA-18 scores in group A were significantly lower than group B after operation (P < 0.001). Low-temperature plasma technique performed in OSAHS children has a good clinical effect, which can reduce the operation time, intraoperative blood loss, postoperative pain, pseudomembrane detachment time, hospitalization time, and improve pulmonary function and quality of life.

Effects of low-temperature plasma treatment on wettability of glass surface: Molecular dynamic simulation and experimental study

The improvement of wettability of glass surface plays a vital role in the bonding between glass and other materials. Low-temperature plasma treatment can improve the wettability of glass surface, but the micro-mechanism needs further study. In this paper, the glass surface was treated by low-temperature plasma, and the wettability of the treated surface was studied by experiment and molecular dynamics (MD) simulation. The results show that the relative content of oxygen of the glass surface increases while that of carbon impurity decreases after low-temperature plasma treatment. After low-temperature plasma treatment, the wettability of glass surface is improved obviously while the surface morphology is almost unchanged. MD simulation results show that the active groups are more easily adsorbed on the glass surface in a free state and interact strongly with water. Among them, the interaction between the hydroxylated glass surface and water droplets is the strongest, so the wettability of glass surface is obviously improved. The number of chemical bonds between the glass surface and water increases after low-temperature plasma treatment and the number of chemical bonds in the hydroxylated glass system increases the most. Therefore, the interfacial bonding is enhanced, and the wettability of the glass surface is improved. The simulation results are in agreement with the experimental ones. The above research provides a theoretical basis for improving the strength of glass bonded joints.

Low-temperature plasma treatment of carbon fibre/epoxy resin composite

ABSTRACTTo gain insight into bonded repairs, which are commonly applied to damaged composites, we herein investigate the effects of low-temperature plasma treatment on the surface properties of a carbon fibre/epoxy resin composite, revealing that this treatment enhances the bonding strength between the patch and damaged surface. Moreover, we probe the water contact angle, chemical composition, tensile-shear strength, and morphology of composite surfaces, showing that under optimal conditions, plasma treatment decreases the water contact angle from 78° to 35.5°, increases the surface energy by a factor of ∼2.3, and induces the formation of surface-bound oxygen-containing groups, increasing the O/C ratio by ∼70%. Compared to that of the untreated composite, the tensile-shear strength of the plasma-treated composite initially increases and subsequently decreases with increasing treatment time, with the maximum increase reaching 117%. Finally, the obtained experimental data allow the above-mentioned plasma treatment to be modelled by a four-stage process.

Effect of low-temperature plasma treatment of electrospun polycaprolactone fibrous scaffolds on calcium carbonate mineralisation.

This article reports on a study of the mineralisation behaviour of CaCO3 deposited on electrospun poly(ε-caprolactone) (PCL) scaffolds preliminarily treated with low-temperature plasma. This work was aimed at developing an approach that improves the wettability and permeability of PCL scaffolds in order to obtain a superior composite coated with highly porous CaCO3, which is a prerequisite for biomedical scaffolds used for drug delivery. Since PCL is a synthetic polymer that lacks functional groups, plasma processing of PCL scaffolds in O2, NH3, and Ar atmospheres enables introduction of highly reactive chemical groups, which influence the interaction between organic and inorganic phases and govern the nucleation, crystal growth, particle morphology, and phase composition of the CaCO3 coating. Our studies showed that the plasma treatment induced the formation of O- and N-containing polar functional groups on the scaffold surface, which caused an increase in the PCL surface hydrophilicity. Mineralisation of the PCL scaffolds was performed by inducing precipitation of CaCO3 particles on the surface of polymer fibres from a mixture of CaCl2- and Na2CO3-saturated solutions. The presence of highly porous vaterite and nonporous calcite crystal phases in the obtained coating was established. Our findings confirmed that preferential growth of the vaterite phase occurred in the O2-plasma-treated PCL scaffold and that the coating formed on this scaffold was smoother and more homogenous than those formed on the untreated PCL scaffold and the Ar- and NH3-plasma-treated PCL scaffolds. A more detailed three-dimensional assessment of the penetration depth of CaCO3 into the PCL scaffold was performed by high-resolution micro-computed tomography. The assessment revealed that O2-plasma treatment of the PCL scaffold caused CaCO3 to nucleate and precipitate much deeper inside the porous structure. From our findings, we conclude that O2-plasma treatment is preferable for PCL scaffold surface modification from the viewpoint of use of the PCL/CaCO3 composite as a drug delivery platform for tissue engineering.

The effects of low-temperature plasma treatment on the capillary properties of inorganic fibers

Solving the problem of achieving high adhesion between the components in the polymeric composite material (PCM) based on carbon fibers (CF) and basalt fibers (BF) is proposed to use the radio-frequency (RF) plasma under lower pressure by virtue of efficiency, environmental friendliness and rationality of the method. The paper gives the results of studies of the properties of CF and BF after RF capacitive discharge plasma treatment. The plasma modification modes of carbon and basalt fiber were investigated. The efficiency of treatment tool in surface properties modification of carbon and basalt fibers was found, namely capillary properties of CF and BF were researched. The optimal treatment modes were selected. It was found that the method of plasma modification in the radio-frequency capacitive discharge under the lower pressure contributes enhancing the capillary properties of inorganic fibers, in particular carbon and basalt ones. It shows the tendency to increase of the adhesive properties in PCM, and, consequently, the increase of the physical and mechanical properties of the products.

Effect of Low-Temperature Plasma Treatment on Surface Properties of LDPE Film

Low-density polyethylene (LDPE) film was treated by low-temperature plasma. Scanning electronic microscope, electronic universal testing machine, contact angle/interfacial tension measuring instrument were used to analyze the surface morphology, surface contact angle, bonding strength and performance of LDPE film before and after they were treated by low-temperature plasma. The results show that air ambience is more appropriate than N2, CO2 for treatment. Specifically, plasma treatment in air ambience, under conditions of 44 W (power), 30 s (duration) and 60 Pa (vacuum degree), can decline static contact angle of LDPE film from 101° to 13.5°. The transiency of plasma-treated LDPE film is so obvious that storage time of longer than one hour will result in a contact angle up to 74° and loss of plasma treatment effect (timeliness). Therefore, the reversible plasma-treated LDPE film should be processed immediately.

Low-temperature Plasma - a Prospective Microbicidal Tool

The effects of low-temperature plasma treatment on microorganisms typically related to skin diseases are studied qualitatively by the inhibition of growth and viability assays to evaluate the potential for classifying as a prospective antiseptic agent. A variety of microorganisms enveloping gram- negative and gram-positive bacteria as well as one genus of yeast and fungus each were exposed to plasma in vitro. In a comparative approach, two power supplies, both of which produce high voltage pulses yet at different temporal characteristics, are applied for the growth study. While operation with both devices led to growth inhibition of all microbes, the results indicate a superior antimicrobial efficacy for high voltage pulse lengths in the nanosecond scale. Fluorescence assays reveal the efficacy of nanosecond-pulse driven plasma in reducing germ viability. Furthermore, the technical background for patents related to low-temperature plasma technology in the field of plasma medicine is discussed.

Effect of low-temperature plasma treatment on tailorability and thermal properties of wool fabrics

Dielectric barrier discharge type of plasma reactor was used for the low-temperature plasma (LTP) treatment of the wool fabrics. Air was used as the non-polymerizing gas for the plasma treatment at different time intervals. Low-stress mechanical properties of the treated and untreated wool fabrics were evaluated using Siro-fast technique which revealed that the tensile, bending, compression, shear, dimensional stability and surface properties were altered after the LTP treatment. Other properties such as thermal conductivity, thermal resistance and pilling propensity were also evaluated. The surface topographical changes of the wool fibres after LTP treatment were analysed by scanning electron microscopy. The changes in these properties are supposed to be related closely to the interfibre and interyarn frictional force and increased surface area of the fibres induced by the etching effect of plasma.

Improvement of dye adsorption on synthetic polyester fibers by low temperature plasma pre-treatment

Adsorption of the dyes on the surface of the natural and synthetic polymer fibers, or weaved fabrics is created due to the effect of the intermolecular forces between fiber surface and the dye. Such forces are causing relatively strong bonding interaction between dye dipoles and the stained matrix. In the case of polymer and biopolymer materials the number of the dipoles is directly proportional to the number of polar groups in macromolecular side chains. The latter number of present dipoles is possible to be increased by several physico-chemical methods, e.g. fire treatment, chemical etching by strong acids, UV irradiation, corona discharge or low-temperature plasma treatments etc. In this communication the effect of low-temperature plasma treatment of polyester (PES) weaved fabric on dye adsorption to the surface of the studied substrate is discussed. Obtained increased dye selectivity to the stained matrix results in improved tinctorial strength, better economical effectiveness as well as to the improved ecology of the process.

Fouling and protein adsorption effect of low-temperature plasma treatment of membrane surfaces

Adsorption of proteins and the effect of the chemical nature of membrane surfaces on protein adsorption were investigated using 14C-tagged albumin and several microporous membranes (polyvinilydene fluoride, PVDF; nylon; polypropylene, PP; and polycarbonate, PC). The membrane surfaces were modified by exposing them to low-temperature plasma of several different monomers (n-butane, oxygen, nitrogen alone or as mixtures) in a radiofrequency plasma reactor. Transients in the permeability of albumin solutions through the membranes and changes in flux of distilled water through the membranes before and after adsorption of albumin were used to investigate the role of protein adsorption on membrane fouling. The results show that the extent of adsorption of albumin on hydrophobic membranes was considerably more than that on hydrophilic membranes. The hydrophilic membranes were susceptible to electrostatic interactions and less prone to fouling. A pore-blocking model was successfully used to correlate the loss of water flux through pores of defined geometry.