Improvements of surface functionality of cotton fibers by atmospheric plasma treatment

This study aims to investigate the viability of atmospheric plasma treatment over raw cotton fabric surfaces as an alternative method for superseding the wet textile pre-treatment processes. For this purpose, the fabric samples were treated with air plasma and argon atmospheric plasma. Thereafter, the hydrophilicity and the wickability of plasma treated samples increased, and also the contact angles decreased significantly. Chemical changes were analyzed by FTIR-ATR and XPS. Morphological changes were observed by SEM. The results were inspected for assessing to what extent the replacement might be achieved by inducing this surface modification method.     

Antistatic effect of atmospheric pressure glow discharge cold plasma treatment on textile substrates

Hydrophobic synthetic textile substrates, nylon and polyester fabrics, were continuously treated in an atmospheric-pressure-glow-discharge-cold-plasma reactor using He and air. The samples were evaluated for antistatic properties by measuring the static charge build-up and half charge decay time. The 60 sec air-plasma treated nylon fabric produced only 1.53 kV of charge and showed a significantly smaller half decay time of 0.63 sec compared to static voltage of 2.76 kV and a half decay time of 8.9 sec in the untreated nylon fabric. In comparison, the He plasma treated nylon fabrics showed relatively less improvement by producing static charge built-up of 2.12 kV and half charge decay time of 1.1 sec. Similar improvements were obtained for polyester (PET) fabrics as well. The treated samples showed good antistatic properties even after five laundry wash cycles. The surface characteristics of the samples were investigated using SEM, AFM, and ATR-FTIR. The results revealed that the improvement on antistatic properties are attributable to increase in the surface energy of the fabrics due to the formation of hydrophilic groups and increase in the surface area due to the formation of nano-sized horizontal and vertical channels on the fibre surface. The study suggests that plasma treatment may be used for imparting effective antistatic finish on otherwise hydrophobic substrates.     

The effects of humidity on the surface modification of wool fabric through atmospheric pressure plasma jet

Current research was carried out on hydrophilic wool fibers at three different humidity conditions through atmospheric pressure plasma jet (APPJ). Samples were taken to evaluate surface microscopic morphology, surface roughness, directional friction effect (DFE), and surface chemical composition. The scanning electron microscope (SEM) and fiber friction coefficient test (FFT) results show that wetting pretreatment has significant effect on surface etching and DFE, but very limited effect on surface roughness. Allwörden reaction and X-ray photoelectron spectroscopy (XPS) results reveal that extra moisture changes C, O, N, S contents and their related characteristic functional groups, therefore increases etching degree on wool fiber surface scales. It was concluded that APPJ treatment is effective in processing wool fiber with high moisture contents.     

Surface modification and aging effect of polysulfonamide yarns treated by atmospheric pressure plasma

The effect of atmospheric pressure plasma treatment on wettability and dyeability of polysulfonamide (PSA) yarns and aging behavior were investigated. The helium and helium/oxygen plasma-treated PSA yarns were stored for different time varying from 10 to 60 days at the condition of 25 °C and 65 % relative humidity. The water absorption time and K/S value were used to determine the wettability and dyeability of polysulfonamide yarns before and after plasma treatment. The changes in surface morphology and chemical composition were analyzed by Scanning Electron Microscope (SEM) and X-ray Photoelectron Spectroscopy (XPS). The plasma treatments resulted in the decrease in water absorption time and the increase in K/S value, especially for the helium/oxygen plasma-treated PSA yarns dyed with cationic dyestuff. SEM observation confirmed that the PSA fiber surface was roughed and XPS analysis showed that the polar groups on PSA fiber surface increased after the plasma treatments. As plasma treatment time increased and oxygen gas was added, a greater degree of etching was achieved and more polar groups such as hydroxyl and carboxyl groups produced on PSA fiber surface, contributing to a better wettability and thus a better dyeability of the yarns. Almost no apparent aging effect was observed within 10 days. And then with the increasing storage time, the water absorption time and K/S value firstly quickly and then slowly increased and decreased. However, after 30 days, almost no aging effect was observed. The atmospheric pressure plasma treatment had no obviously influence on tensile strength of PSA yarns.     

Effect of the atmospheric plasma treatment parameters on surface and mechanical properties of jute fabric

Plasma treatment is a kind of environmentally friendly surface modification technology, which has been widely used to modify various materials in many industries. Plasma treatment improves the fiber-matrix adhesion largely by roughening the surface of fibers to increase mechanical interlocking between the fiber and the matrix. For this aim, the effect of atmospheric air plasma treatment on jute fabrics has been discussed in this study. The plasma treatment has been employed at different powers and time intervals. The effects of plasma treatment on fiber properties were revealed by wickability, surface roughness, fiber tensile test and pull-out tests. The effect of plasma treatment on functional groups of jute fibers was observed by attenuated total reflectance fourier transform infrared spectroscopy (ATR-FTIR). Scanning electron microscopy (SEM) images showed the etching effect of plasma treatment on the surface. It can be concluded that plasma treatment is an effective method to improve the surface and mechanical properties of jute fabrics to be used for composite materials.     

The application of gas plasma technologies in surface modification of aramid fiber

Gas plasma technologies have been utilized to improve the surface properties of fibers in many applications from textiles to fiber-reinforced composites since the 1960s. This review discusses the feasibility and characteristics of gas plasma technologies applied to aramid fiber. The influence of various plasma treatments on the chemical and mechanical properties of aramid fibers as well as fiber-reinforced composites is described. The moisture regain is emphasized to achieve good bonding between aramid fibers and polymer matrix and to enhance the surface modification of aramid fiber and mechanical properties of the composites. More sophisticated technologies such as plasma-initiated graft polymerization are also discussed to highlight very recent developments.     

A study on chitosan modification of polyester fabrics by atmospheric pressure plasma and its antibacterial effects

Chitosan is a natural nontoxic biopolymer used widely in various fields due to the antimicrobial activities. In this study, the properties of polyester fabrics grafted with chitosan oligomers/polymers after being activated by atmospheric pressure plasmas were evaluated. The antibacterial effect was most evident when the surface of fabrics was activated by atmospheric pressure plasma for 60 to 120 seconds and grafted with chitosan oligomers. The modified fabrics also exhibited good biocompatibility. This process can be applied to a large area and used to produce antibacterial polymer fibers.     

Atmospheric plasma treatment of polypropylene fabric for improved dyeability with insoluble textile dyestuff

Polypropylene (PP) fabrics were activated by an atmospheric pressure, dielectric barrier discharge to optimize the effects of some discharge parameters on the dyeability of PP fabrics. Air and argon plasmas were used to modify the surfaces of the fabrics, and the effects on dyeability were investigated when the treated fabrics were dyed by leuco and pigment forms of vat dyestuffs. Surface properties of plasma-treated samples were characterized by Fourier transform infrared spectroscopy (FTIR-ATR), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). Vat-dyed samples showed a significant increase in color strength when PP fabrics were pretreated with atmospheric pressure plasmas of either argon or air.     

Improving certain properties of wool fibers by applying chitosan nanoparticles and atmospheric plasma treatment

The nanochitosan particles were prepared by ionic gelation method using sodium tripolyphosphate (TPP) as anionic chemical agent. Structural and morphological properties of the nanoparticles were characterized by dynamic light scattering (DLS), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FTIR) analyses. The results showed that nanoparticles were spherical with a diameter range of 17-105 nm. After nanochitosan synthesis, the effects of chitosan and nanochitosan concentrations on the dyeability, fastness properties, shrink-proofing, tensile strengths, and surface friction coefficients of untreated and plasma treated wool fabrics were investigated. The studies revealed that nanochitosan treated wool fabric possesses better dyeing and shrink-proofing properties in comparison with conventional chitosan treated fabrics.     

Helium/oxygen atmospheric pressure plasma treatment on poly(ethylene terephthalate) and poly(trimethylene terephthalate) knitted fabrics: Comparison of low-stress mechanical/surface chemical properties

Helium-oxygen plasma treatments were conducted to modify poly(trimethylene terephthalate)(PTT) and poly(ethylene terephthalate) (PET) warp knitted fabrics under atmospheric pressure. Lubricant and contamination removals by plasma etching effect were examined by weight loss (%) measurements and scanning electron microscopy (SEM) analysis. Surface oxidation by plasma treatments was revealed by x-ray photoelectron spectroscopy (XPS) analyses, resulting in formation of hydrophilic groups and moisture regain (%) enhancement. Low-stress mechanical properties (evaluated by Kawabata evaluation system) and bulk properties (air permeability and bust strength) were enhanced by plasma treatment. Increasing interfiber and interyarn frictions might play important roles in enhancing surface property changes by plasma etching effect, and then changing low-stress mechanical properties and bulk properties for both fabrics.