Environmentally Sustainable Flame Retardant Surface Treatments for Textiles: The Potential of a Novel Atmospheric Plasma/UV Laser Technology

Conventional flame retardant (FR) application processes for textiles involve aqueous processing which is resource intensive in terms of energy and water usage. Recent research using sol-gel and layer-by-layer chemistries, while claimed to be based on more environmentally-sustainable chemistry, still require aqueous media with the continuing problem of water management and drying processes being required. This paper outlines the initial forensic work to characterise commercially produced viscose/flax, cellulosic furnishing fabrics which have had conferred upon them durable flame retardant (FR) treatments using a novel, patented atmospheric plasma/UV excimer laser facility for processing textiles with the formal name - Multiplexed Laser Surface Enhancement (MLSE) system. This system (MTIX Ltd., UK), is claimed to offer the means of directly bonding of flame retardant precursor species to the component fibres introduced either before plasma/UV exposure or into the plasma/UV reaction zone itself, thereby eliminating a number of wet processing cycles. Nine commercial fabrics, pre-impregnated with a semi-durable, proprietary FR finish and subjected to the MLSE process have been analysed for their flame retardant properties before and after a 40 °C 30 min water soak. For one fabric, the pre-impregnated fabric was subjected to a normal heat cure treatment which conferred the same level of durability as the plasma/UV-treated analogue. TGA and LOI were used to further characterise their burning behaviour and the effect of the treatment on surface fibre morphologies were assessed. Scanning electron microscopy indicated that negligible changes had occurred to surface topography of the viscose fibres occurred during plasma/UV excimer processing.

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Surface Modification of Commingled Flax/PP and Flax/PLA Fibres by Silane or Atmospheric Argon Plasma Exposure to Improve Fibre–Matrix Adhesion in Composites

Fibers ◽

10.3390/fib10010002 ◽

2021 ◽

Vol 10 (1) ◽

pp. 2

Author(s):

Wiwat Pornwannachai ◽

A. Richard Horrocks ◽

Baljinder K. Kandola

Keyword(s):

Flame Retardant ◽

Surface Treatments ◽

Atmospheric Plasma ◽

Poly Lactic Acid ◽

Flexural Properties ◽

Plasma Exposure ◽

Sem Images ◽

Matrix Adhesion ◽

Maximum Improvement ◽

Fibre Matrix

Challenges faced by natural fibre-reinforced composites include poor compatibility between hydrophilic fibres such as flax and hydrophobic polymeric matrices such as polypropylene (PP) or poly(lactic acid) (PLA), and their inherent flammability. The former promotes weak interfacial adhesion between fibre and matrix, which may be further compromised by the addition of a flame retardant. This paper investigates the effect that the added flame retardant (FR), guanylurea methylphosphonate (GUP) and selected surface treatments of commingled flax and either PP or PLA fabrics have on the fibre/matrix interfacial cohesive forces in derived composites. Surface treatments included silanisation and atmospheric plasma flame exposure undertaken both individually and in sequence. 1-, 2- and 8-layered composite laminates were examined for their tensile, peeling and flexural properties, respectively, all of which yield measures of fibre-matrix cohesion. For FR-treated Flax/PP composites, maximum improvement was obtained with the combination of silane (using vinyltriethoxysilane) and plasma (150 W) treatments, with the highest peeling strength and flexural properties. However, for FR-treated Flax/PLA composites, maximum improvement in both properties occurred following 150 W plasma exposure only. The improvements in physical properties were matched by increased fibre-matrix adhesion as shown in SEM images of fractured laminates in which fibre-pullout had been eliminated.

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Evaluation of the Effect of Ultraviolet Light Excitation during Characterization of Silicon Carbide Epitaxial Layers

Materials Science Forum ◽

10.4028/www.scientific.net/msf.924.261 ◽

2018 ◽

Vol 924 ◽

pp. 261-264

Author(s):

Hrishikesh Das ◽

Swapna Sunkari ◽

Oener Akdik ◽

Andrei Konstantinov ◽

Krister Gumaelius ◽

...

Keyword(s):

Silicon Carbide ◽

Ultraviolet Light ◽

Defect Detection ◽

Uv Light ◽

Surface Treatments ◽

Uv Laser ◽

Original State ◽

Optimal Surface ◽

Light Excitation

The scanning of Silicon Carbide (SiC) epitaxy wafers for defects by ultraviolet (UV) laser or lamps is widely prevalent. In this work, we document the effects of UV light excitation on the SiC epitaxy material. An increase in background photoluminescence (PL) is observed after repeated scans. The effect of this increase on defect detection is shown. Optimal surface treatments to recover the material back to the original state are demonstrated. Further, some surface treatments are proposed which reduce the effect of the UV light excitation and prevent to a large extent the rise in background PL.

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Solid state UV-laser technology for the manufacture of high performance organic modules

1998 Proceedings. 48th Electronic Components and Technology Conference (Cat. No.98CH36206) ◽

10.1109/ectc.1998.678802 ◽

2002 ◽

Cited By ~ 6

Author(s):

D.B. Noddin ◽

E. Swenson ◽

Yunlong Sun

Keyword(s):

Solid State ◽

High Performance ◽

Uv Laser ◽

Laser Technology

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Effect of plasma grafting with Hexamethyldisiloxane on comfort and flame resistance of cotton fabric

Industria Textila ◽

10.35530/it.072.02.1842 ◽

2021 ◽

Vol 72 (02) ◽

pp. 225-230

Author(s):

RIADH ZOUAR ◽

SONDES GARGOUBI ◽

Emilia Visileanu

Keyword(s):

Flame Retardant ◽

Cotton Fabric ◽

Cotton Fabrics ◽

Atmospheric Plasma ◽

Clothing Industry ◽

Plasma Technology ◽

Flame Resistance ◽

Before And After ◽

Plasma Grafting ◽

The Media

We investigated the potential of atmospheric plasma technology to enhance the properties of textile material against flame propagation before and after washing. The effects of this treatment on the rigidification of the media were also determined using draping and bending stiffness tests. We showed that deposing Silicone molecules on cotton fabrics leads to flame retardant cotton with a conservation of the whole structure after burning. Moreover, washing of the sample evidenced high permanency of the thin grafted coating against chemical domestic washing detergent. Nevertheless, comfort properties of the textile decrease, which limits the applications of the plasma eco-friendly technology in the clothing industry.

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Processing technology and experimental analysis of gas-assisted laser cut micro thin wood

BioResources ◽

10.15376/biores.15.3.5366-5378 ◽

2020 ◽

Vol 15 (3) ◽

pp. 5366-5378

Author(s):

Qingwei Liu ◽

Chunmei Yang ◽

Bo Xue ◽

Qian Miao ◽

Jiuqing Liu

Keyword(s):

Flame Retardant ◽

Surface Quality ◽

Laser Cutting ◽

Gas Flow ◽

Processing Parameters ◽

Laser Technology ◽

Gas Processing ◽

Surface Burning ◽

Direct Cutting

Unsupported combustion nitrogen (N2) and flame-retardant helium (He) were used to facilitate laser-cutting of cherry wood, and the effects of process parameters, gas flow, and gas reactivity on the surface quality of thin wood were studied. Using identical processing parameters, the cherry wood was laser-cut with and without the added gases. Through comparing the cutting width, heat affected zone (HAZ), and surface burning conditions under different gas-assistance conditions, the influence of the added gases on the gasification and combustion of cherry wood was analyzed. When N2 gas was used, the cutting width was less than that of laser direct cutting, but the surface of the burning area did not remarkably improve. Under the same conditions, when He gas was added, the burning areas on both sides of the kerf were remarkably reduced and the consistency of kerf was good. This indicated that He gas had good oxygen isolation and flame-retardant effects. The surface of the kerf was observed with a scanning electron microscope, and addition of He gas remarkably improved the burning that occurred when cutting kerf. This study combined gas processing and laser technology, and it provided technical references for reducing post treatment improving the surface quality of laser-processed wood.

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Adhesion Improvement of Thermoplastics-Based Composites by Atmospheric Plasma and UV Treatments

Applied Composite Materials ◽

10.1007/s10443-020-09854-y ◽

2021 ◽

Author(s):

Gennaro Scarselli ◽

Dong Quan ◽

Neal Murphy ◽

Brian Deegan ◽

Denis Dowling ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Adhesive Bonding ◽

Contact Angles ◽

Lap Joints ◽

Surface Treatments ◽

Polyphenylene Sulfide ◽

Atmospheric Plasma ◽

Thermoplastic Composites ◽

Lap Shear ◽

Carbon Fibre Composites

AbstractThe present work is concerned with adhesive bonding of thermoplastic composites used in general aerospace applications, including polyphenylene sulfide (PPS), polyetherimide (PEI) and polyetheretherketone (PEEK) carbon fibre composites. Three different surface treatments have been applied to the PEEK, PPS and PEI-based composites in order to enhance the adhesion: atmospheric plasma, ultraviolet radiation (UV) and isopropanol wiping as a control. Water contact angles and free surface energies were measured following the standard experimental procedure based on the employment of three different liquid droplets. Infrared spectroscopy and X-ray photoelectron spectroscopy (XPS) were subsequently performed to characterize the surface chemistry of the samples after treatment. The single lap joints were manufactured and bonded by an Aerospace grade epoxy-based film adhesive originally developed for use on metals but with the ability to bond treated thermoplastics to good strength (supplied by Henkel Ireland). Quasi-static (QS) tests were conducted. The lap shear strength was evaluated, and the failure mechanisms of the different joints were examined for the range of surface treatments considered. It was found that the performances of the PEEK and PPS joints were considerably improved by the plasma and UV treatments resulting in cohesive and delamination failures, while PEI was unaffected by the plasma and UV treatments and performed very well throughout.

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