An investigation of polypyrrole coated conductive textiles

This research first clarified a possible chemical reaction between a dispersing dye and the conducting polymer polypyrrole. Then, the effect of acidic dyes as dopants on the colours, conductivity and thermal stability of polypyrrole were measured. Finally, the polypyrrole nanoparticles were prepared by a microemulsion polymerisation technique.

Novel conducting polymer films and coated textiles

This research developed non-hazardous methods for coating wool with conductive polymers for thermal and anti-static clothing. Conductive polymers are black in colour, thus the synthesis of new conductive polymers was required to produce coloured or fluorescent conductive textile. Cross-linked conductive polymers were also synthesised to increase their durability.

Characteristcs of conducting textiles in the microwave frequency range

This investigation of textiles coated with a polymer that conducts electricity showed that they can be used for effectively reflecting and absorbing microwaves. These conducting textiles are an economical, flexible and lightweight alternative to traditional materials for electromagnetic interference shielding of, for instance, sensitive electronic equipment.

Recent research on natural fibres and textiles

This paper provides an overview of recent research on a range of natural fibres and textiles. The focus is on work carried out at Deakin University’s Centre for Material and Fibre Innovation, which is a multidisciplinary research centre with over 100 researchers. The fibres include hemp, wool, silk, and alpaca fibres. Research on yarns, fabrics, and fine powders made from wool and silk fibres are briefly discussed also.

The within-fibre diameter variation of wool has been examined systematically, which highlights the importance of this hard-to-measure fibre attribute. A relationship between hemp fibre fineness and residual gum content has been established, which provides a rapid means of assessing the residual gum content in the degummed hemp fibres. Silk and wool fibres have been converted into ultrafine powders for advanced applications. The Resistance to Compression (RtC) behaviour of wool and alpaca fibres has been closely examined, which challenges the belief that RtC is a good indicator of fibre softness. Ways of reducing the hairiness of natural fibre yarns, predicting the pilling propensity of wool knits, and functionalising fabrics for superhydrophobicity and photochromic or colour changing effects are discussed.

Photochromic textiles from hybrid silica coating with improved photostability

Photochromic surface coating on textiles may create new fashion opportunities. It also enhances the ultraviolet (UV) protection ability of the coated products. In this study, a spirooxazine dye and a silane that bears a long alkyl chain have been used to produce hybrid photochromic silica coatings on wool fabrics. Four stabilisers are added separately to the photochromic silica coatings to examine their influence on photostability and photochromic behaviour. It is found that the addition of UV stabilisers slightly reduces the photochromic response speed and photochromic absorption. However, the addition of UV stabilisers to the photochromic coating considerably improves the photochromic lifetime. Among the four UV stabilisers studied, the quencher results in the best improvement to photostability with the lowest reduction in photochromic absorption.

An investigation of polypyrrole coated conductive textiles: this research aimed at clarifying some issues occurred in the research project on coloured conductive textiles

Coloured conducting textiles have shown a wide range of potential applications in heating fabrics, electromagnetic wave absorption, and wearable optoelectronic devices. This research aimed at clarifying some issues occurred in the research project on coloured conductive textiles. The investigation firstly clarified a possible chemical reaction that took place between a commercial dispersing dye (Terasil Red G) and the conducting polymer polypyrrole, through chemical separation, structural identification and spectrum characterisations. Then, a series of acidic dyes were introduced into polypyrrole matrix during the vapour coating of conducting polymer on the wool fabrics. Colour and thermal stability studies were conducted. Finally, the polypyrrole nanoparticles (particle size several~200nm) were prepared by a microemulsion polymerisation technique. An acid dye was used as the dopant to re-dope the nanoparticles. The effect of the acidic dye on the optical absorption of nanoparticles was studied. Applying the conducting nanoparticles on wool fabrics may open an alternative path to achieve the coloured conducting textiles.

Methods of coating textiles with soluble conducting polymers

Soluble conducting alkyl polypyrrole polymers have been applied by either chemical polymerization of the 3-alkyl monomers or direct application of polymer emulsion to the surface. Solution, vapor and spray polymerization methods of coating poly(3-alkylpyrroles) to the surface of woven wool fabrics are explored. Conductive textile samples have also been prepared by applying emulsions of soluble prepolymerized 3-alkylpyrrole to the fabric surface. Direct applications of a conductive paint to the textile surface eliminate the exposure of the substrate to damaging oxidizing agents which allow the coating of more sensitive and delicate substrates. All textiles produced are tested for abrasion resistance and conductivity. For alkyl polypyrrole coated fabrics, the optimum carbon chain lengths are between n=10 and n=14, which result in optimum values of conductivity and solubility. The darkness of the tone is inversely related to the surface resistivity of the resulting conductive fabric. Therefore, deep black coatings have low resistivity whereas light gray coatings on a white fabric surface have higher surface resistivity. Longer alkyl chains result in higher surface resistivity in fabrics. The conductive coating of poly(3-decanylpyrrole) on the textile surface has a better abrasion resistance compared to that of an unsubstituted polypyrrole coating.

Mohair research update 17 : wearer comfort of mohair textiles - does mohair have an allergy problem?

Many aspects of textiles affect the comfort or discomfort experienced by people. The effects of variations in thermal, moisture transmission, air permeability, size, fit, aesthetics and static electrical properties on textiles have been known for many years (Slater, 1977). Problems experienced with wearer comfort, both sensory and functional, have increased in commercial importance for all animal fibres. Surveys have shown that consumers report that prickle discomfort from wearing wool next to the skin is a negative market attribute for wool (IWS, 1993; Millard Brown, 2007).

Recyclable textiles functionalized with reduced graphene Oxide@ZnO for removal of oil spills and dye pollutants

A novel recyclable and flexible membrane was prepared for the removal of oil spills and organic dye pollutants, by functionalizing polyester textiles with reduced graphene oxide@ZnO nanocomposites using a layer-by-layer technique. The membrane showed efficient water/oil separation, and the amount of oil adsorbed by the membrane could be up to 23 times its own weight. The adsorption capacity was largely retained during many adsorption recycling cycles. The membrane also displayed highly efficient removal of a dye pollutant from water under simulated sunlight. The membrane maintained a near-original removal efficiency after five cycles of dye removal. This new type of membrane may find practical applications in the large-scale separation of organic pollutants from water, particularly in the field of oil spills clean-up and dye removal from industrial effluent.

Scalable One-Step Wet-Spinning of Graphene Fibers and Yarns from Liquid Crystalline Dispersions of Graphene Oxide: Towards Multifunctional Textiles

Key points in the formation of liquid crystalline (LC) dispersions of graphene oxide (GO) and their processability via wet-spinning to produce long lengths of micrometer-dimensional fibers and yarns are addressed. Based on rheological and polarized optical microscopy investigations, a rational relation between GO sheet size and polydispersity, concentration, liquid crystallinity, and spinnability is proposed, leading to an understanding of lyotropic LC behavior and fiber spinnability. The knowledge gained from the straightforward formulation of LC GO “inks” in a range of processable concentrations enables the spinning of continuous conducting, strong, and robust fibers at concentrations as low as 0.075 wt%, eliminating the need for relatively concentrated spinning dope dispersions. The dilute LC GO dispersion is proven to be suitable for fiber spinning using a number of coagulation strategies, including non-solvent precipitation, dispersion destabilization, ionic cross-linking, and polyelectrolyte complexation. One-step continuous spinning of graphene fibers and yarns is introduced for the first time by in situ spinning of LC GO in basic coagulation baths (i.e., NaOH or KOH), eliminating the need for post-treatment processes. The thermal conductivity of these graphene fibers is found to be much higher than polycrystalline graphite and other types of 3D carbon based materials.

A review on the application of photocatalytic materials on textiles

Incorporation of functional additives is one of the most important ways of functionalizing textiles. Among the additives, photocatalyst has been used extensively in recent years. This paper reviews the current research status on application of photocatalysts in fibrous materials. The review concentrates on novel methods for coating various photocatalysts on textiles and properties of the photocatalyst-modified textiles. The fundamental limitations and future prospects of this research are also discussed.

Recycling textiles : The use of ionic liquids in the separation of cotton polyester blends

Textiles are commonly made from intimate blends of polyester and cotton, which makes recycling very difficult. We report for the first time the use of ionic liquid in the separation of polyester cotton blends. By selective dissolution of the cotton component, the polyester component can be separated and recovered in high yield. This finding presents an environmentally benign approach to recycling textile waste. © 2014 The Royal Society of Chemistry.