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High Performance Technical Textiles: An Overview

Roshan Paul

University of Beira Interior, Covilhã, Portugal

1.1 Introduction

Technical textiles provide technical, functional, and performance properties, unlike textiles used in the fashion, artistic, or decorative sectors. These include textiles for households, packaging, sports, medical, protection, military, filtration, geotextiles, agriculture, construction, automotive, marine, aeronautic, and other smart applications. Synthetic as well as nanofibres - like aramid, polyolefin, polyamide, polyester (PES), viscose, glass, and ceramic fibres - are widely used for the manufacture of technical textiles. Nanofibre nonwovens can also improve the properties of textiles designed for technical applications.

Natural and bast fibres like jute, flax, hemp, coir, ramie, kenaf, and abaca are also finding applications as technical textiles for environmental reasons. They are gaining increasing importance particularly as fibre reinforced composites in automotive, construction, aerospace, and packaging industries. This is mainly due to the fact that bast fibres offer good tensile strength and stiffness compared to synthetic fibres such as polyamide, carbon, and aramid. Besides, they originate from renewable natural resources and are environmentally friendly.

1.2 Application Areas of Technical Textiles

In general, application areas of technical textiles are classified as:

• Hometech. Carpet components, furniture components, consumer and industrial wipes, air and water filtration, interior design, drapes, covers, ticking, composites, etc.
• Packtech. Bulk packaging with a predefined three-dimensional (3D) structure, scrap and disposable, spacer and tying, absorbent food pads, etc.
• Sporttech. Luggage components, sports equipment, sportswear, wipes, covers, disposable, and camping equipment, etc.
• Medtech. Drapes and gowns, sterile wrap, swabs and dressing, cleaning products, cover stock, wound care, protective apparel, bedding and sheets and masks, etc.
• Protech. Chemical and biological protection, particulate protection, flame retardant, cut resistant, shields and gowns worn in emergency situations, chemical handling, hazardous waste control, cleaning, filtration, etc.
• Clothtech. Cleanroom garments, shoe components, insulation and structure, sewing products, interlining, leather goods applications, etc.
• Indutech. Electrical components, filtration and separation, satellite dishes, clothing surfacing tissues/veils, conveyor belts, reinforced plastics, polyvinyl chloride () substrates, flame barriers, noise absorbents, battery separators, antislip matting, lifting and pulling, etc.
• Geotech. Asphalt overlay, soil stabilization, drainage, sedimentation and erosion control, pond liner, impregnation base, drainage channel liners, separation, reinforcement, filtration, offshore land reclamation, roadside, railside, river and canal banks, reservoirs, etc.
• Oekotech. Environmental protection, exhaust air and waste water filtration, dust collection, oil and fuel absorbent, gas and odour removal, etc.
• Agrotech. Crop covers, seed blankets, weed control fabrics, greenhouse shading, root bags, biodegradable plant pots, capillary matting cover, protection and collection, fishing, etc.
• Buildtech. Roofing and tile underlay, underslating, thermal and noise insulation, house wrap, facings for plaster board, pipe wrap, concrete moulding layers, foundations and ground stabilization, vertical drainage, protection and display, textile construction, building components, reinforcements, high quality wallpapers, etc.
• Mobiltech. Boot liners, parcel shelves, heat shields, shelf trim, moulded bonnet liners, boot floor covering, fuel/oil filters, headliners, rear parcel shelves, airbags, cabin air filters, engine intake and exhaust air filters, silencer pads, insulation materials, car covers, under padding, car mats, tapes, backing for tufted carpets, seat covers, door trim and insulation, floor coverings, protection, composites, etc.

1.3 Technical Textiles by Functional Finishing

It is a general concept that technical textiles are manufactured using technical fibres, with inherent technical properties. But innovative functional finishes are creating possibilities for developing functional technical textiles by a simple finish application at the end of the textile manufacturing process. The modification of commodity fibre and fabric properties by innovative finishes can be a cheaper route to high performance than by using high cost fibres with inherent built in performance properties. In a textile industry, finishing is usually done in the final stage of textile processing. A wide variety of functional properties can be created on textiles by means of chemical or bio finishing and also it is possible to develop multifunctional textiles.

With the advent of nanotechnology, a new area has developed in the realm of textile finishing. Nanotechnology is opening new avenues in chemical finishing, resulting either in improved processes or in helping to achieve new functional properties, which were not possible with conventional finishes. Thus, the application of nanotechnology creates an expanded array of functional properties enabling textiles to be used in novel materials and products. Unlike in conventional finishing, the nanometric size of the coating will not affect negatively the hand and feel of the finished fabric. The low temperature sol-gel techniques, as well as the new generation of polymeric resins, are offering new possibilities in textile chemical finishing.

Another important development is the plasma enhanced chemical vapour deposition () technique. It is a finishing process which can be used to deposit thin solid polymeric films from a gas state to a solid state on a textile substrate to achieve the desired properties. The advantage of such plasma treatments is that the modification turns out to be restricted to the uppermost layers of the substrate, thus not affecting the overall bulk properties. In general, plasma treatment can be considered as a dry alternative to the wet chemical treatments and so they are environmentally friendly. Layer by layer () assembly method is another new finishing technique by which ultrathin composite films can be developed on solid surfaces like textiles. It involves an LbL adsorption of polycations and polyanions to build a multilayer ultrathin polyelectrolyte coating on a textile substrate.

1.4 High Performance Technical Textiles

This book on high performance technical textiles covers almost all the important areas of technical textiles. The book starts with household and packaging textiles, hi-tech sports textiles, and medical textiles. Further, it focuses on the protective aspects, with chapters on protective textiles, personal protective clothing, and military textiles. Industrial and filtration textiles, geotextiles, and agrotextiles are dealt with in the subsequent chapters. Important application areas like construction, automotive, marine, aeronautic, and space are covered in the following chapters. The last chapter talks exclusively about smart and responsive textiles.

1.4.1 Household and Packaging Textiles

Textiles have become an integral part of the home, both in daily use and in household installations. Household textiles include carpets, sheets, pillow cases, pillows, blankets and quilts, bedspreads, table linens, bathroom and kitchen towels, bathmats, shower curtains, readymade and custom made curtains, draperies, slipcovers, and other furniture protectors. They make life more comfortable and give home interiors a defined aesthetic characteristic.

Technological innovations have converted conventional household textiles into high performance textiles by improving their durability and by adding multiple functionalities, thus allowing them to follow trends in line with e-textiles, combining sustainable materials for easier disposal and reuse, and incorporating nanotechnology into everyday personal items. Hollow fibres with good insulation properties are broadly employed in bedding and sleeping bags. Other categories of fibre are increasingly being utilized to substitute foams in furniture because of the fear of fire and of health hazards created by such materials.

Packaging textiles include all textile packing material for industrial, agricultural, and other goods. Lightweight nonwoven and knitted materials are widely used for various wrapping and protection purposes, particularly in foodstuff industries. Growing environmental concern over reusable packages and containers is opening new opportunities for textile products in this area. Textiles have helped high performance packaging to advance as they can be engineered to have very strong weaving structures while being lightweight and more sustainable than conventional packaging materials. High performance textiles along with modern materials handling methods have permitted the innovation of more proficient handling, storing, and distribution of various powdered and granular merchandise varying from fertilizers, sand, cement, sugar, and flour to dyes and pigments. Packaging textiles have also entered a new era of active and intelligent systems which interact with their content and inform the consumer about spoilage risks or products'...