Application of Technical Textiles in Everyday Life

Medical Textiles

An important and growing part of the textile industry is the medical and related healthcare and hygiene sector. The extent of the growth is due to constant improvements and innovations in both textile technology and medical procedures. Combination of textile technology and medical sciences has resulted into a new field called medical textiles. New areas of application for medical textiles have been identified with the development of new fibers and manufacturing technologies for yarns and fabrics.

Textile materials and products that have been engineered to meet particular needs, are suitable for any medical and surgical application where a combination of strength, flexibility, and sometimes moisture and air permeability are required. Materials used include monofilament and multifilament yarns, woven, knitted, and nonwoven fabrics, and composite structures. The number of applications are huge and diverse, ranging from a single thread suture to the complex composite structures for bone replacement, and from the simple cleaning wipe to advanced barrier fabrics used in operating rooms.

Although textile materials have been widely adopted in medical and surgical applications for many years, new uses are still being found. Research utilising new and existing fibres and fabric-forming techniques has led to the advancement of medical and surgical textiles. At the forefront of these developments are the fibre manufacturers who produce a variety of fibres whose properties govern the product and the ultimate application, whether the requirement is absorbency, tenacity flexibility, softness, or biodegradability.

Development in the field of textiles, either natural or manmade textiles, normally aimed at how they enhance the comfort to the users.

Fibres used

Commodity fibres

Fibres used in medicine and surgery may be classified depending on whether the materials from which they are made are natural or synthetic, biodegradable or nonbiodegradable. All fibres used in medical applications must be non-toxic, nonallergenic non-carcinogenic, and be able to be sterilised without imparting any change in the physical or chemical characteristics. Commonly used natural fibres are cotton and silk but also included are the regenerated cellulosic fibres (viscose rayon); these are widely used in nonimplantable materials and healthcare/hygiene products.

A wide variety of products and specific applications utilise the unique characteristics that synthetic fibres exhibit. Commonly used synthetic materials include polyester, polyamide, polytetrafluoroethylene (PTFE), polypropylene, carbon, glass, and so on. The second classification relates to the extent of fibre biodegradability. Biodegradable fibres are those which are absorbed by the body within 2–3 months after implantation and include cotton, viscose rayon, polyamide, polyurethane, collagen, and alginate. Fibres that are slowly absorbed within the body and take more than 6 months to degrade are considered non biodegradable and include polyester (e.g. Dacron), polypropylene, PTFE and carbon.

Speciality fibres

A variety of natural polymers such as collagen, alginate, chitin, chitosan, and so on, have been found to be essential materials for modern wound dressings. Collagen, which is obtained from bovine skin, is a protein available either in fibre or hydrogel (gelatin) form. Collagen fibres, used as sutures, are as strong as silk and are biodegradable. The transparent hydrogel that is formed when collagen is crosslinked in 5–10% aqueous solution, has a high oxygen permeability and can be processed into soft contact lenses. Calcium alginate fibres are produced from seaweed of the type Laminariae.

The fibres possess healing properties, which have proved to be effective in the treatment of a wide variety of wounds, and dressings. comprising calcium alginate are non-toxic, biodegradable and haemostatic. Chitin, a polysaccharide that is obtained from crab and shrimp shells, has excellent antithrombogenic characteristics, and can be absorbed by the body and promote healing. Chitin nonwoven fabrics used as artificial skin adhere to the body stimulating new skin formation which accelerates the healing rate and reduces pain.Treatment of chitin with alkali yields chitosan that can be spun into filaments of similar strength to viscose rayon. Chitosan is now being developed for slow drug-release membranes. Other fibres that have been developed include polycaprolactone (PCL) and polypropiolactone (PPL), which can be mixed with cellulosic fibres to produce highly flexible and inexpensive biodegradable nonwovens. Melt spun fibres made from lactic acid have similar strength and heat properties as nylon and are also biodegradable. Microbiocidal compositions that inhibit the growth of microorganisms can be applied on to natural fibres as coatings or incorporated directly into artificial fibres.

Materials Used For Medical Textiles

The textile materials especially for medical purpose can be termed as Bio materials. It can be defined as materials that are used in contact with tissue, blood, cells, protein and living substance. Bio materials include metals, ceramics, polymers, natural fibers. The following chart gives an overall idea of textile materials used for medical applications.

Characteristics of materials for medical use

The major requirements for biomedical polymers

• Non toxicity
• Nonallergenic response
• The ability to be sterilized
• Mechanical properties
• Strength
• Elasticity
• Durability
• Biocompatibility

As biomedical materials may be contaminated with bacteria, sterilization is important for biomedical polymers. The sterilization technique can be physical or chemical.

Textile Materials used in Medical applications

Textile Materials in the form of Fiber, yarn, Woven cloth, Knitted fabrics, Non wovens and composites are used in medical field according to their end uses. Hollow fibers are the latest developments in textile field for medical use.

Classification Of Medical Textiles

These are the textile products for medical applications include materials as fibres, yarns, woven, knitted, nonwoven, PTFE felts and mesh etc.

Depending upon the usage, they are classified as

1. Healthcare and Hygiene products
2. Extracorporeal devices
3. Implantable materials
4. Non-implantable materials

Medical textiles can be classified as follows:

End-uses of Medical Textiles

The textile products according to the end uses in medical field may be classified in a broad manner as follows:

The Use of cloth in medical application is known since ages and the development of various man made fibers changed the scenario of application for medical purposes in various ways.

 

Fibres used for medical and healthcare application

Textiles materials that are used in medical applications include fibres, yarns, fabrics and composites. Depending upon the application, the major requirements of medical textiles are absorbency, tenacity, flexibility, softness and at times biostability or biodegradability. Fibres used in medical field may vary from natural fibre such as cotton, silk, regenerated wood fluff (absorbent layer), to, manmade fibres like polyester, polyamide, polyethylene, glass etc.(Table 4.1)

Table 4.1 The various applications of different fibre in medical field