Protective clothing textile fibres

Many of the innovations in textile applications in the past 50 years have started with military applications - from fibreglass structures for radomes, to fragment and bullet resistant body armour, to chemical agent protective clothing, to fibre-reinforced composites - indeed, many of our current defence systems and advanced aircraft would not be possible without these materials. So perhaps it is not surprising that the initial applications for smart textiles have also come either directly from military R D or from spin-offs. Some of... 

Polybenzimidazole fibre forms one of the most fire-resistant textiles (mp 760 °C usable to 540 °C) and, although very expeusive, is used for high-tech applicatious, such as protective clothing for fire fighters, astronauts and motor-racing drivers. 

Flame retardant finish for technical wool fabrics. Within the technical textile sector, wool textiles requiring high levels of heat and flame resistance are limited in the main to the contract and transport furnishing fabric and protective clothing markets. The non-thermoplastic and char-forming characteristics of wool, coupled with an inherently quite high level of low flanunabiUty, make it an ideal fibre when handle, comfort, and aesthetics are also required. 

Inherently FR polyamide fibres. Nylon or polyamide 6.6 has a higher melting point and superior tensile properties to polyamide 6 and so has the better characteristics to offer technical textiles. However, and in spite of the considerable research over the last 40 years, at the present time only one flame retardant polyamide 6.6 appears to available, which is Nexylon FR, EMS-GRILTECH of unknown composition, announced in September 2012. This fusible fibre is currently being aimed at the protective clothing and workwear markets but such applications will require flame retardancy as their primary property rather than heat protection. 

One further and final area of possible development will be in the smart textile field where there is a desire for fibres which may have a heat-sensing property which may then enable them to either alert the wearer (in protective clothing, for instance) or transfer electronic or other signals when embedded in a composite should a potential fire threat arise. This latter will be of increasing importance as the continued increase in use of textile and fibre-reinforced composites replaces conventional materials in the transport sectors, for example. 

Researchers have reported some properties of electrospun mats. They compared the performances of electrospun fibre mats with the properties of textiles and membranes currently used in protective clothing systems and showed that electrospun layers are extremely efficient for trapping airborne particles. Meanwhile, the air flow resistance and aerosol filtration properties are affected by the coating weight. It was shown that an extremely thin layer of electrospun nanofibres completely prevented particle penetration through the layer. 

Key words protective clothing, chemical protective clothing (CPC), fire fighter s clothing, textile materials, high performance fibres, membrane, protection, activated carbon, comfort, thermophysiological comfort. 

New materials and designs have been developed for heat protective clothing. For example, improved thermal insulation can be provided by non-wovens made with thin hollowed fibres, and can be made thermo-adaptive with two-way shape memory alloys such as nickel-titanium. Better thermoregulation inside the garment is sought with PCM, either encapsulated ° or incorporated in a matrix. Other solutions use external power, e.g., for liquid coolant circulation or with Peltier cells embedded in the textile. ... 

Suri M, Rastogi D and Khanna K (2002), Development of protective clothing for pesticide industry part II , Indian Journal of Fibre Textile Research, 27(9), pp. 259-265. 

Zylon or PBO is a more recently developed fibre than PBI and has outstanding tensile properties, as well as thermal and fire properties superior to any of the polymer-based fibres mentioned in this chapter (see Table 4.2). While there are at least two variants of the fibre, Zylon-AS and Zylon-HM, of which the latter has the higher modulus, both have the same thermal and burning parameter values. Principal examples of thermally protective textiles include heat protective clothing and aircraft fragment/heat barriers, where its price, similar to that of PBI, restricts its use to applications where strength, modulus and fire resistance are at a premium. 

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