2008-4-14
Key words
Aerogels, nonwovens, thermal insulation
Introduction
An important growth area for nonwovens is in the thermal personal protection sector. Low temperature protective articles should provide good thermal insulation and ideally allow the transport of water vapour through the fabric. Applications include linings in outdoor pursuit garments, low temperature workwear and Personal Protective Equipment (PPE) as well as sleeping bags. There is a considerable body of research concerned with fabric insulation and the mechanisms of heat transfer in clothing systems. It is known that the thermal insulation depends on fabric thickness and density. Nonwovens can entrap large volumes of still air, which has a low conductivity of 0.025 W/mK and the fabric structure can be engineered to minimise heat transfer by convection currents thereby increasing thermal insulation. Since the volume of entrapped air influences the thermal insulation, the traditional approach to achieving good insulation is to construct thick, low density fabrics. Consequently, thermal protective fabrics in use tend to be thick and bulky, which may compromise other aspects of garments functionality as well as wearer comfort.
About the Authors:
The authors are associated with Nonwovens Research Group, Centre for Technical Textiles, University of Leeds, UK.
About the Source:
Reproduced courtesy of INDA [1], Association of the Nonwoven Fabrics Industry
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