APPLICATION OF AEROGELS IN TEXTILE INDUSTRY

INTRODUCTION:-

‘Aerogel’ is a broad term used to talk about an extraordinary group of materials that have been used since the 1960’s in space travel, but are now finding uses across a whole range of industries; Textile being one of them. Aerogels are the world's lightest (least dense) solids. They are also excellent thermal insulators and have been used in numerous space missions by NASA.

Aerogels are made by evaporating liquid from gels. It is invented by Prof. Samuel Stephens Kistler in 1930, when his friend challenged him to remove the liquid from the jelly without affecting the solid structure. Aerogel are mainly three types i.e. silica, carbon and metal oxides. Silica aerogel used for insulation, carbon aerogels useful for super capacitors, fuel cells and desalination systems, metal oxides aerogel are also used in the production of explosives and carbon nanotubes.
Silica aerogels are used in textile industries due to its incredible insulating properties. But we can’t use raw, pure silica aerogel since it is very brittle in nature. However the unique properties of silica aerogels are extremely useful when it is reinforced with other materials like fiber to form composites. These composite materials have excellent insulating properties due to their low thermal conductivity [0.017-0.021W/mK] .They are used for insulating at high temperature as well as at cryogenic temperature[-150 °C to -273 °C].

Composite Aerogel Sheets

Properties of Aerogel:-

Applications in Textile:-

Aerogels can be used for the development of wide variety high performance products such as Antibacterial textiles, medical textiles, insulating building and pipe line, fire retardant textiles, intelligent textile Composites, in Clothing & apparels such as Spacesuits, Jackets for protection from extreme cold weather conditions, Footwear, gloves, Green building, Packing materials and shipping containers, Other thermal insulating products.

• Insulating textiles:-
Aerogels have incredible insulating properties when they are reinforced with fibers. Aspen Aerogels has developed a range of aerogel blankets designed for different applications. Technically their materials are aerogel composites because they combine fibrous battings of inorganic or organic fibers with aerogels to use them for high-temperature as well as for low temperature applications. Aspen’s products can be found in subsea oil pipelines, refineries, winter apparel, and even shoe insoles. The comparison between aerogel insulation and conventionally used polyurethane foam (PUF) insulation used to keep the pipelines warm is shown in following image-

• Medical textile:-
Silica-biopolymer hybrids are in the form of films for membranes or coatings. It has biodegradable, bioadhesive with multifunctional properties. These hybrid materials find application in the field of biocompatible materials, bone substituent’s, cements for bone repair and reconstruction.

• Environmental applications:-
There is a growing demand for new, cheaper and more efficient materials for water treatment and air/gas stream cleaning. Aerogel-based products are developed in the form of absorbents, adsorbents or catalysts can give improved response to the capture and degradation of oil spills and various toxic compounds. Aerogel may prove superior in applications which target reducing greenhouse gas emissions. Researchers have also developed aerogel sound insulation material that outperforms existing products in this department. These aerogel-based materials for environmental applications should contribute to the reduction of water, air and noise pollution.

• Intelligent textiles:-

Aerogels can be used with smart textiles to design novel sol/gel products such as alumina silica piezoelectric aerogels in the field of energy harvesting carpets. These can convert the stresses acting upon it when people walk over it, in to usable form of energy to power a small battery; wall coverings and curtains which utilize the energy of wind to power an array of LEDs for indoor applications.

• Antibacterial Textiles:-
Aerogels can be used in textiles requiring antibacterial properties. Material with adaptive antibacterial killer based on sol/gels TiO2, which remains active in wet state only.

• Fire and Liquid repellant Textiles:-

Aerogels can also be used to impart flame retardant finishes to fabrics for example coatings of protective clothing using aerogels. Heat transfer by the gas phase could be avoided by evacuation. Evacuated Silica aerogel showed reduced thermal conductivity. Aerogels can also be utilized for development of novel anti-wetting coatings on textiles such as silica-biopolymer coatings to render highly hydrophobic characteristics to the fabrics.

• Green building:-
As the energy use in the building sector for heating or cooling accounts for a significant proportion of the world’s total energy consumption and greenhouse gas emissions, there is a demand to improve the energy efficiency of buildings. Hence, in this respect, Aerogel composites are being explored to reduce the energy consumption in households and industries. Initial studies have shown that aerogel blanket can reduce energy consumption for heating or cooling the interior of a fabric structure by 30 to 70%, depending on the climate.

• Apparel Textile:-
Aerogels have two to six times more insulating power than other commonly used materials. Mount Everest climbers have used aerogel insoles, as well as sleeping bags. The “pyrogel” insulation developed by Aspen Aerogel Inc. has been proven to be an effective underfoot barrier to extreme cold in the form of insoles for climbers, where their light weight and flexibility are extremely useful.
Oros Apparel’s Orion line, composed of a jacket, snow pants and gloves made by their own Solarcore technology based on aerogels. To test the insulating qualities of SolarCore, Oros blasted a jacket with liquid nitrogen to bring the outside temperature down to -321 degrees Fahrenheit, while the inside remained a toasty 89 F.

Conclusion:-

Aerogel is one of the most promising thermal insulation materials of the last decades. If one may be able to manufacture aerogel for a fraction of the current costs, aerogel insulation maybe widely used as appropriate alternative to current traditional insulation materials. Beside its insulating properties aerogel composite also have applications in medical, environmental, fire retardant, antibacterial and apparel textiles. Because of their application in intelligent textiles energy harvesting from stresses is also possible. Still there are many possible uses of aerogel, which requires further research and development.

References:-

-https://www.azom.com/article.aspx?ArticleID=6499.

-https://technology.nasa.gov/patent/TOP3-413
https://link.springer.com/article/10.1007/s10971-018-4796-6.

-https://en.wikipedia.org/wiki/Aerogel.

-http://www.indiantextilejournal.com/articles/FAdetails.asp?id=4154.

-http://www.aerogel.org/

-Chemical and Process Engineering Research www.iiste.org ISSN 2224-7467 (Paper) ISSN 2225-0913 (Online) Vol.9, 2013 AEROGEL – A Promising Building Material for Sustainable Building.

-The Pharma Innovation Journal 2019; 8(2): 329-332 Use of aerogel in textile and apparel industry.

-Anonymous, Aerogel Insulation for Building Applications by Bjørn Petter Jelle, Ruben Baetens, and Arild Gustavsen.

-Materials and Structures DOI 10.1617/s11527-015-0746-8 Anhydrite/aerogel composites for thermal insulation.

-Thermal Insulation of High Performance Fibrous Materials by Mohanapriya Venkataraman.

-Venkataraman, Mishra M, Kotresh R, Militky J, Jamshaid H. Comparative analysis of high performance thermal insulation materials.

APPLICATION OF AEROGELS IN TEXTILE INDUSTRY