NANOFINISHES FOR UV PROTECTION IN

TEXTILESMYTHILI TUMMALAPALLI

2010TTZ8217

SUBMITTED TODR. BHUVANESH GUPTA

INTRODUCTION

UVA (320 to 400 nm)

UVB (290 to 320 nm)

UVC (200 to 290 nm)

UV-B irradiance at the surface based on the abundance of ozone, as measured by NASA’s Total Ozone Mapping

Spectrometer (TOMS) instrument during the month of November, 2000.

Courtesy: http://www.cushnshade.com

INDUSTRIAL SCENARIO

Aerospace

Aviation

Petrochemical

Electronics

Machinery

Environment

Protection..

Ultraviolet Protection Factor (UPF)

EVALUATION OF UV PROTECTION

Eλ = erythemal spectral effectivenessSλ = solar spectral irradiance in W/m2/nmTλ = spectral transmittance of fabricΔ λ = the bandwidth in nmλ = the wavelength in nm

Solar Protection Factor (SPF)

MED = Minimum Erythrymal Dose

Higher the UPF and SPF values, better the UV protection by the fabric

Courtesy: http://www.cushnshade.com

UV PROTECTIVE TEXTILES

Fiber chemistry

Fabric construction, porosity, thickness and weight;

Moisture content

Dye concentration, whitening agents, UV absorbers

Finishing chemicals

FACTORS – UV PROTECTION

METHODS OF UV PROTECTION IN TEXTILES

UV absorbers Colors

Finishes - - NANO

Nanotechnology - structures sized between 1 to 100 nm in at least one dimension

ZnO, TiO2 , ZrO - absorb the UV radiation

ZnO, TiO2 - non-toxic, compatible with human skin, chemically stable under both high temp. and UVR, easily available

NANOFINISHES

High surface-to-volume ratio - adhere well to the fabric

Transparent appearance

High surface area and high surface energy - bound to the surface of the fibres by van der Waals forces - wash fastness

Continued…

Cotton/polyester

Higher UPF

Woven better UPF than knitted

Polyester/cotton blend - better UPF than pure cotton - UV absorption of polyester

APPLICATION OF NANO ZnO BY PADDING MANGLE

Karthivelu et al., Indian Journal of Fibre & Textile Research, Vol. 34, September 2009, pg. 267-273

Hexamethyelenetetramine and zincnitrate

Cotton fabric - treated in hot water to obtain 1D needle-shaped nano ZnO crystallites

ZnO ON SiO2 SOL COATED COTTON - HYDROTHERMAL METHOD

DEVELOPMENT OF NANO ZnO PARTICLES – SEM IMAGES

(a) before treatment, (b) after soaking in the SiO2 solution, (c) after chemical deposition of ZnO, and (d) after hot water treatment at 100 °C for 2.5 h

(a) before treatment, (b) after soaking in the SiO2 solution, (c) after chemical deposition of ZnO, and (d) after hotwater treatment at 100 °C for 2.5 h.

(a) before treatment, (b) after soaking in the SiO2 solution, chemical deposition of ZnO, and boiling water treatment for 3 h, and (c) after 20 washes

Mao et al., Thin Solid Films, Vol. 517, 2009, pg. 2681–2686

CeO2 -excellent UV absorption - low photocatalytic activity

CeO2 + ZnO - reduce the catalytic and photocatalytic activities

Fine ZnO:CeO2 particles with very small size - unique UV absorbing ability, high stability at high temp., high hardness, and low activity as catalyst

ZnO:CeO2 NANOPOWDERS AS UV ABSORBERS

J. F. Lima et al., Applied Surface Science, Vol. 255, 2009, pg. 9006–9009

Layered fabric systems with electrospun ZnO nanocomposite fiber webs - various conc of ZnO in a range of web area densities

Extremely thin, Light-weight, Mechanically flexible

Desired functionalities imparted without significant increases in weight or thickness

ELECTROSPUN ZnONANOCOMPOSITE FIBERS

SEM micrographs of (a) electrospun polyurethane nanofiber web, (b) electrospun polyurethane/ZnO nanocomposite fiber web and the cross-sectional view of a nanocomposite fiber (inset), and (c) cross-sectional view of a layered fabric system

S. Lee, Fibers and Polymers, Vol.10, No.3, 2009, pg. 295-301

Anti microbial + UV protective

POLYESTER WITH ALGINATES & TiO2 NANOPARTICLES

Transmission spectra of PES fabrics loaded of with TiO2 nanoparticles

D. Mihailovic et al., Carbohydrate Polymers, Vol. 79, 2010, pg. 526–532

Particle-embedded acrylic coatings transparent to visible light but absorb UVR

UV absorption behavior of nano- and micron size particles

Thick coatings of 10 μm and 20 μm applied to Kevlar fabrics

TiO2 EMBEDDED ACRYLIC COATINGS ON KEVLAR

Absorption spectra from various size TiO2 particles

P. Katangur et al., Polymer Degradation and Stability, Vol. 91, 2006, pg. 2437 – 2442

Cotton, Polyester, Cotton/Polyester Blend – Coated with ZnO – Gamma Irradiation for curing

UPF increased with an increase in the concentration of the UV absorber

USE OF GAMMA RADIATION

M. H. Zohdy et al., European Polymer Journal, Vol. 45, 2009, pg. 2926–2934

SEM micrographs of (a) uncoated polyester fabrics (b) ZnO coated polyester

SEM micrographs of (a) untreated Cotton fabrics (b) Alum/ZnO coated fabric

UPF &UV transmittance of coated PET fabrics

UPF & UV transmittanceof coated cotton fabrics

Large surface area – better UV absorption

Transparent appearance on coatings

Applied using different techniques

Reasonable wash fastness

Can be used to produce multifunctional components

CONCLUSION

Richard A. Scott, “Textiles for Protection,” Woodhead Publishing Limited, 2005.

D. Saravanan, AUTEX Research Journal, Vol. 7, No 1, March 2007.

Hoffmann et al., Arch Dermatol, Vol. 137, August 2001.

Karthivelu et al., Indian Journal of Fibre & Textile Research, Vol. 34, September 2009, pg. 267-273.

Mao et al., Thin Solid Films, Vol. 517, 2009, pg. 2681–2686.

J. F. Lima et al., Applied Surface Science, Vol. 255, 2009, pg. 9006–9009.

S. Lee, Fibers and Polymers, Vol.10, No.3, 2009, pg. 295-301.

D. Mihailovic et al., Carbohydrate Polymers, Vol. 79, 2010, pg. 526–532.

P. Katangur et al., Polymer Degradation and Stability, Vol. 91, 2006, pg. 2437 - 2442.

H. Zhang et al., Polymer Degradation and Stability, Vol. 94, 2009, pg. 278–283.

M. H. Zohdy et al., European Polymer Journal, Vol. 45, 2009, pg. 2926–2934.

www.wikipedia.org

Fernando et al., Nanotechnology Applications in Coatings, ACS Symposium Series, American Chemical Society, Washington D.C., 2009.

M. D. Newman et al., Journal of American Academy of Dermatology, October 2009.

REFERENCES

THANK YOU