Silica nanoparticles make wool even more wonderful
By Darren Quick
December 22, 2009
Already regarded as a “wonder fabric” for its lightness, softness, warmth even when wet, and other qualities, scientists from China say they have been able to improve on the natural properties of wool. They say their discovery could give wool a “brain,” placing it among other “smart” fabrics that shake off wrinkles, shrinkage and “breathe” to release perspiration.
Wool’s natural water-repellency also acts as a barrier to enhanced features such as anti-wrinkle, anti-shrinkage finishing and dyeing. This property also hinders its ability to absorb moisture and makes wool garments feel sweaty.
Although scientists have developed treatments that make wool more hydrophilic, or water-absorbing, they may not last long, may damage the fabric, and are not environmentally-friendly.
By coating the wool with an ultrathin silica layer the scientists found they were able to make the wool more water-absorbing without the problems associated with existing treatments. The coating is made from silica nanoparticles 1/50,000th the width of a human hair. The particles altered both the surface roughness and surface energy of the fiber and endowed the wool fabrics with excellent water absorption. The new layer does not affect wool's color or texture and can withstand dry cleaning, the scientists note.