Could static cling help keep clothes clean ? A cross between sparky carpets and microwave plasma ashing- oxidizing organic materials like wood or paper with a cold glow in a microwave oven may give rise to the ultimate form of dry cleaning.
The idea is to create reactive oxygen atoms to chew up dirt by allowing light to generate photoelectrons in or on the fiber surface using a dusting of semiconductor crystals. Natural fibers like silk and wool are cherished for strength, warmth, water resistance, and texture. But the proteins of which they are made, like keratin, lack the stain resistance of slick synthetics, and can't stand harsh chemical cleaning.
Monash University and Hong Kong Polytechnic now have a way to make keratin fibers that clean themselves by modifying them with Titanium oxide ( TiO2 ) nanoparticles .Daoud et al., report in Chemistry of Materials (2008) 20, 1242].
They functionalized wool with carboxylic groups using succinic anhydride, a mild acylating agent , making the fibers adherent for anatase TiO2 nanocrystals- a finer form of the white paint pigment . TiO2 is an efficient photocatalyst , and red wine stains on the wool dissapeared on exposure to a solar light simulator,
Walid A. Daoud says: “Among the different crystalline forms of TiO2, the anatase form shows the highest photocatalytic ability,” “Biomaterials such as keratins are subject to photodegradation in presence of sunlight. They also have poor resistance to heat and strong chemicals and solvents. The nanocrystals reduce their photodegradation by absorbing the light and converting it into self-cleaning power to decompose contamination.”
Nanocrystalline anatase was chosen because the small particles higher surface area yields a higher efficiency of photocatalysis, and the nanoparticles are so small as to be invisible. They do not alter the fabric's texture, color, or feel.