C hapter 10 nanomaterial product Forms and Functions
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number of commercial products that are based in this approach
are already on the market—for example, photocatalytic acrylic
fibers used in yarn forms in various textiles.
Precise techniques for applying nanoparticles onto textiles vary but are
typically based on spraying, transfer printing, pressure-related padding,
and washing. As the industry looks forward, self-assembly approaches
appear to offer promising avenues of development, particularly as a
way of achieving more uniform fiber coatings. Self-cleaning textiles are
discussed more extensively in Section 10.4 on nanotextiles.
self-cleaning and antipollutant concrete
A highly interesting application for architects is the exploration
of self-cleaning concretes or mortars. Our societies use massive
amounts of concrete in the construction of buildings, bridges,
roads, and other works. Concrete surfaces are literally everywhere,
and one does not need to go far to find dirty, stained, and generally
awful-looking ones.
Many current approaches to keeping concrete clean generally rely
on either sealants that are preventive in character (see Section 10.4
on nanosealants) or other kinds of coatings that rely on some type
of hydrophilic or hydrophobic action for a self-cleaning action.
Coatings are often fairly thick since they also typically need to be
weather and abrasion resistant. They are also typically constituted
to be resistant to degradation induced by the ultraviolet (UV) component of sunlight.
A highly interesting approach mirrors that described in more detail
for self-cleaning applications in glass and other materials; it is the
use of photocatalytic particles that react to UV light and cause formation of oxidizing reagents that cause the decomposition of many
organic substances. In the case of concrete, the photocatalytic nanoparticles are directly mixed into the concrete or mortar mix at their
surfaces. The patented process developed by the Italcementi group
in Italy, for example, has been used in the exterior concrete façade
panels of the Jubilee Church (also known as the Dives in Misericordia) in Rome by American architect Richard Meirs and Partners
(see Figure 10.13). There are 256 precast, post-tensioned concrete
elements in the building. Similar applications have been made in
the new headquarters of Air France at Charles de Gaulle airport
and other places, including the Cité de la Musique et des Beaux
Arts in Chambéry and the Hotel de Police (see Figure 10.14). In this
process, titanium dioxide particles in the anatase form are mixed
in and provide the photocatalytic effect that causes dirt and other
organic matter on the surface to oxidize and degrade. Hydrophilic
416
number of commercial products that are based in this approach
are already on the market—for example, photocatalytic acrylic
fibers used in yarn forms in various textiles.
Precise techniques for applying nanoparticles onto textiles vary but are
typically based on spraying, transfer printing, pressure-related padding,
and washing. As the industry looks forward, self-assembly approaches
appear to offer promising avenues of development, particularly as a
way of achieving more uniform fiber coatings. Self-cleaning textiles are
discussed more extensively in Section 10.4 on nanotextiles.
self-cleaning and antipollutant concrete
A highly interesting application for architects is the exploration
of self-cleaning concretes or mortars. Our societies use massive
amounts of concrete in the construction of buildings, bridges,
roads, and other works. Concrete surfaces are literally everywhere,
and one does not need to go far to find dirty, stained, and generally
awful-looking ones.
Many current approaches to keeping concrete clean generally rely
on either sealants that are preventive in character (see Section 10.4
on nanosealants) or other kinds of coatings that rely on some type
of hydrophilic or hydrophobic action for a self-cleaning action.
Coatings are often fairly thick since they also typically need to be
weather and abrasion resistant. They are also typically constituted
to be resistant to degradation induced by the ultraviolet (UV) component of sunlight.
A highly interesting approach mirrors that described in more detail
for self-cleaning applications in glass and other materials; it is the
use of photocatalytic particles that react to UV light and cause formation of oxidizing reagents that cause the decomposition of many
organic substances. In the case of concrete, the photocatalytic nanoparticles are directly mixed into the concrete or mortar mix at their
surfaces. The patented process developed by the Italcementi group
in Italy, for example, has been used in the exterior concrete façade
panels of the Jubilee Church (also known as the Dives in Misericordia) in Rome by American architect Richard Meirs and Partners
(see Figure 10.13). There are 256 precast, post-tensioned concrete
elements in the building. Similar applications have been made in
the new headquarters of Air France at Charles de Gaulle airport
and other places, including the Cité de la Musique et des Beaux
Arts in Chambéry and the Hotel de Police (see Figure 10.14). In this
process, titanium dioxide particles in the anatase form are mixed
in and provide the photocatalytic effect that causes dirt and other
organic matter on the surface to oxidize and degrade. Hydrophilic