427
rily for components for which high temperatures are commonplace,
such as exhaust systems.
antifogging, antireflection,
and other Characteristics
A whole host of other kinds of desired material behaviors are possible. Many antifogging applications depend on the hydrophilic
action of surfaces; the resulting spreading of water droplets
becomes largely invisible. Many films and glasses appear to possess
different reflective properties that are highly unique. In the optical
area, one of the most common is that of antireflection. Nanoproducts with antireflection characteristics are widely used in architecture as well as in product design to reduce troublesome reflections.
They are also used in optical devices to increase light transmission.
(Decreased reflection leads to increased light transmission.) Many
of these optically related products also can block specific types of
infrared, visible, or ultraviolet light wavelengths and thus be useful
in a wide array of applications. Section 9.5 describes these optical
effects in greater detail.
10.3 “smart” Behaviors
Earlier chapters dealt extensively with the properties of nanomaterials but only marginally addressed many of the dynamic material
behaviors—or smart behaviors, as they are often called—that designers or engineers need or desire and that are closely related to specific
mechanical, thermal, optical, or other property characteristics (also
see Section 9.8 on smart environments). The focus in this section is
not on properties but on specific desired material behaviors, such
as color changing or shape changing. A list of common behaviors is
shown in Figure 10.27.
A number of materials have an apparent ability to change one
or more of their properties in response to the input of thermal,
radiant, electrical, mechanical, or chemical energy from an outside
source. Thermochromics, for example, change their apparent color
as the temperature of their surrounding environment increases
and there is an input of thermal energy into the material, or magnetorheological materials change their viscosity when subjected to
varying levels of magnetic fields. The somewhat unfortunate term
smart materials has been widely used to describe materials that
exhibit these kinds of capabilities, as has the term responsive materials. In many of these materials, there is an apparent change in
certain properties of the material, such as changes in optical prop“Smart” Behaviors
rily for components for which high temperatures are commonplace,
such as exhaust systems.
antifogging, antireflection,
and other Characteristics
A whole host of other kinds of desired material behaviors are possible. Many antifogging applications depend on the hydrophilic
action of surfaces; the resulting spreading of water droplets
becomes largely invisible. Many films and glasses appear to possess
different reflective properties that are highly unique. In the optical
area, one of the most common is that of antireflection. Nanoproducts with antireflection characteristics are widely used in architecture as well as in product design to reduce troublesome reflections.
They are also used in optical devices to increase light transmission.
(Decreased reflection leads to increased light transmission.) Many
of these optically related products also can block specific types of
infrared, visible, or ultraviolet light wavelengths and thus be useful
in a wide array of applications. Section 9.5 describes these optical
effects in greater detail.
10.3 “smart” Behaviors
Earlier chapters dealt extensively with the properties of nanomaterials but only marginally addressed many of the dynamic material
behaviors—or smart behaviors, as they are often called—that designers or engineers need or desire and that are closely related to specific
mechanical, thermal, optical, or other property characteristics (also
see Section 9.8 on smart environments). The focus in this section is
not on properties but on specific desired material behaviors, such
as color changing or shape changing. A list of common behaviors is
shown in Figure 10.27.
A number of materials have an apparent ability to change one
or more of their properties in response to the input of thermal,
radiant, electrical, mechanical, or chemical energy from an outside
source. Thermochromics, for example, change their apparent color
as the temperature of their surrounding environment increases
and there is an input of thermal energy into the material, or magnetorheological materials change their viscosity when subjected to
varying levels of magnetic fields. The somewhat unfortunate term
smart materials has been widely used to describe materials that
exhibit these kinds of capabilities, as has the term responsive materials. In many of these materials, there is an apparent change in
certain properties of the material, such as changes in optical prop“Smart” Behaviors