DiAPLEX can be called a material with self-control because
it senses changes in the environment and adjusts itself accordingly to maintain
comfortable in-garment condition. In addition to being highly waterproof and
effectively breathable, DiAPLEX also features anti-condensation
characteristics, heat retention, wind proofing and water repellency required in
severe weather conditions; while it also has stretchability, durability and a
sensitive soft touch that make it suitable for sportswear.
Corpo Nove, through their R&D spin-off Grado Zero
Espace, has used Thermal Shape Memory metals as a fabric for the manufacturing
of a shirt with long sleeves. The sleeves can be programmed to shorten
immediately as the room temperature becomes a few degrees hotter. The fabric
can be screwed up into a hard ball, pleated and creased then, just by a flux of
hot air (even a hairdryer) pop back automatically to its former shape.
a)
Aerogels
The aero gel
insulation blanket produced by Aspen Aerogels in the U.S. is being employed as
a lining for extreme winter clothing, and is said to be three times more
effective than 3M's Thinsulate and 39 times more insulating than the best
fiberglass insulation. Aerogels are produced through the creation of gelatinous
structures and then removal of all liquid without allowing any shrinkage. It is
therefore packed with microscopic insulative air pockets of silica, alumina,
carbon or other such materials with diameters of less than 100 nanometers that
make it impossible for most gas molecules, including air, to pass through,
resulting in virtually zero heat loss. A wafer thin layer is sufficient
to protect a hand from a blowtorch. A block the size of a person weighs less
than a kilogram and yet can support a small car. Aerogels were used as
insulation on the rover vehicle of the Mars Pathfinder.
b)
Nettle
fibers
Textiles made of
nettle fibers are naturally insulating. The fibers of the stinging nettle have
a special characteristic in the fact that they are hollow which means they can
accumulate air inside thus creating a natural insulation. To create a cool
fabric for summer, the yarn lengths are highly twisted closing the hollow core
and reducing insulation. For winter fabrics, yarns with a low twist are used.
The hollow core of the fibers remains open maintaining a constant temperature.
Conductive Materials
Conductive fabrics combine the breathing/ moisture managing
finishes with high metallic content in textiles. With the addition of nickel,
copper and silver coatings of varying thickness, these fibers provide a
versatile combination of physical and electrical properties for a variety of
applications. For example, the thermal conductivity of fabric is increased a
thousand-fold after the fibers are metallized. Clothing constructed with
conventional polymers have minimal thermal insulation.
Another type of conductive fiber is carbon. ECT (Electric
Conductive Textile) is a carbonized glass fiber textile, each filament of which
is coated with a few nanometers of carbon. The textile can be woven, braided or
knitted with any kind of glass fiber and any kind of yarn. The carbon creates
the electrical conductivity and therefore electrical resistance. This
electrical resistance presents the opportunity to use the textile as an
electric heating medium. Heat is distributed evenly over the entire surface of
the textile with resistance varying between 10 and 3000 Ohm per square of
surface area. However, whether the square is 1 cm2 or 1 m2 in dimension, the
resistance per square is constant. The applied power can be up to 600 Volts (AC
or DC). The combination of both parameters allows ECT to generate an energy
output of between 50 and 10,000 Watt/m2.