Available for service temperatures from –460° to 1200°F, aerogels are suited for low-, high-, and dual-temperature insulation applications.
Aerogels from Aspen Aerogels Inc.
(Northborough, MA, U.S.; www.aerogel.com) feature an ultrathin profile
and extremely low thermal conductivity, enabling appliance designers to
insulate in tighter and smaller profiles. They also provide reduced
condensation in critical areas of freezers, making it easier for
appliances to achieve Energy Star ratings. Aerogels are now available
from Pacor Inc. (Bordentown, NJ, U.S.; www.pacorinc.com) and its wholly
owned subsidiary LIT Industries Inc. (Gastonia, NC, U.S.;
www.litnc.com). Partnering with Aspen Aerogels Inc., they distribute
and fabricate insulation materials made from nanoporous aerogels to
meet customer specifications.
makers, like most equipment manufacturers, are constantly striving to
make their products more efficient and environmentally friendly,” says
Joe Posda, product manager–Aerogels at Pacor Inc. “Aerogels are two to
eight times more efficient than traditional insulation materials, so
much less material is needed to achieve the same thermal results.”
Besides their low thermal conductivity, “aerogels have the lowest
embodied energy and lowest embodied CO2 of any insulation material.
This, combined with energy efficiency, has allowed aerogels to obtain a
silver level cradle-to-cradle certification.” Aerogels are also
landfill disposable and contain no respirable fiber, he adds.
says the aerogels’ composition is key to their ultrathin profile, light
weight, and low thermal conductivity. “Aerogels consist of lightweight
silica solids derived from a gel in which the liquid component has been
replaced with gas. The silica solids, which are poor conductors,
consist of very small, 3-D, intertwined clusters and comprise only 3%
of the volume. Conduction through the solid is therefore very low,”
Posda explains. “The remaining 97% of the volume is composed of air
trapped in extremely small nanopores. The air has little room to move,
so it inhibits both convection and gas phase conduction.” Because of
the thermal stability, Posda says, there is no degradation of thermal
values over time as compared with polyurethane foams.
qualities also give aerogels resistance to flame spread and smoke
emission. “In hydrocarbon fires, for example, they protect piping and
equipment longer. This is critical to increasing the reaction time
needed to respond to a catastrophic event,” Posda tells APPLIANCE.
“Aerogels are hydrophobic through the entire matrix of the material and
not just on the surface, so they provide excellent resistance to
moisture. Other insulations tend to absorb moisture over time,
potentially corroding the substrate.”
aerogels have been in existence for more than 70 years, Posda says, the
technology to manufacture them commercially is relatively new.
“Appliances and commercial cooking equipment have become a viable
application over the last three to four years. As with any new product,
manufacturers have to conduct extensive testing programs in-house,”
Posda says. “Many appliance manufacturers have been testing aerogels
over the last 12–18 months, with several commercial applications now in
Aerogels can be cut, bonded, and
attached in the same way as traditional insulation materials. But
unlike traditional materials, their thin profile increases internal
volume, providing more usable area for the same footprint. Aerogels
also allows engineers to design smaller units that do the same job as
existing products. “They can also engineer a more energy-efficient
appliance with the same insulation thickness,” says Posda.
two aerogel products are available for appliance OEMs. Pyrogel XT is a
high-temperature insulation blanket formed of silica aerogel and
reinforced with a nonwoven, glass-fiber batting. With a maximum use
temperature of 1200°F (650°C), it is available in thicknesses of 5 and
10 mm. Pyrogel XT has a density of 11 lb/cu ft (0.18 g/cm3) and is
hydrophobic. It is suited for stove range tops, oven wall cavities, hot
water heaters, and commercial cooking equipment.
Z is a flexible aerogel insulation blanket engineered to deliver
maximum thermal protection with minimal weight and thickness and zero
water vapor permeability. Also available in thicknesses of 5 and 10 mm,
Cryogel Z has a maximum use temperature of 194°F (90°C). It’s also
hydrophobic, with a density of 8.0 lb/cu ft (0.13 g/cm3). Cryogel Z’s
properties make it attractive for manufacturers seeking maximum thermal
protection in cryogenic cold applications, such as refrigerators, and
With plants in New Jersey,
North Carolina, and Georgia, Pacor and LIT Industries fabricate
aerogels by die-cutting, laminating, CNC cutting, encapsulating, and
close-tolerance slitting and sheeting. Application of
pressure-sensitive adhesives can also be performed.