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Novel superflexible resorcinol–formaldehyde aerogels and combining of them with aramid honeycombs

Published online by Cambridge University Press:  11 November 2014

Marina Schwan*
Affiliation:
Institute of Materials Research, German Aerospace Center, DLR, 51170 Cologne, Germany
Barbara Milow
Affiliation:
Institute of Materials Research, German Aerospace Center, DLR, 51170 Cologne, Germany
Lorenz Ratke
Affiliation:
Institute of Materials Research, German Aerospace Center, DLR, 51170 Cologne, Germany
*
Address all correspondence to Marina Schwan at [email protected]
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Abstract

We report a new insulation composite of aramid honeycombs filled with superflexible resorcinol–formaldehyde aerogels. Aerogels produced via a sol–gel process were dried with supercritical CO2. The aerogels exhibit a high, rubber-like flexibility, due to almost zero shrinkage and networking of nanoparticles and suitably sized macropores. The high porosity of the aerogels in the range of about 95–98% leads to a low thermal conductivity about 0.037 W/mK and low bulk density of 0.05 g/cm3. The filling of light and stiff aramid honeycombs with these flexible aerogels results in a composite with decreased thermal conductivity and modified mechanical properties.

Type
Research Letters
Copyright
Copyright © Materials Research Society 2014 

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