Increased
Flexibility in Polyimide Aerogels Using
Aliphatic Spacers in the Polymer Backbone
Marcos Pantoja
Nicholas Boynton
Kevin A. Cavicchi
Bushara Dosa
Jessica L. Cashman
Mary Ann B. Meador
10.1021/acsami.8b20420.s001
https://acs.figshare.com/articles/journal_contribution/Increased_Flexibility_in_Polyimide_Aerogels_Using_Aliphatic_Spacers_in_the_Polymer_Backbone/7757156
Polyimide aerogels
are mechanically strong porous solids with high
surface area, low density, and dielectric constants close to 1, making
them ideal materials for use as substrates for lightweight antennas.
Increasing the flexibility of the polyimide aerogels extends the usefulness
for conformal antennas for use on small aircraft such as unmanned
air vehicles or personal air mobility vehicles. To this end, polyimide
aerogels made with aromatic amines with 4–10 methylene units
as flexible spacers between aromatic rings in the backbone have been
fabricated. Substituting 25–75 mol % of fully aromatic 2,2′-dimethylbenzidine
with these flexible diamines increases the flexibility of polyimide
aerogels, making them bendable at thicknesses up to 2–3 mm.
The density, dielectric constants, thermal and moisture stability,
and mechanical properties of these aerogels were assessed to understand
the effect of the amount and length of the methylene spacers on these
properties.
2019-02-22 15:36:44
flexibility
polyimide aerogels
dielectric constants
methylene
Polymer Backbone Polyimide aerogels
antenna
air mobility vehicles
density
spacer