Exceptionally strong polyimide aerogels that are up to 500 times stronger than conventional aerogels have been developed by NASA�s Glenn Research Center. These cross-linked polyimide aerogels are lightweight and porous, with low thermal conductivity, making them an ideal material for numerous automotive applications. They can be formed into monoliths or thin films for use in acoustic and thermal insulation (e.g., engine firewall), vibration damping, thin-film coatings, or anywhere structural foam is currently used in vehicles.
• Mechanically strong: upto 500 times stronger than conventional aerogels
• Versatile: Can be custom manufactured as monoliths and thin films
• Low thermal conductivity: R values range from 2 to 10 times higher than polymer foams in line with silica aerogels of the same density
• Very lightweight: Materials are up to 95% porous
• Streamlined manufacturing process
• Thermal insulation
• Acoustic insulation for motor vehicle passenger compartments
• Vibration damping materials
• Ballistic impact absorbing materials
• Hose insulation
• Catalytic supports
• Dielectrics for fast electronics
• Optical sensor supports
• Automotive components
• Structural components in layered or sandwich-type composites
The polyimide aerogels are cross-linked through use of octa(aminophenyl)silsesquioxane (OAPS). Gels formed from polyamic acid solutions and OAPS are chemically imidized and dried using supercritical CO2 extraction to create aerogels with densities from 0.08 to 0.2 g/cm3. Drying the gels super critically maintains the solid structure of the gel, creating a polyimide aerogel with improved mechanical properties over other aerogels. Notably, the polyimide aerogels cross-linked with OAPS have higher modulus than even polymer-reinforced silica aerogels of similar density and can be fabricated as both monoliths and thin films. NASA�s polyimide aerogels are 85 to 95% porous, have high surface areas, low shrinkage, and low thermal conductivity. They can withstand temperatures of 300-400�C (as opposed to previous versions that reached 100�C). Because they provide better thermal and acoustic insulation, the overall weight and bulk of the insulation is reduced. This allows for a smaller manufactured product, thus reducing manufacturing costs and other associated expenses. Unlike multilayer insulation, aerogels do not require a high vacuum to maintain their low thermal conductivity and can function as good thermal insulators at ambient pressure. The polyimide aerogels also are excellent vibration-damping materials. Recent work has led to the development of more hydrophobic formulations (important for use in damp environments) and greater temperature stability.
Glenn has filed a patent application for this technology. Glenn�s Office of Technology Partnerships and Planning seeks to transfer technology to and from NASA to benefit the space program and U.S. industry.