Flexible Polyisocyanate Based Aerogels

Abstract

Highly flexible, durable aerogels with textile feel were developed at Aspen Aerogels Inc. by sol-gel chemistry and supercritical CO₂ solvent extraction. These polyisocyanate-based aerogels reinforced with battings showed little to no brittle fracture with repeated flexing. The crosslinker, the isocyanate content and functionality played an important role on properties such as thermal conductivity, durability and flexural modulus at ambient and cryogenic temperatures. The polyisocyanate aerogels crosslinked with polyamine showed thermal conductivities as low as 18 mW/m-K at ambient pressure and those crosslinked with polyol had low flexural modulus at cryogenic temperatures. Applications of these aerogels in aerospace and diving are presented.