Polyimide Aerogels Using Triisocyanate as Cross-linker

5 years ago

Polyimide Aerogels Using Triisocyanate as Cross-linker

Linda McCorkle, Daniel Scheiman, Baochau N. Nguyen, Mary Ann B. Meador

A family of polyimide (PI)-based aerogels is produced using Desmodur N3300A, an inexpensive triisocyanate, as the cross-linker. The aerogels are prepared by cross-linking amine end-capped polyimide oligomers with the triisocyanate. The polyimide oligomers are formulated using 2,2′-dimethylbenzidine, 4,4′-oxydianiline, or mixtures of both diamines, combined with 3,3′,4,4′-biphenyltetracarboxylic dianhydride, and are chemically imidized at room temperature. Depending on the backbone chemistry, chain length, and polymer concentration, density of the aerogels ranged from 0.06 to 0.14 g/cm³ and Brunauer–Emmett–Teller surface areas ranged from 350 to 600 m²/g. Compressive moduli of these aerogels were as high as 225 MPa, which are comparable to, or higher than, those previously reported prepared with similar backbone structures but with other cross-linkers. Because of their lower cost and commercial availability as cross-linker, the aerogels may have further potential as insulation for building and construction, clothing, sporting goods, and automotive applications, although lower-temperature stability may limit their use in some aerospace applications.

Publisher URL: http://dx.doi.org/10.1021/acsami.7b07821

DOI: 10.1021/acsami.7b07821