Scalable, hydrophobic and highly-stretchable poly(isocyanurate–urethane) aerogels. Issue 38 (8th June 2018)

• Record Type: Journal Article
• Authors: Malakooti, Sadeq; Rostami, Saman; Churu, Habel Gitogo; Luo, Huiyang; Clark, Jenna; Casarez, Fabiola; Rettenmaier, Owen; Daryadel, Soheil; Minary-Jolandan, Majid; Sotiriou-Leventis, Chariklia; Leventis, Nicholas; Lu, Hongbing
• Is Part Of: RSC advances. Volume 8:Issue 38(2018)
• Page Start: 21214
• Page End: 21223
• Publication Date: 2018-06-08
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c8ra03085e
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : Scalable, low-density and flexible aerogels offer a unique combination of excellent mechanical properties and scalable manufacturability. Abstract : Scalable, low-density and flexible aerogels offer a unique combination of excellent mechanical properties and scalable manufacturability. Herein, we report the fabrication of a family of low-density, ambient-dried and hydrophobic poly(isocyanurate–urethane) aerogels derived from a triisocyanate precursor. The bulk densities ranged from 0.28 to 0.37 g cm −3 with porosities above 70% v/v. The aerogels exhibit a highly stretchable behavior with a rapid increase in the Young's modulus with bulk density (slope of log–log plot > 6.0). In addition, the aerogels are very compressible (more than 80% compressive strain) with high shape recovery rate (more than 80% recovery in 30 s). Under tension even at high strains ( e.g., more than 100% tensile strain), the aerogels at lower densities do not display a significant lateral contraction and have a Poisson's ratio of only 0.22. Under dynamic conditions, the properties ( e.g., complex moduli and dynamic stress–strain curves) are highly frequency- and rate-dependent, particularly in the Hopkinson pressure bar experiment where in comparison with quasi-static compression results, the properties such as mechanical strength were three orders of magnitude stiffer. The attained outcome of this work supports a basis on the understanding of the fundamental mechanical behavior of a scalable organic aerogel with potential in engineering applications including damping, energy absorption, and substrates for flexible devices.