The hydrophobilization of aerogels is critical for their long‐term application due to their highly open‐porous structures, while the hydrophobilization strategies for polyimide (PI) aerogels are limited. In the present work, a feasible strategy to synthesize superhydrophobic PI aerogels is proposed via a conformal‐coating process. The resulting PI aerogels (F‐PI) exhibit high contact angles up to 156°. Impressively, the F‐PI aerogels show excellent water‐resistant capacity not only in the ambient condition but also in the high‐pressure water up to 0.5 MPa, where the liquid cannot or only partially permeate into the aerogel's open pores. Besides, the F‐PI aerogels possess high Brunauer–Emmett–Teller surfaces areas (185 m² g⁻¹), high Young's modulus (3 MPa), low thermal conductivity (0.056 W m⁻¹·k⁻¹), and variable densities. All these parameters are found to be well preserved after high pressure (0.1–0.2 MPa) water treatment, further indicating the excellent water‐resistant performance of the F‐PI aerogels. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48849.

中文翻译：

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通过保形涂层策略的超疏水聚酰亚胺气凝胶具有出色的水下性能

气凝胶的疏水化由于其高度开放的结构而对于其长期应用至关重要，而聚酰亚胺（PI）气凝胶的疏水化策略是有限的。在目前的工作中，通过保形涂层工艺提出了一种合成超疏水PI气凝胶的可行策略。所得的PI气凝胶（F‐PI）表现出高达156°的高接触角。令人印象深刻的是，F-PI气凝胶不仅在环境条件下，而且在高达0.5 MPa的高压水中均表现出出色的耐水性，在这种情况下，液体无法或仅部分渗透到气凝胶的开孔中。此外，F-PI气凝胶具有较高的Brunauer-Emmett-Teller表面面积（185 m ² g ^-1），高杨氏模量（3 MPa），低导热率（0.056 W m ^-1 ·k ^-1）和可变密度。发现所有这些参数在高压（0.1-0.2 MPa）水处理后都能很好地保存，这进一步表明了F-PI气凝胶的出色防水性能。分级为4 +©2019 Wiley Periodicals，Inc.J.Appl。Polym。科学 2020，137，48849。