3D printing-directed auxetic Kevlar aerogel architectures with multiple functionalization options
3D printing-directed auxetic Kevlar aerogel architectures with multiple functionalization options
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DOI：
10.1039/d0ta02590a
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发表时间：
2020-07-28
影响因子：
11.9
通讯作者：
Song, Wenhui
中科院分区：
文献类型：
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作者：
Cheng, Qingqing;Liu, Yang;Song, Wenhui
具有负泊松比的拉胀结构由于其有趣的物理特性、众多有前景的应用以及制造技术的最新进展而引起了越来越多的关注。然而，制造具有定制的分层多孔结构和所需的物理/机械性能的三维（3D）聚合物拉胀结构仍然具有挑战性。在此，通过一种新的增材制造策略设计和制造了具有多种尺度孔隙率的3D纳米纤维凯夫拉气凝胶结构，即直接墨水书写和冷冻铸造与无毒溶剂型墨水的结合，然后采用特殊的干燥技术。高度多孔的3D纳米纤维Kevlar气凝胶结构具有超低密度（低至11.9 mg cm(-3)）和大比表面积（高达350 m(2)g(-1)）的优异机械性能。通过调整设计的图案支柱的空间布置，泊松比可在-0.8至0.4的宽范围内调节。最后，这些纳米纤维凯夫拉气凝胶结构分别通过使用氟碳树脂、功能染料和有机相变材料进一步功能化为疏水性、发光性和热敏性结构。多功能拉胀气凝胶结构展示了广泛应用的潜力。
Auxetic architectures with a negative Poisson's ratio have attracted increasing attention due to their intriguing physical properties and numerous promising applications and recent advancements in manufacturing techniques. However, fabrication of three-dimensional (3D) polymeric auxetic architectures with a tailored hierarchically porous structure and desired physical/mechanical properties remains challenging. Herein, 3D nanofibrous Kevlar aerogel architectures with porosity at multiple scales have been designed and fabricated through a new additive manufacturing strategy,i.e., integration of direct ink writing and freeze-casting with non-toxic solvent-based inks followed by special drying techniques. The highly porous 3D nanofibrous Kevlar aerogel architectures achieve excellent mechanical properties with an ultralow density (down to 11.9 mg cm(-3)) and large specific surface area (up to 350 m(2)g(-1)). The Poisson's ratio is tunable in a wide range, spanning from -0.8 to 0.4, by adjusting the spatial arrangement of the designed pattern struts. Finally, these nanofibrous Kevlar aerogel architectures have been further functionalized into hydrophobic, luminescent and thermoresponsive architectures by using fluorocarbon resin, functional dyes and organic phase-change materials respectively. The multi-functional auxetic aerogel architectures demonstrate potential for a broad range of applications.