Preparation and Performance Study of Highly Elastic Three-Dimensional Porous PDMS Sponge via Direct Ink Writing

Highly elastic porous sponges exhibit tremendous application potential in various fields due to their adjustable characteristics. However, the liquid nature of silicone precursors presents challenges in the fabrication of three-dimensional (3D) structures. In this study, highly elastic three-dimensional porous polydimethylsiloxane (PDMS) sponges were successfully fabricated using a zero-pollution, cost-effective direct ink writing (DIW) technique, combined with NaCl template leaching. The resulting sponges exhibit remarkable supercompressibility, with negligible stress loss (approaching zero) under 80% cyclic compression, outstanding cyclic durability, and exceptional superhydrophobicity, as evidenced by a static contact angle of 164.4°. Furthermore, they demonstrate the ability to selectively adsorb oil slicks on water surfaces and heavy oils submerged underwater, with the added benefit of being reusable. This study demonstrates that the integration of direct ink writing and salt template leaching offers an effective strategy for fabricating highly complex, three-dimensional porous PDMS sponges, enabling the tailored design of highly elastic structural materials.