Yan Ge, Zhou Mengjie, Zhang Jun, Zhang Wenjie, He Yanjie, Qiao Xiaoguang, Shi Ge, Pang Xinchang
School of Materials Science and Engineering, Henan University of Science and Technology, Luoyang, 471023, P. R. China.
Henan Joint International Research Laboratory of Living Polymerizations and Functional Nanomaterials, Henan Key Laboratory of Advanced Nylon Materials and Application, School of Materials Science and Engineering, Zhengzhou University, Zhengzhou, 450001, P. R. China.
Small. 2025 Jun;21(24):e2411688. doi: 10.1002/smll.202411688. Epub 2025 May 3.
Photocurable 3D printing (SLA or DLP) materials have garnered considerable attention due to their remarkable efficiency and precision in manufacturing. However, the presence of covalent crosslinking makes the recycling and reuse of printed materials extremely challenging. Here a novel approach to covalent crosslinker-free photo-curing 3D printing (via DLP) of liquid metal (LM) composite hydrogels is reported, leveraging surface-initiated photoinduced atom radical transfer polymerization (SI-photoATRP). The pre-synthesized PHEA-Br macroinitiators are grafted onto the surfaces of LM nanoparticles (LMNPs) by mechanical sonication, stabilizing the LMNPs within the resin solution while simultaneously generating active sites for SI-photoATRP. During the SI-photoATRP process, polymer chains of sufficient length form hydrogen bonds with multiple LMNPs, effectively transforming the LMNPs into crosslinking points. By integrating the aqueous photoATRP system catalyzed by carbon dots, LM@polymer composite hydrogel with complex structures are successfully established through DLP technology. The versatility of the 3D printed hydrogel is investigated by employing HEA, OEGA and AAm as the monomers in resin solution, respectively. Notably, all the LM@polymer composite hydrogels can be degraded in aqueous NaOH solution. Furthermore, LM@polymer-based networks exhibit self-repairing capabilities, serve as underwater adhesives, and conduct electricity. This work offers new insights into designing 3D printing materials and sustainable photocurable technology.
光固化3D打印（SLA或DLP）材料因其在制造过程中具有显著的效率和精度而备受关注。然而，共价交联的存在使得打印材料的回收和再利用极具挑战性。本文报道了一种通过表面引发光诱导原子自由基转移聚合（SI-photoATRP）实现无共价交联剂的液态金属（LM）复合水凝胶光固化3D打印（通过DLP）的新方法。通过机械超声将预合成的PHEA-Br大分子引发剂接枝到LM纳米颗粒（LMNPs）表面，使LMNPs在树脂溶液中稳定，同时为SI-photoATRP生成活性位点。在SI-photoATRP过程中，足够长的聚合物链与多个LMNPs形成氢键，有效地将LMNPs转化为交联点。通过整合由碳点催化的水性光ATRP体系，利用DLP技术成功制备了具有复杂结构的LM@聚合物复合水凝胶。分别以HEA、OEGA和AAm作为树脂溶液中的单体，研究了3D打印水凝胶的多功能性。值得注意的是，所有的LM@聚合物复合水凝胶都能在NaOH水溶液中降解。此外，基于LM@聚合物的网络具有自修复能力，可作为水下粘合剂并导电。这项工作为设计3D打印材料和可持续光固化技术提供了新见解。
