Digital Light Processing 3D Printing of Tough Supramolecular Hydrogels with Sophisticated Architectures as Impact‐Absorption Elements. Issue 34 (17th July 2022)

• Record Type: Journal Article
• Authors: Dong, Min; Han, Ying; Hao, Xing Peng; Yu, Hai Chao; Yin, Jun; Du, Miao; Zheng, Qiang; Wu, Zi Liang
• Is Part Of: Advanced materials. Volume 34:Issue 34(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-07-17
• Subjects: 3D printing -- Digital Light Processing -- impact‐absorption elements -- pressure sensors -- tough hydrogels; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.202204333
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract: Processing tough hydrogels into sophisticated architectures is crucial for their applications as structural elements. However, Digital Light Processing (DLP) printing of tough hydrogels is challenging because of the low‐speed gelation and toughening process. Described here is a simple yet versatile system suitable for DLP printing to form tough hydrogel architectures. The aqueous precursor consists of commercial photoinitiator, acrylic acid, and zirconium ion (Zr 4+ ), readily forming tough metallo‐supramolecular hydrogel under digital light because of in situ formation of carboxyl–Zr 4+ coordination complexes. The high‐stiffness and antiswelling properties of as‐printed gel enable high‐efficiency printing to form high‐fidelity constructs. Furthermore, swelling‐induced morphing of the gel is also achieved by encoding structure gradients during the printing with grayscale digital light. Mechanical properties of the printed hydrogels are further improved after incubation in water due to the variation of local pH and rearrangement of coordination complex. The swelling‐enhanced stiffness affords the printed hydrogel with shape fixation ability after manual deformations, and thereby provides an additional avenue to form more complex configurations. These printed hydrogels are used to devise an impact‐absorption element or a high‐sensitivity pressure sensor as proof‐of‐concept examples. This work should merit engineering of other tough gels and extend their scope of applications in diverse fields. Abstract : Digital Light Processing 3D printing of hydrogels with the "bottom‐up" projection approach is realized by a fast gelation and toughening process with in situ formation of coordination complexes as the physical crosslinks. The high stiffness and antiswelling properties of as‐printed tough supramolecular hydrogel enable high‐efficiency printing to form sophisticated architectures, favoring the design of hydrogel devices with versatile applications.