Donghao Zhao: State Key Laboratory of Fluid Power & Mechatronic System, Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province, Center for X-Mechanics, Department of Engineering Mechanics, Zhejiang University, Hangzhou 310027, China.
Yide Liu: State Key Laboratory of Fluid Power & Mechatronic System, Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province, Center for X-Mechanics, Department of Engineering Mechanics, Zhejiang University, Hangzhou 310027, China.
Binhong Liu: State Key Laboratory of Fluid Power & Mechatronic System, Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province, Center for X-Mechanics, Department of Engineering Mechanics, Zhejiang University, Hangzhou 310027, China.
Zhe Chen: State Key Laboratory of Fluid Power & Mechatronic System, Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province, Center for X-Mechanics, Department of Engineering Mechanics, Zhejiang University, Hangzhou 310027, China.
Guodong Nian: State Key Laboratory of Fluid Power & Mechatronic System, Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province, Center for X-Mechanics, Department of Engineering Mechanics, Zhejiang University, Hangzhou 310027, China. ORCID
Shaoxing Qu: State Key Laboratory of Fluid Power & Mechatronic System, Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province, Center for X-Mechanics, Department of Engineering Mechanics, Zhejiang University, Hangzhou 310027, China. ORCID
Wei Yang: State Key Laboratory of Fluid Power & Mechatronic System, Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province, Center for X-Mechanics, Department of Engineering Mechanics, Zhejiang University, Hangzhou 310027, China.
3D printing of hydrogels finds widespread applications in biomedicine and engineering. Artificial cartilages and heart valves, tissue regeneration and soft robots, require high mechanical performance of complex structures. Although many tough hydrogels have been developed, complicated synthesis processes hinder their fabrication in 3D printing. Here, a strategy is proposed to formulate hydrogel inks, which can be printed into various strong and tough particle-based double-network (P-DN) hydrogels of arbitrary shapes without any rheological modifiers. These hydrogel inks consist of microgels and a hydrogel precursor. The microgels are individual highly cross-linked networks. They are prepared by swelling dried microparticles in the hydrogel precursor that consists of monomers, initiators, and cross-linkers. Microgels regulate the rheological properties of the hydrogel ink and enable the direct printing. After printing and curing, the precursor forms a sparsely cross-linked network that integrates the microgels, leading to a P-DN hydrogel. The proposed hydrogel inks allow 3D printing of multifunctional hydrogel structures with high mechanical performance and strong adhesion to diverse materials. This strategy will open new avenues to fabricate multifunctional devices in tissue engineering and soft robotics.
