3D printed hydrogel network regulation based on macroinitiator-induced rapid photoATRP

Abstract

Although 3D printing can easily control the macroscopic structure of printed subjects based on digital modeling, the control of the micro-structure of a polymer network is still a challenge. Herein, we report the use of macroinitiator-induced rapid photoATRP to regulate a 3D printed hydrogel network. This approach consists of synthesizing the macroinitiator through CD-catalyzed photoATRP and photocuring in the same pot by the subsequent addition of a crosslinker. By varying the chain length of the macroinitiator, we demonstrated the effect of physical entanglements on the formation of the hydrogel, as well as on its mechanical properties and swelling ratio. All 3D printed objects with different macroinitiators exhibited outstanding print resolution. With a PNIPAM macroinitiator, the printed hydrogel shows the characteristics of a temperature-sensitive response. Overall, the findings of this work enable an interesting platform for control over the mechanical properties and functions of a 3D printed hydrogel.