Digital Light Processing 3D Printing of Healable and Recyclable Polymers with Tailorable Mechanical Properties

Abstract

Three-dimensional (3D) printing is becoming a revolutionary technique across various fields. Especially, digital light processing (DLP) 3D printing shows advantages of high resolution and high efficiency. However, multifunctional monomers are commonly used to meet the rapid liquid-to-solid transformation during DLP printing, and the extensive production of unreprocessable thermosets will lead to resource waste and environmental problems. Here, we report a family of dynamic polymers with highly tailorable mechanical properties for DLP printing. The dynamic polymers cross-linked by ionic bonding and hydrogen bonding endow printed objects with excellent self-healing and recycling ability. The mechanical properties of printed objects can be easily tailored from soft elastomers to rigid plastics to satisfy practical applications. Taking advantage of the dynamic cross-linking, various assembling categories, including 2D to 3D, small to large 3D structures, and same to different materials assembly, and functional devices with a self-healing capacity can be realized. This study not only helps to address environmental issues caused by traditional DLP-printed thermosets but also realizes the on-demand fabrication of complex structures.

Digital Light Processing 3D Printing of Enhanced Polymers via Interlayer Welding

“…DLP Printing: A commercial DLP-based 3D printing system using a blue laser projector was used to fabricate 3D structures. [42][43][44] All the objects were printed at a light intensity of 10 mW cm −2 , a layer curing time of 10 s and a slice thickness of 50 μm. The printed structures were washed by ethanol to remove the unreacted monomers and then treated under light irradiation (10 mW cm −2 ) for 10 min.…”

Additive manufacturing by digital light processing: a review

“…Zhou et al printed a piezoelectric nanogenerator for self-power sensor application using barium titanate polymer-based composite [167]. Zhu et al mentioned DLP printing of healable and recyclable polymers for various applications [168]. High-resolution printing DLP technology also enables the manufacturing of microfluidic devices [169,170].…”

3D Printing of Solvent-Free Supramolecular Polymers

“…Manufacturing of supramolecular polymers by electrospinning (B), fused deposition modeling (C), material jetting (D), and digital light processing (E). Adapted with permission (Hart et al, 2016;Hochleitner et al, 2018;Rupp et al, 2019;Zhu et al, 2021) activities, which eliminate limitations of the technology and help understanding of fundamental processes (Ngo et al, 2018).…”

“…Manufacturing of supramolecular polymers by electrospinning (B) , fused deposition modeling (C) , material jetting (D) , and digital light processing (E) . Adapted with permission ( Hart et al, 2016 ; Hochleitner et al, 2018 ; Rupp et al, 2019 ; Zhu et al, 2021 ). Copyright 2018, John Wiley and Sons.…”

“…Within an appropriately designed copolymer, the poly(urethane methacrylate) part acts as a soft polymer featuring hydrogen bonds, with the poly(acrylic acid) part representing the rigid phase. In addition to the supramolecular interactions, ionic interactions of zinc dimethacrylate were used as crosslinker during light curing of this polymer ( Kuang et al, 2018 ; Zhu et al, 2021 ). Invernizzi et al (2018 ) developed a self-healing and shape-memory material based on PCL and UPy being co-crosslinked via methacrylate units.…”