Sustainable and Recyclable Acrylate Resins for Liquid-Crystal\nDisplay 3D Printing Based on Lipoic Acid

The\ndevelopment of renewable vinyl-based photopolymer resins offers\na promising solution to reducing the environmental impact associated\nwith 3D printed materials. This study introduces a bifunctional lipoate\ncross-linker containing a dynamic disulfide bond, which is combined\nwith acrylic monomers (<i>n</i>-butyl acrylate) and conventional\nphotoinitiators to develop photopolymer resins that are compatible\nwith commercial stereolithography 3D printing. The incorporation of\ndisulfide bonds within the polymer network’s backbone imparts\nthe 3D printed objects with self-healing capabilities and complete\ndegradability. Remarkably, the degraded resin can be fully recycled\nand reused for high-resolution reprinting of complex structures while\npreserving mechanical properties that are comparable to the original\nmaterial. This proof-of-concept study not only presents a sustainable\nstrategy for advancing acrylate-based 3D printing materials, but also\nintroduces a novel approach for fabricating fully recyclable 3D-printed\nstructures. This method paves the way for reducing the environmental\nimpact while enhancing material reusability, offering significant\npotential for the development of eco-friendly additive manufacturing.