High‐Speed 3D Printing of High‐Performance Thermosetting Polymers via Two‐Stage Curing

Abstract

Design and direct fabrication of high-performance thermosets and composites via 3D printing are highly desirable in engineering applications. Most 3D printed thermosetting polymers to date suffer from poor mechanical properties and low printing speed. Here, a novel ink for high-speed 3D printing of high-performance epoxy thermosets via a two-stage curing approach is presented. The ink containing photocurable resin and thermally curable epoxy resin is used for the digital light processing (DLP) 3D printing. After printing, the part is thermally cured at elevated temperature to yield an interpenetrating polymer network epoxy composite, whose mechanical properties are comparable to engineering epoxy. The printing speed is accelerated by the continuous liquid interface production assisted DLP 3D printing method, achieving a printing speed as high as 216 mm h . It is also demonstrated that 3D printing structural electronics can be achieved by combining the 3D printed epoxy composites with infilled silver ink in the hollow channels. The new 3D printing method via two-stage curing combines the attributes of outstanding printing speed, high resolution, low volume shrinkage, and excellent mechanical properties, and provides a new avenue to fabricate 3D thermosetting composites with excellent mechanical properties and high efficiency toward high-performance and functional applications.

Development of epoxy‐cyanate ester‐clay nanocomposites offering enhanced thermally stability

“…Many of the aforementioned high‐performance resins and their formulations were not been effectively utilized during the past have now become feasible for making unique, specific, and customized components …”

Dynamic Photomask‐Assisted Direct Ink Writing Multimaterial for Multilevel Triboelectric Nanogenerator

“…The schematic illustration of the two‐stage polymerization process of this ink is shown in Figure c. The acrylate monomers were cured by photoinduced free radical polymerization, and the epoxy resin was thermally cured via organic‐base catalyzed ring‐opening polymerization . As these two kinds of components were polymerized through different mechanisms individually, the two cross‐linked networks were locked together noncovalently to form a so‐called IPN …”

Advances in 4D Printing: Materials and Applications

“…Chen et al used UV‐assisted DIW to print an interpenetrating epoxy resin with a tunable T g and modulus via a two‐stage curing for SMPs. This kind of two‐stage cured epoxy thermoset can be potentially used for high‐ T g SMPs . Yang et al reported the 3D printing of photoresponsive SM devices by combining FFF printing technology and photothermal effect of carbon black–reinforced polyurethane (PU), where sunlight can be used to trigger the SM behavior of 3D printed devices.…”

“…High‐resolution (micro‐ and nanoscale) DLP can be achieved with optical lens systems (called projection microstereolithography (PµSL)) . In addition, a two‐stage curing approach has been combined with DLP to make engineering polymers . Moreover, multimaterial DLP is also gaining some progress using switchable vats or grayscale light …”