Direct ink writing 3D printing of polydimethylsiloxane-based soft and composite materials: a mini review

Polydimethylsiloxane (PDMS) has been widely used in flexible electronics, biomedical tissue/organ devices, and soft robots. With the rapid advances in three-dimensional (3D) printing technologies, there has been considerable interest in using PDMS to create 3D, high-resolution, and multifunctional structures/devices. Among different 3D printing technologies, direct ink writing (DIW), where PDMS-based ink or gel is extruded from a moving nozzle, has demonstrated advantages of low cost, simplicity, and ability to combine different materials in a single processing step. Here, we provide a critical perspective on the advances and potential of DIW technology for PDMS-based materials. We will summarize the key factors and innovation in the DIW processes. Furthermore, we will also show state-of-the-art structures and applications of DIW printed PDMS-based materials. Finally, we hope to point out specific challenges, areas for further development, and provide guidelines to those interested in PDMS-based DIW.