Desktop‐Stereolithography 3D‐Printing of a Poly(dimethylsiloxane)‐Based Material with Sylgard‐184 Properties

Abstract

The advantageous physiochemical properties of poly(dimethylsiloxane) (PDMS) have made it an extremely useful material for prototyping in various technological, scientific, and clinical areas. However, PDMS molding is a manual procedure and requires tedious assembly steps, especially for 3D designs, thereby limiting its access and usability. On the other hand, automated digital manufacturing processes such as stereolithography (SL) enable true 3D design and fabrication. Here the formulation, characterization, and SL application of a 3D-printable PDMS resin (3DP-PDMS) based on commercially available PDMS-methacrylate macromers, a high-efficiency photoinitiator and a high-absorbance photosensitizer, is reported. Using a desktop SL-printer, optically transparent submillimeter structures and microfluidic channels are demonstrated. An optimized blend of PDMS-methacrylate macromers is also used to SL-print structures with mechanical properties similar to conventional thermally cured PDMS (Sylgard-184). Furthermore, it is shown that SL-printed 3DP-PDMS substrates can be rendered suitable for mammalian cell culture. The 3DP-PDMS resin enables assembly-free, automated, digital manufacturing of PDMS, which should facilitate the prototyping of devices for microfluidics, organ-on-chip platforms, soft robotics, flexible electronics, and sensors, among others.

Facile Photo and Thermal Two‐Stage Curing for High‐Performance 3D Printing of Poly(Dimethylsiloxane)

“…[ 19 ] Bhattacharjee and co‐workers realized desktop‐stereolithography 3D printing of PDMS based on commercially available methacrylated PDMS. [ 20 ] Very recently, Qin et al developed a methacrylated PDMS that can realize the ultrafast and continuous fabrication of the PDMS membrane by UV induced polymerization. [ 21 ] Despite of the 3D objects obtained in the previous efforts, there are still some blemishes including the difficulty to build complicated 3D architectures and the requirement of fussy procedures for manually removing supporting bath.…”

“…[ 21 ] Despite of the 3D objects obtained in the previous efforts, there are still some blemishes including the difficulty to build complicated 3D architectures and the requirement of fussy procedures for manually removing supporting bath. [ 22 ] Also, most of them are not compatible to the commercially available PDMSs, and moreover these tailor‐made PDMSs for 3D printing usually exhibited quite poor mechanical performances with the tensile strength of less than ≈0.7 MPa, which is one order decrease, [ 6,20 ] and the elastic modulus of less than 0.9 MPa. [ 19 ] Therefore, there are still challenges to achieve 3D printing of PDMS and devices, especially with a universal approach and based on commercial materials.…”

Engineered 3D Polymer and Hydrogel Microenvironments for Cell Culture Applications

“…Combined with in situ UV curing, bioprinting of drug-loaded PDMS via semi-solid extrusion at room temperature was accomplished, with feature sizes of~250 µm [194]. PDMS-methacrylate macromers have been developed for SLA also with feature sizes of~250 µm [195]. For high resolution 3D printing of PDMS, TPP was used to produce 3D structures with submicron resolution [196] by mixing photocurable PDMS with a photoinitiator.…”

“…Biocompatibility, Biodegradability, and Bioactivity SLA fabricated PDMS scaffolds were shown to support cell viability, although the extraction of solvent used during processing is critical in lowering cytotoxicity [195]. Taking advantage of its hydrophobicity, oil-infused PDMS with encapsulated Ag nanoparticles was 3D printed as an anti-bacterial wound dressing [202].…”

“…Feature size 1 mm (SLA) [150]; Feature size 20 µm (TPP) [61] Human fetal osteoblasts [145]; human bone-marrow stromal cells [143]; Schwann cells [61]; osteoconductivity [147,158]; bacterial cell colonies [142] PEEK (4. Feature size 25 µm (SLA) [173]; Feature size 5 µm (TPP) [177][178][179]; Inclusion of silk and melanin, storage E: 1-2.5 kPa [134] Anti-bacterial [183]; hMSCs [174] PDMS (4.2.2) Feature size 250 µm [194] Feature size 250 µm (SLA) [195]; Feature size <1 µm (TPP) [196]; E: 0.4-1.7 MPa [199]; E: 0.05-1 MPa [200] Anti-bacterial [47]…”