3D Printing Amorphous Polysiloxane Terpolymers via Vat Photopolymerization

Abstract

Photocuring and vat photopolymerization (VP) additive manufacturing (AM) is reported for two families of fully amorphous poly(dimethyl siloxane) (PDMS) terpolymers containing either diphenylsiloxy (DiPhS) or diethylsiloxy (DiEtS) repeating units. A thiol‐functionalized PDMS crosslinker enables rapid crosslinking in air using efficient thiol–ene addition. Differential scanning calorimetry and dynamic mechanical analysis (DMA) confirm the absence of crystallinity for the DiPhS‐containing systems, while DMA shows a rubbery plateau extending to greater than 200 °C for the DiEtS‐containing system. VP‐AM of both photopolymer systems afford well‐defined 3D geometries, including high aspect ratio structures, which demonstrate feasibility of these photopolymers for the 3D printing of unique geometric objects that require elastomeric performance to temperatures as low as −120 °C.

Rapid High-Resolution Visible Light 3D Printing

“…3D printing soft and extensible objects remain an active area of research due to the challenges that arise from their natural tendency to deform during prints. 44 − 47 A resin comprising 2-hydroxyethyl acrylate monomer with a correspondingly low polymer T g (≈−15 °C) and a small amount of cross-linker, tetra(ethylene glycol) diacrylate (0.1 wt % relative to monomer), was formulated to provide a softer and more extensible material. With the optimized red light photosystem, dogbones were 3D printed with the new soft resin formulation.…”

Fabrication and Functionalization of 3D Printed Polydimethylsiloxane‐Based Microfluidic Devices Obtained through Digital Light Processing

“…Under these conditions, the most frequently used photoinitiators for 3D printing applications are phosphine oxide‐based compounds (TPO and BAPO). [ 45–47 ] These photoinitiators have been reported in the literature for silicone‐based formulations, [ 41,42,48 ] however they do not mix well in the TRAD oligomer. Therefore, we selected a phosphine‐oxide derivate photoinitiator specifically synthesized for this approach (BAPO‐Si, Figure S1, Supporting Information).…”

“…obtained 3D printed dental objects with fascinating antibacterial properties by loading quaternary ammonium salts as antimicrobial agents in a thiol‐ene‐acrylate resin. [ 40 ] Recently, using poly(dimethylsiloxane)‐based photopolymers, well‐defined 3D objects were obtained via thiol‐ene crosslinking chemistry through a customized top‐down 3D printer, [ 41 ] while in a pioneering work, Folch and co‐workers used methacrylate PDMS formulations to produce optically transparent structures and microfluidic channels using a commercial desktop‐SL 3D printer. [ 42 ]…”

Polysiloxanes Modified by Thiol‐Ene Reaction and Their Interaction with Gold Nanoparticles

“…It has been used notably for preparing hydrophilic or amphiphilic polysiloxanes, surface functionalized PDMS elastomers, antibacterial silicones, elastomers for modulating cell adhesion, self‐healing polysiloxanes, polysiloxane elastomers with optical properties, liquid crystal polysiloxanes, electroactive ferrocene‐grafted polysiloxanes, polysiloxanes with tunable dielectric properties, or contact lens elastomers . Thiol‐ene strategy is also used in the case of polysiloxanes for getting an efficient, orthogonal cross‐linking, often initiated photochemically and consequently, has been adapted to electrospinning and 3D printing …”

“…[48] Thiol-ene strategy is also used in the case of polysiloxanes for getting an efficient, orthogonal cross-linking, [18,49 -51] often initiated photochemically and consequently, has been adapted to electrospinning [52] and 3D printing. [53][54][55] In this work, the functionalized polysiloxanes have been prepared in two steps: the first step consisted in preparing poly(methylvinyl-co-dimethyl)siloxanes containing around 25 % of vinyl groups, by cationic redistribution (Scheme 1). In the second step, three different thiols N-methyl-2-sulfanylacetamide (4), 2phenylethane-1-thiol (5) and 3,3,4,4,5,5,6,6,7,7,8,8,9,9,-10,10,10-heptadecafluorodecane-1-thiol (6; Scheme 1) were grafted by thiol-ene reaction on the vinyl polysiloxane.…”