3D Printing of High Viscosity Reinforced Silicone Elastomers

Polymers

James P. Lewicki¹  Eric B. Duoss¹  Nicholas Rodriguez¹  Bryan Moran¹  Nikola Dudukovic¹  Josh DeOtte¹  Jean-Baptiste Forien²  James S. Oakdale²  Samantha Ruelas²  Jennifer Rodriguez² 

[1] Materials Engineering Division, Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA 94550, USA;Materials Science Division, Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA 94550, USA;

关键词: stereolithography;    3D printing;    silicone;    elastomer;    MQ resin;    thiol-ene;   

DOI  :  10.3390/polym13142239

来源: DOAJ

【 摘 要 】

Recent advances in additive manufacturing, specifically direct ink writing (DIW) and ink-jetting, have enabled the production of elastomeric silicone parts with deterministic control over the structure, shape, and mechanical properties. These new technologies offer rapid prototyping advantages and find applications in various fields, including biomedical devices, prosthetics, metamaterials, and soft robotics. Stereolithography (SLA) is a complementary approach with the ability to print with finer features and potentially higher throughput. However, all high-performance silicone elastomers are composites of polysiloxane networks reinforced with particulate filler, and consequently, silicone resins tend to have high viscosities (gel- or paste-like), which complicates or completely inhibits the layer-by-layer recoating process central to most SLA technologies. Herein, the design and build of a digital light projection SLA printer suitable for handling high-viscosity resins is demonstrated. Further, a series of UV-curable silicone resins with thiol-ene crosslinking and reinforced by a combination of fumed silica and MQ resins are also described. The resulting silicone elastomers are shown to have tunable mechanical properties, with 100–350% elongation and ultimate tensile strength from 1 to 2.5 MPa. Three-dimensional printed features of 0.4 mm were achieved, and complexity is demonstrated by octet-truss lattices that display negative stiffness.

【 授权许可】

Unknown