3D Printed Multifunctional, Hyperelastic Silicone Rubber Foam

Abstract

Highly elastic silicone foams, especially those with tunable properties and multifunctionality, are of great interest in numerous fields. However, the liquid nature of silicone precursors and the complicated foaming process hinder the realization of its three-dimensional (3D) printability. Herein, a series of silicone foams with outstanding performance with regards to elasticity, wetting and sensing properties, multifunctionality, and tunability is generated by direct ink writing. Viscoelastic inks are achieved from direct dispersion of sodium chloride in a unique silicone precursor solution. The 3D-architectured silicone rubber exhibits open-celled trimodal porosity, which offers ultraelasticity with hyper compressibility/cycling endurance (near-zero stress/strain loss under 90% compression or 1000 compression cycles), excellent stretchability (210% strain), and superhydrophobicity. The resulting foam is demonstrated to be multifunctional, such that it can work as an oil sorbent with super capacity (1320%) and customizable soft sensor after absorption of carbon nanotubes on the foam surface. The strategy enables tunability of mechanical strength, elasticity, stretchability, and absorbing capacity, while printing different materials together offers property gradients as an extra dimension of tunability. The first 3D printed silicone foam, which serves an important step toward its application expansion, is achieved.

3D Printed Silicones with Shape Morphing and Low-Temperature Ultraelasticity

“…The energy loss coefficient was defined as the dissipated energy during the compressive cycle relative to the work done by compression, i.e., (W l − W u )/W l , where W l and W u are the area under the loading and unloading stress−strain curve, respectively. As illustrated in Figure 4A, lower inset, the strain loss was as low as around 5.5%, almost independent of the applied strain (in the range of 50%− 85%) and comparable to that of previously reported ultraelastic foams, 6,38 whereas the energy loss coefficient increased from 22% to 31% as the strain increased from 50% to 85%. These results further demonstrate the ultraelasticity and dissipation performance of the foam at room temperature.…”

Printability and mechanical performance of biomedical PDMS-PEEK composites developed for material extrusion

“…9 b) with J-shape curves observed in compression (Fig. 9 c), similar to other PDMS-based materials [13,64]. The tensile modulus was 0.60±0.1 MPa for PDMS, increasing by 3% (PDMS-PEEK10%), 150% (PDMS-PEEK20%) and 113% (PDMS-PEEK30%) (Fig.…”

Strengthening Effect of Flooding in 3d Printed Porous Soft Robotics Scaffolds

“…A similar bending motion was observed, except that the strengthening effect was not examined. Moreover, Chen et al created a spongelike structure from hyperelastic silicone foam to enhance the capacity of volume change [51]. Their compression ratio is similar to our gyroid-shaped model and proofs its validity.…”