Fabrication of porous PDMS sponges using spontaneously self-removing sacrificial templates

Poly(dimethylsiloxane) (PDMS) sponges are an emergent technology, garnering much attention in recent years due to their unique mechanical properties, high surface area and hydrophobicity/oleophilicity. In this work, a hydroscopic calcium chloride hard template is used to prepare a PDMS sponge in 6 h, faster than previously reported template removal methods. Furthermore, the unique deliquescent properties of the calcium chloride are harnessed to provide a spontaneously self-removing sacrificial template within 4 days. The resultant PDMS sponges displayed excellent mechanical robustness, exhibiting maximum tensile and compressive stress values of 110 +/- 20 kPa and 2.8 +/- 0.1 MPa, respectively.

Automated summary

PDMS sponges with unique mechanical properties, high surface area and hydrophobic/oleophilic properties have gained much attention. In this study, a hydroscopic calcium chloride hard template was used to prepare PDMS sponges faster than previous methods. The deliquescent properties of calcium chloride were harnessed to provide a self-removing sacrificial template. The resultant PDMS sponges exhibited excellent mechanical robustness.