Facile Synthesis and 3D Printing of Soft Materials and Their Applications in Sensors

Ion conductive polymers and elastomers have drawn worldwide attention for their multifuntional applicability in batteries, electroactive soft robotics, and sensors. In this work, facile synthesis of network polymers via thiol-ene reaction has been focused on to create 3D printable flexible and soft sensing materials. A variety of materials such as ionic gels, ionic porous polymers, elastomers, and composites have been synthesized and characterized. To develop ionic liquid-based gels and porous polymers, ionic liquid has been incorporated into the thiol–ene network of thiol-based multifunctional monomers and acrylate crosslinkers. By carefully selecting the polymerizing conditions and solvents, developing gel and/or porous polymers are designed. In addition to ionic liquid-based gels and porous polymers, PDMS-based polymers, gels, and elastomers are also synthesized using multi-functional vinyl sulfones and dual functional thiol containing PDMS crosslinkers initiated via thiol-ene reaction mechanism. The developed gels and elastomeric materials showed 3D printability with good resolution with tunable conductivity (ionic gels and porous polymers), mechanical flexibility, and high thermal stability and showed piezo-capacitive sensing characteristics. These 3D-printable, designable materials can find prospective scope in the fields of MEMS, microfluidics, and sensors.