3D-printable, highly conductive hybrid composites employing chemically-reinforced, complex dimensional fillers and thermoplastic triblock copolymers

Abstract

The use of 3-dimensional (3D) printable conductive materials has gained significant attention for various applications because of their ability to form unconventional geometrical architectures that cannot be realized with traditional 2-dimensional printing techniques. To resolve the major requisites in printed electrodes for practical applications (including high conductivity, 3D printability, excellent adhesion, and low-temperature processability), we have designed a chemically-reinforced multi-dimensional filler system comprising amine-functionalized carbon nanotubes, carboxyl-terminated silver nanoparticles, and Ag flakes, with the incorporation of a thermoplastic polystyrene-polyisoprene-polystyrene (SIS) triblock copolymer. It is demonstrated that both high conductivity, 22 939 S cm, and low-temperature processability, below 80 °C, are achievable with the introduction of chemically anchored carbon-to-metal hybrids and suggested that the highly viscous composite fluids employing the characteristic thermoplastic polymer are readily available for the fabrication of various unconventional electrode structures by a simple dispensing technique. The practical applicability of the 3D-printable highly conductive composite paste is confirmed with the successful fabrication of wireless power transmission modules on substrates with extremely uneven surface morphologies.

Extrusion 3D Printing of Polymeric Materials with Advanced Properties

“…Using a similar strategy, the electrodes based on carbon nanotubes were also printed using a composite ink composed of silver nanoparticles and silver flakes and a thermoplastic polystyrene–polyisoprene–polystyrene (SIS) triblock copolymers. [ 164 ] The thermoplastic polymer was used to enhance shear thinning behavior. The high conductivity of the printed electrodes was easily obtained after post‐treatment at a temperature as low as 80 °C, without additional processing.…”

“…The use of dynamic bonds which undergo reversible breaking, exchange and reformation could be utilized to modify the printability of polymers as well as imparting various advanced functions. [ 41–58,62–67,59,68,60,69,70,72,61,73,71,82,86–88,74–81,83–85,89–133,244,258 , …”

3D-printed origami electronics using percolative conductors

“…The isoprene segment with a glass transition temperature below À60 C can be partially melted even at room temperature, which contributes critically to the formation of the suitably adhesive printed structures. 14 As another characteristic of electrodes printed from composite pastes, they are sustainable in a polar solvent medium, as the SIS tri-block copolymer is soluble only in noncoordinating solvents. As shown in Fig.…”

“…12,13 This can be accomplished if using 3D-printable, extremely foldable, highly conductive electrodes. Recently, we have reported a facile way of formulating 3D-printable, conductive composite paste comprising of silver akes and multi-walled carbon nanotubes decorated with aqueous silver nanoparticles, with a usage of simple dispensing technique; 14 but, an applicability toward 3D-printed origami electronics has not been suggested with a demonstration of foldable electrodes on paper substrates.…”

Selective metallic coating of 3D-printed microstructures on flexible substrates

“…Moreover, recent research has shown the feasibility of applying three-dimensional conductive patterns on electronic applications, such as sensors, electrodes, and wireless devices. [17][18][19] However, it is difficult to achieve both miniaturization and true three-dimensional metallic features. Moreover, rendering the substrate exibility is attracting much research interests.…”