3D-Printed Conductive Carbon-Infused Thermoplastic Polyurethane

Abstract

3D printable, flexible, and conductive composites are prepared by incorporating a thermoplastic elastomer and electrically conductive carbon fillers. The advantageous printability, workability, chemical resistance, electrical conductivity, and biocompatibility components allowed for an enabling of 3D-printed electronics, electromagnetic interference (EMI) shielding, static elimination, and biomedical sensors. Carbon-infused thermoplastic polyurethane (C/TPU) composites have been demonstrated to possess right-strained sensing abilities and are the candidate in fields such as smart textiles and biomedical sensing. Flexible and conductive composites were prepared by a mechanical blending of biocompatible TPU and carbons. 3D structures that exhibit mechanical flexibility and electric conductivity were successfully printed. Three different types of C/TPU composites, carbon nanotube (CNT), carbon black (CCB), and graphite (G) were prepared with differentiating sizes and composition of filaments. The conductivity of TPU/CNT and TPU/CCB composite filaments increased rapidly when the loading amount of carbon fillers exceeded the filtration threshold of 8%–10% weight. Biocompatible G did not form a conductive pathway in the TPU; resistance to indentation deformation of the TPU matrix was maintained by weight by 40%. Adding a carbon material to the TPU improved the mechanical properties of the composites, and carbon fillers could improve electrical conductivity without losing biocompatibility. For the practical use of the manufactured filaments, optimal printing parameters were determined, and an FDM printing condition was adjusted. Through this process, a variety of soft 3D-printed C/TPU structures exhibiting flexible and robust features were built and tested to investigate the performance of the possible application of 3D-printed electronics and medical scaffolds.

Thermoplastic polyurethane/CNT nanocomposites with low electromagnetic resistance property

“…Good dispersion of carbon nanotubes in TPU matrix may gain better interfacial adhesion, and the nanocomposites would exhibit higher tensile strength and modulus. 86 Incorporating dispersants would achieve better interfacial interaction together with MWCNT, 60,87 and the highest tensile strength is obtained for TPU-MWCNT, which contains 2 wt% MWCNT and 2 wt % dispersants. By adding 2 wt% of MWCNT and dispersant to 1,3-TPU, the tensile strength of the nanocomposite increased from 7.59 MPa to 21.52 MPa, nearly achieving the mechanical property of neat 1,4-TPU.…”

3D printing of highly flexible, cytocompatible nanocomposites for thermal management

“…Thus, PUs can be used in a wide range of molding techniques including compression, blow, injection, and extrusion molding. Furthermore, PUs are appealing candidates in fabrication of bio-structures owing to their biocompatibility features [19][20][21][22][23]. Clearly, nano-fillers can remarkably affect the PUs' morphology by changing the interaction between soft and hard segments.…”

Effects of 3D Printing-Line Directions for Stretchable Sensor Performances

“…When containing conductive components (carbon nanotube, CNT), CNT/TPU is definitely a highlight material to fabricate the stretch sensors [ 17 , 18 , 19 , 20 ]. Following this approach, there are many great studies in the stretch sensing field, which are enhanced with advanced materials based on FDM printing [ 21 , 22 , 23 , 24 , 25 ]. For example, Josef et al [ 26 ] developed 3D printed highly elastic strain sensors of multiwalled carbon nanotube/thermoplastic polyurethane (MWCNT/TPU) nanocomposites.…”