Segregated conductive polymer composites (CPCs) have
important
application prospects in the field of electromagnetic interference
(EMI) shielding but suffer from weak mechanical properties that significantly
limit their practical applications. In this work, three-dimensional
(3D) printing is employed to construct continuous thermoplastic polyurethane
(TPU) scaffolds with different interlayer angles of π/5, π/4,
π/3, 2π/5, and π/2. Subsequent carbon nanotube (CNT)
dip-coating and hot-pressing lead to the successful fabrication of
co-continuous segregated CNT/TPU (CNT/TPU-CCS) composites. It is found
that the composites not only achieve high EMI shielding properties
but also obtain excellent mechanical properties. With only 4.0 wt %
of CNT, the CNT/TPU-CCS composites with the interlayer angle of π/3
(CNT/TPU-CCS-π/3) exhibit a high electrical conductivity of
42.2 S/m and a remarkable EMI shielding effectiveness (EMI SE) of
43.1 dB, which are 75% and 72%, respectively, higher than that of
the CNT/TPU composites with conventional segregated structure. The
CNT/TPU-CCS-π/3 composites also have superior mechanical properties,
showing a tensile strength and elongation at break of 17.8 MPa and
377.3%, respectively, which are 196.8% and 1540.6% higher than those
of the conventional segregated CNT/TPU composite. This work provides
a new facile, economic, and efficient strategy to construct segregated
CPCs with both high EMI shielding performance and mechanical properties,
and could promote the practical application of segregated CPCs in
the next-generation electronic devices.