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Page 24 of 34 Yan et al. Soft Sci. 2025, 5, 8 https://dx.doi.org/10.20517/ss.2024.66

thermal conductivity to the composites, combined with the excellent thermal storage of the PCM,
accompanied by the excellent EMI shielding performance and excellent thermal management capabilities,
which have been widely used by researchers in recent years for the preparation of ultra-flexible EMI PCCs.
Guo et al. plated silver in situ on hard ferromagnetic NdFeB to improve its thermal and electrical
conductivity, then used styrene-ethylene/propylene-styrene block copolymer (SEPS) to make a flexible
skeleton and mixed with paraffin wax (PA) to obtain PA/SEPS (PSP), and finally, the NdFeB@Ag magnets
were immediately mixed with the PSP melt, and then underwent a magnetic induction process to construct
a directional interconnection network, resulting in the fabrication of an adjustable flexible and magnetically
fastened PCM (FMP) [Figure 10A] . The material benefits from the typical block structure and inherent
[147]
flexibility of SEPS, along with the ability of NdFeB@Ag to dissipate stresses and reduce stress
concentrations, which increases the tensile strength and ensures the flexibility of the FMP. Consequently,
the FMP can withstand significant mechanical impacts, such as bending, torsion, and rolling, without
cracking. FMP also exhibits excellent EMI shielding performance, which can be attributed to the fact that
most of the impedance mismatch occurs when EMWs irradiate the EMP surface and are directly reflected,
and the interaction of the incoming EMWs with the high-density charge carriers accelerates the interfacial
polarization and conduction loss of EMW. In addition, the orientation and porous network offer numerous
stacking interfaces for repeated reflections and absorptions, and this structure significantly lengthens the
propagation path of the EMWs, which is advantageous for significant energy attenuation of the surviving
-1
-1
EMWs through hysteresis loss. Meanwhile, FMP has high thermal conductivity (2.59 W·m ·K ) and energy
storage density of up to 120 J/g. FMP can be used for Joule-heat-driven active thermal management and
solar-driven energy storage conversion, and this work provides a new strategy for the design of metal
particles for EMI and heat transfer, which makes the composite materials useful for high-power
semiconductor devices and energy utilization systems with promising applications. Inspired by mussels,
Xiao et al. used melamine foam (MF) with a 3D porous structure as a template, constructed a conductive
network by chemical silver plating, introduced strong adhesive PDA, and subsequently vacuum
[148]
impregnated PEG to obtain flexible composites (MPA -PEG) [Figure 10B] . Based on the excellent
χ
deformation and recovery ability brought by MF, the composites still have good deformation ability even
after being encapsulated by AgNPs, and can be easily bent, twisted, and stretched. The successful
construction of the continuous 3D conductive Ag network gives the MPA -PEG PCM the required
χ
electrical conductivity. A portion of the EMW is instantly reflected when it hits the material’s surface
because of the impedance mismatch caused by the high electrical conductivity, and the remaining wave
enters the interior to be rapidly captured and dissipated by the high electron density AgNPs through ohmic
losses, while the internal multiple reflections eventually dissipate it. Overall, the excellent EMI shielding
performance (SE up to 82.02 dB) exhibited by the composites is a result of the combination of high
T
conductivity and the porous structure that brings about reflection, absorption, and multiple reflection
shielding mechanisms. In addition, MPA -PEG also has a high energy storage density (148.9 J/g) and
χ
thermal conductivity, which is used for smartphone thermal management. The composite material’s
flexibility makes it simple to cover the smartphone CPU’s surface, which helps accelerate the heat transfer
by lowering the thermal resistance, and the operating temperature is significantly slowed down when the
CPU is wrapped by MPA -PEG, and when the CPU is wrapped with MPA -PEG, the operating temperature
χ
χ
slows down significantly, and its maximum temperature is much lower than that of the pure CPU, which
means that the PCM in the composite material can absorb a large amount of heat generated by the CPU and
has excellent thermal management capability. A typical example of also using AgNWs as a conductive filler
to provide EWI functionally integrated PCMs is presented by Liang et al., who proposed wrapping
polyethylene terephthalate (PET) textiles with AgNWs and then encapsulating them in PEG with 3-
isocyanatopropyltriethoxysilane (IPTS) crosslinked phase change coating to obtain a composite textile
material with flexible thermally responsive EMI shielding performance and excellent heat dissipation
function [Figure 10C] . The homogeneous distribution of AgNWs along the textile’s in-plane direction
[149]