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Page 20 of 34 Yan et al. Soft Sci. 2025, 5, 8 https://dx.doi.org/10.20517/ss.2024.66

greatly broadening its potential applications. The methodology presented in this work provides a promising
new approach for the development and preparation of integrated multifunctional PMP films that can be
used in the field of flexible wearable electronics with effective thermal management and EMI shielding.

Carbon nanomaterials, such as CNTs, graphene, etc., can also be combined with polymer matrix and PCMs
to achieve dual-functionality in both EMI shielding and thermal management. Yang et al. fabricated flexible,
thin, and robust phase-change nonwoven fabric (PCNF) in a scalable manner using SWCNTs-embedded
PEG-grafted TPU (TPEG) prepolymers as phase change filaments (PCWs) by a simple, accurate, and
[142]
controllable 3D printing strategy [Figure 8A] . Because of their exceptional mechanical resilience and
remarkable flexibility, PCNF films can tolerate a wide range of extreme deformations, including folding,
coiling, and bending. They can even be readily kneaded into flat surfaces without suffering any structural
fracture. This makes them ideal for use as wearable fabrics. Additionally, SWCNTs uniformly embedded
within the PCNF network absorb and reflect EMWs multiple times, resulting in excellent electromagnetic
shielding performance. Moreover, the film exhibits excellent thermal properties, and the test of placing it
into the jacket liner reveals that the temperature at this location is significantly lower compared with other
parts, showing the superior thermal regulation performance of the PCNF. Also using SWCNTs as a
conductive filler to prepare flexible EMI PCMs is Ge et al, who proposed a phase change composite
[143]
SWCNT/PEG/PDMS (SPP) consisting of two fillers, SWCNTs and PEG, in a PDMS matrix [Figure 8B] .
Among the two fillers, SWCNTs contribute to the dielectric properties necessary for microwave attenuation.
Compared to MWCNTs, SWCNTs have a smaller diameter and larger aspect ratio, resulting in a lower
percolation threshold. This minimizes the filler loading, thereby leaving more space for the PCM to enhance
energy storage density. The results show that the crosslinked network structure of the PDMS matrix plays a
role in the excellent mechanical properties of the composites, making it easy to bend and twist to maintain
its flexibility. Additionally, the fast chain dynamics and crosslinking properties enable the PDMS molecules
to move and recover rapidly. Furthermore, the EMI shielding capability of the SPP is synergistically
enhanced by conduction losses in the SWCNT network, interfacial polarization between the SWCNTs and
the polymer matrix, and dipolar polarization of the polymer. Since SPP has good phase transition properties
and high latent heat, it can be used as a heat sink or buffer layer to stabilize the temperature fluctuation of
electronic devices, so the material may become a multifunctional material for EMI shielding and thermal
management, especially in the miniaturization of electronic devices. In addition, Li et al. prepared
PP/CNTs/Fe O /PW shape-stabilized PCCs (SSPCCs) by scalable melt mixing, salt templating, and vacuum
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impregnation methods [Figure 8C] . The integration of CNTs, which form an enhanced thermal
[144]
conduction path, with the regular porous structure of the SSPCCs led to remarkable thermal conductivity
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(0.59 W·m ·K ), good thermal stability, and high enthalpy (133.8 J/g), enabling a reduction of the
smartphone’s operating temperature by 10 °C due to its superior temperature control effect. Furthermore,
due to the increase in the Fe O content, the EMI shielding effect of the SSPCCs was gradually increased
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with the SE as high as 41.20 dB, which was attributed to the high electrical conductivity and Fe O
T
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magnetism of SSPCCs. Meanwhile, the significant mechanical strength and flexibility offer the possibility of
multifunctional applications for flexible electronic devices.
Because of its high electrical conductivity and huge surface area, graphene filler has been shown to improve
the thermal conductivity of composites while also being a perfect material for creating high-performance
EMI shielding materials. Its excellent properties have led many researchers to utilize it in constructing a
diverse range of composites with varied functionalities [96,97] . Liang et al. added polystyrene microspheres as
[145]
hard stencils into GO, and then impregnated PW to obtain multifunctional integrated films [Figure 9A] .
The addition of PS microspheres caused a large number of bubble-like micropores to develop inside the
graphene-based structure. These bubble-like micropores increase the capillary force between PW and the