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Page 2 of 34 Yan et al. Soft Sci. 2025, 5, 8 https://dx.doi.org/10.20517/ss.2024.66

potential research directions for flexible EMI shielding PCCs, hoping to contribute to the rapid advancement of
next-generation flexible electronics, human thermal management, and artificial intelligence.

Keywords: Electromagnetic interference shielding, phase change composites, polymer matrix, flexible

INTRODUCTION
As electronic devices and communication technology advance rapidly, the transmission density of
electromagnetic waves (EMWs) has increased, and electromagnetic radiation has gradually become an
urgent issue in using new energy . On the one hand, unnecessary EMWs can interfere with the normal
[1-7]
operation of electronic devices, thereby reducing their lifespan. On the other hand, excessive exposure of
the human body to EMWs can lead to various health issues, such as a higher risk of nausea, dizziness,
palpitations, insomnia, and even reduced immunity [8-10] . Therefore, electromagnetic interference (EMI)
shielding has become a significant focus of research, and the design of materials with efficient EMI shielding
has great prospects for development [11-14] .

Traditional EMI shielding materials such as metals (Cu, Al, Ni, etc.) are widely used because of their
outstanding electrical conductivity and fast electron transfer rate. However, their high density, susceptibility
to corrosion, processing challenges, and limited flexibility constrain their application in small and medium-
sized electronic devices. Therefore, designing lightweight, flexible EMI shielding materials is urgent and
essential [15-17] . Polymers offer unique advantages, including low density, corrosion resistance, high
mechanical strength, and adjustable elasticity [18,19] . They are considered potential candidates for flexible EMI
shielding material substrates and are favored by numerous researchers [20-22] . Intrinsically conductive
polymers such as polyacetylene, polypyrrole (PPy), polyaniline, and polythiophene can significantly
improve conductivity through doping, thereby exhibiting excellent EMI shielding behavior and effectively
mitigating secondary EMI pollution by absorbing losses [23,24] . However, their molecular chains are generally
rigid, which complicates processing. In contrast, the addition of conductive fillers to traditional polymers
not only enables flexible design and easier processing but also enhances conductivity, thereby improving
EMI shielding performance [25-30] . Various fillers with excellent conductivity, including MXene [31-33] (transition
metal carbides and nitrides), carbon-based materials [34-38] [graphene, carbon nanotubes (CNTs), carbon
black], and metal nanoparticles [39-43] [silver nanowires (AgNWs), Ag, liquid metals], have been used in
conjunction with polymer matrices to prepare lightweight and effective EMI shielding materials.

EMW overload is often accompanied by heat accumulation, which can lead to overheating electronic
devices, thereby reducing their precision and potentially damaging them. As a result, a single EMI shielding
material cannot fully meet the demands of modern electronic devices. The development of flexible materials
that provide both electromagnetic shielding and thermal management performance (TMF-EMI) has thus
become a major research focus [44-48] . Phase change materials (PCMs) exhibit excellent properties, such as
excellent thermal storage, stable thermochemical characteristics, and adjustable phase change temperatures,
making them promising for thermal management and waste heat recovery in electronic devices [49-51] .
However, issues such as leakage and poor thermal conductivity of PCMs pose significant challenges to their
practical application. These problems can be addressed by encapsulating the materials and incorporating
thermally conductive fillers [52-55] . Consequently, combining PCMs with lightweight EMI materials to
construct flexible EMI shielding thermal management composites is no longer difficult.

In response to this, the article offers a systematic summary of recent advances in flexible EMI shielding
materials and the potential applications of PCMs for thermal management and provides a comprehensive
introduction to lightweight EMI shielding composites with thermal management capabilities (The structure