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Yan et al. Soft Sci. 2025, 5, 8 https://dx.doi.org/10.20517/ss.2024.66 Page 11 of 34

resulting in excellent mechanical durability of the composites, which maintained stable electrical
conductivity and EMI shielding capability after 1,000 bending tests. These outcomes are ascribed to the
hierarchical structure of the nanoscale SWCNTs/rGO network and the macroscale PF skeleton, which
produce superior EMI shielding performance, which provides a valuable guideline for next-generation
wearable electronic devices in terms of improving EMI SE. In summary, the properties of various Flexible
EMI Composites are detailed in Table 2.

Flexible phase change composites
PCMs exhibit excellent thermal storage during phase transitions caused by variations in external
temperature, which have garnered significant attention in the areas of thermal management and thermal
[110]
energy storage . However, most PCMs suffer from issues such as leakage and low thermal conductivity,
which limit their practical applications [111,112] . To address these issues, three encapsulation techniques can be
[117]
employed to effectively prevent leakage of PCMs: microencapsulation [113-116] , porous adsorption , and
polymer molding [118-120] . Additionally, if PCMs become more flexible to tolerate a certain amount of
deformation and to make closer contact with the substrate surface, this will apply to a wider range of
application scenarios, ultimately providing better thermal management capabilities.

Based on microencapsulation
Microencapsulation is an effective method for preventing PCM leakage by encapsulating pulverized solid or
liquid particles in a solid shell, thereby isolating the PCM from the external environment. It also expands
the region for heat transfer, prevents the PCM from leaking during repeated thermal cycling, and enables
the support material to withstand the frequent volume changes of the core PCM during phase
[121]
transitions . The resulting microencapsulated PCM (micro-PCM) can achieve shape-stable structures,
overcoming the limitations of bulk PCMs and making them suitable for various practical applications. Shen
et al. prepared phase change microcapsules [microcapsule PCM (MPCM)] with high energy storage density
using n-octadecane, melamine formaldehyde resin, and TiO nucleating agent, which were then
2
supplemented with polyurethane acrylate (PUA) and MXene to construct phase change composites (PCCs)
[122]
with shape-stabilized excellent thermal storage and thermal management as a whole [Figure 4A] . The
results indicated that the composite had a subcooling of 0 °C and an enthalpy of phase change of 183.7 J/g,
demonstrating excellent thermal storage capability. Additionally, the thermal conductivity is increased by
48.1% compared with that of MXene-free, which is conducive to heat transfer and heat dissipation in
practical applications. Furthermore, the flexibility imparted by PUA further expands the application scope
of the composites, with significant potential in the thermal management of electronic materials. Not only
that, the PCM encapsulation technology brought by microcapsule technology can also be used for thermal
management of the human body using spinning. Ma et al. prepared a kind of fiber membrane based on
MPCM and uniaxial electrostatic spinning [Figure 4B] . To stop leaks during the phase change process, n-
[123]
octadecane was successfully encapsulated utilizing microencapsulation technology. The MPCM [silver
nanoparticle-modified MCPM (APCM)] was then modified in situ using Ag nanoparticles to improve its
electrical and thermal conductivity. The PCC fiber membrane was prepared via continuous uniaxial
electrostatic spinning with the phase change medium as the matrix of APCM and PVDF as the matrix resin
to effectively prevent its displacement or separation during use. Subsequently, the composite phase change
film was obtained by modification with polydopamine (PDA) and PPy. The composite film not only has an
ideal enthalpy (90.34 J/g) but also demonstrates outstanding photothermal and electro-thermal conversion
capabilities as a result of PDA and PPy working in concert, allowing the body to accomplish all-season
thermal comfort control in any weather conditions and at any time of day. Moreover, the composite film
has excellent flexibility and mechanical strength and can be folded into a “crane” without any cracks or
breaks, ensuring the comfort and long-term durability and stability of the composite phase change film as a
wearable product, making it an excellent candidate for personal thermal management.