Synchronous Visual/Infrared Stealth Using an Intrinsically Flexible Self‐Healing Phase Change Film

Abstract

Phase change materials (PCMs) have been particularly concerned as infrared stealth functional materials due to their superior thermal management capability. However, traditional PCMs usually behave rigid solid or flowing liquid states with fixed transition temperature, greatly limiting their application especially in multi-band stealth and multiple scenes. Herein, an intrinsically flexible self-healing phase change film used for synchronous visual/infrared stealth for the first time is designed and constructed. The phase change film possesses a solid-solid phase transition behavior with adjustable transition temperature (from 38.8 to 51.1 °C) and enthalpy (from 79.7 to 116.7 J g −1 ), long-term cycling stability (500 cycles), and outstanding flexible and selfhealing performance. Remarkably, the phase change film can be customized with different colors and various configurations to exhibit attractive visual stealth functions in multiple scenes. Additionally, owing to phase transition property, this phase change film can possess a thermal management capability and behave infrared stealth performance for objectives at various temperatures. Combining the above unique functions, the intrinsically flexible self-healing phase change film developed in this work may show great potential for applications in the synchronous visual/infrared stealth across a wide range of scenarios and temperatures.

Ultraflexible, cost-effective and scalable polymer-based phase change composites for wearable thermal management

“…Fig. 4f presents a comprehensive comparison of the maximum latent heat and degree of flexibility achievable by various typical shaped matrixes [24][25][26][38][39][40][41][42][43][44][45][46][47][48][49][50] . Encouragingly, higher enthalpies and stretchability of F-FSPCMs are achieved in this work.…”

Highly Stretchable Ti3C2Tx MXene-Integrated Phase Change Films for Solar-Thermal Harvesting and Infrared Stealth

“…Although the body can spontaneously modulate its temperature, extremely hot or cold working conditions can disrupt the thermal balance and even pose a threat to human health. Currently, individual thermal management has been seen as an effective alternative to centralized space cooling/heating methods with high energy consumption due to its convenience and sustainability. , At the same time, personal thermal management technology is expected to achieve infrared stealth by controlling the surface temperature of the human body to suppress infrared scattering, which is essential to the advancement of the defense industry and novel military devices. − Composite materials based on phase change materials (PCMs) have been proving to have great potential in the field of thermal management due to their thermal energy storage capacity and the reversibility of thermal cycles. − However, these previously developed PCM composites have significant practical limitations in terms of fluid leakage and strong mechanical rigidity, making them unavailable for wearable thermal management. − …”

Flexible composite phase change materials with enhanced thermal conductivity and mechanical performance for thermal management

“…[26][27][28][29] However, the low intrinsic thermal conductivity of organic solid-liquid PCMs and polymers makes exible composite PCMs containing polymer supporting structures suffer from a slow thermal response. [27][28][29][30] Therefore, it is necessary to introduce thermally conductive llers to promote heat transfer in polymer-based exible composite PCMs when used in advanced thermal management systems. 31,32 Commonly used thermally conductive llers, including carbon nanotubes (CNTs), 33,34 graphene nanoplatelets (GNPs), 26 and boron nitride (BN), 35 have been used to improve the thermal conductivity of exible PCMs.…”

“…26–29 However, the low intrinsic thermal conductivity of organic solid–liquid PCMs and polymers makes flexible composite PCMs containing polymer supporting structures suffer from a slow thermal response. 27–30 Therefore, it is necessary to introduce thermally conductive fillers to promote heat transfer in polymer-based flexible composite PCMs when used in advanced thermal management systems. 31,32…”