Tunable Thermoresponsive Flexible Films for Adaptive Temperature Management and Visual Temperature Monitoring

Abstract

Effective temperature management is essential for human thermal comfort and health. Although various temperature regulation materials have been proposed previously, there are few materials that have the dual functions of temperature monitoring and thermal management. Herein, a thermoresponsive form-stable flexible film based on phase-change materials (PCMs) and polydimethylsiloxane (PDMS) is rationally designed. The resultant versatile PCM@PDMS film is able to absorb and release heat responding to temperature stimuli and good mechanical strength. Moreover, optical visibility of the PCM@PDMS film can be reversibly converted between opaque and transparent states to monitor temperature. The switching principle is that solid PCMs embedded in the PDMS would be melted into liquid PCMs to enable light through the PCM@PDMS. The thermal experiment results suggest that the PCM@PDMS films can effectively regulate the human body temperature to adapt to the demanding environment (self-heating more than 3 °C in the cold environment or self-cooling more than 4 °C in the hot environment). Such dual-function films open a pathway to develop smart personalized thermoregulation materials for human body thermal management and temperature monitoring.

Enhanced Thermal Conductivity of Phase Change Microcapsules Based on Boron Nitride/Graphene Oxide Composite Sheets

“…3 For instance, as intermediate energy storage media, the TES systems can improve the harvesting efficiency of intermittent clean solar and wind energy as well as the utilization of off-peak electricity; as thermal management systems, the TES systems can adjust the temperature of textiles and buildings to a comfortable range, thus reducing energy consumption. So far, TES materials have been widely applied in many advanced military and civil fields, such as personal thermal management, 4,5 newenergy batteries, 6 solar−thermal conversion systems, 7 electronic devices, 3 infrared stealth, 8 wearable applications, 9 and buildings. 10 As one of the most widely used TES materials, latent heat storage materials, namely, phase change materials (PCMs), have attracted intensive interest, thanks to their unique high energy storage and thermostatic capacities.…”

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

“…6 The exibility of PCMs based on polymer systems stems from elastic polymer molecular skeletons [22][23][24][25] or cross-linked polymer networks. [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.…”

“…[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.…”

Impact of varying lactate concentration in sweat on thermo-physiological comfort of multi-layered ensembles

“…were used to fabricate the thermo-regulated fibres (Fang et al, 2021). In addition to it, various temperature regulation materials have been developed nowadays such as thermoresponsive form-stable flexible film based on phase-change materials (PCMs) and polydimethylsiloxane (PDMS) and functionalized textiles capable of biofluid administration which are favourable for enhancing the wet-thermal comfort (Dai et al, 2022;He et al, 2021).…”

“…Maintaining the core temperature is crucial to coordinate bodily functions (Ashrae, 1992; Osilla and Sharma, 2019). Effective temperature management is essential for human thermal comfort and health (Dai et al ., 2022). Parameters like external climatic conditions (such as air temperature, air pressure, humidity and wind speed), extent of activity level (low, vigorous viz walking, running and climbing) and genetic nature of human being (age, gender, fitness, maturity and hormonal behaviour) may lead to changes in the amount of heat absorbed and heat dissipated from the body.…”