Flexible phase change hydrogels for mid-/low-temperature infrared stealth

Super-flexible phase change materials with a dual-supporting effect for solar thermoelectric conversion in the ocean environment

“…53,54 Similarly, we developed flexible phase change hydrogels based on paraffin wax (PW) microspheres and polyvinyl alcohol (PVA) hydrogels. 55 It is noteworthy that although lots of composite PCMs with enhanced shape stability have been prepared by introducing capillary force, hydrogen bonding, and dipole interaction, only a few reported thus far can maintain shape stability under water without any leakage, which is mainly ascribed to the solubility of the commonly used PCMs in water and the limited confining effect of the supporting materials. 49 Although there have been attempts to employ hydrogel-based supporting networks to accommodate PCMs underwater, PCMs inevitably leak under prolonged water conditions.…”

Construction of Multifunctional Composites for Electromagnetic Shielding and Infrared Stealth Based on Magnetic Phase Change Capsules and Silicone Rubber Foam

“…[ 21a,53 ] On the other hand, thanks to the phase change function, when the temperature is higher than the phase change temperature of NiFe 2 O 4 ‐EPCM (≈53.6 °C), the phase change wax core will melt and store the excess heat as latent heat. [ 20 ] As a consequence, MSRF‐3 prepared in this work can keep low‐heat radiation and achieve IR shielding function in both human body temperature and high‐temperature heat source, so it can be speculated that it will have broad application prospects in military and civil fields.…”

“…[ 15a ] Based on Stefan Boltzmann's law, the IR emission power is the fourth power of the material's absolute temperature, so controlling temperature is key to realize IR stealth. [ 20 ] In terms of this, the temperature modulation technologies offer exciting opportunities to IR stealth, especially the passive regulation based on PCM can achieve IR stealth relying on their thermal shielding and temperature control properties. PCM are commonly used in aerogels, polymers, and other matrices.…”

Preparation and characterization of a form-stable phase change hydrogel for heat-protective clothing

“…These features allow them to undergo reversible volume changes in response to various stimuli, such as water exudation or absorption. 42,43 Besides, phase change hydrogels (PCHs) of different sizes can be simply prepared by encapsulating hydrated salts in a hydrogel system. 44 In this study, a phase change hydrogel was prepared by ionic and covalent cross-linking methods, in which binary eutectic hydrated salts (BEHSs; CaCl 2 Á6H 2 O-MgCl 2 Á6H 2 O) were used as PCMs.…”

“…These features allow them to undergo reversible volume changes in response to various stimuli, such as water exudation or absorption. 42,43 Besides, phase change hydrogels (PCHs) of different sizes can be simply prepared by encapsulating hydrated salts in a hydrogel system. 44…”