Melamine Foam-Supported Form-Stable Phase Change Materials with Simultaneous Thermal Energy Storage and Shape Memory Properties for Thermal Management of Electronic Devices

Abstract

Paraffin wax (PW) is widely used as a phase change material (PCM) in the thermal energy storage field, whereas the leakage and strong rigidity of PW have hindered its practical applications. In this work, binary melamine foam (MF)/PW blends with simultaneous thermal energy storage and shape memory properties were prepared through vacuum impregnation. Herein, PW performs as a latent heat storage material and as a switching phase for shape fixation and MF serves as a supporting material to prevent the leakage and as a permanent phase for shape recovery. Due to the light weight and super-elasticity of MF, the MF/PW PCMs possess not only good encapsulation ability and a high latent heat, but also excellent shape-fixing and recovery properties (shapefixing and recovery ratios are about 100%). Besides, the MF/PW PCMs can be fabricated into arbitrary shapes using MF as a template, and they exhibit excellent shape memory cyclic performance and thermal reliability. A temperature-sensitive and temperature-controlled deployable panel is further established, which can be installed in the electronic device and used for temperature protection. With high thermal energy storage capability, excellent shape memory properties, shape designability, and stable cycling reliability, this multifunctional MF/PW PCM shows a promising application in thermal energy management systems.

Compressible Metalized Soft Magnetic Sponges with Tailorable Electrical and Magnetic Properties

“…Due to low mass density, the specific volume saturation magnetization of Co coated sponge should have an even lower value in contrast to that of bulk materials. However, we can see that the specific mass saturation magnetization of cobalt coated sponge has been close to bulk nickel and much better than many other compressible magnetic sponges, thus showing enormous application potential in many fields, such as magnetic separation, magnetic sensors and actuators, electromagnetic energy conversion, etc. The manipulation of these magnetic sponges under external magnetic field was shown in Figure S11 and Movie S1, S2.…”

“…demonstrated the carbonized melamine foams could present extraordinary compressibility when heat treated at less than 800 °C . Besides, in‐situ coating techniques of various substances on melamine sponge skeleton has also been studied to impose new functionalities onto the sponges, such as fire retardancy, conductivity, magnetism, hydrophobicity, antibacterial, thermal management . However, most of the proposed coating or deposition methods either result in poor coating quality or require complicated multi‐step operation, and thus largely limit the practical applications of melamine sponges in these fields.…”

“…[36] Besides, insitu coating techniques of various substances on melamine sponge skeleton has also been studied to impose new functionalities onto the sponges, such as fire retardancy, [37] conductivity, [38,39] magnetism, [40] hydrophobicity, [41,42] antibacterial, [43] thermal management. [44] However, most of the proposed coating or deposition methods either result in poor coating quality or require complicated multi-step operation, and thus largely limit the practical applications of melamine sponges in these fields. In this manuscript, a one-step surface modification strategy was adopted based on dopamine-induced free radical polymerization reaction to covalently graft polymer brushes that contain quaternary ammonium cations onto the surface of sponge fiber, and then the modified surface was activated through electrostatically attracting negative catalyst moieties, such as PbCl 4 2À , for inducing the subsequent in-situ electroless deposition of metals, and finally metal coating layer with a uniform thickness can be obtained on the fiber surface.…”

Form‐stable phase‐change materials supported by 1‐octadecylamine‐modified montmorillonite for latent heat storage

“…1,2 Organic phase-change materials (PCMs) used as LHS devices are an exceptionally promising approach to alleviate these aforementioned concerns by providing reversibly high thermal energy storage (TES) capacities with isothermal operating characteristics during the phase transition process. [3][4][5][6] Recently, organic PCMs, such as paraffin wax, [7][8][9] fatty alcohols, [10][11][12][13] fatty acids, [14][15][16] fatty amines, [17][18][19] and polyethylene glycol, 20,21 have been extensively employed as TES and thermal management systems (TMS) for energy-saving buildings, [22][23][24][25][26] electronic devices, 27,28 lithium-ion batteries, [29][30][31][32] solar energy harvesting plants, 33,34 waste heat recovery, 35 and smart thermos-regulated textiles 36 according to their various merits, such as high Dongli Fan and Yuan Meng contributed equally to this work.…”

Microencapsulation of stearic acid with SiO2 shell as phase change material for potential energy storage

“…interfacial polymerization [25][26][27][28] , in situ polymerization [29][30][31][32] , coacervation [33][34][35] , and sol-gel process [36][37][38][39] . Formaldehyde resin can be used for microencapsulation [40][41][42][43] . Use of melamine-formaldehyde and urea-formaldehyde resins as shell materials usually release poisonous formaldehyde during application.…”