Preparation and characterization of polyethylene glycol/polyurea composites for shape stabilized phase change materials

Abstract

A linear polyurea (LPU) and a crosslinked polyurea (CPU) were respectively synthesized by condensation between 4,4 0 -diaminodiphenyl methane and multivariate isocyanates, and then were used as supporting material to load polyethylene glycol (PEG) for shape-stabilized phase change materials (ssPCMs). LPU has an incompact flocculent morphology with higher surface area and pore volume than CPU, and CPU is composed of contiguous bead particles with many interspaces. The shape stability of PEG/CPU ssPCMs is better than that of PEG/LPU ssPCMs with the same PEG mass fraction due to the different molecular interactions between PEG and the polymer matrix. The maximum PEG mass fraction in PEG/LPU and PEG/CPU ssPCMs LPU are 65% and 75%, respectively, and the corresponding melting phase change enthalpies are 82.66 J/g and 98.13 J/g, respectively. The heat storage efficiency of PEG/CPU ssPCMs is smaller than that of PEG/LPU ssPCMs with the same PEG content, caused by the greater movement restriction of PEG chains from the crosslinked network of CPU. The prepared ssPCMs have favorable reusability after 100 heating-cooling thermal cycles and have good thermal stability below 250 C, which is helpful to widen extent of application for latent heat storage.

Form‐stable phase change materials supported by nanostructured zinc polyacrylate weakening super cooling of polyethylene glycol

“…15,16 As one of the most important organic PCMs, polyethylene glycol (PEG) has been studied and utilized for thermal energy storage 17 and life science applications, 18 in virtue of its unique advantages including non-toxicity, biocompatibility, suitable phase change temperature and chemical reactivity with specific reagents. [19][20][21][22] However, as a solid-liquid PCM, PEG suffers from leakage in melting process, which restricts its applications in the field of thermal energy storage. 23,24 For this reason, PEG is always conserved with so-called supporting materials to acquire form-stable PCMs (FSPCMs), which avoid the leakage issue in phase transition processes.…”

“…The organic PCMs mainly include alkanes, fatty acids and fatty alcohols 15,16 . As one of the most important organic PCMs, polyethylene glycol (PEG) has been studied and utilized for thermal energy storage 17 and life science applications, 18 in virtue of its unique advantages including non‐toxicity, biocompatibility, suitable phase change temperature and chemical reactivity with specific reagents 19–22 . However, as a solid–liquid PCM, PEG suffers from leakage in melting process, which restricts its applications in the field of thermal energy storage 23,24 .…”

A solid–solid phase change material with wide service temperature range based on polyethylene glycols with different molecular weights

“…PEG is one of the most important organic PCMs for thermal energy storage and thermal management, which has some distinct merits compared with other PCMs, such as nontoxicity, high biocompatibility, good thermal stability, and ease of chemical reaction. [16][17][18][19] PEG suffers from leakage in the melting process, which limits its application for thermal energy storage and thermal management. 20,21 In order to solve this issue, PEG is always reacted with specific chemicals to form chemical or physical crosslinking structure resulting in solid-solid PCMs (SSPCMs), 22,23 or combined with supporting materials to achieve form-stable PCMs (FSPCMs).…”

“…Organic PCMs include fatty alcohols and fatty acids, alkanes, and polyethylene glycol (PEG). PEG is one of the most important organic PCMs for thermal energy storage and thermal management, which has some distinct merits compared with other PCMs, such as non‐toxicity, high biocompatibility, good thermal stability, and ease of chemical reaction 16–19 . PEG suffers from leakage in the melting process, which limits its application for thermal energy storage and thermal management 20,21 .…”

Preparation of a thermally conductive phase‐change coating with good anti‐corrosion

“…Phase change materials (PCMs) are innovative materials that efficiently absorb and release a significant amount of energy during phase transformation, serving for temperature regulation and energy storage 29–31 . Polyethylene glycol (PEG) is a well‐known kind of PCMs, which emerges as a highly promising solid–liquid PCM due to its exceptional qualities, such as low vapor pressure, excellent chemical and thermal stability, appropriate phase transition temperature, lack of supercooling, and nontoxic nature 32–34 . PEG also exhibits some drawbacks which would limits its practical applications.…”