| It is still a big challenge to obtain shape-stabilized nanoencapsulated core-shell phase change materials(NC-PCM)with the encapsulation ratio up to 90wt%via surfactant-free method due to the lack of novel nanoencapsulation method and related mechanism.Herein,we for the first time report a novel supramolecular lock shell layer technique without surfactant to facilely prepare shape-stabilized NC-PCM with the encapsulation ratio range of 70-90 wt%.To this aim,amphiphilic macromolecular nanoreactors with the particle size of?15 nm were firstly synthesized.n-dodecanol as the heat storage core was then self-assembled into the nanoreactors under ultrasonification.A thin layer of crosslinked acrylates copolymers was prepared by in-situ grafting polymerization to further stabilize the potentially leaked n-dodecanol.Crystalline structure,morphology,and thermal behavior of the resulting NC-PCM were extensively investigated.Relevant results indicate that the obtained NC-PCM fluids show excellent storage stability in the temperature range of-50-50?,benefiting from their small particle size(40-90 nm)and intense supramolecular interactions between n-dodecanol and the prepared nanoreactors.Phase change temperature of the produced NC-PCM is very close to that of neat n-dodecanol,no obvious supercooling phenomena have been detected for the produced NC-PCM.DSC and TGA tests indicate the the content of nanoreactor inferenced the encapsulation efficiency and thermal stability.NC-PCMs containing 20 wt%of nanoreactor show the best in overall terms(EEDSC>98%).The maximum encapsulation ratio,latent heat,and thermal conductivity of the shape-stabilized NC-PCM approximate 90wt%,180 J g-1,and 0.1705 W m-1K-1,respectively,implying large potential application in the sectors of solar energy storage,waste heat management etc.The developed supramolecular lock-layer technique probably opens a new avenue in the search for NC-PCM with ultrahigh mass content of core layer. |
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