Elastocaloric Performance of Natural Rubber in Solid State Cooling: Evaluation of the Effect of Crosslinking Density

Elastocaloric cooling is recognized as a promising alternative to modern vapor-compression cooling systems, which often rely on environmentally hazardous refrigerants. Natural rubber (NR), a well-known renewable resource, stands out among elastomers exhibiting elastocaloric behavior due to a peculia...

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Main Authors: Marica Bianchi, Luca Fambri, Giulia Fredi, Alessandro Pegoretti, Andrea Dorigato
Format: Article
Language:English
Published: MDPI AG 2024-11-01
Series:Applied Sciences
Subjects:
Online Access:https://www.mdpi.com/2076-3417/14/22/10525
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author Marica Bianchi
Luca Fambri
Giulia Fredi
Alessandro Pegoretti
Andrea Dorigato
author_facet Marica Bianchi
Luca Fambri
Giulia Fredi
Alessandro Pegoretti
Andrea Dorigato
author_sort Marica Bianchi
collection DOAJ
description Elastocaloric cooling is recognized as a promising alternative to modern vapor-compression cooling systems, which often rely on environmentally hazardous refrigerants. Natural rubber (NR), a well-known renewable resource, stands out among elastomers exhibiting elastocaloric behavior due to a peculiar combination of nontoxicity, low cost, softness, long-life fatigue and high caloric power. Despite these properties, research on the refrigeration potential of NR is still in its early stages, and several aspects require attention. This work investigates, for the first time, the effect of crosslinking density on the elastocaloric properties of NR. Samples with three different crosslinking densities (2.9, 4.0 and 5.2 mol·10<sup>−4</sup>/cm<sup>3</sup>) were produced by internal compounding and hot pressing, and thermo-mechanically characterized. The assessment of the elastocaloric effect of the produced samples revealed that reducing the crosslinking degree significantly enhanced the elastocaloric properties. To compare the cooling capacity of the samples, a qualitative coefficient of performance (COP<sub>mat</sub>) was evaluated as the ratio between extracted thermal energy and deformational work per unit volume. The results highlight that the least crosslinked sample achieved the higher COP<sub>mat</sub>, equal to 2.4. These results underscore the significance of crosslinking density as one of the primary factors to be considered to enhance the refrigeration potential of NR.
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spelling doaj-art-e48c9bbfa55746eaa92f705b6aab71012025-08-20T01:53:49ZengMDPI AGApplied Sciences2076-34172024-11-0114221052510.3390/app142210525Elastocaloric Performance of Natural Rubber in Solid State Cooling: Evaluation of the Effect of Crosslinking DensityMarica Bianchi0Luca Fambri1Giulia Fredi2Alessandro Pegoretti3Andrea Dorigato4INSTM Research Unit, Department of Industrial Engineering, University of Trento, Via Sommarive 9, 38123 Trento, ItalyINSTM Research Unit, Department of Industrial Engineering, University of Trento, Via Sommarive 9, 38123 Trento, ItalyINSTM Research Unit, Department of Industrial Engineering, University of Trento, Via Sommarive 9, 38123 Trento, ItalyINSTM Research Unit, Department of Industrial Engineering, University of Trento, Via Sommarive 9, 38123 Trento, ItalyINSTM Research Unit, Department of Industrial Engineering, University of Trento, Via Sommarive 9, 38123 Trento, ItalyElastocaloric cooling is recognized as a promising alternative to modern vapor-compression cooling systems, which often rely on environmentally hazardous refrigerants. Natural rubber (NR), a well-known renewable resource, stands out among elastomers exhibiting elastocaloric behavior due to a peculiar combination of nontoxicity, low cost, softness, long-life fatigue and high caloric power. Despite these properties, research on the refrigeration potential of NR is still in its early stages, and several aspects require attention. This work investigates, for the first time, the effect of crosslinking density on the elastocaloric properties of NR. Samples with three different crosslinking densities (2.9, 4.0 and 5.2 mol·10<sup>−4</sup>/cm<sup>3</sup>) were produced by internal compounding and hot pressing, and thermo-mechanically characterized. The assessment of the elastocaloric effect of the produced samples revealed that reducing the crosslinking degree significantly enhanced the elastocaloric properties. To compare the cooling capacity of the samples, a qualitative coefficient of performance (COP<sub>mat</sub>) was evaluated as the ratio between extracted thermal energy and deformational work per unit volume. The results highlight that the least crosslinked sample achieved the higher COP<sub>mat</sub>, equal to 2.4. These results underscore the significance of crosslinking density as one of the primary factors to be considered to enhance the refrigeration potential of NR.https://www.mdpi.com/2076-3417/14/22/10525natural rubbervulcanizationcrosslinking densityelastocaloric effectsolid state cooling
spellingShingle Marica Bianchi
Luca Fambri
Giulia Fredi
Alessandro Pegoretti
Andrea Dorigato
Elastocaloric Performance of Natural Rubber in Solid State Cooling: Evaluation of the Effect of Crosslinking Density
Applied Sciences
natural rubber
vulcanization
crosslinking density
elastocaloric effect
solid state cooling
title Elastocaloric Performance of Natural Rubber in Solid State Cooling: Evaluation of the Effect of Crosslinking Density
title_full Elastocaloric Performance of Natural Rubber in Solid State Cooling: Evaluation of the Effect of Crosslinking Density
title_fullStr Elastocaloric Performance of Natural Rubber in Solid State Cooling: Evaluation of the Effect of Crosslinking Density
title_full_unstemmed Elastocaloric Performance of Natural Rubber in Solid State Cooling: Evaluation of the Effect of Crosslinking Density
title_short Elastocaloric Performance of Natural Rubber in Solid State Cooling: Evaluation of the Effect of Crosslinking Density
title_sort elastocaloric performance of natural rubber in solid state cooling evaluation of the effect of crosslinking density
topic natural rubber
vulcanization
crosslinking density
elastocaloric effect
solid state cooling
url https://www.mdpi.com/2076-3417/14/22/10525
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AT lucafambri elastocaloricperformanceofnaturalrubberinsolidstatecoolingevaluationoftheeffectofcrosslinkingdensity
AT giuliafredi elastocaloricperformanceofnaturalrubberinsolidstatecoolingevaluationoftheeffectofcrosslinkingdensity
AT alessandropegoretti elastocaloricperformanceofnaturalrubberinsolidstatecoolingevaluationoftheeffectofcrosslinkingdensity
AT andreadorigato elastocaloricperformanceofnaturalrubberinsolidstatecoolingevaluationoftheeffectofcrosslinkingdensity