Giant Barocaloric Effects in Natural Rubber: A Relevant Step toward Solid-State Cooling

Solid-state cooling based on i-caloric effects has shown to be a promising alternative to the conventional refrigeration devices. Only very recently, the research on barocaloric materials is receiving a deal of attention due to the demonstration of giant barocaloric effects in shape-memory alloys. Regarding polymers, there is still a lack of literature, despite their high caloric potential. Thus, we present here giant barocaloric effects in natural rubber, a low-cost and environmental friendly elastomer polymer. The maximum values of entropy and temperature changes are larger than those previously reported for any promising barocaloric material. Moreover, the huge normalized temperature change and refrigerant capacity exhibited by natural rubber confirm its high potential for cooling applications. We also verify a relevant dependence of the barocaloric effect on the glass transition in natural rubber. Our findings suggest that commercial refrigeration devices based on barocaloric effects from elastomer polymers can be envisaged in the near future.