Biobased Elastomer Films with High Photothermal Capability for Ice Melting and Remotely Controlled Reconfiguration Enabled by Eumelanin from Cuttlefish Juice

The depletion of fossil resources has heightened the importance of utilizing clean energy, making high-performance photothermal conversion materials essential for sustainable energy capture. While most current photothermal research focuses on thin films and hydrogels, rubber materials represent a promising alternative due to their flexibility, light weight, ease of processing, and corrosion resistance. In this study, we developed a biobased rubber material cross-linked through dynamic β-hydroxy ester bonds that exhibits tunable mechanical properties and efficient photothermal conversion. The material was prepared by incorporating eumelanin obtained from cuttlefish ink sacs into a blend of epoxidized and neat Eucommia ulmoides gum (EUG). The mechanical properties could be precisely tailored by varying the crystalline EUG content, yielding a tensile strength ranging from 2.01 to 19.62 MPa and an elongation at break between 45 and 720%. Rich in π–π conjugated structures, eumelanin serves as an efficient biobased photothermal agent. Loading only 1 phr eumelanin, the composite rapidly reached 110 °C within 100 s under 0.5 W/cm2 near-infrared irradiation, with the temperature rise finely adjustable via eumelanin loading or light intensity. Leveraging these properties, we demonstrated the material’s potential for applications in ice melting as well as remotely controlled shape memory and reconfigurable devices. This work provides an alternative strategy for functionalizing biobased rubber materials and highlights promising pathways toward sustainable, high-value applications.