To overcome the disadvantages of difficulty in reprocessing due to rigidity of the thermosetting polymer, a dynamic polymer chain in which a cross-linking reaction is formed by using reversible covalent bonds is being created. However, because most research is focused on synthesizing different dynamic polymers, research on deriving performance through the formation of a composite material with other materials is insufficient. This study proposes a method for fabricating composite materials of carbon nanofibers and polydisulfide networks (PDSN) and analyzes their changes in thermal, physical, and self-healing properties. The composite materials exhibit high thermal conductivity (0.451 W mK −1 ) and excellent tensile performance (Young's modulus: 0.819 MPa) due to the introduction of carbon nanofibers into a polymer structure. In addition, the composite material maintains adhesive force derived from reversible S−S covalent bonding of the PDSN as well as self-healing and shape memory performance.

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Recently, the quality of life of human has been increasingly threatened by noise caused by various surroundings. To prevent damage from noise, research is being conducted on materials that are capable of both blocking noise in a wide frequency range and transferring frictional heat generated from the noise blocking. In this study, using porous melamine foam (MF) as the basic material, a three-dimensional (3D) lamellar structure with excellent sound absorption and thermal conductivity was manufactured using the dipping process and vapor deposition polymerization, respectively. The 3D lamella structure shows excellent sound absorption performance in a wide frequency range of 250–6300 Hz, and in particular, has a sound absorption coefficient value of 0.96 at 4000 Hz. Due to the coating of the structure using polypyrrole as a conductive polymer, it has a higher thermal conductivity value (0.286 W m–1 K–1) than MF (0.033 W m–1 K–1). This structure also has high structural stability and elastic recovery performance, so it has the same mechanical performance, even after 500 repeated deformations.

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