Synergistic Mechanism of Thermal and Mechanical Properties in Bionic Hierarchical Sea Urchin Design for Silicone Rubber Composites

Abstract

There are challenges in synergistically enhancing the thermal-mechanical properties of silicone rubber (SR) composites for high-voltage cable accessories. This paper proposes a biomimetic microinterface design strategy inspired by sea urchin structures. The approach involves the amino functionalization of ZnO surfaces using a KH550 silane coupling agent. Then, epoxy-terminated polydimethylsiloxane (PDMS) is grafted via an opening ring reaction to construct branched structures on the ZnO surface. Fourier transform infrared spectroscopy and scanning electron microscopy confirmed the successful synthesis of modified ZnO and its dispersion within the silicone rubber matrix. SR composites with varying amounts of the modified ZnO filler were prepared, and their thermal conductivity, mechanical properties, and insulation performance were evaluated. The results indicate that this interfacial regulation strategy effectively enhances the filler dispersion and strengthens the interactions between the fillers and the matrix. This strategy also achieves the synergistic optimization of the thermal conductivity and mechanical properties at lower filler loadings. These results provide novel insights into addressing long-term reliability issues in cable accessories.