Mechanical and Electrical Robust Self-Healable and Recyclable Silicone Elastomer via Combed Siloxane Precursor

Abstract

Silicone elastomers are valued for their mechanical and insulating qualities but traditionally cannot self-heal, limiting their long-term utility. This research presents a dynamic silicone network created using combed silicone precursors, effectively reducing synthesis costs and enhancing self-healing capabilities. The network incorporates dynamic cross-linking via aminopropyl groups that react with isocyanate and bulky secondary amines, giving materials that achieve over 80% healing efficiency for mechanical properties and can repair electrical breakdown holes. The material also shows excellent recyclability, retaining more than 80% of its mechanical properties and over 90% of its DC breakdown strength. Higher crosslink density improves mechanical strength and insulation but reduces healing and recycling efficiency. Conversely, increasing the content of dynamic bonds improves healability and reprocessability, although at some cost to mechanical strength. This innovative approach provides a cost-effective, highly functional solution for advanced electrical insulation needs.