Printable Liquid Metal Particles‐Silicone Composite Conductive Ink With Extended Pot Life for Stretchable Electronics

Abstract

Liquid metal particles‐silicone composite ink has garnered significant attention in the field of stretchable electronics due to its exceptional conductivity and deformability. However, traditional platinum‐catalyzed addition‐cure liquid silicone rubber‐based conductive ink suffers from an extremely short pot life at room temperature, which leads to premature crosslinking, nozzle jamming, and material waste during the printing process. To address this challenge, this study introduces a liquid multiple vinyl siloxane (PC‐611) as an inhibitor of the hydrosilylation reaction, which can form a reversible chelation with the platinum catalyst, successfully extending the room‐temperature pot life to over 10 days while enabling rapid curing at 100°C when above 2 wt.% PC‐611 content. Furthermore, the composite ink exhibits excellent shear‐thinning rheological properties even after being stored for ten days, making it highly compatible with direct ink writing (DIW). The printed flexible circuits demonstrate robust electromechanical stability and show a resistance change ratio of less than 0.4 under 30% strain. The composite ink formulation proposed herein effectively resolves the ink storage and process stability challenge during the manufacturing process of stretchable circuits, and offers a reliable solution for the large‐scale fabrication of silicone‐based stretchable electronic devices.