Preparation of epoxy resin composite based on thermochromic microcapsules and application in temperature monitoring for power equipment

Abstract Abnormal temperature rise in power equipment is a primary cause of insulation aging and grid failures. Conventional temperature monitoring technologies face challenges such as poor environmental adaptability and high costs. This study presents a novel thermochromic microcapsule-composite insulation material. Reversible color-changing microcapsules, prepared by encapsulating thermochromic substances in melamine-formaldehyde resin shells, are integrated into an epoxy matrix to form a functional coating. Experimental results show uniform particle size distribution, dense shell structure, and excellent thermal stability of the microcapsules. The thermal-sensing composite exhibits high temperature response sensitivity with distinct chromatic contrast. Electrical tests confirm that the microcapsule-doped coating maintains stable dielectric properties under power frequency conditions. This material integrates temperature visualization and insulation functions, offering a cost-efficient solution for localized overheating monitoring in power equipment.