Halogen-free polymer composites: advancing sustainable and high-performance flexible electronics

Flexible electronics, including wearable devices, foldable displays, sensors, and energy storage solutions are revolutionizing modern technology. These applications demand materials that are not only high-performing but also environmentally sustainable. Traditional flame-retardant polymer composites often rely on halogenated flame retardants, which pose significant environmental and health risks due to their toxic and non-biodegradable nature. In contrast, halogen-free polymer composites emerge as a sustainable alternative, offering both safety and superior performance. This review investigates the latest advancements in halogen-free polymer composites, emphasizing their environmental benefits and advanced performance characteristics such as enhanced flexibility, robustness, electrical conductivity, and thermal stability. Recent innovations include the integration of nanomaterials, which significantly improved the electrical and thermal properties of these composites, and the adoption of advanced fabrication techniques such as 3D printing, which enhanced scalability and design flexibility. Additionally, the review highlights the role of sustainable materials and bio-based polymers in the development of these composites, contributing to a reduced environmental footprint. Despite these advancements, significant gaps have been remained, particularly concerning the long-term stability and large-scale manufacturing processes of these composites. Addressing these challenges is crucial for the widespread adoption of halogen-free polymer composites in flexible electronics. This review aims to provide a comprehensive overview of the current challenges and recent innovations, ultimately paving the way for future research and development in this promising field. By identifying and exploring these gaps, the review seeks to facilitate the advancement of safer, more sustainable materials for next-generation flexible electronic devices.