As a traditional industry, the leather industry has witnessed rapid development in China since the 1980s. China has now become one of the world’s most important production centers for leather and leather products, with its export output accounting for more than 50% of the light industry at its peak. However, with the continuous improvement of people’s living standards and the acceleration of the modernization of national defense, the research and development of functional eco-leather has become a development trend of the leather industry. Modern life requires leather not only to be durable and wearable, but also eco-friendly and functional, such as hydrophobic and antifouling properties, yellowing resistance, antistatic performance, etc. Modern warfare demands that leather possess functions including flame retardancy, wear resistance, electromagnetic shielding, waterproof and moisture permeability, and intelligent sensing to meet the requirements of different combat environments, Bao Yan explained when talking about her professional field.

“Doing scientific research requires focusing on the key points. In fact, there are technological bottlenecks in the development of the leather industry.” Bao Yan, who has always been rigorous in her work, told us: “Leather chemicals are the ‘seasoning’ in leather processing. The use of chemicals determines the quality of leather. However, there are relatively few functional green leather chemicals available on the market, which can hardly meet the demand for the research and development of functional eco-leather. Therefore, in-depth research on function-oriented green leather chemicals and exploration of the underlying scientific issues are of great scientific value and practical significance for promoting the sustainable development of the leather industry.”

Targeting industrial pain points and advancing scientific research, facing the main battlefield of the national economy and taking the high-quality development of the leather industry as her mission, Bao Yan has long been engaged in the research of functional green leather chemicals in western China, and has made substantial scientific and technological achievements in three major areas: green leather tanning, dyeing and finishing technologies, functional leather coating materials, and intelligent wearable leather manufacturing.

First, in response to chromium pollution in the tanning industry and the lack of research and development of high-strength and tough leather chemicals, she innovatively proposed the preparation of polymer-based layered clay nanocomposites via in-situ intercalation polymerization and atom transfer radical polymerization. By controlling the molecular weight of polymers, the structure of layered clays and the types of reactive groups, interpenetrating network crosslinking is formed within leather fibers, thereby achieving chromium-free or low-chromium tanning and reinforcing and toughening leather fibers.

Second, taking advantage of the inherent characteristics and structural designability of hollow nanomaterials, she innovatively developed leather coating materials with diverse functional properties. For instance, she put forward a new strategy of “pore formation via morphology control”, overcoming the limitation of poor water vapor permeability of leather coatings, and elucidated the multi-path transport behavior of water vapor molecules in leather. Furthermore, she invented the key technology of stabilizing polyacrylate Pickering emulsions with hollow nanomaterials, breaking through the technical bottleneck that water resistance and moisture permeability of leather coatings are difficult to achieve simultaneously.

Third, the development of intelligent wearable electronic devices based on natural leather is the key to promoting the high-end and intelligent development of leather. She established the key technology integrating conductive network construction and tanning, revealed the response mechanism of heterogeneous conductive networks under cross-scale deformation of multi-level collagen fibers, and developed intelligent sensing leather materials capable of monitoring human motion.

“Breakthroughs in scientific and technological achievements are based on the unique multi-level structure and performance characteristics of leather, following the design concept of constructing green chemicals for leather through the co-regulation of polymer molecular design and inorganic nanomaterials,” Bao Yan said of her achievements. “The research outcomes have not only enhanced the added value of traditional leather and its products as well as the core competitiveness of the leather chemical industry, broken the monopoly of foreign products in the market, but also met people’s demand for the functionality and quality of high-end leather and its products, driving the transformation, upgrading, quality improvement and efficiency enhancement of the leather industry.”