Special issue: biomass polymers – a sustainable platform with new functional materials

In recent years, the urgent need to transition toward a sustainable and circular economy has spurred significant research into biomass-derived polymers.1-5 As the world faces increasing concerns regarding climate change, resource depletion and plastic pollution, the development of renewable, biodegradable and functional materials has emerged as a critical priority. In this context, biomass polymers originating from natural sources, such as cellulose, hemicellulose, lignin, starch, chitosan and various plant- or microbial-based biopolymers, present a promising alternative to fossil-based plastics.6-9 This collection, titled ‘Biomass polymers: a sustainable platform with new functional materials’, brings together cutting-edge research and reviews that highlight the diverse potential of biomass polymers not only as environmentally friendly materials, but also as platforms for advanced functional applications. These include, but are not limited to, smart packaging, biomedical devices, energy storage systems, water purification technologies and stimuli-responsive systems. The contributions in this issue highlight the increasingly interdisciplinary nature of biomass polymer research. Spanning fundamental studies on polymer chemistry and structure–property relationships to advances in processing techniques and innovative applications, the works presented here reflect the substantial progress being made in leveraging nature-derived materials to meet modern technological demands. The research on microbial polyhydroxyalkanoates (PHAs) has been reviewed. Tanadchangsaeng et al. summarized the background and recent progress of PHAs.10 With tunable mechanical properties and excellent biocompatibility, PHAs are promising materials for biomedical applications. This review highlights recent advances in PHA-based medical devices, including 3D printing and scaffold development for tissue regeneration. Tsuge et al. reported the fine control of the surface properties and biodegradability of PHAs by introducing poly(ethylene glycol) (PEG) side chains using thiol–ene click chemistry.11 The PEG-modified PHAs showed enhanced wettability and antifouling properties, with reduced biodegradation at higher PEG content. This approach offers a promising strategy for tuning PHA functionality for broader material applications. As shown in this example, the synthesis of functional polymers from biomass-derived components and their practical applications are of great importance in industry. Koyama et al. reported a novel polymethacrylate incorporating rigid 2-acetamide-2-deoxyisosorbide units derived from chitin to develop biobased high-performance polymers with transparency and high glass transition temperatures.12 The resulting polymer exhibited excellent transparency, a significantly high glass transition temperature and promising thermal stability, demonstrating its potential for practical applications. In addition, the effective utilization of waste biomass remains a critical challenge in this field. Behera et al. reported biomass composites made from vetiver root fibers and polymerized soy matrix to develop biodegradable thermoplastics.13 The composites were evaluated under various natural degradation conditions, including seawater, fungi and termite exposure. Changes in mechanical properties, moisture absorption and structural integrity were analyzed, providing valuable insights into the biodegradation mechanisms of cellulosic composites. We are confident that this collection will inspire further innovation in the field and serve as a valuable resource for researchers, engineers and industry practitioners working toward a sustainable materials future. We would like to express our sincere gratitude to all the authors who contributed their high-quality work to this issue, and to the reviewers whose critical insights helped ensure the rigor and impact of these publications. We also thank the editorial team for their support in bringing this issue to fruition.