Recent Advances in Biodegradable Polymers and Plastics: Materials, Processing Technologies, Applications, and Future Perspectives

The increasing accumulation of persistent plastic waste has intensified research into biodegradable polymers as potential alternatives to conventional petroleum based plastics. Recent advances in polymer chemistry, biotechnology, nanotechnology, and sustainable manufacturing have enabled the development of materials with improved mechanical strength, thermal stability, processability, and controlled degradation characteristics. This review examines the classification, synthesis, modification, applications, and environmental implications of biodegradable polymers, with particular emphasis on polylactic acid (PLA), polyhydroxyalkanoates (PHAs), polybutylene succinate (PBS), polybutylene adipate terephthalate (PBAT), and polycaprolactone (PCL). Advances in microbial fermentation, renewable feedstocks, polymer blending, nanocomposite development, and enzyme assisted degradation are discussed in relation to material performance and end of life management. Emerging applications include food packaging, agricultural mulch films, biomedical devices, tissue engineering, and disposable consumer products. The review also evaluates the influence of polymer structure, crystallinity, molecular weight, temperature, moisture, and microbial activity on biodegradation. Although biodegradable plastics offer promising opportunities to reduce dependence on fossil resources and manage selected waste streams, their environmental benefits depend on production methods, product design, collection systems, and suitable treatment infrastructure. Importantly, bio based origin does not necessarily indicate biodegradability, and biodegradability does not guarantee rapid decomposition in natural environments. Recent literature emphasizes the importance of standardized testing, life cycle assessment, and application specific waste management. Future progress will require cost effective manufacturing, improved material performance, reliable biodegradation verification, and integration with circular economy strategies. Biodegradable polymers should therefore be considered complementary components of sustainable plastics management rather than universal replacements for conventional polymers.