Polyhydroxyalkanoates as Sustainable Agricultural Plastics: Processing Strategies, Performance, and Environmental Perspectives

ABSTRACT The widespread use of synthetic plastics in agriculture has significantly enhanced crop productivity and resource efficiency, but it has also generated severe and long‐lasting environmental challenges, including microplastic accumulation and soil degradation. Developing bio‐based and biodegradable alternatives that can perform effectively under agricultural conditions is therefore essential to advancing sustainable farming and environmental protection. This review critically examines polyhydroxyalkanoates (PHAs), a versatile family of biodegradable polyesters derived from natural sources, as promising substitutes for conventional agricultural plastics. Emphasis is placed on the relationships between polymer structure, processing behavior, and resulting mechanical and biodegradation properties that determine their suitability for key applications such as mulch films, seedling trays, and growth foams. Recent progress in blending strategies, additive incorporation and melt processing of PHAs, aimed at improving processability and mechanical performance, is discussed in detail. The review also identifies major challenges related to cost, scalability, and environmental performance under real‐field conditions, and highlights future research directions toward optimizing PHAs for circular and climate‐resilient agricultural systems.