Dual Non‐Thermal Physical and Chemical Modification Methods of Starch: Unlocking New Potentials for High‐Performance Polymer Composites

ABSTRACT Dual physical–chemical modification techniques of starch in polymer composites have gained attention to address the challenges associated with native and singly modified starches, with two primary categories: homogeneous and heterogeneous dual modification. The former involves combinations of two physical, chemical, or enzymatic modifications, whereas the latter involves pairs of different modifications. Within heterogeneous modification, the dual physical/chemical modification methods of starch stand out because of their advantages, including versatility in modification, targeted functional properties, enhanced properties, application specificity, and process optimization. This review highlights the impact of non‐thermal physical techniques paired with chemical modifications on the structure and properties of starch, specifically their effects on amylose, amylopectin, and their interactions in both crystalline and amorphous regions, affecting crystal structure packing and resulting in diverse functional properties for extensive applications in the starch industry. Additionally, understanding the precise mechanisms behind these modification techniques remains inconclusive, given the various influencing factors, such as processing parameters, starch origin, and environmental conditions. Addressing these factors through improved research methods or modified equipment can offer valuable insights into physical starch modification. Finally, the advantages and shortcomings of these techniques in starch processing are compared, and the knowledge gaps in this area are reviewed.