Effect of Plasticizers on Properties, Retrogradation, and Processing of Extrusion‐Obtained Thermoplastic Starch: A Review

Abstract Thermoplastic starch (TPS) offers an alternative to petrochemical‐based plastics because as well as being a final product in itself, TPS can be used as a precursor for the production of new materials. In addition to high temperature and shear, the presence of plasticizers is essential in the TPS production process, to break the strong inter‐ and intra‐molecular interactions of the starch chains. The properties of these plasticizers—their functional groups, molecular weight, thermal stability, and compatibility with the polymer, among others—play an important role in the production of TPS. This work therefore brings together research evaluating starch–plasticizer molecular interactions and their effect on the structure, polymer properties, retrogradation, and processing of TPS obtained by extrusion; in addition, it collects and analyzes information on the process conditions used in the extrusion of different starches in the presence of different plasticizers. The objective of this review is to provide a clear description of the importance of the effect of plasticizers on the properties of TPS obtained by extrusion, indicating the potential of some plasticizers to broaden the field of application of TPS.