Starch Foams and Their Additives: A Brief Review

Abstract

AbstractShort‐life packaging has been contributing to the increased consumption of polymers. Expanded polystyrene (EPS) is a material that is widely used in disposable packaging, however, its residue occupies a large volume, is difficult to degrade, and its recycling is expensive. That's why the interest in looking for a material of natural and biodegradable origin that can be an alternative to petrochemical‐based polymers. One possibility would be starch, which is a natural and biodegradable polysaccharide and can be extracted from different sources. However, natural starch does not have good properties for commercial application, requiring chemical modifications and/or the incorporation of additives. This article carried out a compilation of current studies that work on the development of packaging, whether film or foams, based on plasticized starch (TPS), and analyzes the influence of the incorporation of additives or treatments carried out in the starch. The blowing agent decreases foam density, cell size, and increases cell density. Incorporation of glycerol in starch foams increases the gelatinization temperature, decreases viscosity and resistance to expansion. The surfactant decreases the density and moisture absorption of the foam, the nucleating agent acted by increasing the mechanical strength and density of the foam, and decreases the absorption of water.