2. Thermoplastic starch (TPS) Thermoplastic material is a polymer that can be softened or melted under the application of heat and pressure and becomes hard solid when being cooled. Most plastics used nowadays are thermoplastics; thus they can be fabricated into films, containers or other shaped articles. Naturally, starch is not thermoplastic. The molecules in starch granule possess high intermolecular association leading to strong crystalline structure. As a result, its melting temperature is higher than its decomposition temperature; and the degradation would take place before crystal melting. However, with the aid of an additive called plasticizer, the crystalline structure of the starch granules can be destroyed, and the starch granules can be melted at a much lower temperature. The resulting material is called thermoplastic starch or TPS. The TPS pellets (Figure 2) can be fabricated into any desirable shaped articles by the standard equipments and the processing techniques used for the conventional plastics such as extruder, injection mold and film blowing.