Journal of Biotechnology & Biomaterials
Open Access

Abstract

Starch has been considered as one of the most promising bioplastics primarily because of its attractive combination of availability and price. Thermoplastic starch (TPS) can be obtained by destruction of starch granules in the presence of plasticizers under specific conditions. Polyols such as glycerol, glycol, sorbitol, and sugars are the most widely used plasticizers. The main disadvantages of TPS consist in pronounced hydrophilic nature, the fast degradation rate and, in some cases, unsatisfactory mechanical properties. In spite of some industrial applications of TPS exist, high volume production of TPS-based materials is rare at present and occurs only in exceptional cases for non-demanding products. In this lecture the principles for substantial improvement of ultimate propereties of TPS are discussed. A number of possible modifications have been investigated to affect the mechanical properties, water uptake, and the structure of the materials. The experiments were aimed to the optimization of the ratio of amylose and amylopectin, selection of appropriate plasticizers including their mixtures, modification of hydrophilicity by chemical modification of hydrophobic functional groups or via crosslinking of TPS, and mixing the TPS with hydrophobic biodegradable polymers added as the minor component. In most cases the optimization resulted in a substantial changes of properties of TPS-based materials. The possible routes are discussed resulting in modified starch- based materials being able to compete with standard plastics in more demanding applications.

Biography

Email: Ivan.Chodak@savba.sk