Study of the properties of Thermoplastic Starch films using Glycerol or Sorbitol as plasticizers

Abstract

In this work, thermoplastic starch (TPS) films were obtained using the casting technique. Two types of natural plasticizers were used, glycerol and sorbitol, and the behavior of both materials was compared by determining the characteristic properties. The crystallinity of the films was determined by the X-ray diffraction (XRD) technique, while the barrier properties were evaluated through vapor permeation (WVP) measurement. In addition, the thermal stability of the samples was analyzed by means of thermogravimetric tests and uniaxial tensile tests were used to evaluate their mechanical properties.

The results revealed that the incorporation of sorbitol in starch films leads to higher thermal stability of the material, as well as an increase in the degree of crystallinity compared to the use of glycerol as a plasticizer. Additionally, a decrease in water vapor permeation was observed, without significantly affecting the mechanical properties of the material.