ON THE MECHANICAL-PROPERTIES OF NATIVE STARCH GRANULES

As a fundamental prerequisite for starch based material development, we set up a method to determine mechanical properties of native starch granules. Instead of measuring tiny single granules, we developed an indirect procedure. It relies on a verified composite material theory and simple tensile tests with starch filled plastics. Resulting data for native potato starch granules: elastic modulus 2.7 GPa, tensile strength 60 MPa, indentation hardness 113 N/mm2. These data are similar to those of rigid thermoplastics.