MECHANICAL-PROPERTIES OF STARCH-FILLED POLYMER COMPOUNDS

In continuation of the investigations described in [10] important mechanical properties of native potato, maize and wheat starch granules have been determined. With these results and under precondition of a sufficient interfacial quality the resulting mechanical properties of the composites reinforced with starch granules could become predicted theoretically. These theoretically calculated mechanical parameters have been verified by tensile tests of the different composite materials. For evaluation of the interfacial quality a model for failure of unidirectional reinforced materials has been used, applied to the investigated particle reinforced composites and discussed in detail on the background of a few choosen, biodegradable composites. The results of the investigations certified that the mechanical properties of the matrix materials could become partly improved by their reinforcement with starch granules. Al the same time the final costs of the composite materials could be reduced in consequence of the low costs of nativ starch of about 1 DM/kg and the degradation behaviour could also have been accelerated by an increasing amount of starch. The maximum amount of starch has been limited to 40wt-%. Up to this filling ratio the examined materials allowed processing almost without complications.