- Volume 13 Issue 2
We tried to blend PLLA and PDLA at overall compositions to form PLA stereocomplexes (SC). The presence of the SC crystalline phase in the PLLA matrix was verified by differential scanning calorimetry (DSC). As a result, a various PDLA composition of the PLA SC blends can influence PLA SC formation. And the largest amount of PLA SC crystallites was formed when PLLA/PDLA ratio is 50/50. In addition, we have tried to do PLA SC toughening with two impact modifiers in 92/8, 85/15 ratio of PLLA/PDLA to enhance the mechanical properties such as impact strength. Thermal and mechanical properties of PLA SC were investigated by DSC, HDT, Izod impact tester and UTM. PLA SC formation decreased when 10-20 wt% of Strong120 (impact modifier) was added. On the other hand, there is no effect on PLA SC formation when 10-20% of Elvaloy (impact modifier) was added. HDT values dramatically increased over
Biodegradable;Stereocomplex;HDT;Impact Strength;Flexural Modulus
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