There is a great interest in using micro and nano scale ingredients as fillers to create composites with enhanced physical properties. This thesis research explores the improvements these fillers offer with focus on combining both micro and nano ingredients to make multi-scale polymer composites. This investigation reveals the interplay of ingredient mixing, microstructural evolution, and processing conditions and characterizes the improvements of thermal and mechanical properties. This data is used to develop fundamental processing-structure-property relationships of these multi-scale composites across different concentrations of microscale and nanoscale ingredients and processing conditions in order to optimize their development.