The PP/TPS (70/30) blends with and without compatibilizer agent were manufactured in the twin-screw extruder (Haake Rheomex, model PTW16/25) with screw diameter of 16 mm, L/D ratio of 25 and 120 rpm. The extrusion was conducted using a temperature profile from 160 to 180 °C (Fig. 1, part II). Table 2 shows the composition of each blend developed. The compatibilizer agents were used at constant amount of 3% w/w in all cases throughout the study. This amount was chosen according to Liu, Wang, & Sun (2003), who studied the critical interfacial concentration of a type of compatibilizer on starch blends with a polyolefin.