Conclusions
In this paper cornstarch plasticized with glycerol (TPS) was incorporated in a polypropylene matrix.
TPS addition increased the density of the blends. According to test void content, car-boxylic acids or PPgMA insertion had the same behavior. Blendswithout compatibilizer agent had a poor interfacial adhesion, thusresulting in reduced mechanical properties. Blends made with C14,C16 and C18 carboxylic acids of myristic, palmitic and stearicacid proved to be equivalent or better compatibilizers when com-pared to maleic anhydride polypropylene and no compatibilizer.The adhesion between both polymers phases was improved andthe tensile strength, elongation and impact strength increased bythe addition of carboxylic acids. Among blends, PP/TPS/C14 blendpresented the highest impact energy, showing a slightly betterperformance. Results from DSC, SEM, impact and tensile strengthanalyses suggest the improved compatibility was attributed to achemical reaction between hydroxyl groups in starch and carboxyl groups in acids and the interaction between long hydrocarbonchain in acid and PP. Further works will be carried out to confirmthe increased biodegradability of these blends.