Preparation and characterization of acetylated maltodextrin and its blend with poly(butylene adipate-co-terephthalate)

Acetylated maltodextrins (AMDs) were synthesized. It was found that maltodextrin (MD) was easily acetylated to form AMDs with high degree of substitution (DS). The DS of the prepared AMDs was much higher than that of acetylated corn starches (ACSs) obtained under the same reaction conditions. The differential scanning calorimetry (DSC) measurements clearly highlighted that AMD underwent a glass transition at about 109 °C. Moreover, AMD possessed higher thermal stability than MD. The AMD with DS 2.13 (AMD2.13) was melt-blended with poly(butylene adipate-co-terephthalate) (PBAT) to fabricate novel PBAT/AMD polymer blends. Rheological measurements indicated that AMD2.13 had a plasticizing effect on PBAT. Moreover, scanning electron microscopy (SEM) measurements indicated good interfacial adhesion between PBAT and AMD2.13. The onset temperature of non-isothermal melt crystallization of PBAT increased from 81.95 to 92.19 °C due to the favorable heterogeneous nucleation effect. Mechanical tests showed that the yield strength of the PBAT/AMD blends was enhanced.