Effect of Plasticizer and Compatibilizer on Properties of Polybutylene Adipate-Co-Terephthalate (PBAT) with Acetylated Starch

Immiscible and incompatibility between the hydrophilic fiber phase and hydrophobic matrix phase results in a poor stress transfer between the two phases and deterioration in mechanical, physical, and barrier properties. Thus, this study aims to enhance the compatibility between hydrophobic polybutylene adipate-co-terephthalate (PBAT) and hydrophilic nature corn starch (CS) by substituting native corn starch with acetylated corn starch (ACS). The acetylation treatment was used to improve the hydrophobicity of corn starch. The native corn starch was used as a reference to study the effect of acetylation. Challenges in incorporating fillers into hydrophobic PBAT were overcome by adding plasticizer; sorbitol (S) and compatibilizers; maleic anhydride (MAH) and dicumyl peroxide (DCP). The composite films were characterized by fourier transform infrared (FTIR), tensile properties, differential scanning calorimetry (DSC), water contact angle (WCA) measurement, and thermogravimetric analysis (TGA). The morphology of the composites was examined by scanning electron microscopy (SEM). The tensile properties of PBAT/ACS were improved by adding compatibilizers. Meanwhile, adding plasticizer improved the tensile properties of PBAT/CS. PBAT/ACS/MAH composite possessed a tensile strength of 15.47 MPa, modulus of 95.30 MPa, and strain at break of 170.81%, while PBAT/CS/30S composite possessed tensile strength of 8.59 MPa, modulus of 104.60 MPa and strain at break of 1037.91% which have potential use in packaging applications.