Study of the Physical and Mechanical Properties of Thermoplastic Starch/Poly(Lactic Acid) Blends Modified with Acid Agents

In this work, we present a functionalization strategy of starch-poly(lactic acid) (PLA) blends with organic acids. Lactic and acetic acid were used as agents, oleic was also included in the previous acids, aim finding synergy that thermodynamically benefits products provides hydrophobicity. The ratio starch sorbitol 70:30, added agent replaced 6% plasticizer; meanwhile, thermoplastic (TPS)–PLA blend proportion 70:30 considering modified TPS. mixtures obtained torque rheometer at 50 rpm for 10 min 150 °C. acids facilitated interactions between TPS PLA. Although PLA are not miscible, uniformly dispersed into matrix. Furthermore, reduction surface polarity achieved, which enabled wettability to reach values close those neat (TPS–L-PLA increased by 55% compared TPS–PLA). rheological results showed modulus similar general, there transitions from elastic viscous, viscous phase predominated. first second-order thermal did show significant changes. structural affinity lactic biopolymers (TPS–L-PLA) allowed greater interaction corroborated mechanical properties, resulting resistance respect pure blended TPS–PLA (28.9%). These particularly relevant packaging industry.