Preparaçâo e caracterização reológica e térmica de blendas poli(caprolactona)/poli(butileno adipato-co-tereftalato)

Abstract

The goal of the present work is to prepare PCL/PBAT blends with 10 to 90% of each component, and to analyze their rheological characteristics, thermal stability, crystallization and melting behavior. Pure PCL and PBAT polymers and PCL/PBAT blends were melt processed in an internal laboratory mixer and characterized by differential scanning calorimetry (DSC), themogravimetric analysis (TGA), and scanning electron microscopy (SEM). The results obtained are consistent with the formation of an immiscible blend. The rate of degradation during the end of processing was estimated and revealed that all samples are stable and degrade minimally. It has been observed that the viscosity temperature coefficient is independent of the composition, but the pseudoplasticity index depends significantly on it. The DSC tests reveal a strong interaction between the components of the blend. Through the kinetic modeling, it was seen that the Pseudo-Avrami model presents acceptable divergences from results derived from DSC, being considered adequate. The thermal stability is not altered with the formation of the blends. SEM images indicate moderate interfacial adhesion.