Estudo da estabilidade térmica em processamento de PHB aditivado.

Abstract

In this study the thermal stability in processing of the poly (3- hydroxybutyrate- co-3- hydroxyvalerate ) PHBV ( Biocycle 1000) in the presence of the thermal stabilizing for polyesters additive BRUGGOLEN ® H10 and the effect of a styrenic - acrylic multifunctional epoxy oligomer ( Joncryl - POLYAD PR 002) marketed as chain extender for condensation polymers, intended to compensate the reduction of these polymers molar mass during processing were evaluated. The additived PHB and without additive were processed in a Haake internal mixer with roller type rotors. The influence of the temperature of the process and amount of additive in the molar mass of PHB was determined based on the measurements of torque. Mixtures (PHB and additive) were also characterized by fluid index rate (MFR) and Differential Scanning Calorimetry (DSC). The thermal instability of the polymer (PHB) in processing temperatures was demonstrated. The BRUGGOLEN addition on PHB resulted in the decrease of its molar mass. On the other hand, the addition of Joncryl promoted a slight increase in the molar mass of the polymer during processing, with the highest values obtained when the same was processed at 160 °C.