Preparação e propriedades de compósitos de poli (3-hidroxibutirato) e argila: efeito da modificação e teor de carga.

Abstract

The influence of addition, purification and organophilization of a nanoparticulate mineral filler (bentonite clay) on the mechanical, thermal and morphological properties of PHB (polyhydroxybutyrate)/bentonite with concentrations ranging from 1 to 3% w/w was investigated. Pristine, purificed (sonication) and organophilic (Cetremide) bentonite clays, were characterized by FTIR and XRD before being incorporated into the PHB. The compositions were characterized with X-ray diffraction (XRD), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), scanning electron microscopy (SEM) and mechanical properties. Results showed that the purification and organophilization clay were effective. The incorporation of the organoclay to PHB caused an increase in tensile and storage modulus, while tensile and impact strength decreased with clay addition. Mechanical properties were significantly affected by prolonged exposure to elevated temperatures. Results suggest that the incorporation of the organoclay to PHB accelerates the thermal degradation of the polymer.