POLYHYDROXYBUTYRATE GRANULES MODIFICATION BY INDIRECT ATMOSPHERIC AIR PLASMA: APPLICATION IN BIPHASIC SYSTEM

Biopolymers, such as Polyhydroxybutyrate (PHB), present sustainable alternatives to conventional petroleum-based plastics, contributing to the development of environmentally friendly materials. However, their intrinsic properties often require enhancement for broader applications. Plasma technology emerges as a promising and versatile tool to modify the physicochemical characteristics of biopolymers. In this study, the effects of indirect air plasma treatment on PHB were evaluated. PHB granules dispersed in water were treated using a plasma pen for either 40 minutes (PHB-T40) or 60 minutes (PHB-T60). X-ray diffraction (XRD) analysis revealed that plasma treatment increased PHB crystallinity, with crystallinity values rising from 40.13% in untreated samples (PHB-NT) to 41.10% and 42.13% for PHB-T40 and PHB-T60, respectively. Chain reorientation was evidenced, along with changes in lattice parameters: an increase of 1.75% in 'a', 1.54% in 'b', and a decrease of 3.28% in 'c'. Scanning Electron Microscopy (SEM) showed reduced agglomerate size, while XRD indicated increases in crystallite size by 18.73% (PHB-T40) and 13.71% (PHB-T60). Thermal analyses further corroborated these findings.