Morphological Features of Poly (3-Hydroxybutyrate)/Low Density Polyethylene Blends

In an effort to investigate the morphology of biodegradable films, the combination of DSC, SEM and FTIR polarization spectroscopy methods are used. The methods enable us to examine the structural and morphological peculiarities of extruded blend compositions on the base of PELD and poly(3-hydroxybutyrate) (PHB) at concentration of the latter ranges from 0 to 32 wt%. The blend components are thermodynamically incompatible and form morphological elements with good visible interfaces between disperse phase (PHB) and continuous matrix (LDPE). For film extrusion, blend components affect each other that is seen as the crystallinity drop for both PHB and LDPE. The dichroism measurements show that the axes of LDPE and PHB molecules are presumably located at right angle, therewith, the biggest axes of the PHB crysrlallites are oriented along the extrusion direction. The matrices at all blend ratios, besides 32wt% composition, are reinforced by alternative band and cylinder-like fibriles of PHB. The architecture of such morphological elements is carefully studied by SEM method.