FULLY BIO-BASED AND BIODEGRADABLE POLYLACTIC ACID/ POLY(3-HYDROXYBUTIRATE) BLENDS: USE OF A COMMON PLASTICIZER AS PERFORMANCE IMPROVEMENT STRATEGY

DAVID A. DAMICO; MAGDALENA L. IGLESIAS MONTES; LILIANA B. MANFREDI; VIVIANA P. CYRAS

POLYMER TESTING

ELSEVIER SCI LTD

Lugar: Amsterdam; Año: 2016 vol. 49 p. 22 - 28

0142-9418

In this work, biodegradable polymeric blends based on Poly(3-hydroxybutyrate) (PHB) and Polylactic Acid (PLA) were prepared by melt mixing. Trybutyrin, a bio-based plasticizer, was added at a fixed proportion in all blends. Crystal structure, percentage of crystallinity, miscibility, mechanical properties and permeation of fully biodegradable PHB/PLA blends were investigated by Differential Scanning Calorimetry (DSC), Fourier Transformed Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), tensile test and water vapor permeation test in detail. From the thermal test, two glass transition temperatures were found in the whole range of compositions, which reveals the immiscibility between PHB and PLA. Moreover, the biphasic melt further confirms this fact. Tensile test showed an increase in the elongation at break with the PLA content. SEM images reveal a debonding between the interfacial surfaces, which justifies the increase in the elongation at break. Water vapor permeation values for blends were slightly higher than that of the plasticized pristine polymer. The plasticized polymer blends showed valuable properties to extend the applications of PHB and PLA.