Processing and characterization of thermoplastic starch/polycaprolactone/compatibilizer ternary blends for packaging applications

Abstract

Thermoplastic starch (TPS)/polycaprolactone(PCL) blends were obtained by melt mixing. First, thebest formulation of thermoplastic starch (starch, plasticizerand additives) was studied. The obtained filmswere characterized by means of differential scanningcalorimetry, DSC (melting temperature and crystallinitydegree); thermogravimetric analysis, TGA (real compositionof the blend and thermal stability); tensile tests(mechanical properties); infrared spectroscopy, FTIR(interactions between components); scanning electronmicroscopy, SEM (morphology); and water absorptiontests. The effect of PCL/TPS ratio on the previouslymentioned characteristics and properties were studied.In addition, the effect of using PCL modified withmaleic anhydride as compatibilizer was also analyzed.An optimal compatibilizer content was found improvingthe mechanical properties and slowing down thedegradation rate in soil of the blends. On the otherhand, a slight increase in the water absorption of theblends was found in comparison with the noncompatibilizedones.