Thermoplastic starch (TPS)/polycaprolactone (PCL) blends were obtained by melt mixing. First, the best formulation of thermoplastic starch (starch, plasticizer and additives) was studied. The obtained films were characterized by means of differential scanning calorimetry, DSC (melting temperature and crystallinity degree); thermogravimetric analysis, TGA (real composition of the blend and thermal stability); tensile tests (mechanical properties); infrared spectroscopy, FTIR (interactions between components); scanning electron microscopy, SEM (morphology); and water absorption tests. The effect of PCL/TPS ratio on the previously mentioned characteristics and properties were studied. In addition, the effect of using PCL modified with maleic anhydride as compatibilizer was also analyzed. An optimal compatibilizer content was found improving the mechanical properties and slowing down the degradation rate in soil of the blends. On the other hand, a slight increase in the water absorption of the blends was found in comparison with the noncompatibilized ones.

In this article, biodegradable polymer/clay nanocomposites were prepared. The matrices used were based on blends of Polycaprolactone (PCL) and Anhydride‐Functional Polycaprolactone (PCL‐gMA) with Thermoplastic Starch (TPS). Nanocomposites films based on PCL/TPS and PCL/PCL‐g‐MA/TPS blends reinforced with 1 and 3 wt % of natural montmorillonite and two organo‐modified ones were prepared by melt intercalation followed by compression molding. The study was designed focusing on packaging applications. Grafting maleic anhydride onto PCL was efficient to improve PCL/TPS compatibility but did not modify matrix/nanoclay interaction. Matrix compatibilization and nanoclays increased the Younǵs modulus and slightly decreased the maximum stress of the TPS/PCL matrix. Nanoclay functionalization improved nanoclay dispersion in the blends but it was not reflected in mechanical properties improvements. The water adsorption of the compatibilized matrix was reduced after clay incorporation. A slight decrease in the biodegradation rate was observed with the addition of nanoclay. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44163.