Thermoplastic starch with deep eutectic solvents and montmorillonite as a base for composite materials

Thermoplastic starch (TPS) materials were prepared from potato starch, deep eutectic solvents (DES) as plasticizers [choline chloride (ChCI) with urea (U) or imidazole (IM) at molar ratio 1:2 and 3:7, respectively] and urea intercalated montmorillonite (UM). Extrusion and thermocompression were used as processing methods. It was found that UM resulted in decreasing melt viscosities of TPS composite materials at processing temperature range (120-140 degrees C), especially pronounced when ChCl/IM was applied. XRD revealed differences between values door parameter for UM and TPS/DES-UM materials, as well as amorphization of the starch-based films. Thermomechanical, mechanical properties and contact angle values were dependent on the type of applied plasticizer and UM content. Moreover, it was found that increasing clay content resulted in decrease of TPS/UM composites thermal conductivity.