THERMOPLASTIC STARCH MODIFIED WITH MONTMORILLONITE AND WASTE POLYURETHANE FOAM

The properties of thermoplastic starch (TPS) initially plasticized either with glycerol (G) or a mixture of formamide and urea (F+M), modified with sodium montmorillonite (MMT-Na) or the organophilized (Nano Bent ZS1 or ZS3) and their mixtures with or without waste polyurethane foam powder have been determined and presented (Tables 3 and 4). The obtained mixtures were investigated with X-Ray diffraction (Figs. 1-3, 5) and the mechanical properties (tensile and flexural strength) also evaluated (Tables 1, 2, 5 and 6). The studies confirmed that the application of the two-component polar plasticizer (F+M) leads to the mixtures with higher elasticity and elongation at break and also lower tensile and flexural strengths than those plasticized with glycerol. It was found that the addition of the layered aluminosilicate nanofillers also led to a mixed intercalated/exfoliated dispersion in the polysaccharide matrix. In the case of the application of a 25 parts per weight of the powdered polyurethane foam/100 parts per weight of starch ratio in the TPS(F+M)/MMT/PUR mixture, an increase of several times in the Young's modulus and a pronounced decrease in elongation at break for these materials is achieved as compared to those obtained for the TPS(F+M) system.