Poly(butylene succinate) (PBS) and polylactide (PLA) were blended in a co-rotating twin-screw extruder with various contents of PBS from 0 to 100 wt%. The effect of PBS content on the thermal and mechanical properties of PBS/PLA blends was investigated by using DSC, softening point measurements, a Charpy impact test and tensile testing. The Fourier transform infrared spectra showed that the polymers are immiscible, but the addition of PBS could modify the PLA structure in PBS/PLA blends by changing the content of amorphous and crystalline phases. In addition, the cold crystallization temperature of PLA in blends decreases in comparison with pure PLA, which shows that PBS could have a plasticizing effect on PLA. This is confirmed by the results of DSC analysis. The mechanical properties of the blends depend on the percentage of PBS addition. Typically, the mechanical properties of PBS/PLA blends are intermediate between the properties of the polyesters from which they are obtained. However, in some cases unexpected changes in mechanical properties of the blends were observed. For example, the elongation at break for a PBS/PLA blend containing 10 wt% PLA is higher than for pure PBS.

The paper presents the results of research on the influence of used plasticizing system on the structural and thermal properties of thermoplastic starch (TPS). The thermoplastic starch granulate was obtained by extrusion of native starch in the presence of a plasticizing system using a twin-screw extruder. Glycerol and urea were used as plasticizers in various proportions. In order to evaluate the effectiveness of the starch plasticization process, changes in its chemical structure were analyzed by infrared spectroscopy (FTIR), gel permeation chromatography (GPC) and X-ray diffraction (XRD). TPS thermal stability was determined by thermogravimetric analysis (TGA). An improvement in the efficiency of the plasticization process has been found for a urea-containing plasticizing system compared to the composition of starch plasticized only with glycerol. In addition, the XRD analysis confirms the beneficial effect of urea on the inhibition of starch retrogradation process.

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The paper presents study of the plant oils effect on the properties of starch/polyester blends. In the first stage of the study thermoplastic starch (TPS) with different amount of oils were prepared. I the second stage TPS materials were blended by extrusion process with commercially available biodegradable polyesters-poly(butylene succinate). Кеуwordsthermoplastic starch, poly(butylene succinate), blends, biodegradable films.