Effect of ionic liquid 1-buyl-3-methylimidazolium halide on the structure and tensile property of PBS/corn starch blends.

As a promising biodegradable resin, poly (butylene succinate) (PBS) is often blended with starch to reduce the cost. In this paper, 1-buyl-3-methylimidazolium halide pre-plasticized corn starch (CS) was blended with PBS to prepare PBS/corn starch blend material modified by ionic liquid (PBS/CS-IL). Ionic liquid (IL) acted as plasticizer and compatibilizer, and the effects of 1-butyl-3-methylimidazolium halide with different halogen anion on PBS/Starch blends were explored. The effects of IL on the structure and tensile property of PBS/Starch blends were evaluated by FTIR, SEM, DSC, TGA and XRD, respectively. Test results showed that the addition of IL significantly reduced the crystallinity of PBS/Starch blends, and the size of starch particles in the PBS matrix was also effectively reduced. IL also acted as a compatibilizer of starch and PBS, and induced the morphology of the blends to change from "sea-island" structure to homogeneous phase. The results of the tensile test showed that compared with the PBS/Starch blend without IL, the elongation at break of PBS/CS-IL increased from 22% to 93%. This study provided a simple and feasible method for the preparation of low-cost PBS bio-composite materials, and provided theoretical support for future industrial production.

The effects of different inorganic salts on the structure and properties of ionic liquid plasticized starch/poly(butylene succinate) blends.

1-Butyl-3-methylimidazole chloride ([BMIM]Cl) plasticized starch/poly(butylene succinate) (PBS) blends containing inorganic salts with different cations were prepared by a Haake mixer. The compatibility, thermal behaviors including crystallinity, crystallization temperature and melting temperature, thermal stability, and mechanical properties of these blends were systematically investigated by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The results showed that the inorganic salts could interact strongly with [BMIM]Cl plasticized starch/PBS blends to improve their mechanical properties, while the thermal stability of the [BMIM]Cl plasticized starch/PBS blends was simultaneously reduced. The SEM results suggested that the compatibility of [BMIM]Cl plasticized starch and PBS was significantly improved with increasing inorganic salt content. Furthermore, by incorporating inorganic salts, the melting enthalpy (ΔH m), crystallinity (X c), and cold crystallization temperature (T cc) of the blends were decreased.