Modification of polypropylene with nanosized α-Al2O3 powders prepared by the mechanochemical method
Abstract
Nanosized α-Al2O3 powders were prepared by the mechanochemical method, with AlCl3 ṡ6H2O and NH4HCO3 as raw materials, the environmentally friendly starch as an effective dispersant. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were employed to characterize the ammonium aluminum carbonate hydroxide (AACH) precursor and products. The results show that nanosized spherical α-Al2O3 powders without hard agglomeration and with particle size in the range of 20-40 nm can be obtained by this novel and green method. Then, polypropylene (PP)/nano α-Al2O3 nanocomposites were prepared by melt blending in a mixer apparatus. The crystallization behavior and mechanical properties of PP/α-Al2O3 nanocomposites were further investigated in this study. Wide-angle X-ray diffraction (WAXD) results show that a small amount of β-crystal of PP forms after adding α-Al2O3 nanoparticles. According to differential scanning calorimetric (DSC) measurement, the α-Al2O3 nanoparticles make crystallization temperature of PP enhanced by acting as effective nucleating agents. The tensile strength and impact strength were both improved significantly with the addition of α-Al2O3 nanoparticles through tensile and impact tests. Scanning electron microscopy (SEM) observation showed that the fracture surface became rougher and further confirmed the above result.
- Publication:
-
Modern Physics Letters B
- Pub Date:
- September 2018
- DOI:
- 10.1142/S0217984918502962
- Bibcode:
- 2018MPLB...3250296G
- Keywords:
-
- Nanosized α-Al<SUB>2</SUB>O<SUB>3</SUB> powders;
- mechanochemical method;
- PP/α-Al<SUB>2</SUB>O<SUB>3</SUB> nanocomposites;
- crystallization behavior;
- mechanical properties