Gray Relational Analysis between Size Distribution and Impact Strength of Polypropylene/Hollow Glass Bead Composites

Abstract

The impact strength of V-notched U-notched and non-notched specimens of hollow glass bead filled polypropylene composite (PP/HGB) were measured by using Charpy impact tester, and the directed gray relational grade (GRG) between the HGB size distribution and the impact strength of the composites was determined by means of gray relational analysis (GRA) in order to investigate the influence of the HGB size distribution on the impact strength of the composites. The results indicated that the particles with size range from 0.00 to 24.7 µm have a positive influence on the impact strength of the composites, and the particles with size ranging from 18.90 to 24.7 µm have a greater positive influence than that of the particles with size range from 0.00 to 18.9 µm. While the particles with size ranging from 24.72 to 256.0 µm have a negative influence, especially the particles with size in a range from 100.60 to 256.0 µm. That is, the impact strength of the composites could be enhanced by increasing the particle content in the tested fillers with size range from 0.00 to 27.72 µm especially the particles with size ranging from 18.90 to 24.7 µm, whereas decreasing the particles content with size range from 24.72 to 256.0 µm, especially the particles with size range from 100.60 to 256.0 µm.