Single and Hybrid Mineral Fillers (Talc/Silica and Talc/Calcium Carbonate)-Filled Polypropylene Composites: Effects of Filler Loading and Ratios

Properties of single and hybrid fillers with polypropylene (PP) composites were studied in this research work. The effect of filler loadings of three types of mineral fillers, namely talc, silica, and CaCO3, was investigated. In hybrid composites systems, the effect of silica/talc (SI/T) and CaCO3/talc (CC/T) filler ratios at 40 wt% was determined. Generally, the results demonstrated that SI/T has higher modulus than CC/T but both hybrids did not have a significant effect on PP strength. In thermal properties, both hybrids have a nucleating ability as they increase the crystallization temperature and onset of crystallization temperature of PP. Results of analysis by TGA revealed that SI/T increased thermal stability of PP composites more than CC/T. Better flammability of the SI/T system is exhibited by lower burning rates of SI/T than CC/T, which indicates better thermal stability of the hybrid system. (C) 2014 Society of Plastics Engineers