Optimization of Zeolite as Filler in Polypropylene Composite

This article reports on optimization of natural zeolite as filler in polypropylene composite. Effects of zeolite loading and surface treatment were performed in this work. Prior to mixing process, zeolite was ground by ring mill into a powder form. The composites were prepared using Thermo Haake Polydrive internal mixer and then compression molded according to standard test specimen. Tensile and impact tests were performed to characterize the mechanical properties of untreated and treated composites. The obtained experimental values of Young’s modulus were then related to the theoretical predictions using a Halpin—Tsai equation. The theoretical prediction resulted in greater values of tensile modulus compared to the experimental values. A morphological study was done on the tensile fractured surface using a scanning electron microscopy. A Fourier transform infrared spectra analysis was performed on the composites to study the interaction between the polypropylene and functional group of stearic acid and vinyl silane. It was found that the tensile strength, elongation at break, and impact strength decreased but the Young’s modulus increased with increasing zeolite content. The addition of coupling agents was proved to enhance the mechanical properties of zeolite/polypropylene composite. However, stearic acid has little effect in improving the composite mechanical properties in comparison with vinyl silane.