Effect of the Chemical Modification of Diatomite/Isotactic Polypropylene Composite on the Rheological, Morphological and Mechanical Properties

The present study deals with the effect of the Diatomite (D) microcomposite with and without chemical modification in a polypropylene (iPP) blend. The objective is to achieve a material with a better performance at a lower cost and more accessible and more suitable processing. The chemical surface modification of Diatomite (MD) was achieved using a crosslinking system based on a mixture of sulfur, accelerator, and peroxide. The iPP/Diatomite composite was prepared by batch melt mixing in a Brabender Plasti-Corde under intense shearing at high temperatures and varying the Diatomite content from 0 to 15 wt%. The rheological behavior was examined by monitoring the Brabender Plasti-Corde torque/time rheographs. Different techniques were used to characterize the sample: Fourier transform infrared spectroscopy (FTIR), WAXS, SEM, and DSC. In addition, tensile strength tests and impact strength mechanical tests were conducted to study the performance. It was found that chemical modification strongly affected rheological behavior and generated a new rheological characteristic compared to the composites without modification. This has induced a new structure form that has improved mechanical properties. Moreover, the chemical modification used and due to its simplicity, can be successfully used on an industrial scale with the appropriate process.