Polypropylene-modified kaolinite composites: Effect of chemical modification on mechanical, thermal and morphological properties

Abstract

The intercalation of kaolinite with an ammonium salt was performed. Untreated and treated kaolinite samples were examined by X-ray diffraction (XRD). PP/kaolinite compounds were prepared by the melt intercalation method. The effects of modified clay on properties of the prepared composites were studied. The XRD results showed that the treatment with the ammonium salt caused the return to the initial state of the clay. The thermogravimetric analysis thermograms (TGA) marked an increase in thermal degradation of the composites, while the differential scanning calorimetric (DSC) results showed the decrease of the crystallization temperature and the melting point in presence of clay in the matrix owing to the fact that the filler acts as reinforcing effect. The mechanical properties of the composites exhibited important variations, the morphology of the composites was further studied using scanning electron microscopy (SEM) and showed poor dispersion of used nanoclay in PP matrix.

Keywords: polypropylene; composites; kaolinite; surface treatment; melt intercalation