The effect of mineral surface nature on the mechanical properties of mineral-filled polypropylene composites

The adhesion between the polymer matrix and the inorganic filler particles are the goal of various and tremendous studies. This issue is still occupying a big part of the researchers thinking to find a proper solution, however, its difficulty returns to different factors playing roles in it. Among these factors are the filler surface, i.e., hydrophobicity and hydrophilicity, functional groups on the surface, as well as mineral filler particle size distribution, and particle shape. Therefore, in the current study, the difference in mechanical properties for two mineral fillers; namely, silica and talc, differs in their surface and rheology properties were investigated. Results showed that the difference in the mechanical properties of the same matrix when the inorganic filler is different either in type or loading. Talc showed the better results in terms of Young’s modulus and impact strength, where silica showed higher values in terms of yield stress. Moreover, both minerals addition resulted drop in all strain measures, yet silica showed relatively higher measures than talc, but the relative difference measures between the two minerals decrease with increasing their percentage of additions. In brief, the introduction of inorganic fillers to polypropylene (PP) increases toughness, stiffness and strength of the mineral-filled PP end-products.