Effects of silane coupling agent and maleic anhydride grafted polypropylene on the morphology and viscoelastic properties of polypropylene-mica composites

In this study, morphology, and dynamic and mechanical properties of polypropylene-mica (PP-Mica) composites were investigated. To enhance the adhesion between PP and mica, maleic anhydride-grafted PP (MAPP) and treated mica with silane coupling agent were used. MAPP (as a compatibilizer) and silane coupling agent (as a filler surface modifier) caused an interfacial bonding in the mica filled polypropylene composites. The effect of mica content, MAPP, and treated mica with silane coupling agent on the morphological properties were investigated by Scanning Electron Microscopy (SEM). The results showed that with increasing MAPP or silane coupling agent, dispersion of filler and adhesion between PP and filler were improved. Mechanical data showed that with increasing MAPP and mica treated with silane coupling agent, tensile modulus and flextural strength of composites were enhanced. Dynamic rheological behavior of composites was also investigated within the domain of linear viscoelasticity. The rheological observations indicated that the complex viscosity, storage and loss moduli increased, and tan 5 decreased with increasing mica content.