Enhanced thermal stability and mechanical properties of polypropylene matrices reinforced with SiO₂ nanoparticles

Abstract The current study focuses on incorporating SiO 2 nano-fillers into a polypropylene matrix to enhance and regulate the coefficient of thermal expansion (CTE) while simultaneously improving physical, mechanical, and thermal properties. This approach involves adding small quantities of SiO 2 filler to occupy vacant spaces between polymer chains, reducing the CTE of the polymer without affecting its structure. Silicon dioxide nanoparticles (SiO2-NPs) were added to a polypropylene (PP) matrix at various concentrations (1%wt, 2%wt, 3%wt, 4%wt, 5%wt, 6%wt). The prepared samples underwent characterization through techniques including x-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), and differential scanning calorimetry (DSC), along with analysis of the coefficient of thermal expansion, Young’s modulus, and tensile strength. Observations revealed that the inclusion of small quantities of filler significantly enhances the mechanical and thermal properties of PP, particularly at 3%wt of SiO 2 , which exhibited the lowest CTE value. This methodology can be regarded as an effective approach for controlling the CTE value of polymers, potentially opening avenues for various industrial applications of these materials.