Preparation and Performance Study of Polypropylene Composites Modified with Different Functionalized SEBS and Nano-CaCO₃

In this study, polypropylene (PP) composites were developed using hydrogenated styrene–butadiene–styrene (SEBS), its functionalized derivatives, and nanocalcium carbonate (nano-CaCO3) via melt blending. The aim was to enhance PP’s mechanical and thermal properties through strategic material modification. Incorporating 20 wt % SEBS significantly boosted PP’s impact strength from 5.4 to 19.0 kJ/m2 and elongation at break from 637.3 to 1200.6% while maintaining the tensile strength above 20.1 MPa. Functionalization of SEBS with glycidyl methacrylate (GMA) and styrene (St) further improved the interfacial adhesion within the PP matrix. This resulted in an impact strength of 30.1 kJ/m2, elongation at break of 1445.3%, and tensile strength of 22.5 MPa with 10 wt % functionalized SEBS. The introduction of 6 wt % nano-CaCO3 further optimized the composite’s performance, increasing its impact strength to 38.4 kJ/m2, elongation at break to 1668.7%, and tensile strength to 27.5 MPa, along with enhanced thermal stability. These modifications led to overall improvements in PP’s mechanical properties, including a 611% increase in impact strength, a 162% increase in elongation at break, and a 24% increase in tensile strength. This work demonstrates a significant advancement in enhancing PP composites, offering potential for broader industrial applications.