Interfacial adhesion and mechanical properties of PMMA-coated CaCO3 nanoparticle reinforced PVC composites

Polymethyl methacrylate (PMMA)-coated nano-CaCO3 particles were prepared by in-situ emulsion polymerization. The mechanical properties of nano-CaCO3 particles-reinforced PVC were investigated using an AG-2000A universal testing machine and an XJU-2.75 izod impact tester; interfacial adhesion between CaCO3 nanoparticles and PVC matrix by SEM, and structure of PMMA coated on the surface of CaCO3 by FTIR and 1H-NMR. The results indicate that the PMMA coated on the nano CaCO3 particles consists mainly of syndiotactic structure, and their three tacticity contents were rr 52.8%, mm 7.3% and mr 39.9%, respectively. The interfacial adhesion between CaCO3 nanoparticles and PVC matrix was significantly improved when the CaCO3 nanoparticles were coated with PMMA, which led to increased Young's moduli and tensile strengths of the PMMA-coated CaCO3/PVC composites. The izod impact strengths of the composites were strongly affected by the PMMA coating thickness and increased significantly with increasing the volume fraction of CaCO3 filler in the composites.