Covalent Incorporation of SiO₂ Nanoparticles in CO₂-Based Copolymers: Synthesis, Characterization, Morphology and Property Studies

A new strategy has been developed for covalent incorporation of SiO₂ nanoparticles (NPs) in the CO₂-based copolymer, poly(propylene carbonate-co-propylene oxide) (poly(PC-co-PO)). The poly(PC-co-PO)-g-SiO₂ nanocomposites was prepared by the combination of epoxy-CO₂ ringopening polymerization and the condensation reaction of chloride and hydroxyl groups of the polymer and the SiO₂ surface. FT-IR and NMR were employed for the characterization of the copolymers as well as nanocomposites. A uniform and spherical core–shell structure of poly(PC-co-PO)-g-SiO₂ nanocomposites was demonstrated from TEM and SEM images. An improved thermal property of the polymer matrix with incorporating SiO₂ nanoparticles was revealed by TGA study. The grafting of poly(PC-co-PO) considerably prevented the aggregation and improved the dispersibility of SiO₂ nanoparticles in toluene.