Synthesis, Structural Characterization, and Thermal Properties of the Poly(methylmethacrylate)/δ-FeOOH Hybrid Material: an Experimental and Theoretical Study

Theδ-FeOOH/PMMA nanocomposites with 0.5 and 2.5 wt.% ofδ-FeOOH were prepared by grafting 3-(trimethoxysilyl)propyl methacrylate on the surface of the iron oxyhydroxide particles. The FTIR spectra of theδ-FeOOH/PMMA nanocomposites showed that the silane monomers were covalently attached to theδ-FeOOH particles. Because of the strong interaction between the PMMA andδ-FeOOH nanoparticles, the thermal stability of theδ-FeOOH/PMMA nanocomposites was improved compared to the pure PMMA. The SEM analysis conferred the size agglomerate of particles regarding the morphology of samples. The theoretical study enabled a better understanding of the interaction of the polymer with the iron oxyhydroxide. The DFT-based calculations reinforce the radical trapping mechanism of stabilization of nanocomposites; that is, Fe3+species might be able to accept electrons coming from the organic phase that decomposes via radical unzipping. The radical scavenge effect delays the weight loss of polymer.