Mechanical enhancement of amine-functionalized TiO2 reinforced polyimine composites

Polyimine vitrimers are known for their malleability, which endows these materials with properties such as self-healing, recycling, and reshaping. To enhance the mechanical properties of the polyimine vitrimers, composites were fabricated by incorporating amine-functionalized TiO2 microspheres (amTiO(2)MS) into polyimine matrix. The pure polyimine matrix and polyimine composites hybridized with TiO2 microspheres (TiO2MS) without surface modification were also obtained and examined as the controls in characterization. X-ray powder diffraction, scanning electron microscopy, and energy dispersive X-ray spectroscopy were employed to demonstrate the presence and distribution of amTiO(2)MS and TiO2MS in the polyimine matrices. The investigation of mechanical properties of the amTiO(2)MS enhanced polyimine composites and control samples indicated that incorporation of amTiO(2)MS and TiO2MS exhibited different characteristic distribution, which strongly affected the performance of the composites. The optimal filling concentration of amTiO(2)MS was found to be 3%, with which the microspheres were uniformly distributed in the polyimine matrix. The self-healing behavior of the polyimine-amTiO(2)-X was also studied. (c) 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46446.