Mechanical enhancement of amine‐functionalized TiO₂ reinforced polyimine composites

Abstract

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 (amTiO2MS) 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 amTiO2MS and TiO2MS in the polyimine matrices. The investigation of mechanical properties of the amTiO2MS enhanced polyimine composites and control samples indicated that incorporation of amTiO2MS and TiO2MS exhibited different characteristic distribution, which strongly affected the performance of the composites. The optimal filling concentration of amTiO2MS was found to be 3%, with which the microspheres were uniformly distributed in the polyimine matrix. The self‐healing behavior of the polyimine‐amTiO2‐X was also studied. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46446.

Double‐Layer Nacre‐Inspired Polyimide‐Mica Nanocomposite Films with Excellent Mechanical Stability for LEO Environmental Conditions

“…In addition, the strength and modulus of the single-layer PI-Mica film are superior to those of other PI-based composite films (Figure 2e and Table S1, Supporting Information). [15,28,[31][32][33][34][35][36][37][38][39][40][41] The improvement in the mechanical properties of the final singlelayer PI-Mica film is mainly attributed to its ordered and uniform layered microstructure. [42,43] However, we found that after tensile failure in single-layer PI-Mica films, many of the mica nanosheets were pulled out from the PI matrix at the fracture location, forming prominent trapezoidal structures and irregular deflections (Figure S4b-f, Supporting Information).…”

Thermolatent Heterogeneous Epoxy–Acid Formulation for the Manufacture of Preimpregnated Sheets and Composites with Vitrimer Properties

“…The vitrimer concept was first demonstrated on epoxy networks. Notwithstanding the existence of alternative chemistry, − the epoxy route remains the straightforward option for transfer of the vitrimer concept in structural composite applications. Proof that epoxy vitrimers are a suitable matrix for FRP composites has been given several times: ,− Chabert et al produced vitrimer matrices with exchangeable ester links and a T α value > 100 °C .…”